JP2017141026A - Vehicle speed control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle speed control system for solving problems of existing systems.SOLUTION: A vehicle speed control system for a vehicle having a plurality of wheels comprises: means for applying torque to at least one of the plurality of wheels; means for detecting a slip event between one or more of the wheels and a road surface over which the vehicle is travelling when the vehicle is in motion and for providing a slip detection output signal in the slip event. The system further comprises: means for receiving user input of target speed at which the vehicle is intended to travel; and means for maintaining the vehicle at the target speed independently of the slip detection output signal by applying torque to the at least one of the plurality of wheels.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a system for controlling the speed of a vehicle. Specifically, the present invention relates to a system that controls, but is not limited to, a speed of a land vehicle to a speed that can be driven on various different rough roads and conditions.

  In existing vehicle speed control systems, typically referred to as cruise control systems, the vehicle speed once set by the user is maintained on the road without further user intervention, thus improving the user experience.

  The user selects the speed that the car should maintain, and the car is maintained at that speed unless the user steps on the brake or in some systems the clutch. The cruise control system obtains its speed signal from a drive shaft or wheel speed sensor. Depressing the brake or clutch disables the cruise control system and allows the user to change the vehicle speed without resisting the system. The vehicle speed increases when the user depresses the accelerator pedal, and the vehicle returns to the preset cruise speed when the user releases the accelerator pedal.

  A more advanced cruise control system may be integrated into the engine management system and include an adaptive function that takes into account the distance to the preceding vehicle in a radar-based system. For example, the vehicle may be provided with a forward monitoring radar detection system that detects the speed and distance of the preceding vehicle so that a safe tracking speed and distance are automatically maintained without requiring user input. When the radar detection system detects a deceleration or other target of the preceding vehicle, the system sends a signal to the engine or brake system to reduce the vehicle speed accordingly.

  These systems usually only operate at specific speeds, typically above about 15 mph (about 24.1 km / h), and this speed is the condition under which the car travels in steady traffic conditions, especially highways or motorways. Then it is ideal. However, the cruise control system is not useful under congested traffic conditions where the vehicle speed tends to change significantly, and in particular cannot operate due to the minimum speed conditions. The minimum speed condition may be imposed on the cruise control system, for example, to reduce the risk of low speed collisions when parking. Thus, these systems are not useful under certain operating conditions (eg, at low speeds) and are set to be automatically disabled in conditions that the user may not wish to operate.

  It is also known to provide a control system for a motor vehicle that controls one or more vehicle subsystems. US Pat. No. 7,349,976, which is hereby incorporated herein by reference, includes a vehicle control system including a plurality of subsystems including an engine management system, a transmission controller, a steering wheel controller, a brake controller, and a suspension controller. Is described. Each subsystem operates in multiple subsystem function modes. The subsystem controller is coupled to the vehicle mode controller, which controls the subsystem controller to exhibit a request function mode that provides multiple driving modes of the vehicle. Each operation mode corresponds to a specific operation condition or a set of operation conditions, and each subsystem is set to a function mode that is optimal for those conditions in each mode. These conditions link to terrain types known as “special program off (SPO)” modes, such as grass, gravel, snow, mud and dredging, rocky crawls, sand, and highways where the car will travel. Has been. A car mode controller may be referred to as a terrain response (TR) (RTM) system or controller.

US Pat. No. 7,349,776 GB1111288.5 specification GB1211910.3 Specification GB12024227.9 specification

  It is to provide a vehicle speed control system that solves the problems of existing systems.

According to aspects of the present invention, systems, vehicles, and methods are provided.
According to one aspect of the present invention, a vehicle speed control system for a vehicle having a plurality of wheels has a configuration for automatically controlling the vehicle to a target set vehicle speed, and applies torque to at least one of the plurality of wheels. Means for detecting a slip event between one or more of a plurality of wheels during operation of the vehicle and a road surface on which the vehicle travels, and providing a slip detection output signal upon detection of the slip event; There is provided a vehicle speed control system including means for receiving a target vehicle speed input for driving the vehicle. The system further includes means for maintaining the target vehicle speed independent of the slip detection output signal. It is understood that the target vehicle speed input by the user is a target set speed of the automatic speed control system.

  In accordance with another aspect of the present invention, a vehicle speed control system for a vehicle having a plurality of wheels and a powertrain that provides torque to the wheels, wherein one or more of the plurality of wheels during vehicle operation. And means for receiving an input signal indicating a slip event between the vehicle and the road surface on which the vehicle travels, means for receiving a target vehicle speed input by the user to drive the vehicle, and means for outputting a torque request signal for controlling the vehicle powertrain A vehicle speed control system is provided that is operable to maintain the vehicle at the target vehicle speed independent of the slip detection output signal.

A problem with vehicle speed control systems, such as existing vehicle cruise control systems, is that the system is canceled when the vehicle detects a slip event of one or more wheels. This system is also canceled during anti-lock braking system (ABS), traction control system, stability control system, or other operation. While the techniques used by existing cruise control systems may be quite appropriate when driving on highways, these “on-highway” type cruise control systems typically have much slower driving speeds and topographic characteristics. It is unreliable and totally unsuitable for use in most off-road driving where slips frequently cause slip.
In other words, the on-highway cruise control system is not useful when driving on off-road conditions where wheel slip is not uncommon, bad and slippery.

  One benefit of the present invention is that speed-based control is provided that allows the selection of a very low target speed for advancing the vehicle without requiring pedal input by the user when the vehicle is running, The control is not invalidated even when the vehicle slip control mechanism is operated. Specifically, this makes it possible to control the vehicle speed under driving conditions such as slippery or frozen terrain where the wheels can slip relatively frequently.

  Another advantage of the present invention is that it is easier for the user to focus on traffic aspects such as route planning and obstacle avoidance because the user does not have to concentrate on vehicle speed adjustment. This means that the driving terrain of the car requires more attention from the user, for example off-road terrain (sand, rocks, gravel, etc.), ice or snow, or driving through deep water in a car. This is especially beneficial when it is difficult.

According to still another aspect of the present invention, there is provided a vehicle speed control system for a vehicle having a plurality of wheels, the means for adding torque to at least one of the plurality of wheels, and a user input of a target vehicle speed at which the vehicle travels. There is provided a vehicle speed control system including means for receiving, means for determining a terrain characteristic that the vehicle travels, and means for determining whether the target vehicle speed is appropriate for the terrain characteristic that the vehicle travels. The vehicle speed control system further includes means for applying a torque to at least one of the plurality of wheels to maintain the vehicle at the target vehicle speed only when it is determined that the target vehicle speed is appropriate.
In accordance with yet another aspect of the present invention, a storage device is provided that includes a carrier medium carrying computer readable code for controlling a vehicle to perform the method described below.
Preferred and / or optional features in any of the aspects of the invention shall be incorporated in any of the other aspects of the invention either alone or in appropriate combination.

  A vehicle speed control system that solves the problems of existing systems is provided.

FIG. 1 is a plan view of a vehicle according to an embodiment of the present invention. FIG. 2 is a side view of the car of FIG. FIG. 3 is a schematic diagram of one embodiment of the vehicle speed control system of the present invention including a cruise control system and a low-speed progress control system. FIG. 4 is a flow diagram illustrating the interaction between the cruise control system of FIG. 3 and the low speed travel control system. FIG. 5 is a schematic view of still another feature of the vehicle speed control system of FIG. FIG. 6 is an exemplary view of a steering wheel, a brake, and an accelerator pedal of a vehicle according to an embodiment of the present invention. FIG. 7 is a plot of a vehicle pedal output signal S as a function of pedal travel distance d according to one embodiment of the present invention. FIG. 8 is an illustration of a vehicle according to an embodiment of the present invention that climbs at two different positions, each with a different slope. FIGS. 9 (a)-(d) are plot diagrams illustrating specific parameters of a vehicle as a function of time at different off-road driving conditions, illustrating the operation of a vehicle speed control system according to one embodiment of the present invention. FIGS. 9 (e) and (f) are plots illustrating specific parameters of the vehicle as a function of time at different off-road driving conditions, illustrating the operation of the vehicle speed control system according to one embodiment of the present invention. FIG. 10 is a plot showing powertrain torque and braking torque over a portion of the course of an off-road driving example as a function of time for a vehicle according to one embodiment of the present invention. FIG. 11 is a plot showing powertrain torque and braking torque over time for a portion of an off-road driving course of a vehicle according to an embodiment of the invention as a function of time. FIG. 12 is a plot showing the vehicle speed v, the set speed vset, and the traction control system flag state over a portion of the course of an off-road driving example of the vehicle according to an embodiment of the present invention as a function of time. FIG. 13 is a plot diagram showing vehicle speed v, set speed vset, and traction control system flag state over a portion of the course of an off-road driving example of a vehicle according to another embodiment of the present invention as a function of vehicle travel distance. is there. FIG. 14 is a plot showing powertrain torque, vehicle speed, and set speed over a portion of the course of an off-road driving example of a vehicle according to an embodiment of the present invention as a function of vehicle travel distance. FIG. 15 is a plot showing powertrain torque, vehicle speed, and set speed over a portion of the course of an off-road driving example of a vehicle according to an embodiment of the present invention as a function of vehicle travel distance. FIG. 16A is an exemplary view of a console incorporated in a vehicle according to an embodiment of the present invention, and FIG. 16B is a plan view of a cabin of the vehicle according to an embodiment of the present invention.

  A reference to a block, such as a function block, shall include a reference to software code that performs a function or operation that is defined as providing an output in response to one or more inputs. The software code may be in the form of a software routine or function that is called by the computer main program, or may be code that forms part of the flow of code that is not another routine or function. The function block is referred to in order to simplify the explanation of the operation manner of the controller.

  The embodiment of the present invention is suitable for use in a vehicle equipped with an automatic or continuously variable transmission. FIG. 1 shows a vehicle 100 having a powertrain 129 according to one embodiment of the present invention. The powertrain 129 includes an engine 121 connected to a drive line 130 having a transmission 124. The drive line 130 is configured to drive the front wheel pair 111, 112 by the front differential 137 and the front drive shaft pair 118. The drive line 130 includes an auxiliary drive line portion 131 configured to drive with an auxiliary drive shaft or propeller shaft 132 configured to drive the rear wheel pair 114, 115, a rear differential 135, and a rear drive shaft pair 139. Is also included. In the embodiment of the present invention, a transmission has a configuration in which only a front wheel pair or only a rear wheel pair (that is, a front wheel drive vehicle or a rear wheel drive vehicle) is driven, or two-wheel drive / four-wheel drive switching. It is suitable for use in a vehicle having a free configuration. In the embodiment of FIG. 1, the transmission 124 can be releasably coupled to the auxiliary drive line 131 by a power transmission unit (PTU) 131 that enables two-wheel drive or four-wheel drive switching. Embodiments of the present invention may be suitable for vehicles having four or more wheels, or vehicles where only two wheels, for example, a three-wheel vehicle, a four-wheel vehicle, or a four-wheel or more vehicle are driven.

  The control system for the car engine 121 includes a central controller referred to as the vehicle control unit (VCU) 10. The VCU 10 receives and outputs a plurality of signals input / output to / from various sensors and subsystems (not shown) mounted on the vehicle. VCU 10 includes a low speed travel (LSP) control system 12 and a stability control system (SCS) 14, the latter being a known component in existing vehicle control systems. The SCS 14 detects and reduces traction to increase vehicle safety. When a loss of steering wheel control is detected, the SCS 14 automatically applies the brake to assist the user in steering the vehicle in the desired direction.

  Although not shown in FIG. 3, the VCU 10 further includes a dynamic stability control (DSC) function block, a traction control (TC) function block, an antilock braking system (ABS) function block, and a downhill control (HDC) function block. Including. These function blocks provide, for example, outputs indicating DSC, TC, ABS activities, braking interventions at each wheel, and engine torque reduction requests from the VCU 10 to the engine 121. All of the events described above represent wheel slip events. A vehicle subsystem such as a roll stability control system or others may also be beneficial.

  The vehicle also includes a cruise control system 16 that operates to automatically maintain the vehicle speed at a selected speed when traveling at a speed of 30 mph (about 48.2 km / h) or higher. The cruise control system 16 is provided with a cruise control HMI 18 that allows a user to input a target vehicle speed into the cruise control system 16 in a known manner. In one embodiment of the present invention, a cruise control system input control device is mounted on the steering wheel 171.

When the “speed setting” control device 173 is pressed, the current vehicle speed is set to the set speed. Pressing the “+” button 174 increases the setting speed, and pressing the “−” button decreases the setting speed.
The cruise control system 16 monitors the vehicle speed, and the deviation from the target vehicle speed is automatically adjusted so that the vehicle speed is maintained at a substantially constant value, typically 30 mph (about 48.2 km / h) or more. In other words, the cruise control system does not function at vehicle speeds below 30 mph (about 48.2 km / h). The cruise control HMI 18 may also be configured to provide a warning regarding the status of the cruise control system to the user via the visible display of the cruise control HMI 18.

  The LSP control system 12 provides the user with a speed-based control system that allows the user to select a very low target vehicle speed at which the vehicle can travel without the need for pedal input by the user. This low-speed progress control function is not provided by the on-highway cruise control system 16 that operates only at a vehicle speed of 30 mph (about 48.2 km / h) or higher. Furthermore, the known on-highway cruise control system including the system 16 has a manual operation in which the cruise control function is disabled when the user steps on the brake or clutch, and the vehicle requires the user's pedal input to maintain the vehicle speed. Configured to return to mode. In addition, detection of wheel slip events, such as may occur due to loss of traction, has the effect of interrupting the cruise control function.

  LSP control is implemented by adding selective powertrain, traction control and braking action to all or individual wheels to maintain the vehicle speed at the desired speed. The user inputs a desired target vehicle speed to the LSP control system 12 via a low speed traveling HMI (LSP HMI) 20. The LSP control system 12 typically operates at a vehicle speed of about 50 mph (about 80.4 km / h) or less, but is activated until the vehicle cruise control system becomes ineffective 30 mph (about 48.2 km / h) or less. Not. The LSP control system 12 is configured to operate independently of traction events such as wheel slip and at least in that respect differs from the functionality of the cruise control system 16 as described in detail below.

The LSP HMI 20 is provided in the cabin of the car. A vehicle user can input a desired vehicle speed (referred to as “target vehicle speed”) to the LSP control system 12 via the LSP HMI 20 and the signal line 21.
The LSP HMI 20 also includes a visual display (not shown) that can provide a warning to the user regarding the status of the LSP control system 12.

  The LSP control system 12 receives an input representing the amount of depression of the brake pedal 163 by the user from the vehicle brake system 22. The LSP control system 12 further receives an input from the accelerator pedal 161 of the vehicle that represents the amount of depression of the accelerator pedal 161 by the user. The LSP control system 12 is also provided with inputs provided from the transmission or gearbox 124 and any associated control means not shown. This input may include, for example, a signal representing the output shaft speed from the gearbox 124, torque converter slip, and the required gear ratio. Other inputs to the LSP control system 12 include an input from the cruise control HMI 18 that represents the state (ON / OFF) of the cruise control system 16 and an input from the LSP HMI 20 that represents the state of the LSP control function. The cruise control HMI 18 and the LSP HMI 20 are typically installed on or adjacent to the steering wheel so as to be easily operated by the user.

  The cruise control HMI and the LSP HMI are arranged next to each other in the cabin of the car and are preferably mounted on the steering wheel for easy operation by the user. In FIG. 4, the interaction between the cruise control HMI 18 and the LSP control system 12 is shown in a flow diagram. When the user attempts to activate the LSP control system 12 via the LSP HMI 20, a signal is sent to the cruise control system 16 that cancels the speed control routine. Then, the LSP control system 12 is activated, and the vehicle speed is maintained at the low target vehicle speed selected by the user via the LSP HMI 20. Activation of the cruise control system 16 may be prevented when the LSP control system 12 is activated. Therefore, the LSP control system 12 and the cruise control system 16 operate independently of each other, and only one of them can operate at a time according to the traveling vehicle speed.

  In another embodiment, the cruise control HMI 18 and the LSP HMI 20 are included in the same hardware so that the selected speed is input through the same hardware provided with a switch for switching between the LSP input and the cruise control input, for example. Can be configured.

  FIG. 5 illustrates vehicle speed control means of the LSP control system 12. The vehicle speed selected by the user is input to the LSP control system 12 via the LSP HMI 20. A vehicle speed sensor 34 associated with the engine provides a signal 36 representing the vehicle speed to the LSP control system 12. The LSP control system 12 includes a comparator 28 that compares the target vehicle speed 38 selected by the user with the measured vehicle speed 36 and provides an output signal 30 representative of this comparison. The output signal 30 is provided to the evaluator unit 40 of the VCU 10, which determines whether a torque addition request to be applied to the wheel depends on whether the vehicle speed needs to be increased or decreased to maintain the vehicle speed selected by the user. Alternatively, the output signal 30 is interpreted as a torque reduction request.

  The output 42 from the evaluator unit 40 is provided to the drive lines for the wheels 111-115, thus increasing or decreasing the additional torque on the wheels based on whether the torque request from the evaluator unit 40 is positive or negative. In order to execute the required torque addition to the wheel by either increase or decrease, the evaluator unit 40 can execute the torque change necessary for maintaining the target vehicle speed using either or both of them, Any of adding braking force can be commanded. In the exemplary embodiment, torque is applied individually to the wheels to maintain the target vehicle speed, but in other embodiments, torque can be applied to all wheels to maintain the target vehicle speed.

  The LSP control system 12 also receives a signal 48 representative of a wheel slip event. The signal 48 can be the same as that supplied to the car's on-highway cruise control system 16, but in the latter case the operation of the on-highway cruise control system 16 is disabled or prevented by this signal, and the on-highway type The vehicle speed automatic control by the cruise control system 16 is interrupted or canceled. However, the LSP control system 12 is not configured to cancel or interrupt its operation upon receipt of a signal 48 indicative of wheel slip, but rather monitors wheel slip and keeps the driver's workload to a minimum. Configured to handle wheel slip. During the occurrence of the slip event, the LSP control system 12 continues to compare the measured vehicle speed with the desired vehicle speed entered by the user and continues to automatically control the torque to be applied to the wheels so that the selected vehicle speed is maintained. As described above, the LSP control system 12 has a different configuration from the cruise control system 16 in which the manual operation of the vehicle is resumed because the cruise control function is invalidated due to the wheel slip event, or the cruise control function is reset. Have.

  In yet another embodiment of the invention (not shown), the vehicle is provided with a wheel slip signal 48 that is not only obtained by comparing wheel speeds, but also more accurately using sensor data representing ground vehicle speed. Is done. The ground vehicle speed can be determined via global positioning system (GPS) data or vehicle-mounted radar or a laser system having a configuration for determining relative movement between the vehicle and the vehicle's travel location.

  At any stage of the LSP control process, the user can disable or increase the function of the process by increasing or decreasing the vehicle speed with the accelerator and / or brake. However, if a wheel slip event is detected via signal 48, LSP control system 12 will not operate to interrupt the LSP process. As shown in FIG. 5, the wheel slip event signal is then provided to the LSP control system 12 and processed by the LSP control system 12 without interrupting or otherwise disabling the LSP control process.

  A wheel slip event occurs when any one of the wheels loses traction. Wheels and tires are more susceptible to loss of traction, for example, on snow, ice, or sand, or in much rougher or slippery terrain than when driving on highways in normal on-road conditions it is conceivable that. Therefore, the present invention is useful when driving a vehicle in an off-road environment or under conditions where the wheels are generally likely to slip, or when the user's manual operation is difficult and often results in a stressful experience, and the ride comfort can deteriorate. However, according to the present invention, it is possible to continuously run at a low target vehicle speed without requiring user intervention. The present invention is also beneficial when used in low-speed traffic congestion conditions because user fatigue due to repeated start / stop pedal operations is reduced.

  The LSP control system 12 does not operate at a vehicle speed exceeding a predetermined threshold speed for 30 mph (about 48.2 km / h), for example. Therefore, for example, when the vehicle is traveling at 30 mph (about 48.2 km / h) or more and the user selects the LSP control system 12, a warning that the LSP control system cannot be activated is displayed via the LSP HMI 20. The However, when the vehicle speed becomes 30 mph (about 48.2 km / h) or less, the LSP control system 12 is automatically started without the user having to reselect the LSP control. In other words, the LSP control system 12 is held in a standby state until the vehicle speed is reduced to a level equal to or lower than the threshold speed.

  When the user operates the LSP HMI 20 to start the LSP control system 12 while the vehicle is traveling at a speed between the first threshold speed on the low speed side and the second threshold speed on the high speed side, The system records the user's desire to start LSP control, but may be configured not to start LSP control until the vehicle speed is decelerated to a level below the first threshold speed on the low speed side.

  In yet another embodiment of the invention (not shown), the vehicle is provided with an on-board detection system, such as a radar system or other range detection means, which monitors the front obstacle or the preceding vehicle of the vehicle. Then, the feedback information from the radar system is used to maintain a safe distance to the preceding vehicle.

  The car is also equipped with additional sensors (not shown) that display various different parameters related to the movement and condition of the car. They can be from inertial systems inherent in the speed control system, or part of the occupant restraint system, or sensors such as gyroscopes or accelerometers that can display vehicle movement and provide useful input to the LSP control system 12. It can be any other subsystem that can provide data. The signal from the sensor is used to provide or calculate a plurality of driving condition indicators (also referred to as terrain indicators) that represent characteristics of the vehicle's traveling terrain conditions. This signal is sent to the VCU 10, which determines the optimum control mode for the various subsystems based on the terrain indicator and automatically controls the subsystem according to those modes. Details of aspects of the present invention are described in GB 111128.55, GB1211910.3, GB1202427.9, the applicant's continued patent applications, which are hereby incorporated herein by reference. .

  Vehicle sensors (not shown) include, but are not limited to, sensors that provide a continuous sensor output to the VCU 10, including the wheel speed sensors described above and shown in FIG. Ambient temperature sensor, atmospheric pressure sensor, tire pressure sensor, car yaw, roll, gyroscope sensor that detects pitch angle and pitch rate, vehicle speed sensor, longitudinal acceleration sensor, engine torque sensor (or engine torque estimator), steering wheel Rudder angle sensor, steering wheel speed sensor, tilt sensor (or tilt estimator), lateral acceleration sensor on stability control system (SCS), brake pedal position sensor, accelerator pedal position sensor, front / rear, lateral, longitudinal motion sensor, In particular, it includes a water detection sensor that forms part of a car crossing support system (not shown). .

  In other embodiments, only selected ones of the aforementioned sensors may be used. The VCU 10 also receives a signal from the vehicle's electrically assisted steering unit (ePAS unit) that displays the additional steering force on the wheels (the steering force applied by the user combined with the steering force applied by the ePAS system).

  The VCU 10 evaluates various sensor inputs to determine the appropriateness of the control mode corresponding to the specific terrain type (eg, mud and dredging, sand, grass / gravel / snow) that the vehicle travels for the vehicle subsystem. The VCU 10 then selects the optimal control mode and controls various vehicle parameters according to this mode.

  The terrain characteristic on which the vehicle travels can also be used when determining appropriate increase / decrease of the additional driving torque to the wheels in the LSP control system 12. For example, if the user selects a target vehicle speed that is not suitable for the terrain characteristics on which the vehicle is traveling, for example for safety reasons, the system is activated to reduce the wheel speed and thus automatically adjust the vehicle speed to a low speed. When the system selects a speed that is different from the target vehicle speed selected by the user, a speed limit visual indication is provided to the user via the LSP HMI 20 indicating that another speed has been adopted.

1. A-315 Set Speed Control by Brake and / or Accelerator Control According to one aspect of the present invention, the speed control system is a control means that is operable to maintain the set speed of the vehicle, so that the user can control the braking of the vehicle. A speed control system is provided that includes control means operable to allow the set speed to be reduced by operating the device.

  By car braking control device is meant a control device by which a user can apply a basic braking system. The braking control device may include a brake pedal, for example. The basic brake system may include a friction brake system and optionally a regenerative brake system. In some embodiments, the basic brake system may include a regenerative brake system instead of or in addition to the friction brake system.

In conventional cruise control systems for highway driving, the control device that changes the set speed of the cruise control system is typically “+/−” mounted on or adjacent to the steering wheel of the car. Provided with a button configuration. When the car is traveling in off-highway conditions, the user may be required to turn the steering wheel relatively quickly and / or at a relatively large steering angle while passing through difficult terrain. Therefore, it may be difficult for the user to operate the “+/−” buttons simultaneously. Furthermore, the user may accidentally press another button that changes the set speed. Embodiments of the present invention have the advantage that control by means that can change the set speed can be provided separately from the steering wheel. Also, since the control for changing the set speed can be performed with the foot rather than the user's hand, the user's hand is free to continue driving the car.
By reducing the set speed with the brake pedal, a relatively straightforward means for allowing the user to change the set speed can be provided.

  In some embodiments, the speed control system may operate such that speed control of a set speed on an off-highway can be enabled or disabled by a user brake and / or accelerator control. This functionality can be provided by an HMI display or otherwise.

  In an embodiment of the present invention, the control means may reduce the set speed by the user applying a force within a predetermined range or transmitting a control of a movement amount within the predetermined range to operate the braking control device. Can be freely operable. The range of pressure or travel required to reduce the set speed is less than that required when applying the basic brake system. That is, the range may be within the “dead zone” range of pressure or stroke.

  Alternatively, the range may include a value sufficient to cause a basic brake system application. In certain embodiments, where the range includes a value sufficient to cause basic brake system operation, when the user applies a pressure or travel within a predetermined range sufficient to apply the basic brake system, the speed control system may: It is possible to operate so as to compensate for the addition of braking torque when applying the basic brake system by adding the increased torque by the power train. Other configurations are also useful.

The predetermined pressure range value may be a value from the first pressure value to the second pressure value that are both greater than zero. In one embodiment, the predetermined range value may be a value up to a first pressure value that is greater than or equal to zero and less than or equal to a second pressure value that is greater than zero.
According to yet another aspect of the present invention, a speed control system is provided that is a control means operable to control a vehicle to maintain a set speed, wherein a user operates an acceleration control device of the vehicle. A speed control system is provided that includes control means that can increase the set speed.
The acceleration control device includes, for example, an accelerator pedal.

  The control means may be operable so that the user can increase the set speed by operating the acceleration control device with a pressure within a predetermined range or a movement amount within a predetermined range. The pressure or movement amount range required for increasing the set speed may be smaller than that required for increasing the power train generation power amount. That is, the range may be within a “dead zone” range of force or stroke. Alternatively, the range may include a value sufficient to increase the amount of power train generation power. In some embodiments, where the range includes a value sufficient to increase the amount of power train generated power, when a user applies a predetermined range of force or travel within a predetermined range sufficient to increase the power train torque, The control system may operate to compensate for the increased torque applied by the powertrain by applying the basic brake system. Other configurations are also useful.

Beneficially, the system may be further operable to allow a user to actuate a braking control device such as a car brake pedal to reduce the set speed.
Optionally, the control means applies the pressure having a value within a predetermined range by the user and / or operates the braking control device for a time longer than the predetermined time with a movement amount within the predetermined range. Can be configured to gradually decelerate the set speed within a predetermined range in incremental steps over the length of time for which the braking control device is to be activated.

  If the user activates the braking control device with pressure and / or travel greater than the predetermined range, the speed control system is operable to cancel the speed control mode and apply the basic brake system in a conventional manner. is there. Thus, in a vehicle equipped with a speed control system according to the present invention, the basic brake system operates independently of the speed control system so that the vehicle response to the brake controller input is the same regardless of the speed control mode selected. Can be configured as follows. Thus, in one embodiment of the present invention, whenever the pressure or travel of the braking controller exceeds a predetermined value, the standard acceleration and braking controller input takes precedence over the automatic control system or control means, and the user behavior is the speed. The speed control is canceled when the control device indicates a cancellation request.

In an embodiment, the pressure and / or movement amount above a predetermined range to which the basic brake system is applied corresponds to the pressure and / or movement amount above the predetermined range to which the basic brake system is applied when the speed control device is not selected. Can do. This feature is beneficial in that the basic brake system response experienced by the user to the brake controller input is the same regardless of the speed control mode selected.
In some embodiments, the dead zone that appears in braking and / or acceleration controlled runs may be deliberately increased if the off-highway speed controller is operable.

  In some embodiments, the speed control system (or any other braking control device, etc.) detects that the rate of movement of the brake pedal or the rate of increase of the applied pressure to the brake pedal is above a predetermined rate even within the dead band range. If so, the application of the car brake system can be commanded. This feature is beneficial in that the speed at which the brake system can respond to emergency braking control inputs can be increased.

The system is advantageous in that it is further operable so that the user can operate the vehicle acceleration control device to increase the set speed.
The speed control system is beneficial in that it can operate in off-highway and highway conditions. An off-highway (or “off-road”) condition can be referred to as a progress control system or a slow progress control system. On-highway conditions can be referred to as a cruise control system. Other configurations are also useful.

  Optionally, the speed control system is operated by the user on the vehicle braking control device to reduce the set speed (and optionally, the user operates the vehicle acceleration control device only when operating in off-highway conditions. The set speed can be increased). Alternatively, when the speed control system operates under either an off-highway condition or a highway condition, for example, a low-speed traveling control condition or an on-highway cruise control condition, the user operates the vehicle braking control device to reduce the set speed ( And optionally, it can be actuated so that the user can actuate the vehicle acceleration control to increase the set speed. Embodiments of the present invention are also suitably used in vehicles that are not equipped with off-highway operating conditions or on-highway cruise control systems.

The set speed control by the brake controller and / or the acceleration controller may be configured to occur only in the off-highway speed controller in some embodiments.
According to one aspect of the present invention, a method for controlling the speed of a vehicle is provided, which includes the step of automatically reducing the set speed of the vehicle based on the operation of the braking control device of the vehicle by a user.

  According to another aspect of the present invention, there is provided a method for controlling the speed of a vehicle, the method including automatically increasing a set speed of the vehicle based on the operation of a vehicle accelerator by a user.

According to yet another aspect of the present invention, a speed control method for a vehicle is provided, the method comprising automatically reducing a set speed of a vehicle independently of a user's operation of a braking control device of the vehicle; Automatically increasing the set speed of the vehicle independently of the operation of the acceleration control device of the vehicle.
In some embodiments, the speed control system is operable to change the gear ratio of the transmission so that when the set speed is reduced, sufficient drive torque is obtained to pass through the obstacle. . The speed control system may be operable to increase the gear ratio.

Thus, in some configurations, if the user reduces the set speed, the engine speed can be increased if the set speed drops below a predetermined value of, for example, 5 km / h or any suitable speed. Setting speed reduction may mean a user's intention to deal with obstacles such as large rocks, steep slopes or others.
The user can change the set speed of the speed control system by giving a relatively light pedal input, so that the user does not need to manually operate the speed setting control device on the steering wheel, and the vehicle is operated at a low speed (for example, 50 km / h or less). Off-road driving can be performed. This reduces the amount of user work and makes the vehicle operation more straightforward when the speed control device is active. Embodiments of the present invention also make it possible to organize a switch pack on or around the steering wheel, or in addition, to organize a vehicle steering control device. In some scenarios, it is important not to distract the user from the terrain where the car travels. For example, the user experience can be improved by eliminating the need for the user to concentrate attention in the vehicle when operating the control device using the hand or finger in the vehicle to change the set speed.

  In some embodiments, the user initiates speed control, the car runs below a threshold speed, and / or the car enters an off-road driving mode (eg, by terrain response (TR) mode selection or low gear ratio selection). If set, or otherwise, it is determined that the vehicle is operating off-road, the speed control system operates in off-road conditions (or modes) and the speed control device is maintained in an active condition. In the meantime, a set speed adjustment command is received via a braking and / or acceleration control device such as a brake and / or an accelerator pedal as described above.

  In some embodiments, it is displayed when the user initiates speed control, the car is running above a predetermined speed, and / or the car is driving on the road (selecting a “high” gear ratio as opposed to a “low” gear ratio) Or if the terrain response (TR) mode is released (in some embodiments, the “special program off” TR mode is selected), the speed control system typically represents the steering wheel of the car. Only speed regulation by a manually operated control device positioned above or adjacent to can be accepted. If the user depresses the brake pedal during speed control operation (on-road or on-highway conditions), the speed control operation will be interrupted even if the pedal is lightly depressed, and the vehicle will be depressed by the user depressing the accelerator pedal or via a manual operation switch. Start coasting until the speed controller is restarted.

In one embodiment, the user adjusts the vehicle speed by either depressing the brake pedal (to reduce the set speed) or depressing the accelerator pedal (to increase the set speed) while driving under off-highway speed control conditions. it can.
According to one aspect of the present invention, a speed control system includes control means operable to maintain a set speed of an automobile, said control means being set by a user operating a foot pedal. A speed control system is provided that includes control means operable to vary the speed. The system may be operable so that the user operates the brake pedal to reduce the set speed. Additionally or alternatively, the system may be operable so that the user operates the accelerator pedal to increase the set speed.

  Embodiments of the present invention will be described below with reference to the accompanying drawings only. FIG. 6 shows details of the steering wheel 171 of the car 100 of FIG. 1 along with the accelerator and brake pedals 161 and 163. As in conventional vehicles, the steering wheel 171 has a “set speed” controller 173 that can be activated by the user to activate the speed control system to maintain the current speed of the car. The steering wheel 171 also has an “LSP” controller activation button and a resume button. The resume button can be used to control both the “on highway” cruise control system during on-road driving and the LSP control system 12 during off-road driving. The LSP control button is used to activate the LSP control system 12, and the resume button is used to command the LSP control system 12 to control the vehicle 100 to resume the previously set (user defined) speed.

  In yet another embodiment of the present invention (not shown), the LSP control system 12 is provided with a memory configured to store a previously set user-defined set speed in addition to the last set speed set by the user. It is done. Thus, the user has immediate access to one or more set speeds via a resume button or other suitable control device. In this embodiment, the user can drive the vehicle at a set speed of 10 mph (about 16.0 km / h), but the speed is increased to 6 mph (about 9.6 km / h) to cope with an off-road with an obstacle. Can be selected. Since the LSP control system 12 is configured to store both 6 mph (about 9.6 km / h) and 10 mph (about 16.0 km / h), the LSP control system 12 intervenes to further increase the speed to 4 mph (about 6 mph). The system is configured to accelerate to 6 mph (about 9.6 km / h) by pressing the resume button once, or to 10 mph (about 16.0 km / h) by pressing twice when the speed is reduced to 4 km / h. Can request. The LSP control system 12 may be provided with a means for displaying the stored set speed to the user by, for example, an illumination mark or a chapter arranged at an appropriate position around the speedometer. In one example, the LSP control system 12 accesses a preset speed from memory and applies this speed if it is determined that the speed is too high for the terrain on which the car is currently driving. Can be configured to prevent alone or in combination with TR mode setting. Instead, the LSP control system 12 may be configured to accelerate to the highest speed determined to be appropriate for the terrain and continue to accelerate toward the selected set speed as the terrain permits. In this example, the LSP control system 12 manages vehicle acceleration within a predetermined acceleration corridor, for example, 0.1 to 0.2 g. The LSP control system 12 may be provided with means for displaying the current state to the user so that the LSP control system 12 resumes the speed when the user-defined set speed becomes appropriate for the terrain. Operate. The LSP control system 12 is configured such that a user can disable the LSP control system 12 at any time in the manner previously described.

  When the set speed control device 173 is pressed while the vehicle is traveling on the highway, the cruise control system 16 is activated when the current vehicle speed is 50 km / h or higher. The cruise control system 16 increases the set speed when the “+” control device 174 is pressed, and decreases the set speed when the “−” control device 175 is pressed. Each of the “+” and “−” control devices can be a single button.

  When the set speed control device 173 is pressed while the vehicle is traveling on an off-highway, the LSP control system 12 is activated and operated as described above. The system may further include a “cancel” button operable to cancel speed control by the LSP control system 12. In some embodiments, the LSP system is either in an active state or in a standby state. In some embodiments, the LSP system 12 is suspended from vehicle speed control by the LSP control system 12, but the downhill control (HDC) system and others take intermediate states that can remain active if already activated. It can be actuated. Other configurations are also useful.

  When the LSP control system 12 is active, the user can increase or decrease the vehicle speed using the “+” and “−” buttons 174 and 175. In addition, the user can also increase or decrease the set vehicle speed by stepping on the accelerator pedal 161 or the brake pedal 163 lightly. In other embodiments, the “+” and “−” buttons 174, 175 are disabled when the LSP control system 12 is active.

  FIG. 7 is a plot of pedal output signal s as a function of travel d, which is the amount of pedal 161, 163 depression (eg, measured by linear travel, angular rotation, or full scale deviation) of the accelerator or brake pedal. It is. In the configuration shown, the pedal output signal increases in a substantially linear fashion as a function of travel, but other configurations are also useful. The brake system 22 is activated in response to the pedal output signal, the vehicle 100 is braked, the VCU 10 is activated, and the amount of torque generated by the engine 121 changes. In the present embodiment, the brake system 22 is configured such that the vehicle is not braked and the VCU 10 does not change the amount of torque generated by the engine 121 until the amount of pedal movement exceeds the threshold distance d2 illustrated in FIG.

  The LSP control system 12 is operable to monitor pedal input signals from the accelerator and brake pedals 161,163. When the pedal movement amount satisfies the condition d1 ≦ d ≦ d2 when d1> 0, the LSP control system 12 operates to increase or decrease the LSP control system set speed. The LSP control system 12 increases the set speed when the accelerator pedal movement amount satisfies the condition, and decreases the set speed when the brake pedal movement amount satisfies the condition.

In some embodiments, one or both of the d1 and d2 values for each of the accelerator and brake pedals 161, 163 may be different.
In some embodiments, if the vehicle 100 is lowered using a "-" button or other control device rather than a brake control device, the speed control system may at least first apply the brake system or other braking torque means. Rather, the vehicle speed is reduced by coasting, and the brake system is applied only when the speed control system determines that it is necessary. In contrast, if the set speed is reduced with a braking control device such as a brake pedal 163, in some embodiments at least a light braking force may be provided while the brake pedal 163 is depressed. Thus, when the brake pedal 163 is depressed, the set speed decrease due to the brake pedal 163 is applied immediately after the brake control torque is judged not by the speed control system to determine the necessity of the brake torque to be reduced to the new set speed of the user. The vehicle speed can be reduced much faster.

The “+” or “−” control device is not limited to the control device represented by these symbols. Rather, the “−” control device may include a control device other than the braking control device that decreases the set speed, and the “+” control device may include a control device other than the acceleration control device that increases the set speed. The “+” and “−” control devices can be manually operated by the user, for example.
Embodiments of the present invention can increase the enjoyment of a user traveling a vehicle on off-highway conditions.

2. A-316 Haptic feedback According to one aspect of the present invention, a speed control system includes control means operable to control a set speed of an automobile, said control means enabling a user to activate a control device. In response to the user, and the system provides haptic feedback to the user in response to the user operating an amount sufficient to cause the controller to change the set speed. A speed control system operable to provide is provided.

  Advantageously, the control device comprises a foot operated pedal. In one embodiment, the pedal is operable to provide haptic feedback only when the vehicle is in an off-highway or off-road speed control condition or mode. Under such conditions, the speed control system allows the vehicle to move at a relatively low set speed (such as a speed in the range of 5-10 km / h) even when one or more wheels slip due to loss of traction. , A speed of less than 50 km / h) can be maintained. For example, in one embodiment, the off-road speed control system may continue to operate even when a sufficient amount of wheel slip occurs to operate a vehicle stability control system or the like. Conventional on-highway speed control systems are limited to operation at minimum speeds (typically about 50 km / h) and are automatically canceled upon detecting sufficient wheel slip to intervene the stability control system.

  In some embodiments, the speed control system is configured to cancel the automatic speed control when the user operates the controller or applies pressure beyond the position range (“haptic” zone). Therefore, the vehicle speed control is returned to the user side. The haptic feedback provided by the speed control system may have a different configuration so that the user can easily distinguish this feedback from that associated with anti-lock braking system (ABS) operation. Haptic feedback can provide, for example, pulses, vibrations and / or sounds of different amplitude and / or frequency than those involved in ABS operation.

  Additionally or alternatively, in some embodiments, a haptic zone can be identified by an increase in resistance to pedaling when the user applies pressure to the brake pedal or applies force to the accelerator pedal. The resistance increase can be provided throughout the haptic zone. In some embodiments, the resistance can be increased before the amount of pedal movement or the amount of pressure or force applied to the pedal is sufficiently large to be outside the haptic zone.

  In some embodiments, one or more clicks, tones or pulses may be generated when the controller enters the haptic zone. In response to controller operation within the haptic zone with speed control system operation, the user may also be provided with HMI (Human Machine Interface) feedback. In some embodiments, haptic feedback regarding the set speed change may be provided only when a speed control system is activated that can be used by the controller for the set speed change.

  Embodiments of the present invention are beneficial in that the user does not need to use a brake or accelerator pedal to continue traveling across the terrain. Rather, an off-highway speed control system may automatically control the powertrain and brake system to maintain progress. In some embodiments, the off-highway speed control system may operate to cancel when the brake pedal is depressed more than a predetermined amount.

  According to the present invention, while the speed control system is operated under the off-highway speed control condition, the brake system of the vehicle is applied when the brake pedal is stepped on at a predetermined applied pressure or an amount equal to or less than the movement amount, although not zero. And the set vehicle speed associated with the speed control system is reduced without canceling off-highway speed control conditions. This is particularly beneficial when the pedal is not disconnected from the basic braking system or otherwise disconnected when the off-highway speed control function is activated. Other configurations are also useful. In an embodiment, the set vehicle speed is increased when the accelerator pedal is stepped on by an amount that is greater than or equal to 0 but less than or equal to a predetermined applied pressure or travel.

As noted above, in some embodiments, the set vehicle speed change when the foot pedal is depressed may be configured to occur only when the vehicle is operating in off-highway speed control conditions or modes.
Certain embodiments of the present invention are beneficial in that the user notices that the car is in an off-highway condition when depressing the brake pedal. When the user fully depresses the brake pedal with a large amount of travel or applies a sufficiently high pressure, the pedal "pushes" through the haptic zone, thus interrupting / cancelling the off-road speed control mode.

It may be difficult to know the pressure to press the brake pedal or the force applied to the accelerator pedal to change the set speed when traveling on rough terrain. Thus, with haptic feedback, the user can actively determine that the amount of pressure applied to the brake pedal (and / or the force on the accelerator pedal) is sufficient to change the set speed.
The haptic feedback may be provided to the user by a foot operated pedal (such as a brake or accelerator pedal) that the user steps on, a steering wheel, a user seat, or any other means suitable for the user to experience the haptic.

The embodiment of the present invention has a feature that allows the user to determine the degree to which the brake and / or accelerator pedal are pressed to change the set speed of the speed control system without canceling the off-road speed control condition.
Exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in particular FIG. When the user depresses the brake pedal 163 in the movement range of d1 to d2 such that the value of the pedal output signal is in the range of s1 to s2, the LSP control system 12 is activated to lower the set speed selected by the user, In addition, vibration excitation is applied to the brake pedal 163 to provide haptic feedback to the user. When the brake pedal output signal s is in the range of s1 to s2 for less than a predetermined time length (such as 1 second), the set speed value is a predetermined amount (in this embodiment, 1 km / h or 1 mph based on the unit selected by the user). Is lowered. When the brake pedal output signal s is in the range of s1 to s2 for a predetermined time length (1 second or longer in this case), the set speed is, for example, 500 milliseconds or every 1 km / h or 1 mph step every other time Will be reduced. Alternatively, the reduction rate can be set at an arbitrary rate. Other configurations are beneficial, and other time lengths are beneficial. The LSP control system 12 is configured such that the brake pedal 163 needs to be pressed for a longer period of time (which can be any suitable value, for example 100 milliseconds) until the set speed is reduced. obtain.

  Conversely, when the accelerator pedal 163 is depressed so that the accelerator pedal output signal is in the range of s1 to s2, the set speed value is increased. In one embodiment, if the accelerator pedal output signal is in the range of s1 to s2 for a predetermined time length or longer, the set speed is 1 s, for example, 1 km / h or 1 mph every 500 milliseconds or other time lengths. Increased in steps. Alternatively, the speed increase rate can be set to an arbitrary rate. Other configurations are also useful. The LSP control system 12 has a configuration that requires the accelerator pedal 161 to be pressed for a longer period of time (which can be any suitable value, for example 100 milliseconds) until the set speed is increased. obtain.

3. A-317 Automatic torque balancing based on force acting on the vehicle to accelerate or decrease the vehicle during off-road speed control traveling, for example, braking torque due to uphill gradient or acceleration force due to downhill gradient According to an aspect, a speed control system operable under off-highway conditions, wherein the speed control system controls a means for applying torque to at least one of a plurality of wheels of the vehicle to maintain a predetermined set speed on the road Is provided. The system may be operable so that the user can increase or decrease the current set speed to the target set speed. Thus, when the user requests to change the set speed, the speed control system can control the torque applying means in such a way that the car can automatically accelerate (on the positive / negative side) to the new set speed.
The torque applying means may include a power train and optionally a brake system, described in detail below.

  When changing the vehicle speed to match the newly set speed, the system may be operable to detect and take into account external forces acting on the vehicle to accelerate (on the positive / negative side) the vehicle. The speed control system compensates for an external force that is present when changing the amount of required additional torque applied to one or more wheels, and reduces the risk of overshooting the new target set speed. In some embodiments, the system may be operable to substantially prevent new target set speed overshoots. The speed control system may be operable to control the powertrain and optionally the brake system. In some embodiments, the powertrain is relatively quick to apply negative torque to one or more wheels without the need to place a friction brake system, such as by one or more electric machines operating as a generator. Means may be included.

  The external force acting on the vehicle to accelerate the vehicle can be a braking torque acting on the vehicle to cause negative acceleration or a force acting on the vehicle in a manner that causes the vehicle to generate positive acceleration.

  The force acting to accelerate the car in a positive or negative manner can be a force having a component acting parallel to or along the direction of movement of the car. The force at the time of climbing the car is a braking torque because it can act in the direction opposite to the moving direction. In some embodiments, the steady direction of travel (i.e., substantially free of side skidding or yaw) may be parallel to or along the longitudinal direction of the car.

The speed control system may be operable to increase or decrease the amount of required additional torque on one or more wheels at a speed based on the magnitude of the external force. Thus, in some embodiments, as the external force (braking torque or force causing positive acceleration) increases, the torque addition amount changing speed to one or more wheels by the required torque adding means is delayed.
For example, a vehicle may receive a positive acceleration force when descending and a negative force when climbing.

  In some embodiments, the system includes, among other things, road surface gradient (see, for example, vehicle attitude), gear selection, tire friction, wheel articulation, roll resistance, vehicle selection in addition to wheel speed. Data relating to at least one selected from the terrain response mode is provided.

  In some embodiments where road surface slope information is provided, the system may include a magnitude of a force that causes the speed of changing the amount of applied torque to one or more wheels to act to accelerate or reduce the vehicle and It may be operable to be controlled based on direction.

  In one embodiment, when the vehicle receives an external force that acts to accelerate the vehicle in the positive direction in the direction of movement, the speed control system may change the additional torque amount changing speed by the torque adding means when receiving a request to increase the set speed. The speed is delayed by an amount that increases as the magnitude of the external force increases. Thus, overshoot of the (new) target set speed (vehicle speed exceeding the set speed) can be reduced or prevented. The steeper when the vehicle is descending, the greater the gravitational component that tends to cause positive acceleration, thus reducing the required acceleration torque for the means for applying torque to one or more wheels. The torque applying means may include an engine, an electric machine, or any other suitable means for applying drive torque to one or more wheels.

  In certain situations, an increase in powertrain torque may be required to accelerate the car to a new set speed within a defined acceleration corridor (eg, at a speed in the range of 0.1-0.2 g). In particularly steep situations, it may be necessary to reduce the braking torque in order to accelerate the vehicle at an acceleration value within a predetermined corridor value range. In either case, the powertrain torque and / or braking torque change rate may be configured to be delayed with increasing gradient.

  Conversely, when a force that causes positive acceleration is applied to the vehicle, the speed control system is configured to increase the amount of additional torque applied to one or more wheels as the external force increases when a set speed reduction request is made. It can be actuated to change. This is because the external force acts in a direction that hinders a decrease in the set speed.

  Speed control when the vehicle receives a certain directional force that causes negative acceleration with respect to the intended direction of movement, for example, climbing against gravity or moving through sand against the drag due to terrain structure The system maintains the vehicle acceleration within a predetermined corridor value, increases the torque application speed to one or more wheels when requesting a set speed increase, and one or one when requesting a set speed decrease. It may be operable to reduce the torque application speed to the above wheels.

  In other words, if there is a request to reduce the set speed when the car is climbing up (when braking torque is applied to the car), the system will reduce the risk that the wheel will run backward on the slope due to insufficient wheel torque to overcome the slope. It is possible to have a configuration that slows down the wheel torque reduction speed. If the wheel torque drops excessively while climbing a relatively steep hill (e.g., drops to 0), the vehicle speed may drop significantly below the new target speed, i.e., below the new target speed. is there. There are even cases where the car goes back uphill as explained earlier. Thus, the wheel torque is reduced at a much slower speed than when traveling on flat ground.

In some embodiments, when the vehicle has a set speed increase request while downhill, the system is operable to change the amount of torque applied to one or more wheels at a speed that decreases as a function of increasing slope. It can be.
In some embodiments, the vehicle may be configured to control the speed at which the wheel torque is changed in response to an amount of external force determined to act on the vehicle based on travel terrain or travel environment type. For example, terrain such as sand, mud, water or other places a relatively large braking torque on the car. At the time of water body crossing, force (in the moving direction or in the opposite direction) that accelerates or lowers the vehicle can be applied depending on whether the water body is stationary or moves in a direction having a component acting along the intended movement direction. . If a set speed reduction is required while the car is moving on a flat, sandy or muddy road surface, the system will apply to one or more wheels at a speed that decreases with increasing drag on the car. It may be operable to change the amount of additional torque to reduce the vehicle speed to a newly set speed.

  If the amount of powertrain torque decreases too early, the vehicle speed may be uncomfortable for one or more passengers due to the drag action on the vehicle, and the vehicle may stop. It can be difficult to reactivate a stopped car from a resting state.

  Conversely, when a set speed increase request is made, the speed control system may be operable to request a powertrain torque increase at a speed that increases with the amount of drag acting on the vehicle. This is because the powertrain torque needs to overcome the inertia of the car as well as the drag that tends to resist the acceleration of the car in order to achieve the new set speed.

  A vehicle according to an embodiment of the present invention is beneficial in that it can travel on terrain with higher confidence and greater comfort than a vehicle without a speed control system according to the present invention. Embodiments of the present invention can achieve a new set speed relatively quickly, regardless of the amount of force that acts against or facilitates a vehicle moving across a road surface, improving user comfort.

According to one aspect of the present invention, there is provided a speed control system capable of operating in off-highway conditions, wherein the system adds to the torque adding means a required torque for maintaining a predetermined set speed on the road. Requests to add torque to the one or more wheels to the means for applying torque to one or more wheels, the system allowing the user to increase or decrease the current set speed to the target set speed The system is configured to vary the amount of required additional torque on one or more wheels in view of external forces acting on the vehicle to accelerate the vehicle, thus providing the target set speed. A speed control system is provided that reduces overshoot or undershoot.
The torque applying means may include a power train and optionally a brake system.

  In one embodiment of the present invention, the speed control system operates in an off-highway speed control mode that accepts as an indication that the user wants to decrease while maintaining the speed control mode when the user depresses the brake pedal lightly. It may be configured to accept a strong depression of the pedal as an indication that it is desired to leave the speed control mode, and to set the set speed control to an interrupted state until restarted. Thus, the vehicle can travel off-road at a low speed (for example, 50 km / h or less) without requiring the user to touch the pedal or operating the control device on the steering wheel many times. This greatly reduces the amount of user work and increases the vehicle's clearance. When driving on rough roads, the user may support / stabilize himself / herself with his / her feet when dealing with off-road obstacles such as heels and depressions. It can be difficult.

  The off-road speed control system can constitute a part of an ATPC (All Terrain Progression Control) system, and is arranged alone or so as to optimize the configuration of the vehicle for a predetermined terrain on which the vehicle travels It may have a configuration that works in combination with one or more vehicle control systems. An example of such a system is the Terrain Response ™ system.

  In some embodiments of the speed control system of the present invention, the user initiates speed control, the car is driven below a threshold speed, and / or the car is in an off-road driving mode (eg, TR mode selection or low gear ratio selection). The speed control system operates in off-road mode and the speed control device is maintained in active mode if it is determined that the vehicle is traveling off-road. Accepts speed adjustment requests via brake pedal or accelerator pedal.

  The off-road speed control system may be provided with at least one selected from information regarding vehicle attitude, wheel speed, wheel rotation, gear selection, tire friction, roll resistance, and selected TR mode, among others. When the user runs off-road using an off-road speed control device at a low speed of, for example, 5 km / h, and the user requests a decrease in the cruise setting speed when the vehicle climbs a steep slope, the tightness of the gradient that the vehicle moves uphill If the system does not take into account such drag / load inducing factors, there is a risk that the torque for maintaining running will be insufficient. Thus, the off-road speed control system can predict that the car may reverse the slope because the torque is reduced more as the slope becomes steep due to a speed reduction request. This is because the vehicle speed decrease due to a slight decrease in the wheel supply torque during climbing is much greater than that when the vehicle is traveling on flat ground. Thus, the torque can be accurately controlled to achieve the desired set speed regardless of the slope or terrain the vehicle travels. This ensures that the responsiveness of the vehicle will be as straightforward and as expected by the driver who may be inexperienced in off-road driving.

When a car user stops or nearly stops on a steep slope while driving in off-road speed control mode, the off-road control system will brake the car while requesting additional support from the hill stop assistance system. Multiply and balance the effect to the appropriate level of engine torque. The hill stop support system is designed to release the brake only when the vehicle is able to obtain enough torque from the powertrain to prevent the car from moving on the hill, in other words, to prevent the car from going backward on the hill. It is an automatic braking function with
In some embodiments, the off-road control system controls the selection of appropriate gears and gear ratios to avoid engine stall and maintain proper progression during off-road driving at low vehicle speeds or otherwise Can affect the choice of

In one embodiment, the off-road control system of the present invention controls the operation of a downhill control (HDC) system that automatically brakes the vehicle when the vehicle goes down a steep slope in an off-road speed selection mode or otherwise. Can affect operation. In this case, the system ensures that the vehicle engine continues to run, but vehicle speed acceleration to the desired set speed cannot be tolerated.
In some embodiments, the vehicle may be operated in an off-road speed control mode when moving forward or reverse.

  The off-road speed control system actively monitors the input from the traction or stability control system to determine if the car is still driving off-road and at the time of traction limitation due to one or more slip events. In order to cope with the increase in the vehicle speed to the set vehicle speed and maintain the travel and momentum of the vehicle in slippery conditions, the operation of the speed control is maintained rather than canceled. If the speed controller is canceled suddenly and automatically in response to a slip event, as in the case of a conventional speed control system, for example, when the traction control system is activated, it is caused by a sudden change in vehicle speed due to the speed controller canceling. The car is probably completely disconnected from the traction or stuck.

  In the following, examples of the present invention will be described with reference to the accompanying drawings only. FIG. 8 shows conditions for dealing with the gradient at two different positions A and B of the vehicle 100 according to the embodiment of FIG. The slope of the position B relative to the car 100 is greater than that at position A.

When the user requests a set speed reduction from the first speed to the second speed at position A, the LSP control system 12 causes the power train 129 to reduce the amount of additional torque applied to the wheels of the car 100 at the first speed, and thus the vehicle. It has a configuration that reduces the speed of 100 to match the newly set speed. The first speed is slower than that when the road surface is flat with respect to the predetermined road surface type. This is to accelerate the vehicle descending due to the deceleration force due to gravity acting on the vehicle 100, that is, in the direction opposite to the traveling direction.
The LSP control system 12 reduces the powertrain torque and optionally applies a braking system in an attempt to keep the vehicle in a reduced state within a predetermined corridor. In some embodiments, the accelerated corridor is of +/− (0.1 g to 0.2 g).

As the car 100 advances and reaches position B, the gradient becomes tighter. When the user requests a decrease from the first speed to the second speed in the same manner at the position B, the LSP control system 12 causes the power train 129 to reduce the wheel added torque amount of the vehicle 100 at the second speed slower than the first speed. Thus, the speed of the vehicle 100 is adapted to the newly set speed. Decreasing the powertrain torque at a slow speed is because the deceleration force acting on the vehicle 100 is relatively large compared to that at the position A so as to accelerate the downhill of the vehicle, and the vehicle speed is relatively quick to reduce the powertrain torque. This is to respond. The LSP control system 12 controls the power train torque (and the brake system torque) so that the reduction of the vehicle can be maintained within a predetermined corridor range of +/− (0.1 g to 0.2 g) in the present embodiment.
9 (a) and 9 (b) are schematic diagrams of specific parameter values for a vehicle shown as a function of time in an example scenario illustrating the operating mode of the LSP control system 12. FIG.

FIG. 9 (a) shows a plot of vehicle speed (v) as a function of time during climbing up a relatively steep slope of the vehicle 100, for example at position B in FIG. At time t = 0, the vehicle 100 moves at a speed v2. At time t = 0, the user moves the brake pedal 163 in the range d1 to d2 (FIG. 7) so as to decrease the set vehicle speed vset in the time length t = 0 to t = t1 (FIG. 9B). Depress and hold. At time t1, the driver releases the brake pedal 163. The LSP control system 12 controls the powertrain torque in response to the decrease in vset, and if necessary, controls the braking torque to decrease the vehicle speed v to the newly set vehicle speed vset. Thus, as shown in FIG. 9A, the speed v is considerably reduced as vset is reduced. The LSP control system 12 controls the powertrain 129 and the brake system to achieve a reduced speed within a predetermined acceleration corridor. In this embodiment, the corridor corresponds to a range +/− (0.1 g to 0.2 g).
The LSP control system 12 is kept active throughout this time period, and the status flag F of the LSP control system is set to F = 1 as shown in FIG. 9B.
FIGS. 9C and 9D schematically show the parameter values of the car shown in FIGS. 9A and 9B in another example scenario.

  FIG. 9 (c) shows a plot of vehicle speed (v) as a function of time during a similarly steep slope downhill. At time t = 0, the car moves at speed v2. At time t = 0, the user depresses the movement amount of the brake pedal in the range of d1 to d2 (FIGS. 7 and 9D) so as to decrease the set vehicle speed vset in the time length of t = 0 to t = t1. Hold. When the set speed reaches the minimum set speed vsetmin at time t1, the driver releases the brake pedal 163. vsetmin corresponds to the allowable minimum set vehicle speed. In some embodiments, the allowable minimum set speed may be about 1 km / h, 2 km / h, 5 km / h, or any other suitable value.

  The LSP control system 12 controls the powertrain torque and, if necessary, the braking torque so as to reduce the vehicle speed to the newly set speed vsetmin in response to the decrease in vset. The LSP control system 12 controls the powertrain 129 and the brake system to achieve a reduction rate within a predetermined acceleration corridor that is +/− (0.1 g to 0.2 g).

  In the illustrated embodiment, the LSP control system 12 determines that it is not necessary to apply a brake system in order to reduce the vehicle speed v to a predetermined corridor speed. However, in the illustrated embodiment, the vehicle speed v decreases to less than the newly set speed vsetmin based on the tightness of the gradient (undershoot condition). Even if the speed drops below vsetmin, the LSP control system 12 controls the speed to return to vsetmin, so the vehicle continues to travel at the newly set vehicle speed vsetmin. As shown in FIG. 9D, the status flag F of the LSP control system remains F = 1 throughout the set speed reduction operation. In other words, the LSP control system does not automatically cancel the LSP control for traveling of the vehicle even when the vehicle speed v falls below vsetmin.

  In one scenario, the LSP control system 12 may determine that the rate of decrease in the speed v is such that the torque required for the car to continue to climb is ultimately insufficient. If so, the LSP control system 12 is operable to prevent reverse travel by applying the vehicle's basic braking system to keep the vehicle stationary. That is, the braking torque is automatically applied. The LSP control system 12 can then control the powertrain 129 to generate sufficient torque to accelerate the vehicle 100 from the rest state to the new set speed vset.

The LSP control system 12 is not always required to keep the car stationary to prevent the car 100 from going backwards. However, in certain embodiments, the LSP control system 12 may be operable to perform this function.
9 (e) and 9 (f) schematically show the parameter values of the vehicle shown in FIGS. 9 (a) -9 (d) in yet another example scenario, further illustrating the operation of the LSP control system 12. FIG. It is.

This scenario is different from the scenario shown in FIG. 9C except that the user releases the brake pedal 163 only after the set speed vset has dropped below the minimum speed vsetmin, such as when the vehicle speed drops to zero in the illustrated example. ) And 9 (d).
FIG. 9 (e) shows a plot of vehicle speed (v) as a function of time during a relatively steep climb similar to scenario B of FIG. At time t = 0, the car travels at speed v2. At time t = 0, the user sets the brake pedal to d1 to d2 (FIGS. 7 and 9) corresponding to a relatively light pressure so that the set vehicle speed vset is decreased from v2 to vsetmin in the time length of t = 0 to t = t1. Depress and hold within the range of f)). When the set speed reaches vsetmin at time t1, the driver maintains a light pressure on the brake pedal 163. In this example, the amount of pressure is relatively light, but is sufficient for the brake system to apply the brake system so that braking torque is applied to the wheels. When the vehicle speed v decreases to zero or a predetermined value equal to or lower than vsetmin, the LSP control system 12 recognizes that the user wishes to invalidate the vehicle control by the LSP control system 12, and controls the vehicle at time t2. Cancel or interrupt. Therefore, the status flag F of the LSP control system changes from F = 1 to F = 0.

  At time t3, the user releases the brake pedal 163. If necessary, a hill stop assist system or others may keep the brake system active to prevent such movement when the car is likely to reverse. At time t4, the user presses the “resume” button 171 to select the operation of the LSP control system 12. Alternatively, the LSP control system 12 may resume vehicle speed control when the user removes his foot from the brake pedal and presses the “+” button. In response to pressing this button, the LSP control system 12 controls the vehicle 100 to accelerate from the rest state to the set speed vsetmin, and in other embodiments the LSP control system 12 stores the memory previously used by the user. User selection of retained user-defined set speeds may be allowed. The LSP control system 12 recontrols the acceleration to reduce it within a predetermined acceleration corridor if possible.

  Embodiments of the present invention can significantly reduce the amount of user work during manual operation, avoiding situations where the vehicle may struggle to move forward or reverse due to a lack of torque supplied to the wheels by the powertrain 129. This has the benefit of minimizing car wear and tear.

4). A-318 Automatic Handling of Obstacles By using a speed control system at low speeds during off-road driving, users can be provided with significant benefits due to reduced vehicle user workload and increased vehicle clearance. . However, if a user tries to deal with off-road obstacles such as rocky land using a conventional cruise control system, the vehicle speed becomes too high under the maximum torque situation required to deal with those obstacles (typically The minimum set speed of the cruise control system is about 50 km / h) or the car engine can be stalled.

  Of particular importance is the fact that cars tend to overrun after riding on rocks. This creates the need for an obstacle to apply a large amount of torque to drive the vehicle over the obstacle and immediately apply a light brake to counteract the engine overrun after the end of the torque request. Is the case. Such precise control of vehicle powertrains and brakes is not possible with currently available cruise control systems.

According to one aspect of the present invention, a speed control system that operates in off-highway conditions, wherein the system maintains a predetermined set speed on the road for one or more wheels of the vehicle. And the system automatically adds braking torque to one or more wheels of the vehicle in response to determining that the vehicle has climbed an obstacle, thus overpowering the train. A speed control system is provided that is operable to cancel a run and substantially maintain a set speed when the vehicle handles an obstacle.
The braking torque may be applied by one or more means selected from among a braking system, an electric machine, a gear shift or any other suitable means, among others.

Embodiments of the present invention are beneficial in that the vehicle's clearance can be maintained without causing an excessive speed change in the vehicle body that can cause the occupant to feel a strong sway (hereinafter referred to as “learning”) when handling an obstacle.
A vehicle obstacle ride is received by a system that can display the vehicle's attitude, for example, received via a controller area network (CAN) or other suitable data bus, direct sensor input or any other suitable means. Can be determined in response to the signal to be. Additionally or alternatively, the ride can be estimated when a decrease in the required torque is detected following a sudden increase in the required torque required to maintain progress.

  Optionally, the system applies braking torque to one or more wheels when the vehicle detects that the vehicle is riding on at least a portion of the obstacle before overcoming the obstacle. It can be actuated. The system may be further operable to increase or decrease the amount of braking torque applied based on the determination that the vehicle is on board so that the set speed is substantially maintained. This feature has the benefit of further increasing the clearance of the vehicle in certain situations because the powertrain acts against the damping force added by the deceleration force to reduce fluctuations in vehicle speed when dealing with obstacles.

  The system operates to detect the ride on one or more wheels of the car with reference to, for example, the car attitude, car attitude change, car suspension movement (stretching) and other suitable parameters. It can be free.

Certain embodiments of the present invention provide information regarding vehicle terrain, as well as vehicle attitude, wheel movement, wheel speed, gear selection, tire friction, roll resistance, and TR (terrain response) mode. Provide a load speed control system.
In certain embodiments, when a user uses off-road speed control to travel across an obstacle such as a walking hole or step, the off-road speed control system provides sufficient torque to overcome the obstacle, and When a decrease in required torque (to maintain a set speed) is detected as the vehicle rides on an obstacle, a braking system that can provide the appropriate restraining force to the vehicle's braking system can be acted upon (for example). The system applies a deceleration force that counteracts the powertrain overrun, thus preventing the vehicle from exceeding the set speed without realizing it, and maintaining clearance and control.

  The responsiveness of the applied torque change rate to the wheel at the braking torque applied by the vehicle brake system (for example) depends on the accelerator pedal or other acceleration input signal (eg, signal from the speed control system) in the internal combustion engine (ICE). It is much higher than that of the powertrain because of its slow response to changes.

  That is, due to the physical characteristics of ICE, the torque output tends to be delayed with respect to the torque request. Specifically, when the high torque demand becomes the low torque demand, the rotational momentum of the engine keeps the torque output at an unnatural height until the engine slows down. Unless the driving force is separated from the wheels by a clutch or similar means, the response delay of the engine can appear as an overrun when overcoming an obstacle in the vehicle, i.e., the vehicle speed can exceed a desired value. This can be perceived as a latching when overcoming an obstacle in the car, causing the car to move too quickly in the direction of the next obstacle and / or causing the rear wheel to crash into the obstacle. These features are eliminated or at least mitigated by an offload speed control system according to an embodiment of the present invention.

  Embodiments of the present invention significantly reduce the amount of user work in manual operation and minimize vehicle wear and tear by avoiding conditions that can cause the vehicle to contact an obstacle at an unnecessarily high speed. The system of the present invention actively monitors the torque demands required to overcome obstacles and manages known control delays by actively using mechanical restraints or damping forces to mitigate overrun after overcoming. Thus, the object is to greatly increase the clearance during off-road operation. As noted above, the damping force can be added by a car braking system, an electrical machine, a gear shift, or any other suitable means.

  As previously mentioned, the off-road speed control system can be provided with information not only on vehicle attitude but also on wheel speed, gear selection, tire friction, roll resistance, wheel movement and TR mode. Thus, when a user moves off-road at a low speed, for example, 5 km / h using off-road speed control, if the car moves on an obstacle such as a step or a walking hall, the off-road speed control system The point of almost overcoming the object can be determined from the required torque change rate, and an appropriate braking torque can be generated (for example) by the brake system to overcome the engine overrun. In this way, the off-road speed control system predicts that the vehicle can be subject to forward learning due to engine overrun caused by a reduction in required torque, thereby countering engine overrun before the vehicle clearance is adversely affected. Measures can be taken.

  An off-road speed control system according to an embodiment of the present invention temporarily places a vehicle in an extreme state in a stationary state (or a substantially stationary state) in order to cope with a terrain such as a rocky place with many obstacles that the vehicle needs to get over. obtain. In those events, the braking torque can be added in response to a ride-over event at any wheel position where an overrun situation would otherwise occur.

  In some embodiments, the off-road speed control system may be configured to ensure that the vehicle is traveling off-road at a low speed with appropriate gear to avoid engine stalls, and that proper progression is maintained. , Can be actuated to control or otherwise influence the “high / low” ratio selection.

  In certain embodiments, the off-road speed control system may be operable to control or otherwise affect vehicle speed to provide time to adjust one or more system configurations. For example, to allow time to change ground clearance, tire pressure, or any other suitable parameter to ensure that the vehicle will travel under the proper configuration to overcome current terrain. Thus, when the vehicle encounters relatively rough terrain, the speed control system may stop or slow down the vehicle to allow for minimum ground height adjustment and / or tire pressure adjustment. In some embodiments, the speed control system may decelerate rather than stop the vehicle so as to reduce the risk of the vehicle losing traction and getting stuck.

  Embodiments of the present invention will be described below with reference to the accompanying drawings only. FIG. 10 shows the amount of torque generated by the powertrain 129 (plot P) and the amount of torque generated by the brake system (plot B) of the vehicle 100 according to the embodiment of the present invention when the vehicle 100 handles an obstacle such as a rock or a step. ).

  At time t <t1, the vehicle is moving on relatively flat terrain at the powertrain generated torque P1. At time t = t1, the car 100 encounters an obstacle. When the LSP control system 12 detects a decrease in the vehicle speed due to the high movement resistance indicated by the obstacle, the LSP control system 12 automatically requests an output increase from the power train 129, and thus maintains the set vehicle speed. In some embodiments, the LSP control system temporarily reduces the maximum allowable set speed upon detecting an obstacle. This vehicle speed may be less than the driver's set speed in certain scenarios.

  When the LSP control system 12 determines that the increase in the powertrain required torque P coincides with the obstacle climbing slope at time t2, the priming of the vehicle brake system is started. This is to prepare the brake system to operate relatively quickly if overcoming is subsequently detected. At time t3, the LSP control system 12 requests that the brake system be operated relatively weakly to give some resistance to the car and reduce the amount of acceleration of the car body when the car starts over the obstacle and descends beyond. . When an increase in the vehicle speed corresponding to overcoming is detected at time t = t4, the LSP control system 12 immediately requests a decrease in the amount of torque P generated by the power train 129. The LSP control system 12 also requests a brake system activation to increase the braking torque B amount, and decreases the speed increase amount of the vehicle 100 due to the powertrain response delay after the powertrain torque P decrease request.

If the vehicle dodges or copes with an obstacle at time t5, the LSP control system 12 requests that the braking torque B be effectively reduced to zero, and the powertrain torque P is sufficient to keep the vehicle speed at a typical set speed. The value drops to the correct value.
Embodiments of the present invention control or otherwise operate the downhill control (HDC) system described above to work with the HDC to optimize vehicle clearance even when dealing with obstacles during downhill. Otherwise it can be affected. Embodiments of the present invention may also be operable to precharge the brake system upon a relatively sudden torque increase request. It may be required to reduce the powertrain torque and optionally add braking torque after a sudden increase in torque. The relatively rapid application of braking torque is beneficial in maintaining the clearance of the vehicle, especially when overcoming obstacles.

5. A-319 Active variable gain control based on torque demand change The use of speed control at low speed during off-road driving may provide the user with significant benefits in terms of user workload reduction and vehicle clearance. . However, when a user tries to deal with obstacles such as off-road steps using conventional cruise control, the maximum vehicle speed is too high or the car engine stalls during the maximum torque situation required by those obstacles. It seems to be. It is particularly important that the internal combustion engine (ICE) tends to overrun when the torque decreases rapidly. The response of the vehicle to the torque increase / decrease request control signal is different due to the inertia of the vehicle and the response difference between the engine and the brake. If the engine torque and the braking torque can be automatically controlled during the off-road operation, an improved method for balancing the engine torque and the braking torque is required to improve the vehicle clearance.

  In some embodiments, the off-road speed control system is provided with at least one selected from information relating to vehicle terrain, vehicle attitude, wheel motion, wheel speed, gear selection, tire friction, roll resistance, and TR mode, among others. Is done.

  Thus, when a user moves over an obstacle such as a walking hole or a step using an off-road speed control system, the off-road speed control system provides sufficient torque to overcome the obstacle, and the powertrain and / or When a signal responding to a torque increase / decrease request from a brake system or the like for applying braking torque to one or more wheels is received, a gain or filter value different from the decrease signal is given to the increase signal. The gain is so varied to compensate for the physical limitations of the system controlled by the signal, and the off-road speed control system balances the control of the braking torque addition means (such as the brake system) and the powertrain to the vehicle. It is configured to maintain a large margin and improve its performance.

  Means for applying braking torque to one or more wheels can be applied to one or more wheels, for example directly via the brake disc of the wheels, or for example to a braking torque as part of the powertrain. It may be operable to add indirectly by adding. Thus, in a hybrid vehicle having an electrical machine that operates as a generator, the off-road speed control system may be operable to apply braking torque to the powertrain via the electrical machine. Other configurations are also useful.

  As noted above, an off-road speed control system according to an embodiment of the present invention includes one of vehicle terrain, vehicle attitude, wheel motion, wheel speed, gear selection, tire friction roll resistance, and TR mode. Information about one or more may be provided. Thus, when a user moves off-road at a relatively low speed, for example, 5 km / h, using an off-road speed control system, when the car moves on an obstacle such as a walking hall or a step, the off-road speed control system The braking system (or other braking torque, or one or more other braking torques) is applied to determine when the vehicle is almost over an obstacle by the required torque change rate and to apply an appropriate restart torque to overcome engine overrun. Means for adding to the wheel). Thus, an off-road speed control system according to an embodiment of the present invention allows the vehicle to move forward relatively quickly due to engine overrun under predictive conditions that reduce the required torque (ie, after the vehicle has overcome an obstacle). It can be determined that the vehicle can accelerate, and countermeasures against engine overruns can be taken before the vehicle's clearance is adversely affected. Thus, the car can interpret the sudden increase in required torque to maintain progress as an indication that there is likely to be a corresponding sudden decrease in required torque. Accordingly, the speed control system applies the brake system so that the powertrain acts against the action of the brake system. After the vehicle gets over, the amount of braking force can be increased to reduce the possibility that the user will feel the body motion as a learning.

  In one embodiment, the off-road speed control system works with the powertrain and braking torque addition means to balance their torque effects on the vehicle and to balance each other with respect to time delay characteristics, particularly with respect to the operating device. May be deliberately requested to

Braking torque may be applied to the one or more wheels to balance the required engine torque if wheel spin at one or more wheels is predicted when the engine torque is applied.
The off-road speed control system controls or otherwise selects the gear and gear ratio to ensure that the vehicle avoids engine stalls and moves slowly off-road with the appropriate gear to maintain a favorable progression. Otherwise it can be affected.

  The off-road speed control system of the present invention can work in conjunction with the downhill control (HDC) system described above to optimize car clearance even when handling downhill obstacles. In some embodiments, the HDC braking request may be configured to override or otherwise override the off-road speed control request when the vehicle's moving slope is greater than or equal to a predetermined value.

  Embodiments of the present invention act to accelerate the vehicle positively or negatively, such as dealing with a slope such as an obstacle, hill or others, or moving on terrain that provides a relatively high drag or roll resistance. It is beneficial in that it can maintain a space when moving on terrain that receives relatively strong forces. Accelerate the car by a predetermined amount when climbing the slope of the car (acceleration in the range of 0.1 to 0.2 g, which is parallel to the direction of movement and is comfortable enough to withstand sustained or repeated events by the car occupant The amount of engine torque required to make the vehicle is much larger than that when the vehicle is moving on a flat surface or when the vehicle is inclined down. Similarly, if a vehicle experiences a relatively high drag or roll resistance while moving on a flat or inclined surface, the powertrain torque value is much greater than that when moving on a road surface with a relatively low drag or roll resistance. Is required.

  According to the embodiment of the present invention, the gain amount to be added to the increase torque request signal is changed in comparison with that in the decrease torque request signal according to the external force value to be added to the vehicle as the acceleration force. Improved car clearance when dealing with different terrain is promoted. The acceleration force may be positive or negative, and the embodiment of the present invention may receive a positive or negative acceleration force. Embodiments of the present invention can maintain vehicle acceleration within a predetermined corridor (e.g., in the range of +/- (0.1 g to 0.2 g)), thereby preserving occupant comfort during acceleration or lowering events. The

  The acceleration force can be received on the slope of the car based on gravity. Alternatively or additionally, the acceleration force can be received based on drag or roll resistance, which results in a negative acceleration (i.e., reduction) of the vehicle while traveling on the road surface at a predetermined speed.

  The off-road speed control system determines that an external force is acting on the car moving on the road surface (for example, due to the effect of gravity when climbing or due to the drag effect when traveling on sandy terrain), In response to a request to add negative torque to one or more wheels (by increasing the speed at which the vehicle is applied to one or more wheels by the powertrain). On the other hand, it may be configured to provide a low gain (thus reducing the rate of increase of braking torque that reduces the vehicle). This is because, under such conditions, the external force acts against the acceleration of the vehicle and opposes the additional torque of the power train, but similarly acts as a braking torque that decelerates the vehicle.

  Conversely, when it is determined that the external force acts to promote the operation of the car on the road surface (for example, due to the influence of gravity during downhill), the off-road speed control system is low for positive wheel torque increase demands. Gives gain (thus reducing the drive torque application speed to one or more wheels by the powertrain) and high for negative torque application requirements to one or more wheels It may be configured to provide gain (thus increasing the rate of increase of braking torque that decelerates the car). This is because the external force acts to promote the acceleration of the vehicle, thereby acting in the same way as the additional torque of the power train, but acting against the braking torque to decelerate the vehicle.

Embodiments of the present invention will be described below with reference to the accompanying drawings only. FIG. 11 is a plot of power train torque P and braking torque B applied by the speed control system according to the embodiment of the present invention. An example of such a system is the LSP control system 12 mounted on the car 100 of the embodiment of FIG. Each plot corresponds to a particular different scenario.

  In one scenario, the driver requests an increase in vehicle speed at time t = t1. When the vehicle 100 is climbing up, a relatively high gain is given to the demand for increasing the powertrain torque compared to that when the vehicle moves on flat ground, and a certain scenario (predetermined slope, terrain type, expected) And the set speed after the change), the powertrain torque is increased by the system 12 according to the trace P1. When the vehicle 100 is accelerated to a new (high) set speed, the powertrain torque P decreases to a value sufficient to maintain the new set speed.

  Trace B1 corresponds to the braking torque B as a function of time when the car 100 is going down the same slope and a set speed reduction is required. The amount of increase in the braking torque B is relatively small compared to when moving on a flat road because the vehicle has already been decelerated due to gravity.

  Trace P2 in FIG. 11 shows the required powertrain torque P as a function of time when the vehicle is descending, and the set speed increase, which is a value similar to that previously described for trace P1 of LSP control system 12. Indicates. A low gain is given to a request for increasing the powertrain torque for accelerating the vehicle 100. At time t2, the amount of powertrain torque is reduced to a value sufficient to maintain operation at the newly set speed. If the slope is tight enough, an increase in powertrain torque cannot be required. Rather, it may be sufficient to reduce the braking torque B to accelerate the car to the new set speed. Thus, the LSP control system 12 can utilize the driving terrain of the vehicle to respond quickly to the user's request while traveling with ease and good fuel economy.

  For comparison, trace B2 corresponds to the braking torque as a function of time when the vehicle 100 is downhill and when a set speed reduction to a value similar to that in the scenario shown in trace B1 described above is required. To do. Since gravity counteracts deceleration, a high gain is applied to the braking request signal to reduce the vehicle speed within a predetermined corridor (in some embodiments, the vehicle 100 is in the range of 0.1 g to 0.2 g). Like slowing down).

Other accelerated corridor values are also useful, and the corridors referred to herein (+/− (0.1 g to 0.2 g)) are not limiting. A faster deceleration corridor may be preferable to an accelerated corridor to increase user satisfaction with quick system responsiveness to user demand.
By adjusting the gain in the manner described above, the behavior of the vehicle can be maintained constant regardless of the moving terrain of the vehicle.

6). A-320 Powertrain adaptive control based on slip events The use of speed control at low speeds during off-road driving provides significant benefits to the user in terms of reducing user workload and increasing vehicle clearance. However, if the user uses speed control to deal with off-road steep slopes and try to increase the climb speed, the powertrain controller can increase the engine torque too rapidly, resulting in loss of traction. If a slip event occurs during a vehicle speed increase request, the full speed control function can be interrupted.

In one embodiment of the present invention, an off-road speed control system is provided that has information regarding not only the terrain on which the vehicle travels, but also vehicle attitude, wheel movement, wheel speed, gear selection, tire friction, and TR mode.
In some embodiments, an off configured to temporarily maintain vehicle speed or temporarily interrupt vehicle acceleration when a slip event is detected upon response of a speed control system to a user's vehicle acceleration request. A load speed control system is provided. In one embodiment, the vehicle speed is held at the speed at the first slip event that the car encounters. In one embodiment, the system is configured to resume the acceleration of the vehicle toward the user selected high set speed only after the slip event has converged.
Thus, the offload speed control system can accept a set speed increase that achieves the set speed only if traction allows.

In some embodiments, the wheel speed is reduced such that wheel slip is limited to a predetermined amount, such as an amount of about 5% to about 20%. Other amounts are also beneficial. The amount may be based on vehicle speed, wheel movement, vehicle attitude, and / or selected TR mode. Other parameters are also useful for addition or substitution.
In one embodiment, if one or more wheels slip after a reduction in vehicle speed, the wheel speed is further reduced so that the amount of wheel slip decreases within the predetermined range described above.

  According to one aspect of the present invention, a speed control system operable under off-highway conditions, wherein the system provides a required torque for maintaining a predetermined set speed on the road to one or more wheels of the vehicle. A speed at which the system is operable to automatically interrupt acceleration when a slip event exceeding a predetermined value is detected when the speed control device accelerates the car to a new set speed, requiring the powertrain to add A control system is provided.

  According to yet another aspect of the invention, a speed control system operable under off-highway conditions, wherein the system provides a required torque for maintaining a predetermined set speed on the road to one or more vehicles. If the system detects that a slip event exceeding a predetermined value is detected when the speed control device accelerates the vehicle to a new set speed, the system detects the vehicle speed and the slip exceeding the predetermined value. A speed control system is provided that is operable to automatically maintain at a detected speed.

  According to yet another aspect of the invention, a speed control system operable under off-highway conditions, wherein the system provides a required torque for maintaining a predetermined set speed on the road to one or more vehicles. If the system detects that a slip event exceeding a predetermined value is detected when the speed controller accelerates the car to a new set speed, the system will cause the wheel speed to exceed the predetermined value. A speed control system is provided that is operable to automatically maintain at a detected speed. This action can be performed until the wheel slip is below a predetermined value, at which point the system can control the acceleration to achieve the new set speed for the car.

  In each aspect described above, the system may be operable to resume acceleration after the slip event has converged. Slip event convergence may be determined with reference to a suitable signal such as a flag that is set when the traction control system (TCS) or stability control system (SCS) is activated. When the TCS or SCS activation is no longer displayed, the off-road speed control system may resume vehicle acceleration. In some embodiments, the off-road speed control system may resume acceleration at one selected from a predetermined length of time and a predetermined distance, among other things, after detecting excessive wheel slip. Other configurations are also useful. Signal flags from other subsystems may also be useful.

  In some embodiments, the off-road speed control system may be operable to interrupt acceleration when the vehicle steps over and maintain the vehicle speed at the same speed as when the steps are encountered until the steps are overcome. In some embodiments, when crosstalk is detected, acceleration may be limited to deal with waves from the front and to improve vehicle controllability.

  In one embodiment, the off-road speed control system handles the slip event (or step) detected on one or more following wheels (or rear wheels if the vehicle moves forward) of the vehicle. It may be different from that in a slip event detected on one or more preceding wheels (or front wheels if the car moves forward).

  In some embodiments, the speed control system may be operable to detect when the car can cross or cross the slope. In one scenario, when a car crosses a slope that increases the left side of the car, the load on the vehicle on one or more wheels on the uphill side, such as the front and rear left wheels, can be lower than that on the front and rear right wheels. . In this embodiment, when the left wheel slips and the tilt or other sensor output detects the climb on the left side of the vehicle, the speed control system causes the vehicle speed to be less than a predetermined value (the user's Attempts to decelerate temporarily based on the set speed value.

  In some embodiments, the off-road speed control system confirms a slip event (or step appearance) at a time proportional to the vehicle speed and the wheelbase of the vehicle that one or more of the preceding wheels are probably slipping. It can be actuated to predict based on that. The speed control system may be operable to cope with slipping or stepping over one or more following wheels by reducing the acceleration effect of the vehicle due to the following wheel slip. Vehicle acceleration can be reduced when slippage occurs when both front and rear wheels on the same side pass through a specific slippery road patch. Vehicle acceleration in response to user requests may be reduced until grip is restored.

  Embodiments of the present invention are beneficial in that the impact of wheel slip during acceleration can be reduced when the speed control system attempts to accelerate the vehicle. In some embodiments, vehicle clearance can be substantially improved. This is because, at least in part, the amount of slip of one or more preceding wheels (following wheels in some embodiments) interrupts acceleration when detecting slip of one or more preceding wheels. Because it can be reduced. Furthermore, in some embodiments, the amount of damage received from off-road surfaces based on one or more slip events may be reduced.

In some embodiments, the off-road speed control system may select gears and / or gear ratios to ensure that the off-road travels at low speed with optimal gear to avoid engine stall and maintain good progress. Can be actuated to control or otherwise affect.
In some embodiments, the off-road speed control system is operable to work with a downhill control (HDC) / slope stop assist system to optimize vehicle clearance even when dealing with steep obstacles. It can be. The braking request of the downhill control (HDC) / slope stop support system is a request from the off-road speed control system when the gradient of the moving vehicle is larger than the predetermination value and / or the speed is equal to or less than the predetermination threshold Disable or otherwise take precedence.

In some embodiments, when accelerating from a current cruise speed to a modified set speed, the acceleration employed by the speed control system may be affected by a preset performance characteristic indicated by the terrain response depending on the terrain mode.
In some embodiments, the vehicle can be operated in an off-road speed control mode in either a forward or reverse direction.
Embodiments of the present invention will be described with reference to the accompanying drawings only. FIG. 12 is a plot illustrating vehicle speed v, vehicle set speed vset, and traction control system (TCS) flag state T as a function of time, according to one embodiment of the present invention moving in changing terrain.

At time t = 0, the vehicle 100 is moving at the speed v1 under the control of the LSP control system 12 with the set speed vset = v1. At time t = 1, the user of the car 100 increases the vset value to vset = v3. In response, LSP control system 12 accelerates vehicle 100 from speed v1 to v3.
In the illustrated example, at time t = t2, the TCS system intervenes in the vehicle travel control to control the traction of the vehicle 100 to deal with excessive slip of one or more wheels 111-115. The value of the TCS system flag state T changes from T = 0 to T = 1 when the TCS system starts intervention. The LSP control system 12 interrupts further acceleration of the vehicle 100 in response to the value of the TCS system flag state T changing from T = 0 to T = 1. The LSP control system 12 maintains the vehicle speed at the vehicle moving speed (v2) immediately before the start of the TCS system intervention. If excessive slip still occurs, the LSP control system 12 can reduce the wheel speed to a speed below the vehicle movement speed just prior to the start of the TCS system intervention, ie below v2. The TCS system can be activated while the vehicle is accelerating against a number of different reasons, such as slippery flats or slippery sloped terrain.

In one embodiment, the LSP control system 12 maintains the vehicle speed at v = v2 until the TCS flag state returns to T = 0. Next, the LSP control system 12 tries to increase the vehicle speed to the newly set speed v3. In some embodiments, the LSP control system 12 may wait for a predetermined length of time after T is set to 0 (the time length may be a predetermined length of time in certain embodiments, or the vehicle speed, TCS flag status may be A time length set to T = 1 and / or a time length selected according to one or more of the parameters, such as one or more parameters of other additional or changing parameters ). In this embodiment, the LSP control system 12 retries to increase the vehicle speed after waiting for a predetermined time length (for example, 1 second). Thus, the LSP control system 12 waits for 1 second when the TCS flag state is reset to T = 0 at time t = T3, and then increases the additional torque on the wheels at time t = t4 to speed the vehicle v = v3. Accelerate to. At time t = t5, the vehicle 100 reaches the newly set speed vset = v3.
Trace v ′ in FIG. 12 shows the predicted vehicle speed as a function of time when T = T1 is not set during the length of time that the TCS flag state T accelerates from v1 to v3.

  Embodiments of the present invention have the benefit that the vehicle's clearance during acceleration in off-road speed control mode can be increased. In some embodiments, the effects of tire corrosion on off-road routes may be reduced, improving both tire wear and fuel consumption. Vehicle clearance can be increased by using an LSP control system to handle available grip levels and engine overrevs. In addition, the LSP control system 12 is not canceled during a traction control or slip event. Canceling off-road operation can lead to instability and increased workload.

7). A-321 Vehicle response to repeated detection of front-to-back slip events:
Using speed control when driving off-road at low speeds will provide users with significant benefits in terms of reducing user workload and improving vehicle clearance. However, if the user attempts to use speed control off-road, the powertrain / traction controller may attempt to intervene when a slip event is detected. The impact of this intervention is doubled when a slip event is first detected on the preceding wheel and then on the rear wheel following the preceding wheel. The intervention may interrupt full speed control functionality.

  According to one aspect of the present invention, there is a speed control system that includes, among other things, information relating to vehicle terrain, vehicle attitude, wheel motion, wheel speed, gear selection, tire friction, roll resistance, and selected TR mode. A speed control system is provided in which at least one selected from is provided. Such information is not provided in vehicles that do not have one or more terrain response modes.

  An off-road speed control system according to an embodiment in one aspect of the present invention detects the occurrence pattern of slip events and / or step encounter events, and optionally the vehicle speed and, optionally, the steerable wheel angle, and / or It has a configuration for monitoring the handle angle. The system may be operable to predict that a slip event or step encounter event detected on a preceding wheel will subsequently be detected on a following wheel that follows the path of the preceding wheel.

  As previously described, an off-road speed control system according to an embodiment of the present invention may be operable to accelerate the vehicle to a new set speed when the set speed is increased while the car is traveling on terrain. If a slip of one or more wheels is detected during the acceleration of the vehicle, or optionally a step encounter is detected, the speed control system temporarily limits further acceleration of the vehicle speed. May be actuated as such. If a slip event or step encounter event is detected on the preceding wheel (or front wheel if the car is moving forward), the speed control system will detect if a slip or step encounter event is subsequently detected on the following wheel, and However, if it is determined that the following wheel has passed over a similar terrain similar to that in which the preceding wheel has already slipped, it may be operable not to take the same action or to operate for the same length of time. For this purpose, in one embodiment, the system delays acceleration restart after detecting a slip event on the preceding wheel, possibly based on time proportional to vehicle speed and wheelbase, after the preceding wheel slip falls below a predetermined threshold. . The predetermined threshold may range from about 5% to about 20%. Other configurations are also useful.

  In some embodiments, the off-road speed control system may be configured to temporarily suspend vehicle speed or vehicle acceleration when a slip, step (or curb) encounter event is detected. The vehicle speed can be substantially maintained at the time the vehicle first encounters a slip event or step encounter event, or can be reduced if the leading wheel continues to slip above a defined threshold. The system may be operable to maintain speed or interrupt acceleration while the speed control system is active, regardless of user requirements. However, in some embodiments, the user can disable the speed control system and the powertrain torque can be forcibly increased by canceling the speed control system operation or by the user accelerating or operating the controller by a suitable amount.

In some embodiments, acceleration to the high set speed selected by the user is resumed only when the slip event ends or the step (or curb) is overcome. Thus, the speed control system will accept an increase to the set speed when the offload speed control system is active, but will only attempt to achieve the set speed if traction allows.
In one embodiment of the off-road speed control system, a slip event (or step encounter) is first detected on one or more preceding wheels and subsequently detected on one or more corresponding following wheels. The case action is different from that when a slip event or step encounter event is detected on only one or more preceding wheels.

In one embodiment, the controller predicts the terrain path followed by the front and rear wheels and the time delay from the preceding wheel passing a fixed point until the following wheel encounters the same fixed point. A slip event or curb is detected on one or more rear wheels at a time proportional to the vehicle speed and wheelbase by the off-road speed control system based on an existing front wheel slip or curb encounter. If the off-road speed control system is predicted to be likely to occur, the off-road speed control system may respond to this repeated slip or step encounter event with one or more dominant conditions, eg, slip amount or step tightness. Appropriate measures are taken against such problems. For vehicles having one or more terrain-aware modes, the off-road speed control system may take into account the selected terrain settings of the terrain response system. The embodiment of the present invention is such that the acceleration effect of the vehicle is doubled when the preceding wheel and the following wheel on the same side of the vehicle pass through the same low mu (i.e., low friction coefficient vehicle) traveling surface intermittently. Is intended to be able to avoid this. Similarly, in the case of steps in the present invention, in the case of a step, the speed control system accelerates the vehicle to the set speed as quickly and effectively as possible without impairing the clearance of the vehicle, thereby increasing the comfort of the vehicle occupant. It is intended to be able to maintain.
In some embodiments, the off-road speed control system may avoid gear stalls and ensure that the off-road travels at low speed with optimal gear to maintain good progress and gear and / or “high / It may be operable to control or otherwise affect the “low” gear ratio selection (if appropriate).

  Certain embodiments of the present invention may be able to work with an HDC (RTM) / hill stop assistance system to optimize car clearance even when dealing with obstacles on tight slopes. In some embodiments, the braking command of the HDC (RTM) / hill stop assistance system disables the off-road speed control system when the vehicle is traveling at a slope greater than the pre-determined value and / or the speed is less than or equal to the pre-determined threshold. Or configured to take precedence over it.

The acceleration from the current speed to the changed set speed may be affected by the pre-set performance characteristics indicated by the terrain response system depending on the terrain mode.
The embodiment of the present invention can greatly reduce the tire corrosion effect on the off-road route, and can improve tire wear and fuel consumption. Embodiments of the present invention may further improve vehicle clearance by applying available grip levels and resisting engine overrevs.

  As previously mentioned, in some embodiments, one or more preceding wheels have slip events or curb encounters, and one or more following wheels are within a predetermined distance of the leading wheel path. Once determined to pass, the system may control the operation of the vehicle in a manner that reduces the impact on the speed of travel of the vehicle and / or occupant comfort in terrain that causes a slip or step encounter event. The reduction of the effect on speed of travel and / or occupant comfort may be related to the effect that the following wheel would have experienced if the speed control system did not take the expected action. In some embodiments, the off-road speed control system may redistribute powertrain torque between one or more wheels in response to detection of a leading wheel slip or step encounter event, thus It is possible to reduce the amount of torque applied to the follower wheel that passes within a predetermined distance of the position where the slip or step is encountered. In one configuration, the predetermined distance is short enough (optionally substantially) that the path of the following wheel must pass through the path of the preceding wheel to produce a torque redistribution response by the off-road speed control system. Equal to 0). Torque redistribution may be performed by one or more powertrain clutches, optionally in a rear, center, or front differential configuration.

  In some embodiments, the off-road speed control system is configured to reduce the amount of torque applied to the following wheel to a value that reduces the slip of the preceding wheel and / or to a predetermined value (for example, 20% or less). Can have. The amount of additional torque can be reduced when the follower wheel enters a predetermined terrain distance that causes the preceding wheel to slip or encounter a step in certain embodiments, but other configurations are also beneficial.

  In some embodiments, the off-road speed control system may reduce the amount of torque applied to the following wheel to substantially zero. In some embodiments, the speed control system may be operable to increase the amount of additional torque on the preceding wheel when the following wheel is substantially within a predetermined distance of the preceding wheel. In one embodiment, the torque distribution is varied for one selected from among a time length or a distance corresponding to the distance traveled by the preceding wheel causing the slip. Other configurations are also useful.

  Under conditions where obtaining as much traction as possible is important, the amount of torque added to the preceding wheel is temporarily increased. In front-type embodiments with a front-mounted engine, the vehicle weight ratio on the front wheels of the car is typically due to the vehicle load due to the presence of the engine and transmission in front of the car, typically Can be much higher than that of the car rear wheel. Therefore, under certain conditions, the traction obtained from the front wheels can be much larger.

In certain embodiments, braking intervention may be applied if it is predicted that the following wheel may encounter a slip based on the detection of a preceding wheel slip encounter. In some embodiments, braking force acting against powertrain torque is added to one or more following wheels to reduce the risk of wheel flare when encountering a low coefficient of friction area. obtain.
In some embodiments, braking intervention may be applied once a step slip encounter on a preceding wheel is predicted based on detection of a step slip encounter on the preceding wheel. In some embodiments, when dealing with terrain steps, acts against powertrain torque to reduce the risk of occupants experiencing changes in the speed of the vehicle that the occupants feel, for example, as rocking, rock formation, or learning due to the appearance of steps A braking force can be applied to one or more following wheels.

  Embodiments of the present invention will be described below with reference to the accompanying drawings only. The operation of the vehicle 100 according to the embodiment of the present invention will be described with reference to FIG. The vehicle 100 is operated in a four-wheel drive mode in which a powertrain torque is added to each of the four wheels 111, 112, 114, 115 when the vehicle 100 is traveling. FIG. 13 is a plot showing the vehicle speed v, the LSP control system set speed (set by the user) vset, and the traction control system (TCS) state flag T as a function of time t when the car 100 climbs a slope with a predetermined slope. It is. The slope has intermittent parts (wet grass, mud, etc.) with a relatively low road surface friction coefficient. At time t = 0, the car climbs up at the user set speed vset = v = v1 under the control of the LSP control system 12. At time t = t1, the user depresses and holds the accelerator pedal 161 of the vehicle 100 by an amount within the range of d = d1-d2 (FIG. 7) to increase the set speed from vset = v1 to vset = v3. The LSP control system 12 accelerates the vehicle 100 to a speed v = v3 and ensures that the acceleration is maintained within a predetermined corridor of, for example, +0.1 g to 0.2 g.

  At time t = t2, if the vehicle 100 encounters a relatively low friction count region and causes excessive slip, the TCS flag state is set to T = 1. In response to this, the LSP control system 12 interrupts the subsequent acceleration and tries to maintain the vehicle speed at v = v2. Thereby, the wheel speed is reduced or maintained at the vehicle speed immediately before the occurrence of the slip. In some embodiments, in addition, a braking system is provided that acts against one or more slipped wheels against the powertrain torque, thus providing a braking torque that can act against the powertrain torque. Provided to reduce the risk of destabilization.

  At time T = T3, the TCS flag state is set to T = 0, which indicates that there is no longer excessive wheel slip. Then, the LSP control system 12 resumes the response to the user-defined set speed request and tries to accelerate the vehicle 100 to achieve the user set speed v = v3.

  The LSP control system 12 calculates the path of the following wheel with respect to the preceding wheel of the vehicle 100 according to the vehicle traveling from the position where the TCS flag state is set to T = 1. The LSP control system 12 is likely to pass one or more following wheels within a first predetermined distance position where the TCS flag state is set to T = 1 due to the movement of one or more preceding wheels. If it is determined, the path of one or more following wheels on the road is calculated. This determination is performed in consideration of the position of the steerable wheels 111 and 112 of the vehicle 100 and / or the angular position of the handle 171.

  When one or more following wheels enter a first predetermined distance with the TCS flag state set to T = 1 due to the movement of one or more preceding wheels, the LSP control system 12 Add braking torque to one or more following wheels against the powertrain torque applied to these following wheels and / or disconnect one or more drive torques It is configured to move to another wheel that has been determined to be less susceptible to slip. This reduces the risk that these following wheels will become unstable if they encounter a road surface with a relatively low road surface friction coefficient similar to that of the preceding wheel. In some embodiments, the LSP control system 12 further increases the amount of additional torque applied to the preceding wheels of the vehicle 100 to compensate for the decrease in net torque applied to the following wheels when braking torque is applied to the following wheels. Let

In one embodiment, the LSP control system 12 determines that the following wheel path for the preceding wheel path is moved when the following wheel moves from a position where the TCS flag state T is set to T = 1 at a moving distance proportional to the wheelbase length of the vehicle 100. Without calculation, braking torque or powertrain torque is added between the wheels. In some embodiments, the distance traveled may be slightly shorter than the wheelbase length. This can give rise to drive train response time, which has a beneficial and stable effect on vehicle clearance.
In one embodiment, the first predetermined distance is about 1 m, but other values are useful.

  In some embodiments, the LSP control system 12 can reduce or reduce the amount of applied torque to one or more following wheels in addition to or instead of adding braking torque to the following wheels. The powertrain torque can be redistributed between the following wheel and the preceding wheel so that the amount of torque added to the preceding wheel is increased. This has the benefit of reducing the risk of TCS system intervention due to excessive slip on the following wheels when passing through the low road coefficient of friction region. In other words, the LSP control system 12 can increase the amount of additional torque applied to the preceding wheel in order to compensate for the decrease in net additional torque applied to the following wheel. This action can be useful in reducing the effect on the traveling speed of the vehicle across the terrain when traveling on the low friction coefficient road surface area.

In some embodiments, the speed control system 12 may separately calculate the left following wheel path for the left leading wheel path and the right following wheel path for the right leading wheel path. Alternatively, the system can calculate the path of each wheel for a single preceding wheel based on the direction of travel of the vehicle.
In some embodiments, the speed system may handle slip and improve vehicle clearance by distributing more torque to one or more wheels on a harder, more compacted high grip surface. It can be actuated.

  In one example operation of a car, the car can move from a compaction road surface to a relatively soft road surface and then move back to the compaction road surface. As the vehicle moves on a soft road surface, the system may be configured to distribute more torque to one or more following wheels to push the vehicle on the soft road surface. The system may be operable to increase the torque distribution to the preceding wheels in order to pull the car on a firm road surface after passing through a soft road surface. The system monitors the vehicle's response to one or more external forces and distributes torque between the wheels to increase vehicle clearance.

In some embodiments, the speed control system may selectively increase the amount of additional torque to compensate for the relatively large drag for one or more wheels that are subjected to a relatively high drag.
In some embodiments, the speed control system is operable to determine a torque increase for either a wheel that is subject to high or low drag, after determining which is optimal in optimizing vehicle clearance. possible.

  Embodiments of the present invention provide one or more follow-ups when encountering a road area known to be a low road friction coefficient based on a previously detected slip event for one or more wheels. Predicting wheel slip has the benefit of reducing the amount of slip of one or more following wheels with respect to one or more preceding wheels.

8). A-322 Car control in response to drag changes:
By using a speed control system at low speed when traveling off-road, the user can be provided with significant benefits due to reduced user workload and increased vehicle clearance. However, if the user uses an off-road speed control system, when the drag amount decreases when the powertrain controller attempts to provide a sufficient amount of torque to overcome the high drag, one or more The amount of torque applied to the wheels may exceed that required to maintain dominant installation speed and vehicle clearance. This can cause the occupant to receive a speed change of the vehicle body that the occupant feels as a learning. One example is when a car moves from soft sand to asphalt or concrete road. While traveling on the sand, a relatively large amount of torque is required to overcome the drag on the car and maintain the desired set speed. When the car tires come into contact with the road surface, the drag is greatly reduced. However, the powertrain cannot reduce the amount of torque applied to one or more wheels fast enough to compensate for terrain changes. This is due to the rotational momentum of the engine. As a result, at the moment when the tire grips the road surface, the power train generates torque more than necessary to deal with the new road surface, and instantaneously exceeds the target speed of the vehicle, which adversely affects passenger comfort. This effect can be difficult to control if the terrain constantly changes. Powertrain response delays can be particularly apparent to users in the environment.

  In one embodiment, the off-road speed control system according to the present invention includes, among other things, the terrain on which the vehicle travels, the attitude of the car, wheel movement, wheel speed, wheel rotation, gear selection, tire friction, roll resistance, and selected TR mode. At least one selected from information regarding may be provided. Such information is not provided in vehicles that do not have one or more terrain response modes.

  In some embodiments, the off-road speed control system monitors drag patterns or changes to the vehicle, such as due to soft sand or deep water driving, and may cause perceptible speed overshoots and / or rolls. The vehicle speed is configured to predict a decrease in one or more parameters such as resistance. The overshoot may be due to a temporary excessive supply of powertrain torque. This system can cope with this overshoot by automatically adding an appropriate restraining torque.

  Restraint torque can be applied by applying a braking system to one or more wheels in an electric machine (in some embodiments, for example, can be part of a regenerative braking system), for example, by changing a selected gear of a transmission. It can be provided by changing the powertrain gear ratio or by any other suitable means.

  Compensation for temporary torque overshoot by application of appropriate counter torque can maintain vehicle clearance, avoid speed overshoot, or at least reduce excess. The off-road speed control system can compensate for the temporary torque fluctuations required when driving on terrain where the friction changes (and thus the wheel drag changes) by adding an appropriate counter torque (positive or negative). Thus, the vehicle's clearance can be maintained and speed overshoot or undershoot can be avoided.

  In one embodiment, the off-road speed control system is one that receives a relatively high drag when determining the amount of counter-torque addition to the powertrain to reduce the risk of the occupant being subject to vehicle body speed changes as felt by the occupant. Or it may be configured to take into account the drag on the car at one or more wheels. The net required counter torque amount is determined from the counter torque amount in the powertrain, the drag acting on the vehicle or other braking torque, for example, the roll resistance of one or more wheels, or the other acting on the vehicle, such as water This can correspond to the amount of surplus torque obtained by reducing the drag caused by crossover. In some embodiments, gravity effects on the car due to the gradient may be considered.

  When a car deals with sandy ground, if one or more of the leading wheels of the car encounters a relatively low drag road surface (such as a paved road), one or more The required torque amount to be applied to the preceding wheel can substantially correspond to the surplus power train generation torque amount obtained by subtracting the counter torque amount of the power train based on the drag force of the following wheel in the sand.

One or more leading wheels can act as a pathfinder for one or more following wheels. In some embodiments of the present invention, during forward movement of the vehicle, in some embodiments, in particular, one or more rear wheel burden loads are less than that of one or more front wheels, Since the vehicle occupant is more sensitive to rear wheel motion than front wheel motion, maneuvering comfort can be increased.
In one embodiment, an off-road speed control system is provided that controls vehicle speed to a set speed selected by a user, allowing the user to operate the vehicle at low speed off-road.

  As previously described, in some embodiments the off-road speed control system may be configured to monitor a vehicle drag pattern or change that may occur, for example, due to sand or deep water passage. The system uses these patterns or variation data in combination with vehicle speed knowledge to predict where the drag that is likely to cause perceptible speed overshoot is reduced. Thus, in some embodiments, the off-road speed control system predicts where a temporary oversupply of torque is likely to occur and applies the appropriate restraint torque to the powertrain, optionally via a brake. To compensate for such oversupply. Compensation for temporary torque overshoot by adding appropriate counter torque can maintain the vehicle's clearance and avoid speed overshoot.

  In some embodiments, the off-road speed control system may form part of an all terrain progression control (ATPC) system that optimizes the vehicle configuration by itself or for a predetermined terrain on which the vehicle travels. It may have a configuration that works in combination with a vehicle control system having the configuration. An example of such a system is a terrain response (RTM) system.

  In one embodiment, the off-road speed control system according to one embodiment of the present invention is configured to select a selected TR mode, road roughness, brake temperature, slope, and the user, for example, accelerator pedal depression, off-road speed control set speed. It may be configured to determine the braking torque application time point based on a factor such as a change or a determination as to whether manual intervention has been performed on the progress control device due to a change in the TR mode. Other configurations are also useful.

  In some embodiments, when a user requests an increase in vehicle speed through an off-road speed control system, the system temporarily maintains the vehicle speed or interrupts the acceleration of the vehicle when a torque overshoot is predicted, causing an undesired acceleration. Only in the case where it is believed that it can be offset, it can have a configuration that increases the acceleration of the car to a higher set speed. Thus, the car can accept a set speed increase when the off-road speed control system is active, but on the driving terrain, the car has a defined corridor (ie, a predetermined range, optionally about +/- (Between 0.1 g and 0.2 g), and only when the acceleration of the vehicle that does not cause overshoot due to the detected drag change is allowed, the achievement of the set speed is attempted.

  In some embodiments, the reliability of drag change prediction can be further increased by monitoring the leading wheel and following wheels or the leading wheel drag change point in each tire path with a speed control system. In this way, the controller can assume that when the following wheel is following the preceding wheel path, the drag received at the time when the following wheel is proportional to the vehicle speed and the wheel base is less than the drag received by the preceding wheel. This method shifts the undesired torque to the high drag area of the tire during the window in which torque overshoot is expected (otherwise subjecting the vehicle to acceleration that can be felt as a ratcheting). Can be used. Undesired torque is shifted by one or more clutches and / or differential configurations (which may include one or more clutches), eg, front, center, and / or rear differential configurations. obtain. Other configurations are also useful.

  In some embodiments, the off-road speed control system may allow the vehicle to off-road at a selected transmission gear and / or at a selected high / low ratio appropriate to avoid engine stalls and maintain good progress. The gears and / or the “high / low” ratio selection can be controlled or otherwise actuable to ensure that the vehicle is traveling at low speed.

  In some embodiments, the off-road speed control system is operable to work with a downhill control (HDC) / hill start assistance (HHA) system to optimize the vehicle clearance even when dealing with obstacles on tight slopes. It can be. In some embodiments, the vehicle may be configured such that the braking command of the HDC / hill starting assistance (HHA) system overrides or otherwise overrides the command of the off-road speed control system. In some embodiments, such priorities may be configured to occur when the vehicle's driving gradient is greater than the pre-determined location and / or the speed is less than or equal to the pre-determined threshold. Thus, in some embodiments, the powertrain and / or brake system may respond to HDC) / hill start assistance (HHA) system commands in preference to off-road speed control system commands.

  In some embodiments, the acceleration used when accelerating the vehicle from the current set speed to the changed set speed is the off-road speed control system, one or more pre-determined performance characteristics, optionally, The terrain response system can be selected by referring to characteristics displayed based on the terrain mode. Those characteristics can be appropriately prioritized based on terrain mode changes or predicted changes. Thus, the off-road speed control system can be configured to operate alone or in cooperation with the terrain response system, but not to interfere with factors that could otherwise cause misjudgment of the terrain type.

  Embodiments of the present invention will be described below with reference to the accompanying drawings only. FIG. 14 shows a plot of the vehicle speed v and the vehicle set speed vset as a function of the distance d from the reference position when the vehicle 100 moves according to one embodiment of the present invention. The vehicle 100 encounters sandy terrain during the distances d1 and d2 from the reference position, and runs on hard terrain having a relatively low roll resistance and a relatively high surface friction coefficient before and after the sandy terrain.

  The LSP control system 12 controls the vehicle 100 so as to maintain the user's predetermined set speed vset = v2 on the terrain. When the leading wheel of the car 100 first encounters sandy terrain at a distance d1, the LSP control system 12 recognizes that the vehicle speed v has started to decrease relatively rapidly as shown by the trace v in FIG. The LSP control system 12 also recognizes that the leading wheels of the car are currently subjected to relatively high roll resistance and relatively high drag. Accordingly, the LSP control system 12 determines that it is more appropriate to travel on the sandy terrain at the slow set speed vset = 1 in order to maintain the clearness of the vehicle, and reduces the set speed to that speed. Thus, the LSP control system 12 controls the vehicle 100 in a manner that reduces the speed v to the value. Upon encountering additional roll resistance, the LSP control system 12 may increase the amount of torque P generated by the powertrain 129 as needed to maintain the new set speed v1 (as shown by the lower trace P in FIG. 14).

If the following wheel continues to encounter sandy terrain, the amount of torque applied to the following wheel is increased by a substantial amount that compensates for the high drag experienced by the following wheel.
As the car 100 continues to travel on sandy terrain, the leading wheel eventually encounters hard terrain with a low roll resistance and a large surface friction coefficient at a distance d2. When the preceding wheel contacts this terrain and the wheel grips the hard terrain, the acceleration of the vehicle 100 increases relatively rapidly. The LSP control system can detect an increase in acceleration and determine the need to reduce the powertrain torque to the preceding wheels to maintain a clear car. The LSP control system 12 then commands to reduce the powertrain torque to the preceding wheel.

  In one embodiment, the LSP control system 12 at this point is a brake that resists wheel rotation against the positive additional torque from the powertrain 129 to prevent wobbling of the leading wheel and / or the risk of exceeding the set speed. Torque can also be added to the leading wheel. This feature has the advantage that the delay in the powertrain response to the powertrain torque reduction request can be received by the LSP control system 12, thus providing a large margin for control of the vehicle 100 by the system. In one embodiment, LSP control system 12 controls vehicle 100 in a manner that reduces the length of time that acceleration exceeds a predetermined acceleration corridor.

  In some embodiments, the LSP control system 12 may cause the follower wheel to remove the sandy terrain so as to reduce the risk of wheel wobble when the follower wheel also leaves the sandy terrain and / or the vehicle's set speed vset being exceeded. It is possible to reduce the amount of torque added to the powertrain to the following wheel before leaving. In some embodiments, a brake system may be applied to the follower wheel in addition to or instead. This brake system can be applied to the following wheel when the preceding wheel encounters the new terrain, immediately before the following wheel encounters the new terrain, or when the following wheel encounters the new terrain. Other configurations are also useful.

When the vehicle exits the sandy terrain, the LSP control system 12 determines that the set speed has now returned to the value of vset = v2. Therefore, the LSP control system 12 increases the vehicle speed after the moving distance d2 to return to v = vset = v2.
In one embodiment, the LSP control system 12 predicts when the following wheels will exit sandy terrain (depending on vehicle speed and / or distance traveled since the preceding wheel encountered the new terrain and the wheelbase of the car). ), And may be operable to reduce the amount of additional torque applied to the following wheel when the following wheel leaves the sandy terrain or immediately before it exits.

  In other vehicle driving examples, the car may move from a hard tamped road surface to a softer road surface and then move back to a hard tamped road surface as previously described. As the vehicle moves on a soft road surface, the system may have a configuration that increases torque distribution to one or more following wheels to push the vehicle onto the soft road surface. Upon exiting the soft road surface, the system may be operable to distribute more additional torque to the preceding wheels to push the car harder and push it onto the road surface. The system monitors the vehicle's response to one or more external forces and distributes torque to increase vehicle clearance between each wheel.

In some embodiments, the speed control system may selectively increase the amount of torque applied to one or more wheels that are subjected to relatively high drag to compensate for the relatively high drag as previously described.
In some embodiments, the speed control system increases the torque to the wheel that is receiving high drag (to compensate for high drag / roll resistance) or increases the torque to the wheel that is receiving low drag ( It may be operable to determine whether to push or pull the car) based on which one optimizes the car's clearance. In some embodiments, if one method selected is found to be inappropriate, other methods may be tried. Other configurations are also useful.

  Certain embodiments of the present invention first detect the amount of slip when encountering a road area where one or more following wheels are known to have a low coefficient of road friction with respect to one or more preceding wheels. Predicting based on a slip event that has been made has the benefit of reducing the amount of slip of one or more following wheels relative to that of one or more preceding wheels.

The point that the system can cope with drag changes by increasing torque is to precharge the brake system so that the speed control system can respond more quickly if, for example, torque oversupply compensation is still required after overcoming an obstacle. May be an appropriate indication of
The embodiment of the present invention can significantly reduce the tire corrosion effect on an off-road route, and can improve tire wear and fuel consumption. Embodiments of the present invention adapt to sudden or sudden changes in drag or other forces acting on the vehicle due to terrain changes under the control of the vehicle's off-road speed control system and resist vehicle speed overshoots. The space can be further improved.

9. A-323 Automatic Powertrain Torque Ceiling Management By using a speed control system at low speed when driving off-road, the user has a considerable benefit due to reduced vehicle user workload and increased vehicle clearance. Can be provided. However, the allowable powertrain torque addition amount by the speed control system may be limited in the operation of the powertrain. This is typically because the maximum torque capacity of the powertrain is fixed. This restriction is imposed to meet special rules regarding the use of the speed control system on the road and the accelerations that the speed control system can command during operation on the road. However, artificially applied torque limits or round-ups can limit off-road performance.

  Optionally, the off-road speed control system of an embodiment includes, among other things, information about the vehicle's travel terrain, vehicle attitude, wheel movement, wheel speed, gear selection, tire friction, tire drag, roll resistance, and selected Data relating to at least one selected from the TR mode is provided.

  An off-road speed control system of an embodiment of the present invention obtains information about the settings of one or more vehicle systems or subsystems, and optionally data about the performance of the vehicle. It has the structure which judges whether it is drive | working off-road. Once the off-road speed control system is activated and the vehicle is confirmed to be off-road, the predetermined powertrain torque limit is applied until the system determines that more torque (exceeding the predetermined limit) is required. To do. The system may determine whether more torque is required, for example with reference to a vehicle response to the torque request.

  Torque above the torque limit may be required under certain conditions for the car to deal with rocks, hard slopes or other obstacles such as terrain, or to complete the negotiation. The predetermined torque limit in normal off-road speed control conditions may correspond to, for example, that given for on-highway speed control operation, or any other suitable value.

  When an off-road speed control system determines that a torque increase is required, it may temporarily increase the available torque limit to overcome or otherwise cope with an obstacle, slope or other terrain. Can be judged appropriate.

  As explained above, in certain embodiments, the “normal” torque limit is determined by the system to require more torque (exceeding the torque limit) to maintain proper progression (eg, for torque demand). This applies to the amount of torque that the powertrain can generate (from the car's reaction). The system then temporarily increases the available torque limit when it determines that it is appropriate to overcome or otherwise cope with the obstacle.

In one embodiment, the offload speed control system includes the following checks:
(A) Confirmation of vehicle speed <target set speed (the user set speed and below the maximum set speed given by the speed control system),
(B) confirmation that the powertrain torque is the first limit value;
(C) The off-road speed control system is activated in a state where the power train torque is output at a predetermined first power train torque limit value for a time exceeding a predetermined time length or a predetermined engine speed. Confirmation,
(D) Confirm that the user has operated a braking control device such as a brake pedal, for example, the brake pedal is not depressed,
(E) Other user intervention (in some embodiments, an example of such intervention is a speed control system via a user's acceleration control device, in some embodiments a “-” button, and in some embodiments via a brake pedal). (In addition or alternatively, the system may also check that the speed controller “cancel” button has not been pressed. In certain embodiments, the system may add or Alternatively, it can also be checked that the speed controller activation button has not been pressed during speed control system operation (this is to indicate the user's desire to cancel speed control system operation) In one embodiment, the system is Downhill control (HDC) or similar functions that limit or limit the movement of the car May check the deactivation. System may be configured not to act like can act against the action of HDC or similar system.)
(F) Confirmation that the steering wheel angle is not more than a predetermined threshold value,

(G) Check if the car's posture shows that the car is going downhill (if so, the system will then return the grip to one or more wheels to normal) And / or braking torque application is sufficient to compensate for powertrain overrun and maintain vehicle clearance if the drag experienced by one or more wheels subsequently drops to normal. The system can determine this on the basis that the slope the vehicle is currently encountering is maintained when the grip value is restored or when the drag is released. If it is determined that sufficient negative torque cannot be applied, the system may refuse to increase the powertrain torque limit on the way downhill, in terms of clearance, the system will be in the accelerated corridor (eg 0.2 g) range. Fit in Not tolerate more acceleration to set speed at a high rate, it does not allow an increase in the vehicle speed over a user set speed (that is, the vehicle set speed overshoot).)
(H) confirming that the brake system is functioning properly and is ready;
After executing at least one of the above, the power train torque may be increased to a predetermined limit value or more.

  In some embodiments, the off-road speed control system may be operable to check the selected TR mode if the vehicle is equipped with a TR system. A determination that the increase in powertrain torque limit is one of the vehicles under a predetermined set of one or more TR modes (or under a non-predetermined set of one or more TR modes) Can be a target. For example, if the selected TR mode corresponds to driving on a relatively slippery road surface (such as a “snow / ice” mode), an increase in powertrain torque limit may be prohibited in certain embodiments. Other configurations are also useful.

  In some embodiments, an increase in the powertrain torque limit value may be allowed, but an allowable rate of increase in the powertrain torque may be limited. Thus, in an embodiment, if it is determined that the vehicle is being driven on a slippery road surface but an increase in powertrain torque is not desirable, the increase may be a new increase in powertrain torque and / or powertrain torque. It can be allowed under limited conditions with respect to the maximum allowable value.

  In some embodiments, if it is detected that the vehicle is in the process of being negotiated, the off-road speed control system increases the amount of exhaust gas passing through the engine aftertreatment system so that the liquid that the car is in transit to the aftertreatment system is increased. It may be operable to increase the powertrain torque limit to reduce the risk of inflow and damage. Catalytic converters and / or particle filters associated with aftertreatment systems can be particularly vulnerable to water exposure during transit.

  In some embodiments, the off-road speed control system may temporarily interrupt or change one or more driving parameters to reduce parasitic losses to generate more torque than the wheel has available. Can interact with other car systems.

  In some embodiments, the offload speed control system allows the user to implement an informed choice about whether to reroute, manually intervene, or allow management of obstacle handling by the system itself. Can inform the user that more torque is needed. In some embodiments, if an increase in powertrain torque limit by the speed control system cannot be permitted, canceling the off-road speed control function will allow the user to have power above a predetermined powertrain torque limit associated with speed control system operation. It may be possible to request a train torque.

An off-road speed control system according to an embodiment of the present invention may be an ATPC (which may be alone or combined with a vehicle control system configured to optimize the vehicle for a predetermined terrain on which the vehicle travels. May be part of a system. An example of such a system is Terrain Response (trade name) as described above.
In some embodiments, the off-road speed control system controls or otherwise affects gear selection, such as transmission gear and / or “high / low” ratio selection, if that functionality is available. Can be actuated to

  The increased powertrain torque limit value may be reduced based on the off-road speed control system's determination that the vehicle acceleration rate exceeds a predetermined threshold. This feature can be beneficial in increasing vehicle clearance. Measurement of vehicle acceleration may act as vehicle motion determination means independent of one or more wheel speed sensors. Acceleration measurements may be beneficial if the wheel speed sensor readings appear to be inconsistent, optionally if the two wheel speed readings do not match each other.

  In some embodiments, the increase in torque limit is a preset performance characteristic indicated by the Terrain Response ™ system, optionally based on the selected terrain mode, and more optionally, in the terrain mode. It can be influenced by preset performance characteristics that can be appropriately prioritized based on changes or predicted changes. Thus, the off-road speed control system can be configured alone or in combination with the TR system, but can be configured not to interfere with factors that can cause misjudgment of terrain type.

  The present invention will now be described with reference to the accompanying drawings only. In particular, FIG. 15 illustrates an aspect in which the amount of torque generated by the vehicle powertrain 129 can be controlled by the LSP control system 12 according to one embodiment of the present invention. In the illustrated example scenario, the vehicle 100 is moving on the terrain under the control of the LSP control system 12. When the vehicle 100 moves from the reference position (d = 0) to the distance d = d1 under the control of the LSP control system 12, the powertrain is torqued to maintain the set speed v = vset = v2 (shown in FIG. 15). The quantity P = P1 is generated.

  As the vehicle 100 moves beyond the distance d = d1, it encounters a sandy terrain, and this terrain increases the amount of drag on the vehicle 100. The LSP control system 12 detects an increase in drag, at least in part, due to a decrease in the travel speed v of the car 100. Then, the LSP control system 12 increases the output amount of the power train 129 to recover the speed v = vset. The LSP control system 12 in the illustrated example increases the powertrain torque to P2, which is a value corresponding to the default powertrain maximum allowable torque, when it is activated. The LSP control system 12 continues to monitor the speed v and determines that the vehicle speed v = v1 <vset.

  The LSP control system 12 maintains the powertrain torque at P1 for a predetermined time length of 5 seconds in this embodiment, but other values are useful. After 5 seconds, the car is at a distance d2 from the reference position and is moving at a vehicle speed v <vset. The LSP control system 12 further confirms whether or not the user has stepped on the accelerator pedal 161 or the brake pedal 163 to intervene in the vehicle progress control after a predetermined minimum time has elapsed, and in the illustrated example, the power train torque is set to the default maximum torque. It is determined that the increase of the value P2 can be permitted.

  Thus, the LSP control system 12 determines that the power train torque increase to the value P4 can be permitted, and starts the power train torque increase. The LSP control system 12 increases the powertrain torque and monitors the vehicle speed v, and controls the vehicle 100 to realize the user set speed v = vset. In the example of FIG. 15, the vehicle 100 realizes the user set speed v = vset and maintains this speed under the condition that the powertrain torque P = P3 <P4.

  At a distance d = d3, the leading wheel of the car 100 exits sandy terrain and encounters a relatively hard road surface with a relatively low roll resistance and a relatively high surface friction coefficient. The LSP control system 12 determines that the vehicle speed v is currently increasing relatively rapidly, and commands a decrease in powertrain torque to maintain v = vset. The LSP control system 12 also commands the addition of a brake system to one or more preceding wheels of the vehicle 100 to attempt to prevent excessive overshoot of the vset while the powertrain is decreasing. The braking system can respond much faster to torque commands than the powertrain due to the rotational inertia of the powertrain 129, making it ideal for limiting set speed overshoots such as when moving from a high drag road to a low drag road .

At distance d = d4, the powertrain torque P is returned to a reduced approximately P1 value sufficient to maintain the vehicle set speed v = vset = v2 on the terrain encountered at distance d> d4.
In some embodiments, the vehicle 100 can be operated in an off-road speed control mode in either a forward or reverse driving direction.

  An embodiment of the present invention can significantly reduce the tire corrosion effect on an off-road route, and can improve tire wear and fuel consumption. Embodiments of the present invention adapt to sudden or sudden changes in drag or other forces acting on the vehicle due to terrain changes under the control of the vehicle's off-road speed control system and resist vehicle speed overshoots. The space can be further improved.

10. A-324 User Configurable Travel Control Using a speed control system at low speeds during off-road driving can provide users with significant benefits due to reduced vehicle user workload and increased vehicle clearance . However, the speed control system, which is configured to work off-road, allows a vehicle to maintain a certain speed on various terrains, and the ride comfort on one road surface is different when driving at the same speed. Points that can be much worse than that on the road are not taken into account.

  An embodiment of the present invention provides an off-road speed control system configured to allow a user to drive a vehicle at a low speed while the off-road speed control system adjusts the vehicle speed to a set speed selected by the user. Provided.

In some embodiments, the off-road speed control system considers at least one selected from road roughness, wheel slip, wheel movement, among others, when determining the maximum speed that the system can drive the car on the road. It is supposed to be configured.
Under certain conditions, maximum vehicle speed reduction through speed control system intervention may be useless for some users and sufficient for other users.

  The off-road speed control system according to the present invention is intended to increase the off-road driving performance by reducing the amount of user work and increasing the clearance of the vehicle. The level of car clearance can affect all occupants, not just those who control driving.

  In some embodiments, among other things, from the terrain on which the vehicle travels, the attitude of the vehicle, wheel movement, wheel speed, road surface roughness, gear selection, tire wear, tire drag, roll resistance, TR mode information or data An offload speed control system is provided in which at least one selected is provided.

  In some embodiments of the invention, the system is further provided with memory, user-operated input means such as a switch, processor, and seat utilization data. The off-road speed control system is operable to adjust the comfort setting of the speed control system as the setting used by the system to determine how much the vehicle speed is slower than a given set speed for a given road condition or terrain It can be. The system may be operable to adjust comfort settings based on data regarding seat utilization and input signals received from user-operated input means.

  In operation, the system records in memory how the user has adjusted the comfort settings of the off-road speed control system for a given amplitude and frequency of vehicle vibration caused by the terrain roughness the vehicle is driving. It has the composition to do. If the system determines that the body vibration is similar to or otherwise matches the sample stored in memory, the processor temporarily generates a default baseline set speed limit that is less than or equal to the speed control set speed previously set by the user. The temporary default baseline setting speed limit is set by the system during a specific section of the terrain where the vehicle is driven unless disabled by the user.

  When the user disables the system, the system may store data corresponding to the disabled fact in memory. A look-up table storing data relating to the user's requested vehicle speed as a function of vehicle vibration characteristic data is updated. In some embodiments, the speed control system updates the stored data only when the user repeatedly disables the system.

  In some embodiments of the invention, if the off-road speed control system adjustment for a particular user tends to disable the automatic speed reduction feature in an attempt to increase speed, the off-road speed control system may It may be configured to employ a user-defined baseline speed limit that is higher than the default baseline set speed limit. That is, the speed limit that the system can degrade when encountering such terrain is much higher than the default baseline speed limit for those terrain types. As described above, in one embodiment, the terrain “type” is one for a predetermined selected TR mode, with the amplitude and frequency of vehicle vibration, optionally, vehicle movement, optionally in addition or alternatively. Or it can be quantified with reference to one or more other parameters, such as one or more parameter values.

  In some embodiments, the user-defined baseline speed limit can be manually reset by the user to adopt a default value for the maximum offload speed control speed that may be slower than the user-defined baseline speed. In some embodiments, this default value may actually be faster than a user-defined speed.

In some embodiments, in addition or alternatively, the vehicle may be operable to detect that the vehicle is traveling with one or more passengers in the vehicle using an off-road speed control system. If so, the system may be operable to reset the user-defined baseline offload speed control system speed to the default baseline speed limit.
In scenarios where an off-road speed control system is typically used when the user is driving alone, the user may accept a reduction in vehicle clearance due to the car traveling at a higher speed on a given road surface. . When the user controls the car, the operation of the car feels as expected and is acceptable. Furthermore, the driver can stabilize himself / herself with respect to the steering wheel, so that it can withstand larger body movements that would be comfortable for the occupant. For passengers who do not control the car, the same movement or vibration of the car will be unacceptably uncomfortable. To compensate for this, in one embodiment, if the system determines that the number of occupants in the car is one or more, the system will adjust the comfort and comfort-oriented speed adjustment mode until the user manually overrides the setting. (Maximum speed is equivalent to default baseline setting speed limit, for example).

  The speed control system is operable to monitor one or more parameters that affect vehicle body movement and thus occupant comfort, such as steering wheel angle or steerable wheel angle and / or rate of change thereof. possible. The system monitors data representing road surface roughness and converts this data into data such as steering wheel angle or steerable wheel angle, or their rate of change, which can affect one or more vehicle parameters. It can be actuated to associate. If the user disables the speed control system and indicates that he / she feels too fast, the system will disable the system due to characteristics of the vehicle's driving terrain or other factors that affect the body movement. It can be determined whether or not the selection is made. An example of such a factor is an operation by the driver, such as a sudden turning of the steering wheel on the terrain that would otherwise not cause excessive discomfort to the user. In some embodiments, the system is more sensitive to tilting about the longitudinal axis of the car and the terrain is relatively smooth when the car travels across a car roll angle, eg, a slope. Even if this is the case, it may require the system to reduce the set speed.

  The speed control system records data that displays the steering wheel angle or steerable wheel angle, or their rate of change, or both, and optionally the vehicle roll angle, lateral acceleration, etc. Is the fact that you have chosen to disable the speed control system to reduce the set speed is due to terrain roughness alone, or a combination of terrain roughness and one or more parameters that affect vehicle behavior Can be determined. The system may be configured to take into account whether the occupant is on board during user intervention to reduce the set speed. If the occupant is not in the vehicle, the car will determine that the set speed can be reduced to a level even lower than if one passenger is in the vehicle when a similar scenario is encountered with a passenger in the future. obtain. The system further predicts that if a reduction in one or more parameter values that affect the roll of the car body is detected in the future, the occupant will not be able to withstand a particular car movement more than the driver's set speed. May be operable to reduce Furthermore, if there is one or more passengers, the center of gravity of the car will rise, and the movement of the vehicle body when moving on specific terrain may tend to be large, so such an action is also sensitive. obtain. Thus, body movements while the vehicle is under the control of the system 12 will manage the specific factors that may affect or otherwise affect the comfort of each occupant of the vehicle, which would like to maintain good off-road progress. Managed at least in part by harmonizing with requirements.

  The present invention will now be described with reference to the accompanying drawings only. FIG. 16 (a) shows a console 184 of a car 100 according to an embodiment of the invention having a user-configurable progress control device. The console has user operated buttons 187 that, when pressed by the user, provide control signals to a processor 185 associated with the LSP control system 12. The processor is operable to store and retrieve data from memory 186, also associated with LSP control system 12.

  The LSP control system 12 is operable to receive data indicating car seat usage. That is, it is data that displays whether a predetermined seat of a car other than the driver's seat is being used. FIG. 16B shows a plan view of the cabin of the vehicle according to the embodiment of the present invention showing the seats 101S to 105S. The LSP control system 12 receives data corresponding to the state of the switch embedded in the seat belt buckle 106 related to each of the seats 101S to 105S. When the switch enters a state indicating that the buckle 106 has been fastened, the LSP control system 12 considers that the seat associated with this buckle has been utilized. If the switch enters a state indicating that the buckle 106 is not fastened, the LSP control system 12 considers that the seat associated with the buckle 106 is not utilized. Seat use can be determined by sensors in each seat or by an infrared or visible light camera configured to observe the cabin. Other means for determining seat usage are also useful. Memory 186 may be partitioned for data storage regarding a plurality of known drivers and their associated preferences. The system may, among other things, have a configuration for authenticating the driver with a single authentication selected from seat adjustment positions, user-defined key fob authentication, or other known means.

  In an embodiment, the maximum speed (set speed limit) automatically given by the system can be automatically adjusted by the system according to the determination of whether the vehicle body acceleration exceeds the pre-determination threshold based on the running time and behavior of the vehicle. This can be used to increase the clearance of the vehicle and acts as a means of determining the operation of the vehicle independent of the output of one or more wheel speed sensors. This can be beneficial if the speed readings of the two wheels do not match each other.

This feature can be applied uniformly to a number of vehicles with different suspension spring / damper settings, and can also be used in vehicles whose characteristics can change over time. By using vehicle acceleration measurements, the speed control system can be freed from constraints on a particular vehicle or suspension type.
In some embodiments, the off-road speed control system may be operable when used for either forward or backward travel.

  An off-road speed control system according to an embodiment of the present invention is configured to optimize a vehicle, such as one or more subsystem configurations, alone or for a predetermined terrain on which the vehicle travels. It may constitute part of an ATPC (All Terrain Progressive Control) system that may be combined with the above vehicle control system. An example of such a system is the Terrain Response ™ system as described above.

  Embodiments of the present invention have the benefit of substantially improving vehicle clearance. In particular, certain embodiments of the present invention may be used in a particular user when this user is driving alone, because the level of vehicle clearance that one or more passengers can withstand may differ from that a user can withstand, and , Increase the fun of the car when this user carries a passenger.

The above-described embodiments have been described for illustrative purposes only and are not intended to be limiting and the scope thereof is defined in the appended claims.
Throughout the description and claims of this specification, “including” and “contains” and their derivatives, eg, “wrapping” and “including”, mean “including but not limited to”. It is not intended to exclude other parts, additional parts, components, integers, or steps.

  Throughout this description and the claims, the singular includes the plural unless the context requires otherwise. Specifically, where an indefinite article is used, the singular form of the specification shall include the plural, unless the context requires otherwise.

  Any feature, integer, characteristic, formulation, chemical ingredient or group described in connection with a particular aspect, embodiment or example of the invention, is optional as long as it is not incompatible therewith. It can be applied to other aspects, embodiments or examples.

  To avoid misunderstanding, each aspect or embodiment of the invention described above with the addition of numbers 1 to 10 is the other one of those aspects or embodiments unless otherwise specified. It should be understood as necessarily including one or more of the features described for one or more. The aspects or embodiments of the present invention described in one or more of the aspects or embodiments of the present invention described with the numbers 1 to 10 are the books described with the numbers 1 to 10 added. The invention may be applied to any other embodiment as long as it is in each aspect of the invention or one or more of the embodiments, or is not incompatible therewith. . In each aspect or embodiment of the present invention described with reference to numbers 1 to 10, the reference to the features of the common figure such as FIG. 1 or other drawings is the same as the aspect or embodiment described in the item. It should not be construed as requiring that the features described with respect to the common graphics also be included.

DESCRIPTION OF SYMBOLS 12 Control system 12 LSP control system 16 Cruise control system 21 Signal line 22 Brake system 28 Comparator 30 Output signal 34 Vehicle speed sensor 36 Measurement vehicle speed 38 Target vehicle speed 40 Evaluator unit 42 Output 48 Wheel slip signal 100 Car 101S-105S Seat 106 Seat belt buckle 111-115 Wheel 118 Front drive shaft 121 Engine 124 Transmission / gear box 129 Power train 130 Auxiliary drive line 132 Propeller shaft 135 Rear differential 137 Front differential 139 Rear drive shaft pair 161 Accelerator pedal 161 Brake pedal 163 Brake pedal 171 Steering wheel 173 Set speed controller 174 “+” controller 184 console 185 processor 186 memory 187 user-operated buttons

Claims (30)

A vehicle speed control system for a vehicle having a plurality of wheels,
It has a configuration that automatically controls the vehicle speed to the target set speed,
Means for applying torque to at least one of the plurality of wheels;
Means for detecting a slip event between one or more wheels during operation of the vehicle and a road surface on which the vehicle travels, and providing a slip detection output signal upon detection of the slip event;
Means for receiving user input of a target set speed for driving the car;
Means for applying torque to at least one of the plurality of wheels to maintain the vehicle at a target set speed independent of the slip detection output signal;
Including vehicle speed control system. Means for applying a torque to at least one of a plurality of wheels to maintain the vehicle speed at a target set speed;
Means for determining the current speed of the traveling vehicle;
Means for comparing the current speed with the target set speed and providing an output indicating the difference between the current speed and the target set speed;
Means for evaluating a torque to be applied to at least one of the wheels of the vehicle based on the output;
The vehicle speed control system according to claim 1, comprising:   The vehicle speed control system according to claim 2, wherein the means for applying torque to at least one of the plurality of wheels has a configuration for simultaneously applying torque to at least two wheels of the vehicle.   4. The vehicle speed control system according to claim 3, wherein the means for applying torque to at least one of the plurality of wheels has a configuration for simultaneously applying torque to at least four wheels of the vehicle.   The vehicle speed control system according to any one of claims 2 to 4, further comprising means for disturbing the operation of the vehicle control system when it is determined that the current speed exceeds a predetermined threshold speed.   6. The vehicle speed control system according to claim 5, wherein the predetermined threshold speed is between about 40.2 to about 56.3 km / h (25 to 35 mph).   7. The vehicle speed control system according to claim 6, wherein the predetermined threshold speed is substantially about 48.27 km / h (30 mph). The predetermined threshold speed is the first low speed side threshold speed,
The vehicle speed control system
The current vehicle speed is compared with the second high speed side threshold speed. If the current vehicle speed is less than the second high speed side threshold speed, the vehicle speed control system is held in a standby state, and the current vehicle speed is set to the first low speed side threshold speed. The vehicle speed control system according to any one of claims 5 to 7, further comprising means for starting the vehicle speed control only in a case where the speed falls below.   The vehicle speed control system according to any one of claims 5 to 8, further comprising a cruise control system operable to maintain the vehicle speed above a predetermined threshold speed.   The vehicle speed control system according to claim 9, wherein the cruise control system includes means for interrupting the operation of the vehicle speed control system when receiving the slip detection output signal. Means for detecting the terrain characteristics on which the vehicle travels,
Means for determining whether the target set speed is appropriate for the terrain characteristics of the vehicle traveling;
11. The apparatus according to claim 1, further comprising means for applying torque to at least one of the plurality of wheels to maintain the vehicle at the target set speed only when it is determined that the target set speed is appropriate. Vehicle speed control system. A vehicle speed control system for a vehicle having a plurality of wheels,
Means for applying torque to at least one of the plurality of wheels;
Means for receiving user input of a target set speed for driving the car;
Means for determining terrain characteristics of the vehicle, including a plurality of sensors for displaying the movement of the vehicle body;
Means for determining whether the target set speed is appropriate for the terrain characteristics of the vehicle traveling;
Means for applying torque to at least one of the plurality of wheels to maintain the vehicle at the target set speed only when it is determined that the target set speed is appropriate;
Including vehicle speed control system.   Means including a plurality of sensors for displaying the movement of the vehicle body, and determining the terrain characteristics on which the vehicle travels is an ambient temperature sensor, an atmospheric pressure sensor, a tire pressure sensor, a yaw sensor for detecting the yaw, roll and / or pitch of the car, inclination 13. A vehicle speed control system according to claim 11 or 12, comprising one or more of the sensors.   A vehicle comprising the vehicle speed control system according to claim 1. A method of automatically controlling the speed of a vehicle having a plurality of wheels to a target set speed,
Applying torque to at least one of the plurality of wheels;
Detecting a slip event between one or more of the wheels and the road surface on which the operating vehicle travels, and providing a slip detection output signal upon detection of the slip event;
Receiving a user input of a target set speed for driving the car;
Automatically maintaining the vehicle at a target set speed independent of the slip detection output signal by applying torque to at least one of the plurality of wheels;
Including methods. Automatically applying the torque to at least one of the plurality of wheels to automatically maintain the vehicle at the target set speed regardless of the slip detection output signal;
Determining the current speed of the traveling vehicle;
Comparing the current speed with the target set speed and outputting a signal representing the difference;
Evaluating the torque applied to at least one of the wheels of the vehicle based on the output signal;
The method of claim 15 comprising:   The method of claim 16, comprising simultaneously applying torque to at least two wheels of the vehicle.   The method of claim 17, comprising simultaneously applying torque to at least four wheels of the vehicle.   19. A method according to any of claims 16-18, further comprising the step of interfering with the operation of the speed control system if it is determined that the current speed is above a predetermined threshold speed.   20. The method of claim 19, wherein the predetermined threshold speed is between about 40.2 and about 56.3 km / h (25-35 mph).   21. The method of claim 20, wherein the predetermined threshold speed is substantially about 30.mph. The predetermined threshold speed is the first low speed side threshold speed,
The current vehicle speed is compared with the second high speed side threshold speed. If the current vehicle speed is less than the second high speed side threshold speed, the vehicle speed control system is held in a standby state, and the current vehicle speed is set to the first low speed side threshold speed. The method according to any one of claims 19 to 21, further comprising a step of starting the vehicle speed control only in the case of the following decrease.   23. A method according to any one of claims 19 to 22, further comprising the step of operating the cruise control system to maintain the vehicle speed above a predetermined threshold speed.   24. The method of claim 23, further comprising interrupting operation of the cruise control system upon receipt of a slip detection output signal. Detecting the terrain characteristics on which the car travels,
Determining whether the target set speed is appropriate for the terrain characteristics of the vehicle traveling;
Adding torque to at least one of the plurality of wheels and maintaining the vehicle at the target set speed only if it is determined that the target set speed is appropriate;
The method according to any one of claims 15 to 24, comprising: A method of automatically controlling the speed of a vehicle having a plurality of wheels to a target set speed,
Applying torque to at least one of the plurality of wheels;
Receiving a user input of a target set speed for driving the car;
Determining terrain characteristics on which the vehicle travels based on one or more signals representing vehicle motion received from a plurality of sensors;
Determining whether the target set speed is appropriate for the terrain characteristics on which the vehicle is traveling;
Adding torque to at least one of the plurality of wheels and maintaining the vehicle at the target set speed only if it is determined that the target set speed is appropriate;
Including methods.   The step of determining terrain characteristics is determined based on a signal received from one or more of an ambient temperature sensor, an atmospheric pressure sensor, a tire pressure sensor, a yaw sensor for detecting the yaw, roll and / or pitch yaw of a car, and a tilt sensor. 27. A method according to claim 25 or 26.   A vehicle comprising the speed control system according to any one of claims 1 to 27.   A carrier medium carrying a computer readable code for performing the method according to any of claims 15 to 28 to control a vehicle.   A method, system or vehicle substantially as herein described.

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