JP7399562B2 - Follow-up travel control device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a follow-up travel control device that causes a vehicle to follow a preceding vehicle.

Recent vehicles have been equipped with a so-called adaptive cruise control (ACC) function, which allows the vehicle to follow a preceding vehicle in front of it.

While the adaptive cruise control function is in operation, the distance between the own vehicle and the preceding vehicle to be followed is maintained at an appropriate distance using the vehicle speed set by the vehicle user (driver) as the upper limit of the own vehicle's vehicle speed. The vehicle automatically accelerates and decelerates. When the preceding vehicle stops, the own vehicle automatically stops with an appropriate distance between the vehicle and the preceding vehicle.

With the conventional adaptive cruise control function, once both the own vehicle and the vehicle in front have stopped, the following cruise control, which causes the vehicle to follow the vehicle in front, does not automatically resume even if the vehicle in front starts moving. . Therefore, a technology has been proposed in which a start/stop switch is provided near the steering wheel, and when the start/stop switch is turned on, the following cruise control is automatically restarted in response to the start of the preceding vehicle ( For example, see Patent Document 1).

Japanese Patent Application Publication No. 2005-247197

However, in vehicles that employ this technology, users may not remember the function of the start/stop switch, and the function of restarting follow-up control in response to the start of the preceding vehicle may not be utilized.

Furthermore, if the user visually confirms the position of the start/stop switch when operating the start/stop switch, the user's line of sight may shift from the front to the hand, and the user's attention may be diverted from the front.

An object of the present invention is to provide a following cruise control device that can improve the degree of utilization of the function of restarting following cruise control in response to the start of a preceding vehicle.

In order to achieve the above object, the following cruise control device according to the present invention includes an accelerator operation detection means for detecting an accelerator operation and a following cruise function that is effective, and when there is a preceding vehicle to be followed in front of the host vehicle. In this case, the following driving control execution means for executing the following driving control that causes the own vehicle to follow the preceding vehicle and the following driving function are enabled, and the accelerator is operated when the own vehicle and the preceding vehicle are stopped. a driving force suppressing means that, when an accelerator operation is detected by the detection means, processes the accelerator operation as a control restart request operation and suppresses the driving force for driving the own vehicle; If the process is processed, the control restart means cancels the suppression of the driving force by the driving force suppressing means and causes the following traveling control execution means to resume execution of the following traveling control in response to the start of the preceding vehicle.

According to this configuration, when the following driving function is enabled and there is a preceding vehicle to be followed in front of the own vehicle, the following driving control is executed to cause the own vehicle to follow the preceding vehicle in front of it. Ru. If the following driving function is enabled and the accelerator is operated while the own vehicle and the preceding vehicle are stopped, the accelerator operation is processed as a control restart request operation, and the driving force for driving the own vehicle is reduced. suppressed. If the accelerator operation is processed as a control restart request operation, the suppression of the driving force is canceled in response to the start of the preceding vehicle, and the execution of the follow-up travel control is resumed. As a result, the own vehicle starts following the preceding vehicle.

If the start/stop switch located near the steering wheel is turned on, the follow-up control is restarted when the vehicle in front starts, and the start/stop switch is activated. Since the relevance is low and it is difficult for the user to remember the function of the start/stop switch, the function of restarting the follow-up driving control in response to the start of the preceding vehicle may not be utilized. On the other hand, in a configuration in which the following driving control is restarted in response to the start of the vehicle in front when the accelerator is operated, the user can operate the accelerator when the vehicle starts in response to the start of the vehicle in front. It is intuitively understood and easy to remember as an operation that requests the resumption of follow-up control. Therefore, it is possible to improve the degree of utilization of the function in which the follow-up cruise control is restarted in response to the start of the preceding vehicle.

In addition, if the accelerator operation is processed as a control restart request operation, the driving force for driving the own vehicle is suppressed, so the movement of the own vehicle in response to the accelerator operation can be suppressed, and the own vehicle This can prevent collisions with vehicles in front.

Moreover, since the user does not need to move his or her line of sight to operate the accelerator, it is possible to prevent the user's attention from straying from the front.

When the following function is enabled and the own vehicle and the preceding vehicle are stopped and the preceding vehicle starts without accelerator operation being detected by the accelerator operation detection means, the following cruise control device changes the own vehicle to the set vehicle speed. The configuration may further include constant speed driving control execution means for executing constant speed driving control to cause the vehicle to travel at a constant speed.

With this configuration, even if the user forgets to operate the accelerator to request resumption of follow-up control in response to the start of the preceding vehicle, the own vehicle will start when the preceding vehicle starts. This can prevent the vehicle from continuing to stop.

According to the present invention, it is possible to improve the degree of utilization of the function in which the follow-up cruise control is restarted in response to the start of the preceding vehicle.

FIG. 1 is a block diagram showing the configuration of main parts of a vehicle equipped with a follow-up cruise control device according to an embodiment of the present invention. 3 is a flowchart (Part 1) showing the flow of ACC control processing. 12 is a flowchart (Part 2) showing the flow of ACC control processing. 3 is a flowchart showing the flow of ACC termination processing.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

<Vehicle electrical configuration>
FIG. 1 is a block diagram showing the configuration of main parts of a vehicle 1 equipped with a follow-up cruise control device according to an embodiment of the present invention.

The vehicle 1 is an automobile that uses an engine 2 as a driving source. Power from the engine 2 is transmitted to left and right drive wheels via a transmission 3.

The engine 2 is, for example, a gasoline engine, and includes an electronic throttle valve for adjusting the amount of intake air into the combustion chamber of the engine 2, an injector (fuel injection device) for injecting fuel into the intake air, and an electric discharge in the combustion chamber. A spark plug or the like is provided to generate the spark. Further, the engine 2 is provided with a starter for starting the engine.

The transmission 3 may be a continuously variable transmission (CVT), a stepped automatic transmission (AT), or a manual transmission (MT). ).

In the cabin of the vehicle 1, an accelerator pedal that is operated to accelerate or decelerate the vehicle 1 and a brake pedal that is operated to brake the vehicle 1 are provided under the feet of the driver's seat. The accelerator pedal and the brake pedal are arranged at positions convenient for the user (driver) seated in the driver's seat to press the pedals with the right foot.

Further, the vehicle 1 is equipped with a hydraulic brake. The hydraulic brake includes a brake booster, a master cylinder, and a brake actuator 4. When the brake pedal is depressed, the pedal force input to the brake pedal is transmitted to the brake booster. The pedal force transmitted to the brake booster is amplified (boosted) by the negative pressure of the brake booster, and is input from the brake booster to the master cylinder. In the master cylinder, hydraulic pressure is generated according to the force input from the brake booster. The hydraulic pressure generated by the master cylinder is transmitted to the brake actuator 4. The function of the brake actuator 4 distributes hydraulic pressure to the wheel cylinders of the brakes provided on each wheel, and the hydraulic pressure applies braking force from each brake to the wheels including the driving wheels.

The vehicle 1 is equipped with an ECU (Electronic Control Unit) 5 that includes a microcomputer (microcontroller unit). A microcomputer includes, for example, a CPU, a nonvolatile memory such as a flash memory, and a volatile memory such as a DRAM (Dynamic Random Access Memory). Although only one ECU 5 is shown in FIG. 1, the vehicle 1 is equipped with a plurality of ECUs having the same configuration as the ECU 5 in order to control each part. A plurality of ECUs including the ECU 5 are connected to enable bidirectional communication using a CAN (Controller Area Network) communication protocol.

The ECU 5 incorporates engine control logic, shift control logic, and brake control logic. The engine control logic adjusts the start, stop, output, etc. of the engine 2 based on detection signals input from various sensors connected to the ECU 5 and information input from other ECUs, so the electronic throttle valve, injector, etc. and spark plugs, etc. are controlled. Furthermore, the shift control logic controls the shift of the transmission 3 based on detection signals input from various sensors and information input from other ECUs. The brake actuator 4 and the like are controlled by the brake control logic in order to adjust the vehicle speed, attitude, etc. of the vehicle 1 based on detection signals input from various sensors and information input from other ECUs.

The various sensors include, for example, an accelerator sensor 6, a brake sensor 7, a vehicle speed sensor 8, and a preceding vehicle detection sensor 9.

The accelerator sensor 6 outputs a detection signal according to the amount of operation of the accelerator pedal. From the detection signal of the accelerator sensor 6, the ECU 5 determines the ratio of the operation amount to the maximum operation amount of the accelerator pedal, that is, when the accelerator pedal is not depressed, it is 0%, and when the accelerator pedal is depressed to the maximum, it is 100%. Find the accelerator opening degree, which is the percentage of

The brake sensor 7 outputs a signal corresponding to the amount of operation of the brake pedal as a detection signal. If the level of the detection signal from the brake sensor 7 is above a predetermined level, the ECU 5 determines that the brake operation is being performed (on), and if the level of the detection signal from the brake sensor 7 is below the predetermined value, the ECU 5 determines that the brake operation is being performed (on). It is determined that this is not done (off). The brake sensor 7 may be a switch that outputs an on signal as a detection signal when the amount of operation of the brake pedal is equal to or greater than a predetermined amount, and outputs an off signal as a detection signal when the amount of operation of the brake pedal is less than a predetermined amount. .

The vehicle speed sensor 8 includes, for example, a rotor made of a magnetic material that rotates as the vehicle 1 travels, and an electromagnetic pickup provided without contact with the rotor, and receives an output from the electromagnetic pickup each time the rotor rotates by a certain angle. Outputs a pulse signal. The frequency of this pulse signal corresponds to the actual speed of the vehicle 1. The ECU 5 determines the frequency of the signal input from the vehicle speed sensor 8, and converts the frequency into a vehicle speed.

The preceding vehicle detection sensor 9 is a sensor that detects a preceding vehicle ahead of the vehicle 1, and is, for example, a radar. The radar is installed at the front of the vehicle 1 and is a sensor for detecting the situation in a predetermined search range in front of the vehicle 1. A radar irradiates a search range with radar waves, receives reflected waves from objects existing within the search range, and outputs a detection signal according to the reflected waves. The radar may be a millimeter wave radar that uses radio waves in the millimeter wave band as radar waves, or a laser radar that uses a laser as radar waves. Furthermore, the preceding vehicle detection sensor 9 may be an ultrasonic sensor or a stereo camera.

The vehicle 1 is equipped with an ACC (Adaptive Cruise Control) function.

The ACC function is a follow-up driving function that causes the vehicle 1 to follow a preceding vehicle, which is another vehicle ahead of the vehicle 1. For example, the steering wheel is provided with an operation switch related to the ACC function. The operation switches include an ACC switch 11 that is turned on/off to enable/disable the ACC function, a set switch that sets the current vehicle speed of vehicle 1 as the set vehicle speed, and a switch that controls the distance between vehicle 1 and the preceding vehicle. This includes a set vehicle distance changeover switch that switches between vehicles, a cancel switch that deactivates the ACC function, and a resume switch that reactivates the ACC function at the previously set vehicle speed.

When the ACC switch 11 is pressed and turned on, the ACC function becomes effective. Thereafter, when the set switch is pressed, the current vehicle speed of the vehicle 1 is set to the set vehicle speed. The set vehicle speed can be changed by pressing a resume switch or a set switch. That is, by pressing the resume switch, the set vehicle speed can be increased, and by pressing the set switch, the set vehicle speed can be decreased. Further, by pressing the set inter-vehicle distance changeover switch, for example, it is possible to switch between setting the inter-vehicle distance to a longer distance, a shorter distance, or an intermediate value.

When the set vehicle speed is set, the ECU 5 starts ACC control (following travel control) that causes the vehicle 1 to travel while following the preceding vehicle in front of it. In ACC control, depending on the presence or absence of a preceding vehicle, there is a following driving mode in which the vehicle follows the preceding vehicle with the set vehicle speed set by a switch operation as the upper limit vehicle speed, and a constant speed driving mode in which the vehicle travels at a constant speed at the set vehicle speed. is automatically switched. In the following driving mode, the vehicle 1 is accelerated or decelerated so that the distance between the vehicle 1 and the preceding vehicle ahead of the vehicle 1 is maintained at the target distance. Specifically, a target inter-vehicle distance between vehicle 1 and the preceding vehicle is set based on the vehicle speed of vehicle 1, and the inter-vehicle distance deviation between the target inter-vehicle distance and the actual inter-vehicle distance (=actual inter-vehicle distance - target inter-vehicle distance) is required. Additionally, the relative speed between the vehicle 1 and the preceding vehicle is determined. Then, a target acceleration of the vehicle 1 is set according to the inter-vehicle distance deviation and relative speed, and the output of the engine 2 or the braking force of the hydraulic brake is controlled so that the vehicle 1 accelerates or decelerates at the target acceleration.

<ACC control processing>
2A and 2B are flowcharts showing the flow of ACC control processing.

While the ignition switch of the vehicle 1 is on, the ECU 5 executes the ACC control process.

In the ACC control process, first, it is determined whether the ACC switch 11 is turned on (step S11). While the ACC switch 11 is off, the ACC control process does not proceed further.

When the ACC switch 11 is turned on (YES in step S11), the ACC function is enabled. Then, when the set vehicle speed is set by pressing the set switch or the resume switch, ACC control is started (step S12).

When the ACC control is started, it is then determined whether or not there is a preceding vehicle to be followed in front of the vehicle 1 (step S13). If there is a vehicle traveling in the same direction on the same course (lane) as the vehicle 1 within a predetermined distance range in front of the vehicle 1, that vehicle is determined to be the preceding vehicle to be followed.

If there is a preceding vehicle to be followed (YES in step S13), a following driving mode is set (step S14). In the following driving mode, as described above, the vehicle 1 is accelerated or decelerated so that the inter-vehicle distance between the vehicle 1 and the preceding vehicle in front of it is maintained at the target inter-vehicle distance.

In the following driving mode, it is determined whether the preceding vehicle has stopped (step S15). If the preceding vehicle is not stopped (NO in step S15), it is determined to continue driving to follow the preceding vehicle (step S16), and whether or not there is still a preceding vehicle to be followed in front of the vehicle 1 is determined. is determined (step S13).

If there is no preceding vehicle to be followed (NO in step S13), constant speed driving mode is set (step S17). In the constant speed driving mode, the output of the engine 2 is controlled so that the vehicle 1 runs at a set vehicle speed set by a switch operation, and the brake actuator 4 is also controlled as necessary.

In the follow-up driving mode, when the preceding vehicle has stopped (YES in step S15), the vehicle 1 is stopped at a position with an inter-vehicle distance from the preceding vehicle according to the setting made by pressing the set inter-vehicle distance changeover switch. (Step S18). Furthermore, when the vehicle is stopped, if the IDS control stop conditions are met, the engine 2 is stopped (idling stop). The stop condition is a condition in which it is determined that the power of the engine 2 is unnecessary because the vehicle 1 is heading to a stop, and the condition includes, for example, a brake condition in which the brake operation continues for a certain period of time or more. and a vehicle speed condition that the vehicle speed is less than or equal to an IDS starting vehicle speed (for example, 10 km/h) that is greater than 0 km/h.

After the vehicle 1 has stopped, it is determined whether an accelerator operation, which is an operation of an accelerator pedal, has been performed (step S19 in FIG. 2B).

If the accelerator is not operated (NO in step S19), it is determined whether the preceding vehicle has started (step S20). If the preceding vehicle has not started but is stopped (NO in step S20), it is determined again whether an accelerator operation has been performed (step S19).

If there is an accelerator operation (YES in step S19), the accelerator operation is treated as a control restart request operation, and control restart request operation information is stored in the volatile memory of the ECU 5 (step S21).

When the accelerator operation is treated as a control restart request operation, no control is performed to accelerate the vehicle 1 in response to the accelerator operation, and the driving force for driving the vehicle 1 is suppressed (step S22). By suppressing the driving force, the vehicle 1 remains stationary without moving. The method of suppressing the driving force is not particularly limited, and may include prohibition of starting the stopped engine 2 through IDS control, suppression of the output of the engine 2, brake operation using a hydraulic brake, or a clutch for switching the vehicle 1 between forward and backward movement. It may be control such as opening or slipping, or a combination of these controls.

Thereafter, it is determined whether the preceding vehicle has started within a predetermined time after the control restart request operation information is stored in the nonvolatile memory (step S23).

If the preceding vehicle starts moving within a predetermined time after the control restart request operation information is stored (YES in step S23), the user (driver) is notified of the preceding vehicle's starting, for example, by voice or the like (step S24). . Then, the suppression of the driving force for driving the vehicle 1 is released (step S25), the ACC control in the following driving mode is restarted, and the driving of the vehicle 1 following the preceding vehicle is resumed (step S26). . After the vehicle 1 resumes following, the control restart request operation information is cleared (erased) from the nonvolatile memory (step S27), and it is determined again whether the preceding vehicle has stopped (step S15 in FIG. 2A). ).

If the preceding vehicle does not start within a predetermined time from the storage of the control restart request operation information (NO in step S23 in FIG. 2B), the stopped state continues to be maintained by suppressing the driving force for driving the vehicle 1. (Step S28). In this case, the control restart request operation information is cleared from the nonvolatile memory (step S29), and it is determined again whether an accelerator operation has been performed (step S19).

On the other hand, if the preceding vehicle starts without an accelerator operation being performed (YES in step S20), the user is notified of the starting of the preceding vehicle (step S30). If the driving force for driving the vehicle 1 is suppressed, the suppression is canceled (step S31), and ACC control in constant speed driving mode is started (step S32). Thereafter, it is determined again whether a preceding vehicle to be followed still exists in front of the vehicle 1 (step S13 in FIG. 2A).

<ACC termination process>
FIG. 3 is a flowchart showing the flow of ACC termination processing.

While the ACC switch 11 is on, the ECU 5 executes ACC termination processing.

In the ACC termination process, it is determined whether the ACC switch 11 is turned off (step S41). While the ACC switch 11 is on, the ACC termination process does not proceed further.

When the ACC switch 11 is turned off (step S42), the ACC function is disabled. If the ACC control is being executed due to the invalidation of the ACC function, the execution of the ACC control is forcibly canceled (step S42). This ends the ACC termination process.

<Effect>
As described above, when the ACC function is enabled and there is a preceding vehicle to be followed in front of the vehicle 1, the ACC control in the following driving mode in which the vehicle 1 follows the preceding vehicle ahead of the vehicle 1 is performed. executed. If the ACC function is enabled and the accelerator is operated while vehicle 1 and the preceding vehicle are stopped, the accelerator operation is processed as a control restart request operation, and the driving force for vehicle 1 to travel is suppressed. be done. If the accelerator operation is processed as a control restart request operation, the suppression of the driving force is canceled in response to the start of the preceding vehicle, and execution of the ACC control is resumed. As a result, the vehicle 1 starts following the preceding vehicle.

In a configuration where the ACC control is restarted in response to the start of the preceding vehicle when the start/stop switch provided near the steering wheel is turned on, the relationship between the start of the vehicle 1 and the operation of the start/stop switch is Since the function of the start/stop switch is difficult for the user to remember, the function of restarting the ACC control in response to the start of the preceding vehicle may not be utilized. On the other hand, in a configuration in which the ACC control is restarted in response to the start of the preceding vehicle when the accelerator operation is performed, the user may perform the accelerator operation when the vehicle 1 starts in response to the start of the preceding vehicle. It is intuitively understood and easy to remember as an operation that requests restart of ACC control. Therefore, it is possible to improve the degree of utilization of the function in which the ACC control is restarted in response to the start of the preceding vehicle.

Further, when the accelerator operation is processed as a control restart request operation, the driving force for driving the vehicle 1 is suppressed, so that the movement of the vehicle 1 in response to the accelerator operation can be suppressed, and the vehicle 1 This can prevent collisions with vehicles in front.

Moreover, since the user does not need to move his or her line of sight to operate the accelerator, it is possible to prevent the user's attention from straying from the front.

In addition, if the ACC function is enabled and the vehicle 1 and the preceding vehicle are stopped and the vehicle in front starts moving without any accelerator operation being performed, the distance between vehicle 1 and the preceding vehicle is such that the vehicle 1 and the preceding vehicle are no longer being tracked in the following mode. When the value exceeds a predetermined value, ACC control is executed in a constant speed driving mode in which the vehicle 1 is caused to travel at a constant speed at a set vehicle speed. Therefore, even if the user forgets to operate the accelerator to request resumption of ACC control in response to the start of the preceding vehicle, vehicle 1 will start when the preceding vehicle starts, so vehicle 1 will not stop. You can prevent it from continuing.

<Modified example>
Although one embodiment of the present invention has been described above, the present invention can also be implemented in other forms.

For example, in the above-described embodiment, the set vehicle speed is set by pressing the set switch and the resume switch. , a speed limit sign (maximum speed sign) may be recognized from the image taken by the camera, and the speed displayed on the speed limit sign may be set as the set speed.

Further, in the above-described embodiment, the engine control logic, the shift control logic, and the brake control logic are incorporated in the ECU 5, but for example, the engine ECU that controls the engine 2, the transmission ECU that controls the transmission 3, A brake ECU that controls the brake actuator 4 may be provided separately, and the functions of the ECU 5 may be realized by cooperation of the engine ECU, transmission ECU, and brake ECU, and the ECU used to realize the functions of the ECU 5. There is no restriction on the number of

Further, in the above-described embodiment, the case where the tracking cruise control device according to the present invention is applied to the conventional vehicle 1 using the engine 2 as the drive source is discussed, but the tracking cruise control device according to the present invention uses the motor as the drive source. It can also be applied to a vehicle equipped as a drive source for running, that is, an electric vehicle such as an electric vehicle (EV) or a hybrid vehicle (HV).

Furthermore, the accelerator operation is not limited to a foot operation of an accelerator pedal, but may be a manual operation of an accelerator grip, an accelerator lever, or the like.

In addition, various design changes can be made to the above-described configuration within the scope of the claims.

1: Vehicle 5: ECU (follow-up travel control device, follow-up travel control execution means, driving force suppression means, control restart means, constant speed travel control execution means)
6: Accelerator sensor (accelerator operation detection means)

Claims (1)

memory and
an accelerator operation detection means for detecting an accelerator operation;
When a following driving function is enabled and there is a preceding vehicle to be followed in front of the own vehicle, a following driving control execution means executes following driving control for causing the own vehicle to follow the preceding vehicle. ,
When the following driving function is enabled and the accelerator operation is detected by the accelerator operation detection means while the own vehicle and the preceding vehicle are stopped, the accelerator operation is treated as a control restart request operation and the control is performed. a driving force suppressing means for storing restart request operation information in the memory and suppressing a driving force for driving the own vehicle;
When the control restart request operation information is stored in the memory, in response to the start of the preceding vehicle, the suppression of the driving force by the driving force suppressing means is canceled, and the following driving control is executed by the following driving control execution means. control restart means for resuming execution of the
When the following driving function is enabled and the preceding vehicle starts without the accelerator operation being detected by the accelerator operation detection means while the own vehicle and the preceding vehicle are stopped, the own vehicle is set. A follow-up cruise control device , comprising: constant-speed cruise control execution means for executing constant-speed cruise control to cause the vehicle to travel at a constant speed .

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