JP2014141115A - Vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately execute a turning performance improvement control and a drive force control corresponding to a driver's acceleration/deceleration request without giving a driver discomfort even if an acceleration/deceleration request operation is performed in a state of limiting the drive force control.SOLUTION: A vehicle control device capable of executing a turning performance improvement control for controlling a drive force of a vehicle to stabilize a vehicle behavior during turning traveling, includes drive-force correction means (Steps S4 to S6) for controlling the drive force by applying a change amount of the drive force corresponding to a change request operation to an actual drive force of the vehicle at a time of performing the change request operation if a driver performs the change request operation for changing the drive force to an opposite direction to a direction of changing the drive force under the drive force control while execution of the drive force control is limited in the turning performance improvement control.

Description

  The present invention relates to a vehicle capable of executing a turning performance improvement control for controlling a driving force and a braking force of a vehicle during turning, thereby improving the turning performance of the vehicle and stabilizing vehicle behavior during turning. The present invention relates to a control device.

  Developed technology related to turning performance control that stabilizes the behavior and posture of a vehicle while turning by automatically controlling the driving force and braking force of the vehicle along with the steering operation by the driver when turning the vehicle. Has been. As an example, Patent Document 1 describes an invention relating to a vehicle stabilization control system that controls a driving force so that a vehicle stability factor follows a target value. In the invention described in Patent Document 1, a physical quantity for generating a basic required driving force required by a driver at a driving wheel of a vehicle is calculated during turning, and is applied to each of a front wheel and a rear wheel of the vehicle. A stability factor target value is calculated based on the detection result of the applied load and the estimation result of the virtual turning radius of the vehicle. Then, the physical quantity corresponding to the basic required driving force is corrected so that the actual stability factor of the vehicle follows the target value, and the driving force corresponding to the corrected physical quantity is generated on the driving wheels. ing.

  Patent Document 2 discloses a braking force control device that performs deceleration control when a vehicle is turning, and based on the driver's accelerator operation, the driver's intention to accelerate the vehicle is accelerated by the accelerator operation. Calculates the acceleration intention realization drive torque to be realized and the braking torque that the deceleration control at the time of turning is generated, and the vehicle is generated based on the subtraction result obtained by subtracting the braking torque from the calculated acceleration intention realization drive torque An invention relating to a braking force control device configured to vary the driving torque is described. Furthermore, this patent document 2 describes that the acceleration intention realizing driving torque is increased as the accelerator operation amount of the driver is increased.

JP 2005-256636 A JP 2008-18777 A

  As described above, in the invention described in Patent Document 1, the driving force of the vehicle is controlled so that the stability factor of the vehicle becomes the target stability factor. That is, so-called turning performance improvement control is executed. The driving force in the turning performance improvement control is automatically controlled based on the running state and behavior of the vehicle, separately from the required driving force based on the driver's accelerator operation and brake operation. For example, when the vehicle turns, the target yaw rate of the vehicle is obtained based on values such as the vehicle speed and the steering angle, and the vehicle driving force and control are adjusted so that the actual yaw rate of the vehicle approaches the target yaw rate. Power is automatically controlled. By executing such turning improvement control, the vehicle behavior during turning can be stabilized, and the turning performance of the vehicle can be improved.

  On the other hand, in the turning performance improvement control that automatically controls the driving force separately from the driver's intention as described above, the driving force control in the turning performance improvement control should be realized originally due to restrictions on the structure of the vehicle and the system. The amount of change in driving force may not be changed. For example, when the driving force is reduced by driving force control, the engine output torque cannot be reduced below the lower limit torque when the throttle opening is fully closed. Alternatively, if the vehicle is a hybrid vehicle, the amount of decrease in driving force may be limited by the regeneration limit of the motor. Under such circumstances, if the driver performs an acceleration / deceleration request operation such as an accelerator operation or a brake operation, the target value for driving force control is limited by the lower limit torque or the regeneration limit as described above. Until the vehicle is off, the driving force of the vehicle may not change despite the driver's acceleration / deceleration request.

  Specifically, as shown in the time chart of FIG. 10, when the turning performance improvement control is started at time t1, the driving force of the vehicle, that is, the vehicle torque, is commanded by the driving force control in the turning performance improvement control. Decreases according to torque. However, the actual vehicle torque is limited to a lower value by the vehicle torque limit value inevitably determined by the lower limit torque or the regeneration limit as described above. That is, the vehicle torque that should be reduced by the driving force control is limited by the limit value, and the control request torque that is reduced in the turning performance improvement control cannot be satisfied. Then, when the accelerator is turned on by the driver's acceleration request operation at time t2 in this state, the control torque increases in accordance with the increase in the accelerator opening, but the actual vehicle torque exceeds the limit value. Will not increase. Therefore, from the time the accelerator is turned on at time t2 until the control torque exceeds the limit value, the vehicle does not accelerate without increasing the driving force even though the driver depresses the accelerator pedal. Become. As a result, the driver may feel uncomfortable.

  The above example shows the problem of the prior art in the case where the driving force is reduced by the driving force control in the turning performance improvement control, and the change in the driving force reduction direction is limited by the restrictions of the vehicle. However, a similar event can also occur when the driving force is increased by the driving force control in the turning performance improvement control, and the change in the increasing direction of the driving force is limited by the constraints of the vehicle. That is, when the driving force control for increasing the driving force by the turning performance improvement control is being executed, an increase in the driving force is restricted, and for example, the driver performs a deceleration requesting operation such as returning the accelerator pedal that was depressed. If this is done, the driver may not be decelerated because the driving force does not decrease even though the accelerator is returned. As a result, the driver may feel uncomfortable or uneasy.

  As described above, in the conventional turning performance improvement control, the driving force control in the turning performance improvement control is limited by the vehicle structure or the system restrictions, and the driver's operation such as an accelerator operation or a brake operation is applied. To appropriately execute both the driving force control in the turning performance improvement control and the driving force control corresponding to the driver's acceleration / deceleration control without giving the driver a sense of incompatibility when the deceleration request operation is performed. There was still room for improvement.

  The present invention has been made paying attention to the technical problem described above, and when an acceleration / deceleration request operation is performed by the driver in a state where the driving force control in the turning performance improvement control is limited by the restrictions of the vehicle. Even so, the vehicle control device can appropriately execute both the driving force control in the turning performance improvement control and the driving force control corresponding to the driver's acceleration / deceleration request without giving the driver a sense of incongruity. Is intended to provide.

  In order to achieve the above object, the invention of claim 1 is directed to a vehicle control device capable of executing a turning improvement control for controlling a driving force of a vehicle to stabilize a vehicle behavior during turning, wherein the turning ability is performed. When the driving force change request operation by the driver in the direction opposite to the driving force change direction by the driving force control is performed when the execution of the driving force control in the improvement control is restricted, the change Driving force correction means is provided for controlling the driving force by giving the amount of change in the driving force corresponding to the requested operation to the actual driving force of the vehicle at the time when the requested change operation is performed. Is a control device characterized by

  Further, the invention of claim 2 is the driving of the driver in the invention of claim 1, when the change request operation is performed, using at least one of the operation amount and the operation speed of the change request operation as an index. The driving force correcting unit further includes an estimating unit that estimates the magnitude of the force change request, and the driving force correcting unit corrects the required driving force corresponding to the change request operation in a normal time when the driving force control is not executed. As an upper limit, the control device includes means for increasing the amount of change applied to the actual driving force as the estimated driving force change request increases.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the driving force correction means allows the driver to experience a change in the driving force by applying the change amount. The control device includes means for setting a lower limit of the change amount.

  The invention according to claim 4 includes means for setting the amount of change to 0 when the estimated magnitude of the driving force change request is smaller than a predetermined value in the invention of claim 2 or 3. Is a control device characterized by

  According to the first aspect of the present invention, when the vehicle is turning, the turning performance improvement control for automatically controlling the driving force of the vehicle and stabilizing the vehicle behavior during the turning is executed. Then, during the execution of the driving force control in the turning performance improvement control, in the situation where the execution of the driving force control is restricted due to the constraints on the configuration of the vehicle, the change direction of the driving force by the driving force control When an operation requesting a change in driving force by the driver in the reverse direction is performed, that is, in a situation where a decrease in the driving force is restricted by the driving force control in the turning performance improvement control, the driver's acceleration request operation is performed. Or when the driver requests a deceleration request while the increase in the driving force is restricted by the driving force control in the turning performance improvement control, the acceleration request operation or the deceleration request operation is performed. The driving force of the vehicle is controlled by applying a change amount of the driving force corresponding to the acceleration requesting operation or the deceleration requesting operation to the actual driving force at that time. Therefore, even if the change in driving force is restricted due to restrictions on the structure of the vehicle and the system, when the driver performs an acceleration / deceleration request operation, the vehicle is operated regardless of the driver's operation. It is possible to avoid the occurrence of a phenomenon that the driving force of the vehicle does not change and to realize the change of the driving force intended by the driver. Therefore, both the driving force control in the turning performance improvement control and the driving force control corresponding to the driver's acceleration / deceleration request can be appropriately executed without causing the driver to feel uncomfortable.

  The driving force automatically controlled in the turning performance improvement control of the present invention includes a positive driving force for driving the vehicle and a negative driving force for braking the vehicle, that is, a braking force. For example, when the driving force is changed by the control amount in the positive direction, the output of the driving force source of the vehicle is increased. Alternatively, when the braking force has already been generated, the braking force is reduced. On the other hand, when the driving force is changed by a negative control amount, the output of the driving force source of the vehicle is reduced. Alternatively, a braking force is applied to the vehicle. Alternatively, if a braking force has already been generated, the braking force is increased.

  According to the invention of claim 2, during the execution of the driving force control in the turning performance improvement control, the driving force change request operation is performed by the driver in the direction opposite to the driving force changing direction by the driving force control. In such a case, the magnitude of the driving force change request of the driver is estimated based on the driving force change request operation by the driver. For example, it is estimated that the driving force change request is larger as the operation amount of the driving force change request operation is larger. Alternatively, it is estimated that the driving force change request is larger as the operation speed of the driving force change request operation is higher. Alternatively, it is estimated that the driving force change request is larger as the operation amount of the driving force change request operation is larger and the operation speed is faster. Then, the larger the estimated driving force change request of the driver is, the larger the amount of change in driving force corresponding to the driver's change request operation is controlled. In this case, the change amount of the driving force is set so as not to exceed the change amount (normal change amount) of the driving force corresponding to the change request operation at the normal time. Therefore, when the driving force is controlled based on the driving force change request operation by the driver during the driving force control in the turning performance improvement control as described above, the driving intention is well reflected. The power can be controlled. Furthermore, since the amount of change in the driving force in that case is set so as not to exceed the normal amount of change, excessive acceleration / deceleration due to the control of the driving force with the amount of change beyond the driver's intention. Can be prevented.

  According to the invention of claim 3, when the driving force of the vehicle is limited by applying the change amount of the driving force to the actual driving force as described above, at least the driver can experience the change of the driving force. A lower limit is set for the amount of change. Therefore, even when the driving force is controlled in response to the driver's change request operation when the turning performance improvement control is executed, it is possible to ensure the amount of change in the driving force that the driver can feel a change. it can.

  According to the invention of claim 4, during the execution of the driving force control in the turning performance improvement control, the driving force change request operation by the driver in the direction opposite to the driving force changing direction by the driving force control is performed. In such a case, the magnitude of the driving force change request of the driver is estimated based on the driving force change request operation by the driver. If the estimated driving force change request of the driver is smaller than a predetermined value set as a threshold value, the amount of change in driving force in the driving force control corresponding to the driver's change request operation is zero. Is done. That is, when the estimated driver driving force change request is smaller than a predetermined value, the driving force is not changed. Therefore, when the driver's request for change in driving force or the willingness of acceleration / deceleration is small, a change in driving force unintended by the driver due to a slight swing of the accelerator pedal can be suppressed.

It is a schematic diagram showing an example of a configuration of a vehicle and a control system to be controlled in the present invention. It is a figure for demonstrating an example of the turning performance improvement control by the control apparatus of this invention, Comprising: The acceleration / deceleration request | requirement operation by a driver | operator is performed in the condition where the variation | change_quantity of the driving force control in turning performance improvement control is restrict | limited. It is a flowchart for demonstrating the example of the corresponding | compatible control in case of a failure. FIG. 3 is a diagram for explaining an example of response control in the turning performance improvement control of the present invention shown in FIG. 2, and is a time chart for explaining behavior of control torque and vehicle torque when the response control is executed. . FIG. 4 is a time chart for explaining an improvement when the corresponding control in the turning performance improvement control of the present invention shown in FIGS. 2 and 3 is executed. It is a figure for demonstrating an example of the turning performance improvement control by the control apparatus of this invention, Comprising: The acceleration / deceleration request | requirement operation by a driver | operator is performed in the condition where the variation | change_quantity of the driving force control in turning performance improvement control is restrict | limited. 12 is a flowchart for explaining another example of response control in the case of failure. FIG. 6 is a diagram for explaining an example of response control in the turning performance improvement control of the present invention shown in FIG. 5, and is a time chart for explaining the behavior of control torque and vehicle torque when the response control is executed. . FIG. 6 is a diagram for explaining an example of response control in the turning performance improvement control of the present invention shown in FIG. 5, and is a time chart for explaining the behavior of control torque and vehicle torque when the response control is executed. . FIG. 6 is a diagram for explaining an example of response control in the turning performance improvement control of the present invention shown in FIG. 5, and is a time chart for explaining the behavior of control torque and vehicle torque when the response control is executed. . FIG. 6 is a diagram for explaining an example of response control in the turning performance improvement control of the present invention shown in FIG. 5, and is a time chart for explaining the behavior of control torque and vehicle torque when the response control is executed. . The behavior of the control torque and the vehicle torque when the driver performs an acceleration / deceleration request operation in a situation where the amount of change in the driving force control in the turning performance improvement control is limited in the conventional turning performance improvement control will be described. It is a time chart for.

  Next, an embodiment of the present invention will be described with reference to the drawings. First, the configuration and control system of a vehicle to be controlled in the present invention will be described with reference to FIG. The vehicle targeted by the present invention controls the driving force and braking force of the vehicle independently of driving operations such as accelerator operation and braking operation by the driver, that is, driving of the vehicle based on the driving operation by the driver. Apart from the control of the force and the braking force, the driving force and the braking force can be automatically controlled. The vehicle Ve shown in FIG. 1 has left and right front wheels 1 and 2 and left and right rear wheels 3 and 4. In the example shown in FIG. 1, the vehicle Ve is configured as a rear-wheel drive vehicle that drives the rear wheels 3 and 4 by the power output from the driving force source 5.

  As the driving force source 5, for example, at least one of an internal combustion engine and an electric motor can be used. Alternatively, both the internal combustion engine and the electric motor can be mounted as the driving force source 5 as a hybrid vehicle. When an internal combustion engine such as a gasoline engine, a diesel engine, or a natural gas engine is mounted on the vehicle Ve as the driving force source 5, various transmissions such as a manual transmission and an automatic transmission are provided on the output side of the driving force source 5 ( (Not shown) is used. When an electric motor is mounted on the vehicle Ve as the driving force source 5, a power storage device (not shown) such as a battery or a capacitor is connected to the electric motor via an inverter, for example.

  An electronic control unit (ECU) 6 for controlling the output state of the driving force source 5 to control the driving state of the rear wheels 3 and 4 is provided. That is, the electronic control unit 6 is connected to the driving force source 5 and the electronic control unit 6 controls the output of the driving force source 5 to generate the rear wheels 3 and 4, that is, the driving wheels 3 and 4. The driving force of the vehicle Ve can be automatically controlled.

  In addition, each of the wheels 1, 2, 3, and 4 is equipped with brake devices 7, 8, 9, and 10, respectively. Each of the brake devices 7, 8, 9, 10 is connected to the electronic control device 6 via the brake actuator 11. Therefore, the braking force of the vehicle Ve generated by each wheel 1, 2, 3, 4 by controlling the brake actuator 11 by the electronic control device 6 and controlling the operation state of each brake device 7, 8, 9, 10 is achieved. It is the structure which can be automatically controlled individually.

  On the other hand, the electronic control device 6 is configured to receive detection signals from various sensors of each part of the vehicle Ve and information signals from various in-vehicle devices. For example, an accelerator sensor 12 that detects an accelerator depression angle (or depression amount or accelerator opening), a brake sensor 13 that detects a brake depression angle (or depression amount or brake opening), and a steering angle of a steering wheel are detected. Steering angle sensor 14, wheel speed sensor 15 for detecting the rotational speed (wheel speed) of each drive wheel 1, 2, 3, 4 respectively, acceleration in the longitudinal direction (vertical direction in FIG. 1) of vehicle Ve (ie, longitudinal acceleration) ), A lateral acceleration sensor 17 that detects acceleration (ie, lateral acceleration) in the direction of the axle of the vehicle Ve (ie, lateral acceleration in FIG. 1), a yaw rate sensor 18 that detects the yaw rate of the vehicle Ve, or a drive. A detection signal from a torque sensor (not shown) for detecting the output torque of the force source 5 is electronically controlled. It is configured to be input to the device 6.

  With the configuration as described above, the vehicle Ve can control the steering characteristics and the stability factor. In particular, the vehicle Ve in the present invention is configured to improve the steering characteristics during turning while improving the turning performance of the vehicle Ve. For example, the vehicle speed and the friction coefficient of the road surface are estimated from the wheel speeds of the respective wheels 1, 2, 3, and 4 detected by the wheel speed sensor 15, the vehicle speed, the road surface friction coefficient, the steering angle detected by the steering angle sensor 14, and the like. Based on this, it is possible to set a target steering characteristic that is a target of the vehicle Ve, and to control the actual steering characteristic of the vehicle Ve to follow the target steering characteristic.

  Specifically, the actual steering characteristic of the vehicle Ve is changed to the target steering characteristic by controlling the yaw rate of the vehicle Ve by changing the driving force and the braking force of the vehicle Ve, that is, performing so-called turning improvement control. You can get closer. When controlling the yaw rate of the vehicle Ve, the target yaw rate of the vehicle Ve at that time is obtained based on information such as the vehicle speed, the steering angle, and the wheel base. Then, by performing the above-described turning performance improvement control, the yaw rate of the vehicle Ve can be controlled so that the actual yaw rate of the vehicle Ve approaches the target yaw rate. For example, by increasing or decreasing the correction torque with respect to the driving torque applied to the driving wheels 3, 4 or the braking torque applied to the wheels 1, 2, 3, 4, the vehicle Ve The yaw rate can be controlled.

  As described above, a control technique for setting the target yaw rate and causing the actual yaw rate of the vehicle Ve to follow the target yaw rate is described in, for example, Japanese Patent Laid-Open No. 5-278488. Further, as described above, Japanese Patent Laying-Open No. 2005-256636 (Patent Document 1) describes a control technique for controlling the driving force of driving wheels so that the vehicle stability factor follows a target value. As described above, the basic control contents of the turning performance improvement control that stabilizes the behavior and posture of the vehicle during turning by automatically controlling the driving force of the vehicle are well known by each of the above-mentioned patent documents. A more specific description is omitted here.

  As described above, in the conventional turning performance improvement control, when the driver performs an acceleration / deceleration request operation in a state where the driving force control in the turning performance improvement control is limited by the constraints of the vehicle, There is a possibility that the driver feels uncomfortable because the driving force does not change against the intention. Therefore, in the vehicle control device according to the present invention, when an acceleration / deceleration request operation is performed by the driver while the driving force control in the turning performance improvement control is limited as described above, the acceleration / deceleration request is performed. The driving force of the vehicle Ve is controlled by the driving force control corresponding to the operation. Specifically, the change corresponding to the acceleration / deceleration request operation is based on the actual driving force of the vehicle Ve at the time of execution of the acceleration / deceleration request operation. It is comprised so that driving force of this may be provided.

  FIG. 2 is a flowchart for explaining an example of the control, and the routine shown in this flowchart is repeatedly executed every predetermined short time. In FIG. 2, it is first determined whether or not the driving force control in the turning performance improvement control is being executed (step S1). As described above, the problem to be solved by the present invention is that the driving force is controlled by the driver in a state where the reduction of the driving force is limited during the execution of the control for reducing the driving force by the driving force control in the turning performance improvement control. When the acceleration request operation is performed, and when the increase in the driving force is restricted during the execution of the control for increasing the driving force by the driving force control in the turning performance improvement control, the deceleration request operation by the driver is performed. It can happen both when done. Therefore, in step S1, whether or not the control for reducing the driving force by the driving force control in the turning performance improvement control is being executed, or the control for increasing the driving force by the driving force control in the turning performance improvement control is executed. It is determined whether it is in the middle. However, in the following description, for the sake of convenience, a case where an acceleration requesting operation is performed by the driver during the execution of the control for reducing the driving force by the driving force control in the one turning performance improvement control will be described as an example.

  If the driving force control in the turning performance improvement control is not being executed and if a negative determination is made in step S1, this routine is temporarily terminated without executing the subsequent control. On the other hand, when the driving force control in the turning performance improvement control is being executed, if the determination in step S1 is affirmative, the process proceeds to step S2. Then, it is determined whether or not the driver has operated the accelerator. That is, in this step S2, whether or not there has been a change in the depression amount or depression angle of the accelerator pedal by the driver based on the detection value of the accelerator sensor 13, specifically, whether or not an operation of depressing the accelerator pedal has been performed. Is judged.

  If a negative determination is made in step S2 because the driver does not operate the accelerator, that is, the accelerator pedal is not depressed, this routine is temporarily executed without executing the subsequent control. finish. On the other hand, if it is determined affirmative in step S2 that the driver has operated the accelerator, that is, that the accelerator pedal has been depressed, the process proceeds to step S3. Then, the vehicle torque limit value grd_trq is read. As described above, this limit value grd_trq is a value that is inevitably determined by the lower limit torque of the engine or the regeneration limit of the motor, and is the lower limit when the driving force, that is, the vehicle torque is reduced by the turning performance improvement control, or the vehicle This is the upper limit for increasing the torque.

  Subsequently, it is determined whether or not the control torque crt_trq is smaller than the limit value grd_trq (step S4). As described above, the control torque crt_trq is a control command value for the vehicle torque output by the driving force control in the turning performance improvement control.

  If the control torque crt_trq is greater than or equal to the limit value grd_trq and if a negative determination is made in step S4, this routine is temporarily terminated without executing the subsequent control. On the other hand, if the control torque crt_trq is smaller than the limit torque grd_trq and the determination is affirmative in step S4, the process proceeds to step S5. Then, the required torque change amount drvreq_trq is obtained. This required torque change amount drvreq_trq indicates the change amount of torque to be changed by the driving force control corresponding to the driver's acceleration request operation. Accordingly, in step S5, the required torque change amount drvreq_trq is obtained based on the detection value of the accelerator sensor 13.

When the required torque change amount drvreq_trq is obtained in step S5, the driving force of the vehicle Ve is controlled based on the required torque change amount drvreq_trq. That is, the driving force of the vehicle Ve is controlled by driving force control corresponding to the driver's acceleration request operation (step S6). Specifically, assuming that the actual vehicle torque at the current time is act_trq, the control request torque req_trq output as a control command value for the engine 5 is:
req_trq = act_trq + drvreq_trq
It is calculated by the following equation. Then, the output of the engine 5 is controlled based on the calculated control request torque req_trq. In short, in this case, based on the actual vehicle torque act_trq at the time when the driver's acceleration request operation is executed, the required torque change amount drvreq_trq corresponding to the change corresponding to the driver's acceleration request operation is added to the vehicle torque act_trq. By doing so, the driving force of the vehicle Ve is controlled. Thereafter, this routine is once terminated.

  The behavior of the vehicle torque act_trq when controlled as described above is shown in the time chart of FIG. When it is determined at time t11 that the turning performance improvement control is started, that is, when an execution command for turning performance improvement control is output, the control torque ctr_trq commanded by the driving force control in this turning performance improvement control decreases. Accordingly, the actual vehicle torque act_trq decreases. However, the vehicle torque act_trq is limited to a lower value by the vehicle torque limit value grd_trq that is inevitably determined by the lower limit torque of the engine or the regeneration limit of the motor as described above. Then, when the accelerator is turned on by the driver's acceleration request operation at time t12 in this state, the control torque ctr_trq increases as the accelerator opening increases. In the present invention, the vehicle torque act_trq is It is not controlled based on the control torque ctr_trq, but is controlled according to the required torque change amount drvreq_trq determined according to the accelerator opening. That is, the required torque change amount drvreq_trq is applied to the actual vehicle torque act_trq at the time when the driver requests acceleration request operation (time t12), whereby the vehicle torque act_trq, that is, the driving force of the vehicle Ve is controlled.

  By controlling the driving force of the vehicle Ve as described above, an acceleration / deceleration requesting operation by the driver is performed even in a situation where the change in the driving force is restricted due to restrictions on the structure or system of the vehicle Ve. In such a case, it is possible to avoid the occurrence of a phenomenon in which the driving force of the vehicle Ve does not change despite the driver's operation, and to realize a change in the driving force intended by the driver.

  By the way, although the driving force control reflecting the driver's intention can be performed by controlling the driving force of the vehicle Ve as described above, the control effect expected for the original turning performance improvement control is achieved. It may not be obtained. Specifically, as shown in the time chart of FIG. 4, when the driver's required driving force corresponding to a change in the accelerator opening caused by the driver's acceleration / deceleration request operation, that is, the required torque is drv_trq, the vehicle as described above When the Ve driving force is controlled, the amount of change in the driving force is the amount of change in the driving force that is actually changed while the amount of change in the driving force that is desired to be realized by the original turning control is the amount of change d1. Becomes a change amount d2 smaller than the change amount d1. Therefore, the intended control effect in the original turning improvement control cannot be obtained.

  Therefore, in the present invention, when the driver's acceleration / deceleration request operation is performed in a situation where the driving force control in the turning performance improvement control is limited as described above, the driver is based on the driver's acceleration / deceleration request operation. It is also possible to estimate the acceleration / deceleration will and to change the amount of change in the driving force in accordance with the magnitude of the acceleration / deceleration will.

  FIG. 5 is a flowchart for explaining an example of the control, and the routine shown in this flowchart is repeatedly executed every predetermined short time. In FIG. 5, it is first determined whether or not the driving force control in the turning performance improvement control is being executed (step S11). In the control example shown in the flowchart of FIG. 5 as well, as in the control example shown in the flowchart of FIG. 2 described above, for the sake of convenience, the driver is performing the control for reducing the driving force by the driving force control in the turning performance improvement control. An example in which an acceleration request operation is performed will be described.

  If the driving force control in the turning performance improvement control is not being executed and if a negative determination is made in this step S11, this routine is temporarily ended without executing the subsequent control. On the other hand, if the driving force control in the turning performance improvement control is being executed and if a positive determination is made in step S11, the process proceeds to step S12. Then, it is determined whether or not the driver has operated the accelerator. That is, in this step S12, it is determined whether or not an operation for depressing the accelerator pedal has been performed.

  If the driver's accelerator operation is not performed, that is, if the accelerator pedal is not depressed, and the determination is negative in this step S12, this routine is temporarily executed without executing the subsequent control. finish. On the other hand, if it is determined affirmative in step S12 that the driver has operated the accelerator, that is, that the accelerator pedal has been depressed, the process proceeds to step S13. Then, the vehicle torque limit value grd_trq is read.

  Subsequently, it is determined whether or not the control torque crt_trq is smaller than the limit value grd_trq (step S14). If the control torque crt_trq is greater than or equal to the limit value grd_trq and if a negative determination is made in step S14, this routine is temporarily terminated without executing the subsequent control. On the other hand, if the control torque crt_trq is smaller than the limit torque grd_trq and the determination in step S14 is affirmative, the process proceeds to steps S15 and S16. Then, the driver's driving force change request, that is, the acceleration / deceleration intention is estimated (step S15), and the presence / absence of the driver's acceleration / deceleration intention is determined based on the estimation result (step S16).

  Here, the driver's willingness to accelerate / decelerate can be estimated based on the amount of operation of the accelerator pedal by the driver, the operation speed, or both the operation amount and the operation speed. For example, when the operation amount of the accelerator pedal is larger than a predetermined operation amount, it can be estimated that the driver has an intention to accelerate or decelerate. Alternatively, when the operation speed of the accelerator pedal is faster than a predetermined operation speed, it can be estimated that the driver has an intention to accelerate or decelerate. Alternatively, when both the accelerator pedal operation amount and the operation speed are taken into consideration, the accelerator pedal operation amount is larger than the predetermined operation amount and the accelerator pedal operation speed is faster than the predetermined operation speed. It can be estimated that the person's willingness to accelerate or decelerate is strong. Also, a map for determining the driver's acceleration / deceleration will be set based on the accelerator pedal operation amount and operation speed, and the driver's acceleration / deceleration will be determined based on the map. it can.

  As described above, here, the case where the driver's acceleration request operation is performed in a situation where the reduction in the driving force is restricted when the driving force is reduced by the turning performance improvement control will be described as an example. ing. Therefore, in step S15 and step S16, it is determined whether or not the driver is willing to accelerate.

  If it is determined that there is no driver's acceleration intention and thus a negative determination is made in step S16, this routine is temporarily terminated without executing the subsequent control. The behavior of the vehicle torque act_trq in this case is shown in the time chart of FIG. When it is determined at time t21 that the turning performance improvement control is started, that is, when an execution command for turning performance improvement control is output, the actual vehicle torque act_trq decreases as the control torque ctr_trq decreases. However, the vehicle torque act_trq is limited to a lower value by the vehicle torque limit value grd_trq as described above. Then, even when there is a change in the accelerator opening, for example, when the accelerator pedal is slightly depressed at time t22 in that state, it is determined that the accelerator operation amount does not require a change in the vehicle torque act_trq. In the case of a small value, the vehicle torque act_trq is not changed. That is, the driving force control corresponding to the driver's accelerator operation is not executed. Thus, even if a change in the accelerator opening is detected, if it is estimated that the driver does not intend to accelerate due to the change, the driving force is not changed. It is possible to prevent or suppress application of a change in driving force that is not intended by the driver due to a slight swing of the accelerator pedal.

  On the other hand, when it is estimated that there is an acceleration intention of the driver and the determination is affirmative in step S16, the process proceeds to step S17. Then, it is determined whether or not the estimated acceleration will is large. For example, when the driver's acceleration intention determined from the map based on the operation amount and the operation speed of the accelerator pedal as described above is digitized, and the acceleration intention value is larger than a predetermined value set as a threshold value in advance. If the acceleration will is determined to be large, and the numerical value of the acceleration intention is less than or equal to a predetermined value, it can be determined that the acceleration will is not large.

  If it is estimated that the driver's willingness to accelerate is not large and thus a negative determination is made in step S17, the process proceeds to step S18. Then, a torque change amount up_trq_1 of the vehicle torque act_trq is obtained. This torque change amount up_trq_1 is smaller than the required torque change amount drvreq_trq described above, and corresponds to the driver's acceleration request operation when it is estimated that the driver's acceleration intention is not large as described above. The torque is increased by the driving force control.

  Subsequently, the minimum torque change amount reqtrq_min is obtained (step S19). This minimum torque change amount reqtrq_min is a variable value determined according to the traveling state of the vehicle Ve, and at least the driver feels a change in the driving force with respect to the acceleration operation, that is, the vehicle Ve is in response to the acceleration operation. The torque is set to a magnitude that allows you to feel that you are reacting. The minimum amount of change in the driving force that can be felt by the driver is, for example, “Stimulus discrimination threshold (ΔX) changes in proportion to the intensity of the original stimulus (X) (ΔX / X = const)”. Can be set by applying the idea of Weber's Law. Specifically, if the amount of change in the normal driving force due to the driver's acceleration operation is considered to be “X” in the above-mentioned Weber's law, the “const” portion is identified by experiments, simulations, etc. ΔX ”, that is, the minimum amount of change in driving force that the driver can feel can be determined.

  When the torque change amount up_trq_1 and the minimum torque change amount reqtrq_min are respectively obtained in steps S18 and S19, these values are compared, and it is determined whether or not the torque change amount up_trq_1 is larger than the minimum torque change amount reqtrq_min (step S18). S20).

If the torque change amount up_trq_1 is larger than the minimum torque change amount reqtrq_min and the determination in step S20 is affirmative, the process proceeds to step S21. Then, the driving force of the vehicle Ve is controlled based on the torque change amount up_trq_1. Specifically, a control request torque req_trq output as a control command value for the engine 5 is:
req_trq = act_trq + up_trq_1
It is calculated by the following equation. Then, the output of the engine 5 is controlled based on the calculated control request torque req_trq. In short, in this case, based on the actual vehicle torque act_trq at the time when the driver's acceleration request operation is executed, the vehicle torque act_trq is more than the required torque change amount drvreq_trq corresponding to the change corresponding to the driver's acceleration request operation. By applying the torque change amount up_trq_1 set to a small value, the driving force of the vehicle Ve is controlled. Thereafter, this routine is once terminated.

  The behavior of the vehicle torque act_trq in this case is shown in the time chart of FIG. When the start of turning performance improvement control is determined at time t31, that is, when an execution command for turning performance improvement control is output, the actual vehicle torque act_trq decreases as the control torque ctr_trq decreases. However, the vehicle torque act_trq is limited to a lower value by the vehicle torque limit value grd_trq as described above. If there is a change in the accelerator opening, such as when the accelerator pedal is normally depressed (moderate), for example, at that time t32 in that state, the driver has an intention to accelerate, but the acceleration intention is so large. The vehicle torque act_trq is controlled according to the torque change amount up_trq_1 set in that case. That is, the torque change amount up_trq_1 is applied to the actual vehicle torque act_trq at the time when the driver performs the acceleration request operation (time t32), thereby controlling the vehicle torque act_trq, that is, the driving force of the vehicle Ve.

  By controlling the driving force of the vehicle Ve as described above, an acceleration / deceleration requesting operation by the driver is performed even in a situation where the change in the driving force is restricted due to restrictions on the structure or system of the vehicle Ve. In such a case, it is possible to avoid the occurrence of a phenomenon in which the driving force of the vehicle Ve does not change despite the driver's operation, and to realize a change in the driving force intended by the driver. Further, the torque change amount up_trq_1 at the time of controlling the driving force is set to a value smaller than the required torque change amount drvreq_trq in the control example shown in the flowchart of FIG. Therefore, the driving force is controlled by switching to the driving force control corresponding to the driver's acceleration request operation. As a result, the amount of change in the driving force required for the turning performance improvement control is reduced, and the turning performance improvement control A decrease in the control effect can be suppressed.

On the other hand, if the torque change amount up_trq_1 is equal to or less than the minimum torque change amount reqtrq_min, if the determination is negative in step S20, the process proceeds to step S22. Then, the driving force of the vehicle Ve is controlled based on the minimum torque change amount reqtrq_min. Specifically, a control request torque req_trq output as a control command value for the engine 5 is:
req_trq = act_trq + reqtrq_min
It is calculated by the following equation. Then, the output of the engine 5 is controlled based on the calculated control request torque req_trq. In short, in this case, the driving force of the vehicle Ve is controlled by giving the minimum torque change amount reqtrq_min to the vehicle torque act_trq based on the actual vehicle torque act_trq at the time when the driver's acceleration request operation is executed. The Thereafter, this routine is once terminated.

  The behavior of the vehicle torque act_trq in this case is shown in the time chart of FIG. When it is determined at time t41 that the turning performance improvement control is started, that is, when an execution command for turning performance improvement control is output, the actual vehicle torque act_trq decreases as the control torque ctr_trq decreases. However, the vehicle torque act_trq is limited to a lower value by the vehicle torque limit value grd_trq as described above. Then, at time t42 in that state, if there is a change in the accelerator opening such as a light depression of the accelerator pedal, for example, the driver's intention to accelerate is estimated, but the acceleration intention is estimated to be small. The vehicle torque act_trq is controlled in accordance with the minimum torque change amount reqtrq_min set to. That is, the minimum torque change amount reqtrq_min is applied to the actual vehicle torque act_trq at the time when the driver performs the acceleration request operation (time t42), whereby the vehicle torque act_trq, that is, the driving force of the vehicle Ve is controlled.

  By controlling the driving force of the vehicle Ve as described above, an acceleration / deceleration requesting operation by the driver is performed even in a situation where the change in the driving force is restricted due to restrictions on the structure or system of the vehicle Ve. In such a case, it is possible to avoid the occurrence of a phenomenon in which the driving force of the vehicle Ve does not change in spite of the operation by the driver, and to realize a change in the driving force intended by the driver at a minimum. . Further, the minimum torque change amount reqtrq_min when controlling the driving force is larger than the torque change amount up_trq_1 and smaller than the required torque change amount drvreq_trq in the control example shown in the flowchart of FIG. Therefore, the driving force is controlled by switching to the driving force control corresponding to the driver's acceleration request operation during the turning performance improvement control, resulting in a change in the driving force required by the turning performance improvement control. A decrease in the control effect of the turning performance improvement control due to the decrease in the amount can be minimized.

  On the other hand, when it is estimated that the driver's willingness to accelerate is large and the determination in step S17 is affirmative, the process proceeds to step S23. Then, it is determined whether or not the estimated acceleration will is even greater. For example, as in step S16 described above, the driver's acceleration intention determined from a map based on the accelerator pedal operation amount and operation speed is digitized, and the acceleration intention value is set in step S16. When it is larger than a predetermined value set as a threshold value greater than the threshold value, it is determined that the acceleration intention is further larger.If the acceleration intention value is less than or equal to the predetermined value, the acceleration intention is larger, Can be determined not to be large.

  If it is estimated that the driver's acceleration intention is not even greater, and if a negative determination is made in step S23, the process proceeds to step S24. Then, the required torque change amount drvreq_trq is obtained. This required torque change amount drvreq_trq indicates the change amount of torque to be changed by the driving force control corresponding to the driver's acceleration request operation. Accordingly, in step S5, the required torque change amount drvreq_trq is obtained based on the detection value of the accelerator sensor 13.

When the required torque change amount drvreq_trq is obtained in step S24, the driving force of the vehicle Ve is controlled based on the required torque change amount drvreq_trq. That is, the driving force of the vehicle Ve is controlled by driving force control corresponding to the driver's acceleration request operation (step S25). Specifically, a control request torque req_trq output as a control command value for the engine 5 is:
req_trq = act_trq + drvreq_trq
It is calculated by the following equation. Then, the output of the engine 5 is controlled based on the calculated control request torque req_trq. In short, the control content in this case is the same control content as the control example shown in the flowchart of FIG. 2, and the vehicle torque is based on the actual vehicle torque act_trq at the time when the driver's acceleration request operation is executed. The driving force of the vehicle Ve is controlled by adding to the act_trq the required torque change amount drvreq_trq corresponding to a change corresponding to the driver's acceleration request operation. Thereafter, this routine is once terminated.

  On the other hand, if the driver's willingness to accelerate is estimated to be greater, and if the determination in step S23 is affirmative, the process proceeds to step S26. Then, a torque change amount up_trq_2 of the vehicle torque act_trq is obtained. This torque change amount up_trq_2 is larger than the above-mentioned required torque change amount drvreq_trq, and when it is estimated that the driver's acceleration intention is considerably large as described above, the driver's acceleration request operation is performed. The torque is increased by the corresponding driving force control.

Subsequently, the control request torque req_trq based on the torque change amount up_trq_2 is obtained (step S27), and it is determined whether the control request torque req_trq is larger than the request torque drv_trq (step S28). Specifically, a control request torque req_trq output as a control command value for the engine 5 is:
req_trq = act_trq + up_trq_2
It is calculated by the following equation. Then, the magnitude of the calculated control request torque req_trq and the driver's required torque corresponding to the change in the accelerator opening caused by the driver's acceleration / deceleration request operation, that is, the original when the turning performance improvement control is not performed. The required torque drv_trq is compared with the magnitude.

  If the control request torque req_trq is equal to or less than the request torque drv_trq, and if a negative determination is made in step S28, the process proceeds to step S29. Then, the output of the engine 5 is controlled based on the control request torque req_trq calculated in step S27. In short, in this case, based on the actual vehicle torque act_trq at the time when the driver's acceleration request operation is executed, the vehicle torque act_trq is more than the required torque change amount drvreq_trq corresponding to the change corresponding to the driver's acceleration request operation. By applying the torque change amount up_trq_2 set to a large value, the driving force of the vehicle Ve is controlled. Thereafter, this routine is once terminated.

  On the other hand, if the control request torque req_trq is larger than the request torque drv_trq and the determination is affirmative in step S28, the process proceeds to step S30. Then, the required torque drv_trq is substituted for the control request torque req_trq, and the output of the engine 5 is controlled based on the control request torque req_trq. In short, in this case, the driving force of the vehicle Ve is controlled based on the required torque drv_trq. Therefore, the control request torque req_trq in this case is set so as not to exceed the driver's request torque drv_trq even if it is estimated that the driver's willingness to accelerate is further increased. Thereafter, this routine is once terminated.

  The behavior of the vehicle torque act_trq in this case is shown in the time chart of FIG. When the start of turning performance improvement control is determined at time t51, that is, when an execution command for turning performance improvement control is output, the actual vehicle torque act_trq decreases as the control torque ctr_trq decreases. However, the vehicle torque act_trq is limited to a lower value by the vehicle torque limit value grd_trq as described above. If there is a change in the accelerator opening, for example, when the accelerator pedal is strongly depressed at time t52 in that state, it is estimated that the driver's willingness to accelerate is considerably large, and the torque set in that case The vehicle torque act_trq is controlled according to the change amount up_trq_2. That is, the torque change amount up_trq_2 is applied to the actual vehicle torque act_trq at the time when the driver performs the acceleration request operation (time t52), thereby controlling the vehicle torque act_trq, that is, the driving force of the vehicle Ve. Then, as shown after time t53, when the control request torque req_trq becomes larger than the request torque drv_trq, thereafter, the driving force of the vehicle Ve is controlled based on the driver's request torque drv_trq. That is, the driving force of the vehicle Ve is controlled by the normal driving force control corresponding to the driver's acceleration / deceleration request operation.

  By controlling the driving force of the vehicle Ve as described above, an acceleration / deceleration requesting operation by the driver is performed even in a situation where the change in the driving force is restricted due to restrictions on the structure or system of the vehicle Ve. In such a case, it is possible to avoid the occurrence of a phenomenon in which the driving force of the vehicle Ve does not change despite the driver's operation, and to realize a change in the driving force intended by the driver. Further, the torque change amount up_trq_2 when controlling the driving force is set to a value larger than the required torque change amount drvreq_trq in the control example shown in the flowchart of FIG. Even if it is estimated to be large, the driving force control that well reflects the driver's intention can be executed. Furthermore, even in such a case, since the control request torque req_trq is set so as not to exceed the driver's request torque drv_trq, the driving force is controlled with a torque change amount exceeding the driver's request torque drv_trq. It is possible to prevent excessive acceleration due to being performed.

  As described above, according to the vehicle control apparatus of the present invention, when the vehicle Ve is turning, the turning performance improvement control for automatically controlling the driving force of the vehicle Ve and stabilizing the vehicle behavior during the turning is performed. Executed. And, in the situation where the execution of the driving force control is restricted due to the constraints on the configuration of the vehicle Ve during the execution of the driving force control in the turning performance improvement control, the change direction of the driving force by the driving force control When the driving force change request operation, that is, acceleration / deceleration request operation by the driver in the opposite direction is performed, for example, in the situation where the driving force control in the turning performance improvement control restricts the reduction of the driving force, When an acceleration request operation is performed, or when a driver's deceleration request operation is performed in a situation where the increase in driving force is restricted by the driving force control in the turning performance improvement control, the acceleration request operation or The amount of change in the driving force corresponding to the acceleration requesting operation or the deceleration requesting operation (that is, the requested torque change amount drvreq_trq) with respect to the actual driving force (that is, the actual vehicle torque act_trq) at the time when the deceleration requesting operation is performed Torque variation Up_trq_2, by torque variation Up_trq_1, such as a torque variation Up_trq_2) is applied, the driving force of the vehicle Ve is controlled. Therefore, even if the change in driving force is restricted due to restrictions on the structure and system of the vehicle Ve, when the driver performs an acceleration / deceleration request operation, the driver operates it. It is possible to avoid the occurrence of a phenomenon in which the driving force of the vehicle Ve does not change, and to realize a change in the driving force intended by the driver.

  Here, the relationship between the above-described specific example and the present invention will be briefly described. Functional means for executing steps S4 to S6, steps S20 to S22, and steps S23 to S30 are “driving force correcting means” in the present invention. It corresponds to. The functional means for executing steps S15 to S17, S23 corresponds to the “estimating means” in the present invention.

  DESCRIPTION OF SYMBOLS 1,2 ... Front wheel, 3, 4 ... Rear wheel, 5 ... Driving force source, 6 ... Electronic control unit (ECU) 7, 8, 9, 10 ... Brake device, 11 ... Brake actuator, 15 ... Wheel speed sensor, 16 ... longitudinal acceleration sensor, 17 ... lateral acceleration sensor, 18 ... yaw rate sensor, Ve ... vehicle.

Claims (4)

In a vehicle control device capable of executing a turning improvement control for controlling a driving force of a vehicle to stabilize a vehicle behavior during turning,
When the driving force change request operation by the driver in the direction opposite to the driving force change direction by the driving force control is performed when the execution of the driving force control in the turning performance improvement control is restricted. Driving force correction means for controlling the driving force by applying a change amount of the driving force corresponding to the change request operation to an actual driving force of the vehicle at the time when the change request operation is performed. A control apparatus for a vehicle.
When the change request operation is performed, the apparatus further includes an estimation unit that estimates the magnitude of the driver's driving force change request using at least one of the operation amount and the operation speed of the change request operation as an index,
The driving force correction means uses the required driving force corresponding to the change request operation in the normal time when the driving force control is not performed as the upper limit of the corrected driving force, and the amount of change to be applied to the actual driving force, The vehicle control device according to claim 1, further comprising means for increasing the estimated driving force change request as the estimated driving force change request increases.
2. The drive force correcting means includes means for setting a lower limit of the change amount that allows the driver to experience a change in the drive force caused by applying the change amount. Or the control apparatus of the vehicle of 2.
  The said driving force correction | amendment means includes a means to make the said variation | change_quantity 0 when the magnitude | size of the said estimated driving force change is smaller than predetermined value. Vehicle control device.

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