JP5724783B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a control apparatus for a vehicle that controls the driving force and braking force of the vehicle to improve the steering characteristics of the vehicle and stabilize the vehicle behavior during turning.

  Developed technology to stabilize the steering characteristics of the vehicle and improve the turning performance of the vehicle by automatically controlling the driving force and braking force generated in the vehicle in conjunction 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 motion control device for the purpose of reliably reducing a side slip of a vehicle and improving safety performance. The vehicle motion control device described in Patent Document 1 is a vehicle motion control device capable of independently controlling the driving force and braking force of four wheels, and is based on an acceleration / deceleration control command linked to the lateral motion of the vehicle. Based on the first mode for generating substantially the same driving force or braking force on the left and right wheels and the yaw moment control command calculated from the side slip information of the vehicle, different driving force or braking force for the left and right wheels The first mode is selected when the yaw moment command is smaller than a predetermined value, and the second mode is selected when the yaw moment command is larger than the predetermined value. It is configured as follows. Further, this Patent Document 1 discloses a configuration in which the vehicle is controlled to decelerate when the lateral acceleration of the vehicle increases, and is controlled to accelerate when the lateral acceleration of the vehicle decreases. Yes.

  Patent Document 2 discloses rollover suppression control that suppresses roll of a vehicle when a parameter corresponding to the roll behavior of the vehicle becomes larger than a preset control start determination reference value when the vehicle turns. An invention relating to a rollover suppression control device for a vehicle that ends rollover suppression control when a parameter becomes smaller than a preset control end determination reference value is described. The vehicle rollover suppression control device described in Patent Document 2 uses the control end determination reference value at the time of steady rotation as the control end determination reference value when the vehicle turns at a normal rotation, and turns the vehicle. Is an unsteady rotation control end determination reference value that is smaller than the steady rotation control end determination reference value.

  Patent Document 3 describes an invention relating to a vehicle stabilizer system configured such that a roll restraining force generated by a stabilizer bar can be changed by operating an actuator. In Patent Document 3, when the vehicle accelerates or decelerates during turning, the cornering power of the front and rear wheels changes due to load movement in the front-rear direction of the vehicle. As a result, the steering characteristic (stability factor) of the vehicle is increased. Changes are disclosed.

  Patent Document 4 discloses a vehicle driving force control apparatus that appropriately maintains a wheel grip force by reducing an output of a driving force source, and detects a steering angle, a lateral acceleration, and a yaw rate of the vehicle. The target yaw rate is calculated based on the detected steering angle, and the torque reduction amount is calculated using at least the detected lateral acceleration and the comparison result between the detected yaw rate and the calculated target yaw rate. An invention relating to a driving force control apparatus for a vehicle configured to reduce the output of a driving force source based on the torque reduction amount is described.

JP 2010-162911 A JP 2005-271820 A JP 2009-202621 A JP 2009-185672 A

  In the invention described in Patent Document 1, the acceleration / deceleration of the vehicle, that is, the driving force and the braking force of the vehicle are automatically controlled in conjunction with the driver's steering operation. For example, as described above, when the lateral acceleration of the vehicle decreases due to the steering operation, the vehicle is controlled to accelerate. When the lateral acceleration of the vehicle increases due to the steering operation, the vehicle is controlled to decelerate. Therefore, the occurrence of skidding of the vehicle can be suppressed. However, for example, when a quick lane change is performed, or when a steering turning operation for increasing the steering angle and a steering returning operation for returning the steering angle to 0 are repeatedly performed within a short time, etc. The driver may feel uncomfortable with changes in driving force or braking force controlled based on such steering operation.

  Specifically, as shown in FIG. 14, for example, when the steering turning operation and the returning operation are repeated within a short time, the lateral acceleration increases due to the steering turning operation. As a result, the control torque decreases. That is, the driving force of the vehicle is reduced or the braking force is increased. Thereafter, the lateral acceleration is decreased by the steering return operation, and the control torque is temporarily increased accordingly. However, when the steering is continuously turned in the direction opposite to the initial direction, the lateral acceleration is generated again, and the control torque is decreased again accordingly. Therefore, when the driving force and braking force of the vehicle are automatically controlled based on the driver's steering operation and the lateral acceleration of the vehicle caused by the steering operation, the steering turning operation and the returning operation are repeated within a short time. In this case, the driving force reduced by the first cutting operation once increases and then immediately decreases again, which may give the driver a sense of incongruity.

  As described above, in order to improve the turning performance of the vehicle or to stabilize the vehicle behavior when turning, the driving force and braking force of the vehicle are automatically controlled based on the steering operation of the driver and the lateral acceleration of the vehicle. In addition, there is still room for improvement in order to appropriately execute the control without causing the driver to feel uncomfortable or shocked.

  The present invention has been made paying attention to the technical problem described above, and is suitable for driving force control and braking force control for stabilizing vehicle behavior during cornering without causing the driver to feel uncomfortable or shocking. It is an object of the present invention to provide a vehicle control apparatus that can be executed in the first place.

In order to achieve the above-mentioned object, the invention according to claim 1 corrects and changes the driving force or the braking force based on the steering angle of the vehicle and the lateral acceleration in the axle direction, thereby changing the vehicle behavior during turning. In a vehicle control device capable of performing a stable braking / driving force control, an operation time and / or an operation speed in a steering turning operation in which the steering angle increases from 0 and a steering return operation in which the steering angle decreases toward 0 are set. Steering operation detection means for detecting, and when the steering turning operation and the steering return operation are performed, based on the operation time or the operation speed, the driving force or the braking force by the correction in the braking / driving force control the rewritable sets the change speed when changing the, the steering turning operation row Depending on the operating time in which a control device, characterized in that the steering wheel return operation and a braking driving force setting means for limiting the rate of change in time to be performed.

The invention according to claim 2 is the invention according to claim 1, wherein when the steering operation detecting means performs the steering return operation, the steering angle at the start time of the steering return operation and the steering return operation time. On the basis of the operation speed of the steering wheel, the steering return operation and the steering turning operation are estimated to be performed continuously, and the braking / driving force setting means includes the steering return operation, the steering turning operation, Is a control device including means for limiting the rate of change when the steering return operation is performed when it is estimated that the steering is performed continuously.

And, the invention of claim 3 is the invention of any one of claims 1 to 3, wherein the braking-driving force setting means for limiting the changing speed by performing a filtering process to the control amount in the braking-driving force control A control device comprising means.

  According to the first aspect of the present invention, the driving force or the braking force when the vehicle is turning based on the steering angle of the vehicle that is increased or decreased by the driver's steering operation and the lateral acceleration of the vehicle caused by the steering operation. The braking / driving force control for correcting and changing the above is executed. In this case, the operation time and / or operation speed in the steering operation, that is, the steering turning operation and the steering return operation, is detected, and the change speed at the time of correction in the braking / driving force control is determined based on the operation time or operation speed. . Therefore, even when the steering turning operation and the steering returning operation are performed continuously or repeatedly, it is possible to execute the braking / driving force control by setting a change speed that does not cause the driver to feel uncomfortable. it can. As a result, braking / driving force control that stabilizes the vehicle behavior during turning and improves the turning performance of the vehicle can be appropriately executed without causing the driver to feel uncomfortable or shocked.

Also, if the scan tearing cut operation is performed, at the time of steering cuts after operation steering wheel return operation in accordance with the operation time or operation rate when the steering turning operation has been performed, when the correction in the braking-driving force control The rate of change is limited. For example, the change speed is limited to be slower as the operation time of the steering turning operation is shorter or the operation speed is faster. Therefore, even when the steering turning operation and the steering return operation are performed continuously or repeatedly, the driving force or braking force corrected in the braking / driving force control can be changed smoothly. As a result, it is possible to appropriately execute the braking / driving force control while avoiding or suppressing the change of the driving force or the braking force that gives the driver a sense of incongruity.

According to the invention of claim 2 , when the steering return operation is performed, the steering angle at the time when the steering return operation is started, and the operation speed when the steering return operation is performed, that is, the steering angular velocity is Based on the detected steering angle and operation speed, it is estimated whether or not the steering turning operation is continuously performed after the steering return operation. Then, when it is estimated that the steering turning operation is continuously performed after the steering returning operation, the changing speed at the time of correction in the braking / driving force control is limited. That is, the driving force or braking force corrected in the braking / driving force control is smoothly changed. Therefore, even when the steering return operation and the steering turning operation are performed continuously or repeatedly, the braking / driving force is avoided or restrained from changing the driving force or braking force that gives the driver a sense of incongruity. Control can be executed appropriately.

According to the invention of claim 3, when the braking / driving force control is executed when the steering turning operation or the steering returning operation is performed, the correction amount at the time of correction in the braking / driving force control is, for example, a low-pass filter. By applying the filtering process such as the above, the speed of change at the time of correction in the braking / driving force control is limited. Therefore, it is possible to reliably avoid or suppress a change in driving force or braking force that causes the driver to feel uncomfortable in the braking / driving force control.

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 flowchart for demonstrating an example of control by the control apparatus of this invention. FIG. 3 is a schematic diagram for explaining an example of a map for obtaining a change amount and a change speed of braking / driving force in a range that does not give the driver a sense of incongruity when the control shown in FIG. 2 is executed. It is a schematic diagram for demonstrating how to obtain | require in the case of calculating | requiring the variation | change_quantity and change speed of braking / driving force using the map shown in FIG. FIG. 3 is a schematic diagram for explaining a difference between a case where a restriction is provided for correction of braking / driving force and a case where no restriction is provided when the control shown in FIG. 2 is executed. It is a schematic diagram for demonstrating the difference between the influence of a lateral acceleration in the case of performing control by the control apparatus of this invention, and the influence of a lateral jerk. FIG. 3 is a time chart for explaining a change in steering angle and control torque when the control shown in FIG. 2 is executed. FIG. An example of a map for obtaining the amount of change and the speed of change of braking / driving force in a range that does not give the driver a sense of incongruity particularly when steering turning operation and returning operation are performed when the control shown in FIG. 2 is executed. It is a schematic diagram for demonstrating. It is a flowchart for demonstrating the other control example by the control apparatus of this invention. It is a schematic diagram for demonstrating the difference between the case where a restriction | limiting is provided in correction | amendment of braking / driving force, and the case where it does not provide when performing control shown in FIG. FIG. 10 is a time chart for explaining a change in steering angle and control torque when the control shown in FIG. 9 is executed. FIG. It is a flowchart for demonstrating the other control example by the control apparatus of this invention. FIG. 13 is a time chart for explaining a steering angle and a change in control torque when the control shown in FIG. 12 is executed. FIG. It is a time chart for demonstrating the transition of a steering angle, control torque, etc. at the time of performing the conventional control.

  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 can control the driving force and braking force of the vehicle independently of driving operations such as an accelerator operation and a brake operation by the driver. That is, the vehicle targeted by the present invention has a configuration capable of automatically controlling the driving force and the braking force separately from the control of the driving force and the braking force of the vehicle based on the driving operation by the driver. Yes. 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. And it is comprised as a rear-wheel drive vehicle which drives the rear-wheels 3 and 4 with the motive power which the driving force source 5 outputs.

  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 (see FIG. Not shown) is used. When the electric motor is mounted on the vehicle Ve as the driving force source 5, for example, an electric storage device (none of which is shown) such as a battery or a capacitor is connected to the electric motor via an inverter.

  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 can be automatically and individually controlled by controlling the operation state of each brake device 7, 8, 9, 10 by the electronic control device 6. Is possible.

  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 a depression angle (or depression amount or accelerator opening) of an accelerator pedal (not shown) and a depression angle (or depression amount or brake opening) of a brake pedal (not shown) are detected. A brake sensor 13, a steering angle sensor 14 for detecting a steering angle of a steering wheel (not shown), a wheel speed sensor 15 for detecting rotational speeds (wheel speeds) of the drive wheels 1, 2, 3 and 4, and a vehicle Ve A longitudinal acceleration sensor 16 that detects acceleration (ie, longitudinal acceleration) in the longitudinal direction (vertical direction in FIG. 1), and an axle direction (horizontal direction in FIG. 1) of the vehicle Ve, ie, lateral acceleration (ie, lateral acceleration). The lateral acceleration sensor 17 for detecting, the yaw rate sensor 18 for detecting the yaw rate of the vehicle Ve, or the output torque of the driving force source 5 Detection signals from a torque sensor for detecting (not shown) is configured to be inputted to the electronic control unit 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, by changing the driving force and braking force of the vehicle Ve to control the yaw rate of the vehicle Ve, that is, by executing so-called braking / driving force control, the actual steering characteristic of the vehicle Ve is changed to the target steering characteristic. 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. The yaw rate of the vehicle Ve can be controlled, for example, by performing the braking / driving force control 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 2, 3 or the braking torque applied to the wheels 1, 2, 3, 4, the vehicle Ve The yaw rate can be controlled. As described above, the control for setting the target yaw rate and causing the actual yaw rate of the vehicle Ve to follow the target yaw rate is well known as described in, for example, Japanese Patent Application Laid-Open No. 5-278488. Therefore, more specific description is omitted.

  By performing braking / driving force control on the vehicle Ve that is turning as described above, the steering characteristics of the vehicle Ve can be brought close to the target steering characteristics, and the turning performance of the vehicle Ve can be improved. Therefore, by increasing the correction amount in the braking / driving force control, that is, the amount of change in the driving force or the braking force, the control responsiveness when controlling the actual steering characteristics of the vehicle Ve is improved, and the vehicle Ve is improved. This will also improve the turning performance. However, if the amount of correction of the driving force or braking force is increased, the driving force or braking force in the braking / driving force control will change greatly, and as a result, the driver will feel uncomfortable and shock, and the drivability will decrease accordingly. There is a possibility that. Therefore, it is desirable to increase the correction amount in the above braking / driving force control as much as possible within a range in which the driver does not feel uncomfortable or shocked.

  Therefore, the vehicle control device according to the present invention executes the braking / driving force control based on the lateral acceleration of the vehicle Ve and the jerk which is a differential value of the lateral acceleration in addition to the information such as the vehicle speed and the steering angle of the vehicle Ve. By doing so, the braking / driving force control can be executed so that the effect of improving the turning performance can be as large as possible without causing the driver to feel uncomfortable or shock.

  Further, the steering operation by the driver is not always performed when the vehicle Ve is turned as described above. For example, when the vehicle Ve is traveling on a multi-lane road, when the lane in which the vehicle Ve is traveling is changed, or when an obstacle or danger on the front road is avoided, the steering operation by the driver is not performed. Done. The steering operation in such a case is usually performed quickly within a short time. That is, the steering angle is increased from a state in which the vehicle is traveling straight ahead and the steering angle is almost zero, and the steering turning operation is performed, and a state of a predetermined steering angle larger than 0 by performing the steering turning operation. Thus, the so-called steering return operation in which the steering angle is decreased toward 0 is performed continuously or repeatedly within a short time. As described above, when the steering turning operation and the returning operation as described above are performed continuously or repeatedly, a change in driving force or braking force controlled based on the steering operation causes the driver to There was a possibility of giving a sense of incongruity.

  Therefore, in the vehicle control device according to the present invention, even when the steering turning operation and the returning operation are performed continuously or repeatedly, the change speed at the time of correction in the braking / driving force control is limited. Thus, the braking / driving force control can be appropriately executed without causing the driver to feel uncomfortable or shock.

  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, first, the actual turning state of the vehicle Ve is estimated from detected values such as the steering angle and yaw rate of the vehicle Ve, and the vehicle Ve based on braking / driving force control is determined from the deviation between the actual turning state and the target turning state of the vehicle Ve. A change amount (correction amount) Fctrl of the driving force or braking force is calculated (step S101). Here, the turning state of the vehicle Ve is a factor obtained based on detected values such as the vehicle speed, acceleration, steering angle, and yaw rate of the vehicle Ve. For example, a star indicating the degree of oversteer or understeer during turning. It is expressed by a possibility factor.

  Next, the lateral acceleration Gy and the lateral jerk DGy of the vehicle Ve are obtained (step S102). The lateral acceleration Gy is the acceleration in the axle direction of the vehicle Ve, that is, the lateral direction, and can be obtained from the detection value of the lateral acceleration sensor 17 as described above. The jerk is a value obtained by differentiating acceleration with respect to time, and is called so-called jerk or jerk. Therefore, the lateral jerk DGy is a jerk in the axle direction of the vehicle Ve, that is, in the lateral direction, and can be obtained by time-differentiating the lateral acceleration Gy obtained from the detection value of the lateral acceleration sensor 17 described above. As an effect of acceleration and jerk on the driver, the driver is more sensitive to jerk than acceleration. Therefore, by considering the lateral jerk DGy in the lateral direction of the vehicle Ve in addition to the lateral acceleration Gy as described above, the braking / driving force control of the present invention can be performed with higher degree or more accuracy.

  This is the upper limit value of the changing speed in the correction in the braking / driving force control from the variation Fctrl of the braking / driving force control obtained in the above steps S101 and S102 and the lateral acceleration Gy or the lateral jerk DGy of the vehicle Ve. The maximum change speed DFctrl1 is obtained (step S103). As a method for obtaining the maximum change speed DFctrl1, for example, the change amount (correction amount) and change speed of the driving force and the braking force that change due to the correction in the braking / driving force control for each magnitude of the lateral acceleration Gy of the vehicle Ve. Accordingly, a range or a range of values in which the driver feels uncomfortable is obtained experimentally or empirically, and is prepared in advance as a constant map or an arithmetic expression. Then, the maximum change speed DFctrl1 is obtained based on the constant map or the arithmetic expression corresponding to the lateral acceleration Gy obtained in step S102.

  An example of a constant map for obtaining the maximum change speed DFctrl1 is shown in FIGS. 3 and 4, an area indicated by a curve BL is an area in which the driver does not feel uncomfortable when correction is performed at a predetermined change amount and a predetermined change speed in the braking / driving force control (FIG. 3). FIG. 4 is a boundary line between a hatched portion in FIG. 4 and a region (a portion not hatched in FIG. 3 and FIG. 4) that is considered uncomfortable. As shown in FIG. 3, when the lateral acceleration Gy of the vehicle Ve increases, the curve BL as a boundary line tends to move to the right side of FIG. That is, as a criterion for determining whether or not the driver feels uncomfortable when correcting the driving force or the braking force in the braking / driving force control described above, if the lateral acceleration Gy of the vehicle Ve increases, the braking / driving force control described above is performed. There is a tendency that the area where the driver does not feel uncomfortable during the correction at the time is enlarged. In other words, as the lateral acceleration Gy of the vehicle Ve is larger, the upper limit value of the change amount Fctrl and the upper limit value of the change speed within a range in which the driver does not feel uncomfortable at the time of correction in the braking / driving force control (that is, Maximum change rate) DFctrl1 tends to increase.

  When obtaining the maximum change speed DFctrl1 using the constant map, a constant map corresponding to the lateral acceleration Gy obtained in step S102 is first selected as shown in FIG. The maximum change speed DFctrl1 is obtained as the upper limit value of the change speed in the region in which the driver does not feel uncomfortable with the change amount Fctrl of the braking / driving force control obtained in the above. When the change amount Fctrl of the braking / driving force control obtained in step S101 is out of the region where the driver does not feel uncomfortable, the change amount Fctrl is decreased until it falls within the region where the driver does not feel discomfort. Thereafter, the maximum change speed DFctrl1 corresponding to the reduced change amount Fctrl is obtained.

  When the maximum change speed DFctrl1 in the correction in the braking / driving force control is obtained in step S103, the correction when the braking / driving force control is executed is limited (step S104). That is, the correction is limited so that the change amount and the change speed at the time of correction in the braking / driving force control become the change amount Fctrl and the maximum change speed DFctrl1 obtained above. Specifically, as indicated by a one-dot chain line in the time chart of FIG. 5, the change rate is limited by the maximum change rate DFctrl1, and the maximum value of the change amount at the time of correction is limited by the change amount Fctrl.

  Note that the state represented by the broken line in the time chart of FIG. 5 indicates the state of change in the driving force or braking force when the correction by the maximum change speed DFctrl1 is not limited as described above. In this case, since the maximum value of the change speed at the time of correction is not limited, the change in driving force or braking force rises by the change amount Fctrl with good responsiveness. On the other hand, since the change amount Fctrl suddenly rises, as shown in FIG. 5, a sudden change occurs in the driving force or braking force of the vehicle Ve, which causes the driver to feel uncomfortable or shocked. On the other hand, the change in the driving force or braking force of the vehicle Ve at the time of correction is shown in FIG. 5 by limiting the maximum value of the changing speed at the time of correction by the maximum change speed DFctrl1 as in the present invention. As a result, it gradually increases, thereby preventing or suppressing the occurrence of a sense of discomfort and shock to the driver.

  In the above description of steps S103 and S104, an example is shown in which the driving force or the braking force in the braking / driving force control is corrected based on the lateral acceleration Gy, but the lateral jerk is substituted for the lateral acceleration Gy. The braking / driving force control can be executed based on DGy. That is, in each of the above steps S103 and S104, the maximum change speed DFctrl1 in the braking / driving force control is determined from the braking / driving force control variation Fctrl obtained in each of the above steps S101 and S102 and the lateral jerk DGy of the vehicle Ve. Can be requested.

  In the maps shown in FIGS. 3 and 4, when the lateral jerk DGy is used, the larger the lateral jerk DGy of the vehicle Ve, the larger the lateral jerk DGy of the vehicle Ve is. There is a tendency that the maximum change speed DFctrl1 within a range in which the driver does not feel uncomfortable during the correction. Therefore, even when the lateral jerk DGy is used instead of the lateral acceleration Gy, the control can be executed in the same manner as when the lateral acceleration Gy described above is used.

  Thus, in the vehicle control apparatus according to the present invention, more appropriate braking / driving force control can be executed by considering the lateral acceleration Dy and the lateral jerk DGy of the vehicle Ve. For example, when the vehicle Ve turns, as shown in FIG. 6, the vehicle Ve travels again through the acceleration section in the straight traveling from the deceleration section in the straight traveling through the corner entrance section, the corner intermediate section, and the corner exit section. In this case, the lateral acceleration Gy and the lateral jerk DGy generated in the vehicle Ve are relatively small in the corner entrance section and the corner exit section, and conversely, the lateral jerk DGy is relatively large. In the corner intermediate section, the lateral acceleration Gy is relatively large, and conversely, the lateral jerk DGy is relatively small.

  Therefore, when the above-described braking / driving force control is executed during turning of the vehicle Ve, the above-described braking / driving force control is performed based on the lateral jerk DGy in the corner entrance section and the corner exit section where the influence of the lateral jerk DGy becomes large. On the contrary, in the corner intermediate section where the influence of the lateral acceleration Gy is large, the above braking / driving force control in the present invention is more appropriately performed by executing the above braking / driving force control based on the lateral acceleration Gy. Can be executed.

  When the correction amount when executing the braking / driving force control is limited in step S104, the steering angle (steering angle) δ and the steering angular velocity (steering angular velocity) Dδ of the vehicle Ve are subsequently obtained (step S105). The steering angle δ can be detected by the steering angle sensor 14 described above. The steering angular velocity Dδ can be obtained by differentiating the steering angle δ with respect to time.

  When the steering angle δ and the steering angular velocity Dδ are obtained, the steering operation state is determined based on the steering angle δ and the steering angular velocity Dδ (step S106). That is, as the steering operation, a so-called steering turning operation and steering return operation are determined. For example, as shown in FIG. 7, when the steering angle δ increases from 0 in the positive (+) or negative (−) direction, it can be determined that the steering turning operation has been performed. On the other hand, when the steering angle δ decreases from a predetermined value in the positive (+) or negative (−) direction toward 0, it can be determined that the steering return operation has been performed. . Further, from the steering angular speed Dδ when the steering turning operation or the returning operation is performed, it is possible to determine the speed of the steering turning operation or the returning operation, that is, the operation speed.

  Then, an elapsed time T from when the steering operation is started is obtained (step S107), and then it is determined whether or not a return operation is performed after the steering operation is performed (step S108). ). This can be determined from the detected value of the steering angle δ as described above.

  If a negative determination is made in step S108 because the steering turning operation or the returning operation has not yet been performed, or the steering returning operation has not been performed after the steering turning operation, the process proceeds to step S109. Then, the correction content determined in the above-described step S104 (the correction content defined by the change amount Fctrl and the maximum change speed DFctrl1) is output. That is, the above correction is limited so that the change amount and the change speed at the time of correction in the braking / driving force control become the change amount Fctrl and the maximum change speed DFctrl1 obtained in step S104 described above, respectively. Specifically, the change rate is limited by the maximum change rate DFctrl1, and the maximum value of the change amount at the time of correction is limited by the change amount Fctrl. In short, in this case, the normal braking / driving force control in the present invention is executed. Thereafter, this routine is once terminated.

  On the other hand, if a positive determination is made in step S108 because the return operation has been performed after the steering turning operation, the process proceeds to step S110 and is based on the elapsed time T obtained in step S107. Thus, the maximum change speed DFctrl2 is obtained. The maximum change speed DFctrl2 is controlled so as not to give the driver a sense of incongruity when the steering turning operation and the returning operation are performed when the braking / driving force control according to the present invention is executed. This is for limiting the speed of change of the driving force or braking force in force control.

  As a method of obtaining the maximum change speed DFctrl2, for example, the change speed of the driving force or the braking force at which the driver does not feel uncomfortable is obtained in advance experimentally or empirically, for example, a constant map as shown in FIG. Prepared in advance. Based on the elapsed time T obtained in step S107 and the constant map as shown in FIG. 8, the maximum change speed DFctrl2 is obtained. In the example of the constant map shown in FIG. 8, the maximum change speed DFctrl2 is set to be smaller as the elapsed time T is shorter, that is, the change speed of the driving force or braking force in the braking / driving force control is strongly limited. Has been. Therefore, the shorter the time from when the steering turning operation is performed to when the returning operation is performed, the slower the change rate of the driving force or braking force in the braking / driving force control is limited.

  In the above description of step S110, an example is shown in which the maximum change rate DFctrl2 is obtained from a constant map. For example, the sprung resonance frequency of the vehicle Ve is obtained in advance and the period of the sprung resonance frequency is used as a reference. Thus, when the elapsed time T is short, the maximum change speed DFctrl2 can be set so that the change speed of the driving force or braking force in the braking / driving force control becomes more gradual. Further, when the elapsed time T is shorter than a predetermined time set in advance as a threshold, the maximum change speed DFctrl2 having a value smaller (slower) than the aforementioned maximum change speed DFctrl1 is set, and the elapsed time T is longer than the predetermined time. In this case, the maximum change rate DFctrl1 described above may be set. Further, as will be described later, for example, by performing a filtering process such as a low-pass filter, it is possible to limit the change speed of the driving force or braking force in the braking / driving force control.

  When the maximum change speed DFctrl2 in the correction in the braking / driving force control is obtained in step S110, the correction when the braking / driving force control is executed is limited (step S111). That is, the correction is limited so that the change amount and the change speed at the time of correction in the braking / driving force control become the change amount Fctrl and the maximum change speed DFctrl2 obtained above, respectively. Specifically, as indicated by a solid line in the time chart of FIG. 6, the change rate at the time of correction is limited by the maximum change rate DFctrl2, and the maximum value of the change amount at the time of correction is limited by the change amount Fctrl. .

  Then, when the correction in the case of executing the braking / driving force control is restricted in step S111, the process proceeds to the above-described step S109, and is defined by the correction content (change amount Fctrl and maximum change speed DFctrl2) determined in step S111. Correction details) is output. That is, the braking / driving force control is executed based on the correction content limited in step S111. Thereafter, this routine is once terminated.

  As shown in the flowchart of FIG. 2, when the braking / driving force control of the present invention is executed, the control torque in the braking / driving force control, that is, the torque fluctuation state corresponding to the change in the driving force or the braking force is shown. This is shown in the time chart of FIG. In the time chart of FIG. 7, when the steering turning operation starts at time t1, the control torque decreases. That is, in the braking / driving force control, the driving force is reduced or the braking force is increased. Then, the steering return operation is started at time t2. For example, in the case where the turning operation of the steering is a turning operation in which the vehicle Ve turns around a corner or a curved road, the elapsed time T from the start of the turning operation of the steering to the return operation becomes relatively long. When the angle returns to 0, a series of steering operations are once completed.

  However, as shown in the time chart of FIG. 7, for example, when a lane change or a sharp steering wheel is performed, the elapsed time T is relatively short, and the steering angle returns to 0 by the steering return operation. However, the steering angle continuously increases in the direction opposite to the initial steering turning operation. That is, the steering operation is performed in the opposite direction to the initial steering operation. In this case, in the conventional control as shown in FIG. 14, the control torque is increased by the steering return operation, and then the control torque is decreased again by the steering turning operation. That is, as shown between the time t2 and the time t4 in the time chart of FIG. 14, the control torque once increases, and then the control torque decreases again immediately thereafter. Therefore, in the conventional control as shown in FIG. 14 described above, when the steering turning operation and the returning operation are performed within a short time, for example, by changing the lane or by a sharp steering wheel, the control torque as described above is used. The driver may feel uncomfortable due to the fluctuation of the vehicle.

  On the other hand, in the braking / driving force control according to the present invention shown in the flowchart of FIG. 2, when the steering turning operation and the returning operation are performed within a short time as described above, the steering returning operation is performed. Depending on the elapsed time T, that is, the operation time of the steering turning operation, the change speed of the control torque is limited to be slow. That is, the upper limit value of the change amount and the change speed at the time of correction in the braking / driving force control is limited to be low. Therefore, as shown from the time t2 to the time t4 in the time chart of FIG. 7, the increase in the control torque is suppressed, and the control torque varies gently. Therefore, according to the braking / driving force control in the present invention shown in the flowchart of FIG. 2, even when the steering turning operation and the returning operation are performed within a short time, for example, by changing the lane or by a sharp handle, It can be avoided that the driver feels uncomfortable due to the fluctuation of the control torque as in the conventional control example.

  FIG. 9 is a flowchart for explaining another example of control by the control device according to the present invention. The routine shown in this flowchart is repeatedly executed every predetermined short time. In the flowchart of FIG. 9, the control content of each step from step S201 to step S206 is the same as the control content of each step from step S101 to step S106 in the flowchart of FIG. Detailed description is omitted.

  In the flowchart of FIG. 9, when it is determined in step S206 that the steering operation state, that is, the steering turning operation and the steering returning operation state is performed, the process proceeds to step S207, where the steering operation state is changed from the steering returning operation. It is determined whether the operation changes continuously. Specifically, it is determined whether or not the absolute value of the steering angle δ is equal to or smaller than the reference value A and the absolute value of the steering angular velocity Dδ is equal to or larger than the reference value B. Here, each of the reference values A and B is a threshold value set in advance to estimate whether or not the steering operation state continuously changes from the steering return operation to the cutting operation. Therefore, in this step S207, it is determined whether or not a relatively quick steering return operation has been performed under the condition of a relatively small steering cut amount, that is, the steering angle δ.

  As described above, when the vehicle Ve is turning on a corner or a curved road, the steering angle δ has a relatively large steering angle δ and is relatively slow, that is, at a relatively slow steering angular velocity Dδ. An operation and a return operation are performed. On the other hand, for example, when the steering turning operation and the returning operation are continuously performed or repeated within a short period of time, such as when changing lanes or a sharp steering wheel, the steering angle δ is relatively small, A steering turning operation and a returning operation are performed at a fast, that is, relatively fast steering angular velocity Dδ. Therefore, in this step S207, when the steering turning operation and the returning operation are performed with the relatively small steering angle δ and the relatively fast steering angular velocity Dδ, that is, the absolute value of the steering angle δ is the reference value A. The steering operation state is estimated to be a state that continuously changes from the steering return operation to the cutting operation when the absolute value of the steering angular velocity Dδ is equal to or greater than the reference value B.

  Therefore, when the absolute value of the steering angle δ is larger than the reference value A and / or the absolute value of the steering angular velocity Dδ is smaller than the reference value B, the steering operation state is continuously changed from the steering return operation to the cutting operation. In this step S207, a negative determination is made. If a negative determination is made in step S207, the process proceeds to step S208, and the correction content determined in step S204 (the correction content defined by the change amount Fctrl and the maximum change speed DFctrl1) is output. That is, the correction in the braking / driving force control is limited so that the change amount and the change speed in the correction in the braking / driving force control become the change amount Fctrl and the maximum change speed DFctrl1 obtained in step S204, respectively. Specifically, the change rate is limited by the maximum change rate DFctrl1, and the maximum value of the change amount at the time of correction is limited by the change amount Fctrl. In short, in this case, the normal braking / driving force control in the present invention is executed. Thereafter, this routine is once terminated.

  On the other hand, when the absolute value of the steering angle δ is equal to or smaller than the reference value A and the absolute value of the steering angular velocity Dδ is equal to or larger than the reference value B, the determination in step S207 is affirmative. The correction in the case of executing the braking / driving force control is limited based on the change amount Fctrl and the maximum change speed DFctrl3 obtained in step S201. That is, the above correction is limited so that the change amount and the change speed at the time of correction in the braking / driving force control become the change amount Fctrl and the maximum change speed DFctrl3, respectively. Specifically, as indicated by a solid line in the time chart of FIG. 10, the change rate at the time of correction is limited by the maximum change rate DFctrl3, and the maximum value of the change amount at the time of correction is limited by the change amount Fctrl. .

  The maximum change speed DFctrl3 does not give the driver a sense of incongruity when the steering turning operation and the returning operation are performed when the braking / driving force control according to the present invention is executed. In order to limit the change speed of the driving force or braking force in the braking / driving force control, it can be obtained in advance experimentally or empirically.

  When the correction in the case of executing the braking / driving force control is restricted in the above step S209, the process proceeds to the above-described step S208, and the correction content determined in step S209 (defined by the change amount Fctrl and the maximum change speed DFctrl3). Correction content) is output. That is, the braking / driving force control is executed based on the correction content limited in step S209. Thereafter, this routine is once terminated.

  As shown in the flowchart of FIG. 9, when the braking / driving force control of the present invention is executed, the control torque in the braking / driving force control, that is, the torque fluctuation state corresponding to the change in the driving force or the braking force is shown. This is shown in the time chart of FIG. As shown in the time chart of FIG. 11, in the braking / driving force control in the present invention shown in the flowchart of FIG. 9, the steering is cut within a short time, for example, when a lane change or a sharp steering wheel is performed. When the operation and the return operation are performed, it is determined whether or not the steering operation state continuously changes from the steering return operation to the cutting operation. When it is estimated that the steering operation state changes continuously from the steering return operation to the cutting operation, the control torque changing speed is slowed down during the steering return operation. Limited. That is, the upper limit value of the change amount and the change speed at the time of correction in the braking / driving force control is limited to be low. Therefore, as shown between the time t2 and the time t4 in the time chart of FIG. 11, the increase in the control torque is suppressed, and the control torque varies gently. Therefore, even in the braking / driving force control according to the present invention shown in the flowchart of FIG. 9, even when the steering turning operation and the returning operation are performed within a short period of time, for example, due to lane change or a sharp steering wheel, It can be avoided that the driver feels uncomfortable due to the fluctuation of the control torque as in the conventional control example.

  FIG. 12 is a flowchart for explaining still another example of control by the control device according to the present invention, and the routine shown in this flowchart is repeatedly executed every predetermined short time. In the flowchart of FIG. 12, the control details of each step from step S301 to step S308 are the same as the control details of each step from step S101 to step S108 in the flowchart of FIG. Detailed description is omitted.

  In the flowchart of FIG. 12, when an elapsed time T from the time when the steering operation is started in step S307 is obtained, the process proceeds to step S308, and whether or not a return operation is performed after the steering operation is performed. Is judged. As described above, this can be determined from the detected value of the steering angle δ.

  If a negative determination is made in step S308 because the steering turning operation or the returning operation has not been performed yet, or the steering returning operation has not been performed after the steering turning operation, the process proceeds to step S309. Then, the correction content determined in step S304 (the correction content defined by the change amount Fctrl and the maximum change speed DFctrl1) is output. That is, the above correction is limited so that the change amount and the change speed at the time of correction in the braking / driving force control become the change amount Fctrl and the maximum change speed DFctrl1 obtained in step S304, respectively. Specifically, the change rate is limited by the maximum change rate DFctrl1, and the maximum value of the change amount at the time of correction is limited by the change amount Fctrl. In short, in this case, the normal braking / driving force control in the present invention is executed. Thereafter, this routine is once terminated.

  On the other hand, if the return operation is performed after the steering turning operation and the determination in step S308 is affirmative, the process proceeds to step S310. Then, the elapsed time T obtained in step S307 is compared with the period Tb obtained in advance as the period of the sprung resonance frequency of the vehicle Ve in the state where the steering return operation is performed, and the elapsed time T is calculated. It is determined whether or not it is shorter than the period Tb.

  If the elapsed time T is longer than the period Tb and thus a negative determination is made in step S310, the process proceeds to step S309 described above, and the previous control is executed in the same manner. That is, normal braking / driving force control in the present invention is executed. Thereafter, this routine is once terminated. When the elapsed time T is longer than the period Tb, it can be determined that there is no possibility of torque fluctuation that resonates with the sprung resonance frequency of the vehicle Ve even if the return operation is performed after the steering turning operation. Therefore, in this case, normal braking / driving force control is executed.

  On the other hand, if the elapsed time T is shorter than the cycle Tb and the determination in step S310 is affirmative, the process proceeds to step S311 and the correction amount at the time of correction in the braking / driving force control of the present invention is determined. For example, filter processing using a low-pass filter is performed. That is, the speed of change of the driving force or braking force in the braking / driving force control of the present invention is limited. In this case, the cut-off frequency of the low-pass filter is set to a low value that is not more than half of the sprung resonance frequency of the vehicle Ve. By doing so, it is possible to reliably avoid the occurrence of torque fluctuations that resonate with the sprung resonance frequency of the vehicle Ve when the return operation is performed after the steering turning operation.

  When the correction in the case where the braking / driving force control is executed by the filtering process is restricted in the above step S311, the process proceeds to the above-described step S309, and the correction content filtered in the step S311 is output. That is, the braking / driving force control is executed based on the correction content limited in step S311. Thereafter, this routine is once terminated.

  As shown in the flowchart of FIG. 12, when the braking / driving force control of the present invention is executed, the control torque in the braking / driving force control, that is, the torque fluctuation state corresponding to the change in the driving force or the braking force is shown. This is shown in the time chart of FIG. As shown in the time chart of FIG. 13, in the braking / driving force control in the present invention shown in the flowchart of FIG. 12, the steering is cut within a short time, for example, when a lane change or a sharp steering wheel is performed. When an operation and a return operation are performed, a low-pass filter process is applied to the correction amount at the time of correction in the braking / driving force control of the present invention, so that the change speed of the control torque is reduced during the steering return operation. To be limited. That is, the upper limit value of the change amount and the change speed at the time of correction in the braking / driving force control is limited to be low. Therefore, as shown between the time t2 and the time t4 in the time chart of FIG. 13, the increase in the control torque is suppressed, and the control torque varies gently. Therefore, even in the braking / driving force control according to the present invention shown in the flowchart of FIG. 12, even when the steering turning operation and the returning operation are performed within a short time, for example, due to a lane change or a steep steering wheel, It can be avoided that the driver feels uncomfortable due to the fluctuation of the control torque as in the conventional control example.

  As described above, according to the control device for the vehicle Ve according to the present invention, the steering angle δ of the vehicle Ve that is increased or decreased by the driver's steering operation, and the lateral acceleration Gy of the vehicle Ve that is generated due to the steering operation or Based on the lateral jerk DGy, braking / driving force control for correcting and changing the driving force or the braking force when the vehicle Ve is turning is executed. In this case, the operation time and operation speed in the steering turning operation and the steering return operation, that is, the elapsed time T and the steering angular velocity Dδ are detected, and the control of the present invention is based on the operation elapsed time T and the steering angular velocity Dδ. A change speed at the time of correction in the driving force control is determined.

  Specifically, when the steering operation is performed, the braking / driving force is determined based on the elapsed time T and the steering angular velocity Dδ when the steering operation is performed during the return operation after the steering operation. The speed of change during correction in the control is limited. For example, as the elapsed time T is shorter or the steering angular speed Dδ is faster, the change speed at the time of correction in the braking / driving force control is limited to be slower.

  Alternatively, when a steering return operation is performed, the steering angle δ when the return operation is started and the steering angular velocity Dδ when the steering return operation is performed are detected, and the steering angle δ and the steering are detected. Based on the angular velocity Dδ, it is estimated whether or not the cutting operation is continuously performed after the steering returning operation. Then, when it is estimated that the cutting operation is continuously performed after the steering returning operation, the changing speed at the time of correction in the braking / driving force control of the present invention is limited. That is, the driving force or braking force corrected in the braking / driving force control is smoothly changed.

  Therefore, even if the steering turning operation and the returning operation are performed continuously or repeatedly due to, for example, a lane change or a sharp steering wheel, a change speed that does not give the driver a sense of incongruity is set. The braking / driving force control of the present invention can be executed. As a result, the braking / driving force control that stabilizes the vehicle behavior during turning and improves the turning performance of the vehicle Ve can be appropriately executed without causing the driver to feel uncomfortable or shocked.

  Here, the relationship between the above-described specific example and the present invention will be briefly described. Functional means for executing steps S105, S106, S107, S108, S205, S206, S207, S305, S306, S307, S308, and S310 are described. This corresponds to the “steering operation detecting means” in the present invention. The functional means for executing steps S110, S111, S209, and S311 corresponds to “braking / driving force setting means” in the present invention.

  In the specific example described above, as the vehicle Ve to be controlled in the present invention, a rear wheel drive vehicle that transmits the power of the driving force source 5 to the left and right rear wheels 3 and 4 to generate the driving force of the vehicle Ve. However, it may be a front wheel drive vehicle that transmits the power of the driving force source 5 to the left and right front wheels 1 and 2 to generate the driving force of the vehicle Ve. Alternatively, it may be a four-wheel drive vehicle in which the power of the driving force source 5 is distributed and transmitted to the front wheels 1, 2 and the rear wheels 3, 4, and the driving force of the vehicle Ve is generated by all these wheels.

  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 (3)

In a vehicle control device capable of executing braking / driving force control that stabilizes vehicle behavior during turning by correcting and changing driving force or braking force based on vehicle steering angle and lateral acceleration in the axle direction,
Steering operation detecting means for detecting an operation time and / or an operation speed in a steering turning operation in which the steering angle increases from 0 and a steering return operation in which the steering angle decreases toward 0;
When the steering turning operation and the steering return operation are performed, a change speed when changing the driving force or the braking force by the correction in the braking / driving force control based on the operation time or the operation speed is set. set to Rutotomoni, wherein in response to the operation time when the steering turning operation has been performed, the steering wheel return operation and a braking driving force setting means for limiting the rate of change in time to be performed A vehicle control device. Before Symbol steering operation detecting means when said steering wheel return operation is performed, on the basis on the operation speed during the steering angle and the steering wheel return operation of the steering wheel return operation start time, the steering wheel return operation and the steering Means for estimating that the cutting operation is performed continuously,
The braking / driving force setting means includes means for limiting the change speed when the steering return operation is performed when it is estimated that the steering return operation and the steering turning operation are continuously performed.
Control apparatus for a vehicle according to claim 1, wherein the this. Before SL braking-driving force setting means, a control for a vehicle according to claim 1 or 2, characterized in that it comprises means for limiting the pre-Symbol change speed by performing a filtering process to the control amount in the braking-driving force control apparatus.

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