JP2011105096A - Vehicle dynamics control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle dynamics control device for improving robust property against a traveling scene by suppressing the intervention of longitudinal acceleration control linked with a lateral motion in a scene where acceleration and deceleration is not necessary. <P>SOLUTION: The vehicle dynamics control device has a vehicle dynamics control arithmetic means 2 for controlling a wheel driving and braking torque actuator 3 or a brake lamp 4 based on driver input information or the like detected by an own vehicle information acquisition means 1, and the vehicle dynamics control arithmetic means 2 includes: a longitudinal acceleration command value arithmetic part 7 for calculating a longitudinal acceleration command value to be generated in a vehicle based on at least either steering operation information for generating a lateral motion in a vehicle or lateral motion information generated in the vehicle; and a longitudinal acceleration command value correction arithmetic part 8 for correcting the longitudinal acceleration command value based on the steering operation information and the lateral motion information. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle motion control device that controls the braking / driving force of each wheel so that the motion state of the vehicle is suitable.

  2. Description of the Related Art Conventionally, a system that performs deceleration when the lateral acceleration generated in a vehicle is larger than a set value from curve information of a navigation system and lateral acceleration during turning is known (for example, Patent Document 1). In such a device, the deceleration is created from the difference between the curve curvature and the lateral acceleration setting value, and the deceleration is not necessarily appropriate for the steering operation of the driver, and some drivers feel uncomfortable. It will be a certain deceleration.

  As a means for solving such a problem, an apparatus that performs acceleration / deceleration similar to that of a skill driver by acceleration / deceleration control based on lateral jerk generated by a driver operation has been proposed (for example, Patent Document 2 and Non-Patent Document). 1). In performing such control, a method has been proposed in which the lateral jerk is not directly detected, but the lateral jerk generated from the steering speed or the roll rate is estimated and acceleration / deceleration is performed (for example, Patent Document 3). As a result, the signal noise is smaller than when the lateral jerk actually generated is detected, and the necessary acceleration / deceleration control amount can be calculated at an earlier timing.

JP 2009-51487 A JP 2008-285066 A JP 2009-107447 A Automobile Engineering Society Proceedings Vol39, No. 3, 2008

  However, when the lateral jerk is estimated from the steering speed, etc., and the acceleration / deceleration control amount is calculated based on the estimated lateral jerk, acceleration / deceleration is performed in scenes where acceleration / deceleration is not necessarily required, such as staggered steering or switching when changing lanes. May occur.

  The present invention has been made in view of the above circumstances, and is a vehicle motion control capable of improving the robustness with respect to a traveling scene by suppressing the intervention of longitudinal acceleration control in a scene that does not require acceleration / deceleration. The object is to obtain a device.

  In order to achieve the above object, the present invention provides a host vehicle information acquisition unit that acquires host vehicle information including at least one of operation input information and vehicle motion information by a driver, and a host vehicle acquired by the host vehicle information acquisition unit. A vehicle motion control device that calculates longitudinal acceleration linked to the lateral motion of the vehicle based on the information, and the lateral motion linkage control computation means is the vehicle steering operation information acquired by the own vehicle information acquisition means, or the vehicle A longitudinal acceleration command value computing unit for computing a longitudinal acceleration command value for longitudinal acceleration generated in the vehicle based on at least one of the lateral motion information of the vehicle, and correcting the longitudinal acceleration command value based on the steering operation information and the lateral motion information A longitudinal acceleration command value correction calculation unit is included.

  According to the present invention, it is possible to suppress acceleration / deceleration control in a scene where acceleration / deceleration is unnecessary, such as wobbling steering or lane change.

1 is a system block diagram showing a configuration of a vehicle motion control device according to a first embodiment of the present invention. The system block diagram which shows the structure of the vehicle motion control calculating means by the 1st Embodiment of this invention. The system block diagram which shows the structure of the longitudinal acceleration command value calculating part by the 1st Embodiment of this invention. The system block diagram which shows the structure of the longitudinal acceleration command value correction | amendment calculating part by the 1st Embodiment of this invention. The conceptual diagram which shows the relationship between the steering angle by the 1st Embodiment of this invention, a yaw rate, and wobbling steering correction gain. The conceptual diagram which shows the relationship between the steering angle by the 1st Embodiment of this invention, a yaw rate, and wobbling steering correction gain. The conceptual diagram which shows the relationship between the steering angle and the longitudinal acceleration command value by the 1st Embodiment of this invention. The conceptual diagram which shows the relationship between the yaw rate by the 1st Embodiment of this invention, a yaw angle, and a lane change correction gain. The conceptual diagram which shows the relationship between the lateral acceleration estimated value by the 1st Embodiment of this invention, a lateral acceleration, and a lateral acceleration limit correction gain. The conceptual diagram which shows the relationship between the vertical gradient by the 1st Embodiment of this invention, gradient correction gain (deceleration), and gradient correction gain (acceleration). The conceptual diagram which shows the force which acts on the vehicle in the vertical gradient by the 1st Embodiment of this invention. The conceptual diagram which shows the relationship between the longitudinal acceleration, the steering angle, the yaw rate, and the gradient correction gain (deceleration) according to the first embodiment of the present invention. The conceptual diagram which shows the relationship between the lateral acceleration by the 1st Embodiment of this invention, a steering angle, and a rough road correction gain. The system block diagram which shows the structure of the target longitudinal acceleration calculating part by the 1st Embodiment of this invention. The conceptual diagram which shows the relationship between the steering angle by the 1st Embodiment of this invention, yaw rate, lateral acceleration, and a linear vehicle model correction | amendment gain. The system block diagram which shows the structure of the vehicle motion control apparatus by the 2nd Embodiment of this invention. The system block diagram which shows the structure of the longitudinal acceleration calculating means by the 2nd Embodiment of this invention. The system block diagram which shows the structure of the braking / driving torque control means by the 2nd Embodiment of this invention.

<First Embodiment>
Hereinafter, the configuration and operation of the vehicle motion control apparatus according to the first embodiment of the present invention will be described with reference to FIGS.

  Initially, the structure of the vehicle motion control apparatus by the 1st Embodiment of this invention is demonstrated using FIG. FIG. 1 is a system block diagram showing the configuration of the vehicle motion control device according to the first embodiment of the present invention.

  The vehicle motion control device of the present embodiment is mounted on a vehicle, and own vehicle information acquisition means 1 for acquiring the motion state (vehicle motion information) of the host vehicle and the operation amount (operation input information) by the driver; Vehicle motion control calculating means 2 for giving a control command to the braking / driving force actuator and the like, a wheel braking / driving torque actuator 3 for generating braking / driving torque on each wheel based on a command from the vehicle motion control calculating means 2, and the own vehicle And a brake lamp 4 for informing the rear vehicle of the deceleration.

  The own vehicle information acquisition means 1 receives the steering angle δ, the master cylinder pressure Pm, the accelerator pedal stroke amount, etc. as the driver input information 5, and the vehicle motion information 6 includes the vehicle body speed V and the vehicle body longitudinal acceleration. Gx, vehicle body lateral acceleration Gy, vehicle body yaw rate r, wheel speed Vw, etc. are input. Here, the vehicle speed V acquiring means may be a means for estimating from the wheel speed information of each wheel, or a means for directly measuring the vehicle speed using an external sensor or the like. Further, as the driver input information 5, a steering torque or a brake pedal stroke amount may be input. As the vehicle motion information, a longitudinal acceleration change rate Jx, a lateral acceleration change rate Jy, a roll rate q, and a side slip angle β may be input.

  The vehicle motion control calculating means 2 is the steering angle δ obtained by the own vehicle information obtaining means 1, the vehicle body speed V, the vehicle body longitudinal acceleration Gxact, the vehicle body lateral acceleration Gyact, the vehicle body yaw rate r, the wheel speed Vw [wheel] ( The wheel contains the FL (left front wheel), FR (right front wheel), RL (left rear wheel), and RR (right front wheel)), master cylinder pressure Pm, and accelerator pedal stroke amount. The drive control amounts of the wheel braking / driving torque actuator 3 and the brake lamp 4 are calculated.

  The wheel braking / driving force torque actuator 3 is an actuator that generates braking / driving torque for each wheel, and is a brake actuator that generates braking torque by pressing a brake pad or a shoe against the drum of each wheel. Even in an engine drive actuator that transmits engine torque generated by the engine to each wheel via a transmission to generate drive torque, a braking / driving motor that transmits motor torque to each wheel to generate braking / driving torque. It may be an actuator.

  Next, a control command calculation method for the wheel braking / driving torque actuator in the vehicle motion control calculation means 2 of the present invention will be described with reference to FIGS.

  FIG. 2 is a control block diagram of the vehicle motion control calculating means 2 according to the first embodiment of the present invention.

  As shown in FIG. 2, the vehicle motion control calculation means 2 includes a longitudinal acceleration command value calculation unit 7, a longitudinal acceleration command value correction calculation unit 8, a target braking / driving torque calculation unit 9, and an actuator drive command value calculation unit 10. .

  The longitudinal acceleration command value calculation unit 7 calculates a longitudinal acceleration command value linked to the lateral motion of the vehicle from the driver input information 5 and the vehicle motion information 6. FIG. 3 shows a control block diagram in the longitudinal acceleration command value calculation unit 7.

  As shown in FIG. 3, the longitudinal acceleration command value calculation unit 7 includes a lateral acceleration calculation unit 11 and a longitudinal acceleration calculation unit 12.

  The lateral acceleration calculation unit 11 calculates a lateral acceleration estimated value Gystr generated in the vehicle from the steering angle δ and the vehicle body speed V. Here, the lateral acceleration estimated value Gystr may be calculated using a vehicle model, or the map may be used to calculate the lateral acceleration estimated value Gystr with respect to the steering angle δ and the vehicle body speed V.

  The longitudinal acceleration calculation unit 12 calculates a longitudinal acceleration command value Gxtgt0 from the lateral acceleration estimated value Gystr. The longitudinal acceleration command value Gxtgt0 is given by the following equation (1). Here, the longitudinal acceleration command value Gxtgt0 is positive in the vehicle traveling direction, and is a positive value if acceleration, and a negative value if deceleration.

  In the above equation (1), | Gystr | is the absolute value of the lateral acceleration estimated value Gystr. Cxy is a gain, which is a value set by tuning according to the characteristics of the vehicle and the vehicle type. When the absolute value of the lateral acceleration estimated value Gystr increases with time from the equation (1), a negative longitudinal acceleration command value is calculated according to the increasing speed, and conversely, the absolute value of the lateral acceleration estimated value Gystr decreases with time. When doing so, a positive longitudinal acceleration command value is calculated according to the decreasing speed.

  The longitudinal acceleration command value correction calculation unit 8 corrects the longitudinal acceleration command value according to the traveling scene based on at least one of the driver input information 5 and the vehicle motion information 6. In the present embodiment, correction of the longitudinal acceleration command value according to the scene such as wobbling steering, lane change, turning near the lateral acceleration limit, traveling uphill, and acceleration will be described. FIG. 4 shows a control block diagram of the longitudinal acceleration command value correction calculation unit 8.

  As shown in FIG. 4, the longitudinal acceleration command value correction calculation unit 8 calculates a correction gain for correcting the absolute value of the longitudinal acceleration command value based on at least one of the driver input information 5 and the vehicle motion information 6. The final target longitudinal acceleration Gxtgt is calculated based on the calculation units 13 to 18, the correction gain calculated by these correction gain calculation units 13 to 18 and the longitudinal acceleration command value calculated by the longitudinal acceleration command value calculation unit 12. The target longitudinal acceleration calculation unit 19 is provided.

  The correction gain calculators 13 to 18 include the wobbling steering correction calculator 13, the lane change correction calculator 14, the lateral acceleration limit correction calculator 15, the gradient correction calculator 16, the rough road correction calculator 17, and the acceleration correction calculator 18. Become.

  The wobbling steering correction calculation unit 13 detects whether or not the wobbling steering by the driver has occurred. When the wobbling steering is detected, the wobbling steering correction gain is calculated. Here, when the wobbling steering with a small steering speed is performed, the variable acceleration itself of the absolute value | Gystr | of the lateral acceleration estimated value itself becomes a small value, so that a certain dead zone is given to the longitudinal acceleration command value Gxtgt0. By setting, acceleration / deceleration due to wobbling steering can be suppressed. Further, when the wobbling steering with a certain steering speed is performed to some extent, the detection and correction during the wobbling steering is performed from the relationship between the steering input by the driver and the response of the vehicle. For example, a wobbling steering correction gain may be created from the relationship between the steering angle and the yaw rate, and the wobbling steering may be corrected. As shown in FIG. 5, in the wobbling steering with a certain degree of steering speed, a phase shift occurs between the steering angle and the yaw rate generated in the vehicle. Therefore, in a region where the generated yaw rate is within the correction threshold value, in a region where the sign of the steering angle and the yaw rate and the respective change speeds, the steering speed and the sign of the yaw acceleration are the same, the wobbling steering correction gain is set to 1. In other areas, the wobbling steering correction gain is set to zero or a value smaller than one. This makes it possible to correct the absolute value of the longitudinal acceleration command value Gxtgt0 to zero or a value smaller than that before correction for wobbling steering with a large steering speed that causes the phase of the yaw rate to shift. By setting a certain dead zone, acceleration / deceleration due to wobbling steering can be suppressed. Thereby, only the wobbling steering can be suppressed without excessively suppressing the steering such as shown in FIG. Here, the method for suppressing the wobbling steering from the relationship between the steering angle and the yaw rate has been described. However, the information to be used is not limited to the steering angle and the yaw rate, and information such as a roll rate and a lateral acceleration may be used.

  The lane change correction calculation unit 14 calculates a lane change correction gain for correcting the longitudinal acceleration control amount at the time of lane change. When the lane change steering is performed, the longitudinal acceleration command value Gxtgt0 is calculated as shown in FIG. As described above, depending on the driver's steering, the deceleration of the longitudinal acceleration command value Gxtgt0 (C portion in FIG. 7) due to the reverse steering becomes larger than the longitudinal acceleration command value Gxtgt0 (A portion in FIG. 7) at the start of lane change. . When the deceleration of the C part of FIG. 7 is larger than the A part at the time of lane change, the driver may feel a strong sense of discomfort. On the other hand, on the acceleration side, the acceleration of the longitudinal acceleration command value Gxtgt0 (D portion of FIG. 7) by the steering immediately before the lane change is completed is larger than the longitudinal acceleration command value Gxtgt0 (B portion of FIG. 7) by the steering at the start of switching. The larger one is desirable. Therefore, correction is performed for the lane change-turning steering (B and C in FIG. 7). As a correction method, for example, the yaw angle of the vehicle is estimated from the generated yaw rate as shown in FIG. 8, and the lane change of the deceleration control is changed in the region where the yaw rate and the direction of the yaw angle coincide (E portion in FIG. 8). In a region where the correction gain (deceleration) is 1, and the two do not match (F portion in FIG. 8), the longitudinal acceleration command value Gxtgt0 at the time of switching can be corrected by setting the lane change gain to a value smaller than 1. it can. On the acceleration side, the lane change correction gain before switching (G portion in FIG. 8) is set to a value smaller than 1, and the lane change correction gain after switching (H portion in FIG. 8) is set to 1. The acceleration control at the start can be suppressed. Here, when estimating the yaw angle, using the yaw rate, the steering angle, or both, it is possible to prevent errors from accumulating in the estimated yaw angle by setting it to zero when it is determined that the vehicle is traveling straight. it can. Also, since an excessively large yaw angle does not occur in normal lane changes, an upper limit value is set for the yaw angle, and if a yaw angle greater than the upper limit value is generated, it is determined that the vehicle is driving in a curve and the lane change correction gain May be 1. Thereby, it is possible to prevent the longitudinal acceleration command value Gxtgt0 from being excessively corrected during traveling on a continuous curve such as an S-shaped curve. Here, the correction method using the yaw angle has been described. However, when a side slip angle acquisition unit or a side slip angle estimation unit of the vehicle body is provided, correction according to the side slip angle may be performed. For example, in a region where the sign of the side slip angle direction in which the steering direction is generated does not match, it may be determined that the vehicle is turned back and the lane change correction gain may be set to a value smaller than 1.

  The lateral acceleration limit correction calculation unit 15 calculates a lateral acceleration limit correction gain that corrects the longitudinal acceleration control amount during turning while the lateral acceleration is near the friction limit. As shown in FIG. 9 (a), the lateral acceleration actually generated in the vehicle changes nonlinearly with respect to steering as the friction limit approaches, and, for example, the change in lateral acceleration with respect to the steering angle decreases near the friction limit. . Therefore, when the lateral acceleration estimated value Gystr calculated by the lateral acceleration calculating unit 11 cannot accurately estimate the nonlinear degree of the lateral acceleration with respect to the steering, when the steering is performed in a state where the lateral acceleration is near the friction limit, There is a possibility of generating unnecessary longitudinal acceleration. Therefore, as shown in FIG. 9 (b), the lateral acceleration limit is determined from the degree of divergence between the lateral acceleration estimated value (broken line) and the actually generated lateral acceleration (solid line), and according to the degree of divergence. Decrease the lateral acceleration limit correction gain. Thereby, the longitudinal acceleration command value Gxtgt0 calculated when the lateral acceleration estimated value increases or decreases can be suppressed during a turn near the friction limit. Here, the determination of the lateral acceleration limit is not limited to the method based on the degree of deviation from the estimated lateral acceleration value described above, the friction limit is estimated, and the lateral acceleration limit correction gain is calculated from the relationship between the generated lateral acceleration and the friction limit. It may be changed. Alternatively, the lateral acceleration limit correction gain may be set to a small value in a region where the lateral acceleration is greater than a certain value, and the longitudinal acceleration control may not be performed in a region where the lateral acceleration is large.

  The gradient correction calculation unit 16 calculates a gradient correction gain that corrects the longitudinal acceleration control amount during gradient traveling. When the vehicle traveling road has a longitudinal gradient such as an uphill or downhill, excessive deceleration or acceleration may occur due to longitudinal acceleration control. Therefore, if the climbing slope is positive and the descending slope is negative, as shown in FIG. 10, in a region where there is a climbing slope (J portion in FIG. 10), a slope correction that is a slope correction gain on the deceleration side according to the climbing slope. The gain (deceleration) is set to a value smaller than 1, and the gradient correction gain (acceleration) that is the acceleration side gradient correction gain is set to a value larger than 1. Conversely, in a region having a downward gradient (see the region K in FIG. 10), the gradient correction gain (deceleration) is set to a value larger than 1, and the gradient correction gain (acceleration) is set to a value smaller than 1. Thereby, unnecessary deceleration on the climbing slope and acceleration on the descending slope can be suppressed. Here, as a method of estimating the longitudinal gradient, even if it is a method of estimating from the relationship between the driving torque generated in each wheel and the actual change of the vehicle speed, the detection result of the longitudinal acceleration sensor and the detection result of the longitudinal acceleration sensor Even a method of estimating the gradient from the difference may be a method of using longitudinal gradient information obtained by road-to-vehicle communication or a navigation system. Here, as a method for detecting drive torque, even if a means for directly detecting drive torque is provided, the drive torque is estimated from the engine torque and the shift position if the vehicle generates drive torque by the engine. Even if it is a method, as long as it is a vehicle which has generated drive torque with a motor, the method of estimating drive torque from the relation between motor torque and a reduction gear may be used. In addition, a method of detecting a pitch angle of the vehicle and estimating a longitudinal gradient from the pitch angle obtained thereby may be used. Further, the gradient correction gain may be changed from the yaw rate response to steering without using the longitudinal gradient. As shown in FIG. 11, when -Gx acceleration is generated in the vehicle, that is, when the vehicle is decelerating at the acceleration Gx, the acceleration Gx is decelerated by the force generated at the wheels shown in FIG. When the acceleration Gx is decelerated by the force generated at the center of gravity due to the longitudinal gradient shown in FIG. 11 (b), the load on the front and rear wheels is different, and in the case of FIG. 11 (a), the load on the front wheel increases. However, in the case of FIG. 11 (b), the load on the front wheel does not increase and the load on the rear wheel increases even with the same deceleration. Since the lateral force generated on the wheels varies depending on the load, the lateral forces generated on the front and rear wheels are different in FIGS. 11A and 11B even in the same deceleration state. As a result, as shown in FIG. 12, the yaw rate generated with respect to the steering changes to become the yaw rate (a) corresponding to FIG. 11 (a) and the yaw rate (b) corresponding to FIG. 11 (b). The gradient correction gain (deceleration) may be changed to a small value based on the above to correct the longitudinal gradient. Further, in the downward gradient, the relationships shown in FIGS. 11 and 12 are reversed, but the gradient gain (acceleration) can be changed from the change in the vehicle speed and the change in the yaw rate with respect to the steering as in the upward gradient. Further, when a single gradient is provided, the gradient correction gain may be changed according to the degree of the single gradient.

  The rough road correction calculation unit 17 calculates a rough road correction gain for correcting a control amount when traveling on a rough road surface (bad road). As shown in FIG. 13, when a relatively large lateral acceleration is generated even though the steering angle is small (the steering operation is not performed) as shown in FIG. Thus, the rough road correction gain may be changed to a value smaller than 1. In addition, as a method for determining a bad road, a method for determining from a relationship between lateral acceleration and yaw rate may be used, or a method for determining by comparing the wheel speed change of each wheel may be used.

  The acceleration correction calculation unit 18 calculates an acceleration correction gain that corrects only the acceleration control amount. In scenes where the absolute value of the lateral acceleration estimated value decreases, such as when a car escapes, the longitudinal acceleration command value Gxtgt0 obtained by the above equation (1) is positive and acceleration control is performed. The generation method differs depending on the driving method of the vehicle type such as front wheel drive, rear wheel drive, and four wheel drive. Due to the difference in the driving method, a suitable acceleration is different even in a scene that escapes from the same curve. There are also scenes that do not require acceleration, such as turning over when changing lanes. Therefore, when the longitudinal acceleration command value Gxtgt0 is positive, the acceleration correction calculation unit 18 performs correction according to the driving torque that can be generated by the front and rear wheels and the scene that requires acceleration. For example, when the acceleration correction gain is set to 1 in a four-wheel drive system that can generate an arbitrary drive torque on the front and rear wheels, if the vehicle is a rear-wheel drive vehicle, the front wheel drive torque is zero, and acceleration is performed only by the rear wheel drive torque. Since it is necessary, the acceleration correction gain is set to a value smaller than 1. As a result, it is possible to suppress a decrease in lateral force generated in the rear wheels due to an increase in driving torque by acceleration control. In addition, acceleration control is not performed when changing lanes, and acceleration control is performed only when escaping from the curve. When the lane change is determined, the acceleration correction gain is set to 1 only when escaping from the curve is determined. It may be zero in other scenes. Alternatively, the vehicle body speed at the time of entering the curve may be stored as the vehicle speed at which the vehicle enters the curve, and the acceleration correction gain may be set so that the vehicle body speed becomes the vehicle speed at which the vehicle enters the curve after exiting the curve.

  In the target longitudinal acceleration calculation unit 19, the driver input information 5, vehicle motion information 6, longitudinal acceleration initial value 12, wobbling steering correction calculation unit 13, lane change correction calculation unit 14, lateral acceleration limit correction calculation unit 15, gradient correction calculation The target longitudinal acceleration Gxtgt is calculated from signals from the unit 16, the rough road correction calculation unit 17, and the acceleration correction calculation unit 18. FIG. 14 shows a control block diagram in the target longitudinal acceleration calculation unit 19.

  As shown in FIG. 14, the target longitudinal acceleration calculation unit 19 includes a driver request acceleration calculation unit 20, a filter processing unit 21, a dead zone processing unit 22, an upper / lower limit processing unit 23, and a target longitudinal acceleration final value calculation unit 24. A target longitudinal acceleration Gxtgt is calculated.

  The driver request acceleration calculation unit 20 calculates a longitudinal acceleration request value Gxreq requested by the driver from the driver's accelerator pedal operation amount and brake pedal operation amount. For example, if it is an acceleration request, a longitudinal acceleration request value Gxreq corresponding to the accelerator pedal stroke amount is calculated. If it is a deceleration request, a longitudinal acceleration request value Gxreq corresponding to the brake pedal stroke amount and master cylinder pressure is calculated.

  The filter processing unit 21 adds the wobbling steering correction gain, the lane change correction gain, the lateral acceleration limit correction gain, the gradient correction gain, and the acceleration correction gain to the longitudinal acceleration command value Gxtgt0, and for the calculated value, Perform filtering. Here, in the case of performing the filtering process by the first-order delay, the time constant is set based on the response delay of the braking / driving torque actuator that generates acceleration based on the longitudinal acceleration command value Gxtgt0 and the operation feeling during acceleration control. Here, when the response delay of the actuator that generates the braking torque is different from that of the actuator that generates the driving torque, the time constant of the filter may be changed on the acceleration side and the deceleration side. Also, the time constant when the longitudinal acceleration command value Gxtgt0 increases may be different from the time constant when it decreases.

  The dead zone processing unit 22 performs dead zone processing on the filtered value Gxtgt_f. The dead zone setting method may be a value set in advance or a value set based on vehicle motion information. For example, in the case of a negative dead zone, the deceleration generated in the vehicle when the accelerator is off may be set as a negative dead zone. The size of the positive dead zone and the negative dead zone may be different.

  The upper / lower limit processing unit 23 performs upper / lower limit processing on the value Gxtgt_fd subjected to the dead band processing. The longitudinal acceleration command value upper limit value, the longitudinal acceleration command value lower limit value, or both are set according to the vehicle speed, road surface condition, wheel braking / driving force torque actuator 3, etc., and the longitudinal acceleration command value is the longitudinal acceleration command value. When the longitudinal acceleration command value is larger than the upper limit value, the longitudinal acceleration command value upper limit value is set as the longitudinal acceleration command value. When the longitudinal acceleration command value is smaller than the longitudinal acceleration command value upper limit value, the longitudinal acceleration command value lower limit value is set as the longitudinal acceleration command value. And Here, as a setting method of the longitudinal acceleration command value upper limit value and the longitudinal acceleration command value lower limit value, for example, when the wheel braking / driving force torque actuator 3 is only a brake, only the deceleration is controlled. Set the command value upper limit to zero. Further, when a means for obtaining or estimating a steerability securing limit in consideration of a response of a yaw rate or lateral acceleration with respect to steering is provided, the longitudinal acceleration command value upper limit value or the longitudinal acceleration command value depending on the steerability securing limit Set the lower limit or both. Further, the longitudinal acceleration command value upper limit value, the longitudinal acceleration command value lower limit value, or both are set according to the steering performance securing limit so that the yaw rate generated at the vehicle body speed does not become excessive.

  The target longitudinal acceleration final value calculation unit 24 calculates the final target longitudinal acceleration Gxtgt from the longitudinal acceleration request value Gxreq and the upper and lower limit processing value Gxtgt_fdl. As the calculation method, when the sign of the longitudinal acceleration request value Gxreq and the upper and lower limit processing value Gxtgt_fdl are different, the longitudinal acceleration request value Gxreq is set as the target longitudinal acceleration Gxtgt, and the sign of the longitudinal acceleration request value Gxreq and the upper and lower limit processing value Gxtgt_fdl is the same The value with the larger absolute value of both may be used as the target longitudinal acceleration Gxtgt. When the longitudinal acceleration request value Gxreq is zero, the upper / lower limit processing value Gxtgt_fdl is set as the target longitudinal acceleration Gxtgt, and the longitudinal acceleration request value Gxreq becomes a value other than zero during acceleration control using the upper / lower limit processing value Gxtgt_fdl. The target longitudinal acceleration Gxtgt may be a value obtained by adding the longitudinal acceleration request value Gxreq to the upper / lower limit processing value Gxtgt_fdl.

  The target braking / driving torque calculation unit 9 calculates a target braking / driving torque Tw_tgt [wheel] to be generated for each wheel from the target longitudinal acceleration Gxtgt.

  The actuator drive command value calculation unit 10 calculates a required actuator drive control command value according to the target braking / driving torque Tw_tgt [wheel]. For example, when the wheel braking / driving torque actuator is a motor, the motor drive command value is calculated so as to generate the target braking / driving torque Tw_tgt [wheel]. Further, when the target braking / driving torque Tw_tgt [wheel] at this time is negative, that is, when braking torque is generated, a brake lamp driving command is calculated so that the brake lamp is turned on according to the deceleration to be generated. For example, when the deceleration to be generated is very small, the brake lamp may not be turned on, and the brake lamp may be turned on only when a deceleration greater than a predetermined value is generated.

  In the longitudinal acceleration command value correction calculation unit 7 of the present embodiment, the wobbling steering correction calculation unit 13, the lane change correction calculation unit 14, the lateral acceleration limit correction calculation unit 15, the gradient correction calculation unit 16, and the rough road correction calculation unit 17 are provided. Although the configuration having the acceleration correction calculation unit 18 has been described, there may be other correction methods.

  For example, it has a linear vehicle model correction calculation unit that determines whether or not the yaw rate and lateral acceleration generated for steering are in a relationship represented by a linear vehicle model, and correction is performed from the relationship between steering, yaw rate, and lateral acceleration. You may go. As shown in FIG. 15, if the actual yaw rate and the actual lateral acceleration generated with respect to the steering are within the response range similar to the linear yaw rate and the linear lateral acceleration estimated by the linear vehicle model, the linear vehicle The model correction gain may be 1, and the linear vehicle model correction gain may be a value smaller than 1 under other conditions. Thereby, for example, in the above-described wobble steering or rough road, the difference between the linear yaw rate and the actual yaw rate, or the linear lateral acceleration and the actual lateral acceleration becomes large, so that the longitudinal acceleration command value can be suppressed. Further, it is possible to suppress the longitudinal acceleration command value in a scene such as when the road surface friction is low or when driving near the limit acceleration.

  In addition, a driving skill correction calculation unit that estimates the driving skill of the driver may be provided, and correction may be performed according to the driving skill of the driver. Even if the driver runs the same curve at the same speed, there are drivers that perform a sharp steering operation just before the curve and drivers that perform a smooth and smooth steering operation immediately before the curve. Some drivers perform jerky driving that repeats switchback. The driving skill correction calculation unit estimates the driver's driving skill from the steering operation of the driver and the generated lateral acceleration and longitudinal acceleration, and for drivers who have abrupt steering or jerky steering from normal driving. The driving skill correction gain is set to a value smaller than 1, and the driving skill correction gain is set to 1 for a driver who performs smooth steering.

  In addition, when a switch for selecting a control mode is provided by the driver, a control mode correction calculation unit that performs correction according to the selected control mode may be provided, and correction may be performed according to the control mode selected by the driver. For example, when there are two control modes, “normal mode” and “sport mode”, the control mode correction gain in “normal mode” is set to 1, and the control mode correction gain in “sport mode” is larger than 1. It may be a value.

  In addition, a vehicle body speed correction calculation unit that corrects the control gain according to the vehicle body speed may be provided, and the correction may be performed according to the vehicle body speed. For example, the deceleration correction gain is set to a value smaller than 1 in a region where the vehicle body speed is very small and deceleration control is not necessary. Conversely, in a region where the vehicle body speed is very high and the yaw rate generated by the deceleration control is excessive, the deceleration correction gain is set to a value smaller than 1.

  In the present embodiment, the correction gain is calculated by each correction calculation unit. However, not only the gain but also the filter time constant of the filter processing unit 21, the dead band of the dead band processing unit 22, and before and after the upper and lower limit processing unit 23. The acceleration command value upper limit value and the longitudinal acceleration command value lower limit value may be corrected simultaneously.

  For example, when staggered steering or a rough road is detected, either the time constant of the filter, the dead zone threshold value, or both may be corrected to a large value. Further, depending on the driving skill of the driver, for a driver with a lot of jerky steering, either the filter time constant or the dead zone threshold value, or both may be corrected to a large value. Further, in the “sport mode”, either the time constant of the filter, the dead zone threshold value, or both may be corrected to a smaller value in the “sport mode” than in the “normal mode”.

  As described above, in the present invention, by adding feedback based on vehicle motion information to the longitudinal acceleration command value created based on the conventional steering angle, the absolute value of the longitudinal acceleration command value is determined according to the driving scene. The value can be corrected to zero or smaller than before correction. This makes it possible to improve the robustness to the driving scene while taking advantage of the fact that the acceleration / deceleration command value for either acceleration or deceleration can be calculated and created with a small amount of signal noise and can be calculated at an early timing. Intervention of longitudinal acceleration control in unnecessary scenes can be suppressed.

  Therefore, compared with a case where acceleration / deceleration is suppressed by simply increasing the intervention threshold of acceleration / deceleration control, for example, in the present invention, it is possible to prevent a response from being delayed in a scene that requires acceleration / deceleration such as when entering a curve, It is possible to effectively prevent a sense of incongruity from occurring.

<Second Embodiment>
Hereinafter, the configuration and operation of the vehicle motion control apparatus according to the second embodiment of the present invention will be described with reference to FIGS.

  Initially, the structure of the vehicle motion control apparatus by the 2nd Embodiment of this invention is demonstrated using FIG.

  FIG. 16 is a system block diagram showing the configuration of the vehicle motion control device according to the second embodiment of the present invention.

  The vehicle motion control apparatus according to the present embodiment is mounted on a vehicle, and includes a host vehicle information acquisition unit 1 that acquires a motion state of the host vehicle and an operation amount by a driver, and a longitudinal acceleration calculation unit 25 that creates a target longitudinal acceleration. And a braking / driving torque control means 26 for controlling the braking / driving torque of each wheel, a wheel braking torque actuator 27 for generating a braking torque for each wheel based on a command from the braking / driving torque control means 26, and driving to each wheel. A wheel drive torque actuator 28 for generating torque and a brake lamp 4 for informing the vehicle behind the deceleration of the host vehicle are provided.

  Since the own vehicle information acquisition unit 1 and the brake lamp 4 are the same as those in the first embodiment, detailed description thereof is omitted. The wheel braking torque actuator 27 is an actuator that generates a braking torque for each wheel. Even if the wheel braking torque actuator 27 is a brake actuator that generates a braking torque by pressing a brake pad or a shoe against a drum of each wheel, a motor A motor actuator that transmits torque to each wheel to generate braking torque may be used.

  The wheel drive torque actuator 28 is an actuator that generates a drive torque for each wheel, and is an engine drive actuator that generates the drive torque by transmitting the engine torque generated by the engine to each wheel via the transmission. A motor actuator that transmits motor torque to each wheel to generate drive torque may be used.

  The longitudinal acceleration calculation means 25 calculates a target longitudinal acceleration linked to the lateral movement of the vehicle from the driver input information 5 and the vehicle movement information 6. FIG. 16 shows a control block diagram in the longitudinal acceleration calculating means 25.

  As shown in FIG. 17, the longitudinal acceleration calculation means 25 includes a longitudinal acceleration command value calculation unit 7 and a longitudinal acceleration command value correction calculation unit 8. Here, since the details of the longitudinal acceleration command value calculation unit 7 and the longitudinal acceleration command value correction calculation unit 8 are the same as those in the first embodiment, detailed description thereof will be omitted.

  The braking / driving torque control means 26 calculates drive control command values for the wheel braking torque actuator 27, the wheel driving torque actuator 28, and the brake lamp 4 from the target longitudinal acceleration from the longitudinal acceleration calculating means 25. Here, when the driver input information 5 and the vehicle motion information 6 are input, higher-accuracy braking / driving torque control is possible. FIG. 17 shows a control block diagram of the braking / driving torque control means 26.

  As shown in FIG. 18, the braking / driving torque control means 26 includes a target braking / driving torque calculation unit 9, a braking torque actuator drive command value calculation unit 29, a drive torque actuator drive command value calculation unit 30, and a brake lamp drive command value calculation unit. 31. Here, the details of the target braking / driving torque calculation unit 9 are the same as those in the first embodiment described above, and thus detailed description thereof is omitted.

  The braking torque actuator drive command value calculation unit 29 calculates a drive control command value for the wheel braking torque actuator 27 according to the target braking torque. The drive torque actuator drive command value calculation unit 30 calculates a drive control command value for the wheel braking torque actuator 28 according to the target drive torque. The brake lamp drive command value calculation unit 31 calculates a brake lamp drive control command value according to the target braking torque. As described above, the calculation of the target longitudinal acceleration and the calculation of the braking / driving torque control do not necessarily have to be performed by the same calculator, but may be configured such that they are different from each other and communicate with each other by communication.

DESCRIPTION OF SYMBOLS 1 ... Own vehicle information acquisition means 2 ... Vehicle motion control calculating means 3 ... Wheel braking drive torque actuator 4 ... Brake lamp 5 ... Driver input information 6 ... Vehicle motion information 7 ... Longitudinal acceleration command value calculating part 8 ... Longitudinal acceleration command value correction Calculation unit 9 ... Target braking / driving torque calculation unit 10 ... Actuator drive command value calculation unit 11 ... Lateral acceleration calculation unit 12 ... Longitudinal acceleration calculation unit 13 ... Fluctuation steering correction calculation unit 14 ... Lane change correction calculation unit 15 ... Lateral acceleration limit correction Calculation unit 16 ... Gradient correction calculation unit 17 ... Rough road correction calculation unit 18 ... Acceleration correction calculation unit 19 ... Target longitudinal acceleration calculation unit 20 ... Driver request acceleration calculation unit 21 ... Filter processing unit 22 ... Dead zone processing unit 23 ... Upper and lower limit processing Unit 24 ... target longitudinal acceleration final value calculation unit 25 ... longitudinal acceleration calculation means 26 ... braking / driving torque control means 27 ... wheel braking torque actuator 28 Wheel driving torque actuator 29 ... braking torque actuator drive command value calculation unit 30 ... driving torque actuator drive command value calculation unit 31 ... brake lamp drive command value calculation unit

Claims (13)

A vehicle motion control device that controls the longitudinal acceleration of a vehicle in conjunction with the lateral motion of the vehicle,
Own vehicle information acquisition means for acquiring own vehicle information including driver input information and vehicle movement information of operation by the driver;
Vehicle motion control calculating means for calculating the longitudinal acceleration linked to the lateral movement of the vehicle based on the own vehicle information acquired by the own vehicle information acquiring means,
The vehicle motion control calculation means includes:
Longitudinal acceleration command value for calculating the longitudinal acceleration command value of the longitudinal acceleration generated in the vehicle based on at least one of the steering operation information included in the driver input information or the lateral movement information included in the vehicle movement information An arithmetic unit;
A longitudinal acceleration command value correction calculation unit for correcting the longitudinal acceleration command value based on the steering operation information and the lateral motion information;
A vehicle motion control device comprising: The longitudinal acceleration command value correction calculation unit is
A correction gain calculator for calculating a correction gain for correcting the absolute value of the longitudinal acceleration command value based on the steering operation information and the lateral motion information;
A target longitudinal acceleration calculator for calculating a target longitudinal acceleration based on the correction gain calculated by the correction gain calculator and the longitudinal acceleration command value calculated by the longitudinal acceleration command value calculator;
The vehicle motion control device according to claim 1, comprising: The correction gain calculation unit includes a wobbling steering correction calculation unit that corrects a longitudinal acceleration command value during wobbling steering of the vehicle.
When the wobbling steering correction calculating unit determines whether or not the wobbling steering of the vehicle is performed based on the steering operation information and the lateral movement information, and determines that the wobbling steering of the vehicle is performed 3. The vehicle motion control device according to claim 2, wherein a wobbling steering correction gain for correcting the absolute value of the longitudinal acceleration command value to zero or a value smaller than that before correction is calculated. The correction gain calculation unit includes a lane change correction calculation unit that corrects a longitudinal acceleration command value at the time of lane change of the vehicle,
When the lane change correction calculation unit determines whether or not the lane change of the vehicle is performed based on the steering operation information and the lateral movement information, and determines that the lane change of the vehicle is performed The vehicle motion control device according to claim 2, wherein a lane change correction gain for correcting the absolute value of the longitudinal acceleration command value to zero or a value smaller than that before correction is calculated. The correction gain calculation unit includes a lateral acceleration limit correction calculation unit that corrects a longitudinal acceleration command value for turning while the lateral acceleration of the vehicle is near a friction limit,
The lateral acceleration limit correction calculation unit determines whether the lateral acceleration of the vehicle has reached a vicinity of a friction limit based on the steering operation information and the lateral motion information, and the lateral acceleration of the vehicle is determined to be the friction limit. 3. A lateral acceleration limit correction gain for correcting the absolute value of the longitudinal acceleration command value to zero or a smaller value than before correction when it is determined that the vehicle has reached the vicinity. The vehicle motion control device described in 1. The correction gain calculation unit includes a gradient correction calculation unit that corrects a longitudinal acceleration command value during gradient traveling,
The gradient correction calculation unit detects the gradient and the gradient degree of the road on which the vehicle travels, and when the climb gradient is detected, the absolute value of the longitudinal acceleration command value is zero based on the gradient degree of the climb slope Correct to a smaller value than before,
The slope correction gain for correcting the absolute value of the longitudinal acceleration command value to a value larger than that before the correction is calculated based on the slope degree of the downward slope when a downward slope is detected. The vehicle motion control device described in 1. The correction gain calculation unit has a rough road correction calculation unit that corrects the longitudinal acceleration command value when traveling on rough roads,
The rough road correction calculation unit determines whether the vehicle is traveling on a rough road based on the steering operation information and the lateral movement information, and determines that the vehicle is traveling on a rough road. 3. The vehicle motion control device according to claim 2, wherein a rough road correction gain for correcting the absolute value of the longitudinal acceleration command value to zero or a value smaller than that before correction is calculated. The correction gain calculation unit includes an acceleration correction calculation unit that corrects only the acceleration control amount of the longitudinal acceleration command value.
The acceleration correction calculation unit determines whether or not the vehicle needs to be accelerated based on the steering operation information and the lateral motion information, and when determining that the vehicle does not need to be accelerated, The vehicle motion control device according to claim 2, wherein an acceleration correction gain for correcting the absolute value of the longitudinal acceleration command value to zero or a value smaller than that before correction is calculated. The correction gain calculation unit includes a linear vehicle model correction calculation unit that corrects the longitudinal acceleration command value according to whether or not at least one of the yaw rate and the lateral acceleration with respect to the steering angle is represented by the linear vehicle model. Have
The linear vehicle model correction calculation unit determines whether or not at least one of the yaw rate and the lateral acceleration with respect to the steering angle has a relationship represented by the linear vehicle model based on preset data. When it is determined that the relationship is not represented by a vehicle model, a linear vehicle model correction gain that corrects the absolute value of the longitudinal acceleration command value to zero or a value smaller than before correction is calculated. The vehicle motion control device according to claim 2. The correction gain calculator has a driving skill correction calculator that corrects the longitudinal acceleration command value according to the driving skill of the driver,
The driving skill correction calculating unit determines the driving skill of the driver based on at least one of a driver's steering operation, a lateral acceleration and a longitudinal acceleration generated in the vehicle by the steering operation, and does not satisfy a preset criterion. The driving skill correction gain for correcting the absolute value of the longitudinal acceleration command value to zero or a value smaller than that before correction is calculated when it is determined that the driving skill is determined. Vehicle motion control device. The correction gain calculation unit includes a control mode correction calculation unit that corrects the longitudinal acceleration command value according to a control mode selected by a driver from a plurality of preset control modes.
The control mode correction calculation unit is a control that corrects the absolute value of the longitudinal acceleration command value to a value larger than that before correction when the sport mode is selected from at least two control modes of the normal mode and the sport mode. The vehicle motion control apparatus according to claim 2, wherein a mode correction gain is calculated. The correction gain calculation unit includes a vehicle body speed correction calculation unit that corrects the longitudinal acceleration command value according to the vehicle body speed,
The vehicle body speed correction calculation unit corrects the absolute value of the longitudinal acceleration command value to a smaller value than before the correction in an area where the vehicle speed is so low that deceleration control is unnecessary, so that the yaw rate generated by the deceleration control becomes excessive. The vehicle motion control device according to claim 2, wherein a deceleration correction gain for correcting the absolute value of the longitudinal acceleration command value to a value smaller than that before correction is calculated in a region where the vehicle body speed is high. The steering operation information includes at least one of a steering angle and a steering angular velocity,
The lateral motion information includes at least one of a lateral acceleration generated in the vehicle, a yaw rate generated in the vehicle, a roll rate generated in the vehicle, a yaw angle of the vehicle, and a side slip angle of the vehicle. The vehicle motion control device according to any one of claims 1 to 12.

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