JP2018192980A - Vehicle control method and vehicle control device - Google Patents

Abstract

To provide a vehicle control method by which control for restricting the phenomenon in which an own vehicle moves in a lateral direction due to an inclination of a road surface during traveling in an inclined lane can be performed in a short time, compared to a case in which single-flow managing control is performed when a cumulated value of steering torque has become equal to or higher than a threshold value as in a conventional manner.SOLUTION: A vehicle control method in which a vehicle is controlled using a vehicle control device with a sensor and a control device mounted in an own vehicle comprises: performing control in which a traveling trajectory of the own vehicle is returned to a target trajectory by controlling an amount of steering with a first amount of steering, the amount of steering being a lateral deviation from a traffic lane, in which the own vehicle is traveling, with respect to a lapse of time; estimating, as an amount of change in inclination, a change in inclination of a road surface on which the own vehicle is traveling, by using data detected by the sensor; and setting the amount of steering to a second amount of steering, which is larger than the first amount of steering, in a case where the amount of change in inclination is equal to or greater than a predetermined value.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a vehicle control method and a vehicle control device.

  A steering motor is provided, and when the vehicle is in a straight traveling state, control for applying assist torque to the steering system is performed by controlling drive power related to the motor based on vehicle information including steering torque and steering angle. A vehicle steering device is known (see, for example, Patent Document 1). The vehicle steering apparatus described in Patent Literature 1 calculates a torque integrated value obtained by integrating the steering torque, and when the torque integrated value is equal to or greater than a threshold value, the single-flow correspondence of the drive power related to the electric motor is applied so as to cancel the vehicle single-flow phenomenon. Take control.

JP 2015-37932 A

  However, since the vehicle undergoes a single flow and the single flow correspondence control is started when the integrated value of the steering torque exceeds a threshold value, there is a problem that it takes time until the single flow correspondence control is started after the vehicle causes a single flow. is there.

  The problem to be solved by the present invention is that control that suppresses the phenomenon that the host vehicle moves in the lateral direction due to the inclination of the road surface while traveling on a sloping lane, the integrated value of the steering torque exceeds the threshold value as in the conventional case. It is to provide a vehicle control method or a vehicle control device that can be executed in a short time compared to the case where the single flow correspondence control is executed at that time.

  The present invention performs control for controlling the steering amount with respect to the time lapse of the deviation in the lateral direction with respect to the traveling lane of the own vehicle with the first steering amount, and returning the traveling locus of the own vehicle to the target locus, Using the detected data, the change in the inclination of the traveling road surface of the host vehicle is predicted as the amount of change in inclination. If the amount of change in inclination is greater than or equal to a predetermined value, the steering amount is set to a second steering amount that is larger than the first steering amount. The above problem is solved by setting.

  The present invention predicts that the amount of change in inclination will increase, and since the setting of the steering amount with respect to the time lapse of the deviation in the lateral direction is increased in advance, it is possible to eliminate the deviation in the lateral direction from the target locus. Control time can be suppressed.

FIG. 1 is a block diagram of a vehicle control system having a vehicle control apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating the relationship between the cant angle of the road surface and the vehicle state. FIG. 3 is a flowchart showing a control procedure of steering control processing executed by the vehicle control system according to the present embodiment. FIG. 4 is a block diagram of steering control executed by the control device in the vehicle control system according to the present embodiment. FIG. 5 is a diagram illustrating a positional relationship between the host vehicle and another vehicle in the vehicle control system according to the present embodiment. FIG. 6 is a graph for explaining the relationship between the cant change amount and the gain setting. FIG. 7 is a graph showing the steering amount characteristic. Figure 8 is a cant angle (theta), cant variation (dθ / dt), the lateral displacement ([Delta] y), transverse velocity (Vy), and a graph showing the characteristics of the integral increase gain _{(k i).}

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case where the vehicle control device according to the present invention is applied to a vehicle control system of a vehicle will be described as an example.

  FIG. 1 is a block diagram of a vehicle control system 1000 having a vehicle control apparatus 100 according to an embodiment of the present invention. The vehicle control system of this embodiment includes a steering unit 1, a steering wheel 2, wheels 3 and 4, and a vehicle control device 100. The vehicle control device 100 according to the present embodiment controls the steering of the wheels 3 and 4 according to the operation of the steering wheel 2.

  The steering unit 1 includes a shaft 11, a motor 12, a steering angle sensor 13, a torque sensor 14, and a gear (not shown). The shaft 11 is connected to the left and right drive wheels. A rack and pinion type steering gear is used as the gear, and the front wheels 3 and 4 are steered according to the rotation of the shaft 11.

  The motor 12 is, for example, a brushless motor, and the output shaft of the motor 12 is connected to the rack gear via a speed reducer to steer the front wheels 3 and 4 with respect to the rack in accordance with a control command from the control device 30. The steering torque is output. Further, the motor 12 operates to give a steering amount in accordance with a control command from the control device 30 and outputs a steering torque. The steering amount is given to the steering unit 1 in order to promote steering for suppressing disturbance. For example, when disturbances such as crosswinds and road slopes are input and affect the behavior of the vehicle, steering torque is applied to the steering to suppress the disturbances in the direction of crosswinds or downhills. The steering operation is suppressed. Such a single flow control of a vehicle by disturbance is employed in, for example, a lane departure prevention support system. When the steering mechanism of the steering unit 1 can be electronically controlled, the motor 3 may be installed so as to generate a steering amount directly with respect to the steering mechanism. When the steering unit 1 is configured by electrohydraulic power steering, the motor 3 supplies power to the electric pump. The motor 12 corresponds to the “actuator” of the present invention.

  The steering angle sensor 13 detects the rotation angle of the motor 12 to calculate the steering angle (steering angle) of the front wheels 3 and 4. There is a correlation between the rotation angle of the motor 12 and the steering angle of the front wheels 3 and 4. The steering angle sensor 13 calculates a steering angle corresponding to the motor rotation angle while referring to a map showing a correspondence relationship between the rotation angle of the motor 12 and the steering angle of the front wheels 3 and 4, so that the front wheels 3 and 4 Detect the rudder angle.

  The torque sensor 14 is provided in a connecting mechanism that connects the steering wheel 2 and the steering unit 1, and detects a steering torque corresponding to the steering amount of the steering wheel 2 of the driver. The steering angle sensor 13 and the torque sensor 14 output detection values to the control device 30.

  The camera 20 is an imaging device that captures a state in front of the vehicle. The camera 20 operates while the vehicle is running and is used as a sensor that detects the surroundings of the vehicle. The camera 20 outputs captured image data to the control device 30. The sensor that detects the front of the vehicle is not limited to the camera 20, but may be a radar, a sonar, or the like. Moreover, not only the camera 20 but the own vehicle may detect the state ahead of the own vehicle by acquiring the information of other vehicles using inter-vehicle communication, for example.

  The vehicle control device 100 includes a motor 12, a steering angle sensor 13, a torque sensor 14, a vehicle state sensor 15, a camera 20, and a control device 30. Each component of the vehicle control device 100 is connected by a CAN (Controller Area Network) or other in-vehicle LAN in order to exchange information with each other. The vehicle control device 100 executes steering control based on detection data input from the steering angle sensor 13 and the torque sensor 14. When there is a deviation between the steering amount of the steering wheel 2 and the actual steering angle detected by the steering angle sensor 13, the vehicle control device 100 determines that the steering angle detected by the steering angle sensor 13 is Then, the control steering amount that matches the steering amount of the steering wheel 2 is calculated, and a control command value corresponding to the control steering amount is output to the motor 12.

  The vehicle state sensor 15 is a sensor that detects the current state of the vehicle, and is a sensor such as a vehicle speed sensor, an acceleration sensor, or a yaw rate sensor. In the present embodiment, the vehicle state sensor 15 is used to predict the inclination angle of the traveling road surface of the host vehicle.

  The control device 30 of the vehicle control device 100 of the present embodiment includes a ROM 12 that stores a vehicle control program, and an operation circuit that functions as the vehicle control device 100 of the present embodiment by executing the program stored in the ROM 12. And a RAM 13 that functions as an accessible storage device.

  The vehicle control program according to the present embodiment is a program that executes a control procedure for detecting a state around the vehicle, performing steering control of the vehicle according to the detection result, and generating a lateral movement of the vehicle. . This program is executed by the control device 30 of the vehicle control device 100 of the present embodiment.

  The control device 30 of the vehicle control device 100 according to the present embodiment includes an ambient condition detection function, a tilt change prediction function that predicts a tilt change of a traveling road surface, a calculation function that calculates a control command value for giving a steering amount, and steering A function for executing control processing is provided. Each process described above is executed by cooperation of software for realizing each process and the hardware described above.

  Here, the relationship between the cant angle of the road surface and the state of the vehicle will be described with reference to FIG. FIG. 2 is a diagram illustrating the relationship between the cant angle of the road surface and the vehicle state. (A) to (c) are arranged in time series, and change in the order of (a), (b), and (c). The cant angle is an angle between the horizontal plane and the road surface. The center axis D is an axis in the normal direction with respect to the road surface, and is a lane center axis.

  As shown in FIG. 2 (a), it is assumed that the vehicle is traveling on a road surface that is inclined downward to the left. It is assumed that the road surface changes from a left-down slope to a right-down slope, and the vehicle state changes from the state shown in FIG. 2A to the state shown in FIG. As the cant angle changes, the slope of the center axis D of the road surface changes from left to right. When the inclination of the center axis D of the road surface changes from left to right, a force (corresponding to the arrow F in FIG. 2C) is applied to the tire, and the vehicle is swung in a direction in which the cant angle changes. That is, a lateral force is applied to the vehicle and the steer is shaken.

  Next, the lane keeping control when the cant angle changes as shown in FIG. 2 will be described. In the lane keeping control, when the lateral position of the host vehicle deviates from the target track, the steering amount is controlled so that the travel track of the host vehicle is returned to the target track. The lateral direction is a direction perpendicular to the traveling direction of the host vehicle on the road surface. For example, when the vehicle is traveling in a straight lane in an automatic driving mode and a lateral force is applied to the vehicle due to a disturbance, the vehicle slides in the lateral direction, so the lateral position of the vehicle is the target Deviation occurs from the locus. The automatic driving system applies a steering force that returns the traveling locus of the host vehicle to the target direction with respect to the lateral deviation with respect to the target locus. At this time, the control steering amount for applying the steering force is determined by the gain setting with respect to the time lapse of the deviation, and the steering amount increases as the deviation increases. As a result, the host vehicle can travel following the target locus.

  Under such lane keeping control, when the cant angle changes as shown in FIG. 2, it is detected that the vehicle is actually moving in the lateral direction by receiving the lateral force. Then, the steering amount is controlled so that the traveling locus of the host vehicle is returned to the target locus. That is, the control of the steering amount by the vehicle maintenance control is executed when the vehicle is in the state shown in FIG. However, even if the gain is increased so as to reduce the deviation after the vehicle has actually moved in the lateral direction, the deviation of the own vehicle with respect to the target trajectory increases due to a delay in feedback control or the like. The vehicle control apparatus 100 according to the present embodiment performs control such that a change in inclination is predicted and the followability to the target locus is improved by a vehicle control method described below.

  FIG. 3 is a flowchart showing a control procedure of steering control processing executed by the vehicle control system 1000 according to the present embodiment. The control flow shown in FIG. 3 is executed under lane keeping control, and is repeatedly executed at a predetermined cycle.

  In step S <b> 1, the control device 30 acquires a captured image obtained by capturing the front of the host vehicle from the camera 20, and acquires current steering angle data from the steering angle sensor 13. In addition, the control device 30 acquires data indicating the state of the vehicle, such as acceleration data and vehicle speed data, from an acceleration sensor, a vehicle speed sensor, or the like included in the vehicle state sensor 15.

  In step S <b> 2, control device 30 predicts the current inclination change amount using the detection data acquired from vehicle state sensor 15. The inclination change amount can be predicted based on the difference between the lateral acceleration actually generated in the vehicle and the lateral acceleration predicted from the current traveling state of the vehicle. The actual lateral acceleration is calculated from the detection value of the acceleration sensor. The lateral acceleration is predicted from the vehicle speed and the yaw rate, or from the vehicle speed and the steering angle. The amount of change in inclination is not limited to a lateral angle, and may be predicted from a cant angle. For example, the control device 30 detects the current cant angle at a predetermined cycle using a gradient sensor mounted on the vehicle, and calculates the change amount of the cant angle from the time change of the cant angle. The larger the change amount of the cant angle per time, the larger the predicted change amount of inclination. Note that the amount of change in tilt may be predicted from a captured image of the camera 20. For example, the control device 30 uses the captured image of the camera 20 to detect the inclination of the road surface located in front of the host vehicle, and calculates the difference between the current inclination angle of the road surface and the inclination angle of the front road surface. Calculate. The calculated change amount of the difference corresponds to the inclination change amount.

  In step S3, the control device 30 compares the predicted inclination change amount with a change amount threshold value. The change amount threshold is a preset threshold. When the inclination change amount is less than the change amount threshold value, the control device 30 executes the control flow of step S4. When the inclination change amount is equal to or greater than the change amount threshold value, the control device 30 performs the control flow of step S5. Execute.

In step S4, the control unit 30 sets the integral increase gain _{(k i)} in the normal gain. Usually, the gain is 1. In step S5, the controller 30 sets the increasing gain integral increase gain _{(k i).} The increase gain is a value greater than one. In step S6, the control device 30 executes operation control using the integral term increase gain set in step S4 or step S5.

Details of the control flow from step S4 to step S6 will be described with reference to FIG. FIG. 4 is a block diagram of steering control. FIG. 5 is a diagram illustrating a positional relationship between the host vehicle and another vehicle. In FIG. 5, y _d is relative to the target locus C, showing the lateral displacement of the vehicle.

The control device 30 receives the shift amount (y _d ) and outputs a steering control amount (δ _conf ). The deviation amount is a lateral deviation between the position of the host vehicle and the target locus. The control device 30 measures the position of the host vehicle in the traveling lane using the camera 20 or the like. When the host vehicle is traveling following the target locus, the amount of deviation is zero. On the other hand, when the cant angle changes due to a change in the slope of the road surface and the host vehicle receives a lateral force, the lateral position of the host vehicle deviates from the target trajectory, and the deviation amount becomes larger than zero.

The steering control amount (δ _conf ) is a steering torque command value necessary for generating the steering amount. The steering torque command value is input to the steering unit 1, and the steering unit 1 outputs a steering amount (steering torque) corresponding to the command value. K1 represents a transfer element when the command value (y _cr ) for the deviation amount is input and the steering amount is output. k _i , 1 / s, and K2 represent transfer elements when the difference (Δy) is input and the steering amount is output. The difference (Δy) is a difference (Δy _d ) between the deviation amount (y _cr ) and the deviation amount (y _{d — 0} ) detected by the sensor. k _i is a gain applied to the integral element, and is an integral increase gain. K2 is a gain applied to the integration result. 1 / s represents Laplace transform.

The command value (y _cr ) of the deviation amount is used to match the traveling locus of the own vehicle 40 with the target locus of the own vehicle 40 when the position of the own vehicle 40 is deviated from the target locus C. This is a target value for moving 40 in the horizontal direction. The travel trajectory of the host vehicle indicates the trajectory of the route on which the host vehicle actually travels. The target trajectory is a trajectory of travel that becomes a target when the host vehicle travels by automatic driving or the like. The target locus can be obtained from, for example, a captured image of the camera 20 or the like. The control device 30 calculates the steering control amount (δ _conf ) with respect to the deviation amount command value (y _cr ) using the transfer function shown in the block diagram of FIG. 4. The steering unit 1 outputs a steering torque in response to an input of a steering control amount (δ _conf ). Note that the output of the steering unit 1 is originally the steering torque of the front wheels 3 and 4, but in FIG. 5, for the sake of convenience, the lateral displacement (y _d ) of the host vehicle 40 is used. The deviation amount (y _d ) indicates the deviation amount of the host vehicle 40 after the front wheels 3 and 4 are steered according to the steering control amount (δ _conf ). When there is a disturbance, the amount of deviation corresponding to the output of the steering unit 1 greatly deviates from the command value (y _cr ).

The transfer function is a control function for giving the steering amount to the deviation amount (y _d ), and is a proportional term proportional to the command value (y _cr ) and the FB corresponding to the difference (Δy) in the deviation amount. (Feedback) term is included. The proportional coefficient of the proportional term is K1. The FB term feeds back the detection value detected by the detection unit 60, takes the difference between the detection value and the command value of the deviation amount, and calculates an integral value for the difference. The detection unit 60 corresponds to the steering angle sensor 13.

The transfer function is expressed by the following equation (1).

When the vehicle 40 has a steering amount of δ _p when there is a movement in the transverse direction by Kant (slope), if they meet the following expression (2), the steering amount of the side opposite to the direction in which the vehicle moves by Kant It becomes larger than the steering amount (δ _p ). When the own vehicle moves in the lateral direction, a tire lateral force necessary for canceling the lateral force is generated, and the traveling locus of the own vehicle returns to the target locus.

As shown in Expression (1), since the transfer function includes an integral term, the steering amount with respect to the lateral deviation (deviation) of the host vehicle increases with time. Since the integral term including the integral increase gain (k _i), the more the integral increase gain (k _i) is large, the steering amount increases. Further, since the integral term is expressed by an integral formula of the difference (Δy) in the deviation amount, the steering amount (steering control amount) increases as the lateral deviation amount between the traveling locus of the host vehicle and the target locus increases. .

As shown in FIG. 5, when a lateral movement phenomenon due to canting occurs, the traveling locus M of the host vehicle swells with respect to the target locus C to the side with a lower road surface height. In FIG. 5, the road surface is inclined downward to the left. The target locus C is the center line of the traveling lane. The area (S) of the area surrounded by the travel locus M and the target locus C is an integrated value per hour of the deviation amount (y _d ). In the present embodiment, since the integral term includes the integral increase gain (k _i > 1), the amount of bulge of the travel locus M toward the other side of the vehicle decreases, and the area (S) decreases.

In this embodiment, steering control by a lane keeping support system is performed as normal control. The lane keeping assistance system, the integral increases gain (k _i) is set to a normal gain. For example, when the host vehicle is traveling on a slope with no inclination, if the position of the host vehicle deviates from the target locus due to a crosswind or the like, the control device 30 uses the camera 20 to detect the front state of the vehicle. Based on the captured image of the camera, the lateral deviation of the host vehicle with respect to the target trajectory is calculated. Then, the control device 30 controls the steering amount so that the deviation amount (y _d ) corresponding to the calculated deviation is zero. In this case, the integral increases gain (k _i) is the normal gain.

The traveling road surface of the host vehicle tilts and the cant angle changes. The control device 30 predicts an inclination change amount using detection data of the vehicle state sensor 15 or the like. If the predicted tilt variation exceeds a predetermined variation threshold value, the control device 30, before the vehicle by a change of cant angle is moved in the lateral direction, increasing the gain of the integral increase gain (k _i) Set to. After integration increased gain (k _i) is set to increase gain, slope variation becomes large as expected, the cant angle changes, the own vehicle moves laterally. Since the position of the host vehicle deviates from the target trajectory, the lane keeping support system operates and the steering operation is executed. The steering operation is an operation by automatic driving. In this case, in the present embodiment, since the integral increase gain (k _i) is set to increase gain, the response of the steering amount with respect to an operation input of steering, the response of normal (integral increase gain (k _i ) is higher than responsiveness when set in normal time. In other words, the steering amount (steering torque) for giving the steering amount is larger than the steering amount (steering torque) output at the normal time with respect to the steering operation amount. Thereby, in this embodiment, since it is possible to execute in advance a gain setting that enhances the followability to the target trajectory by predicting a temporarily generated change in the road surface inclination, when a road surface inclination change actually occurs The lateral deviation from the target locus can be eliminated at an early stage.

Then, slope and road surface changes during traveling, the relationship between the integral increase gain (k _i) will be described with reference to FIG. FIG. 6 is a graph for explaining the relationship between the cant change amount and the gain setting. In FIG. 6, the horizontal axis represents time, and the vertical axis represents the cant change amount (dθ / dt). The cant change amount (dθ / dt) represents the change amount of the cant angle per unit time. P _th indicates a positive change threshold value, and −P _th indicates a negative change threshold value. The curve graph is a graph that expresses the change in the slope of the road surface while traveling in terms of time characteristics.

As shown in FIG. 6, from time 0 to time t ₁ corresponding to the origin, the cant change amount is within the range from the upper limit change threshold value (P _th ) to the lower limit change threshold value (−P _th ). , the integral increase gain _{(k i)} is set to the normal gain. At time t _1, since the cant variation is equal to or greater than the change amount threshold (P _th), the integral increases gain (k _i) is changed to increase the gain from the normal gain. During the time _t 1 ~t _2, since the cant variation is greater than or equal to the change amount threshold _{(P th),} the integral increases gain _{(k i)} is maintained at an increased gain. At the time of time t _2, the order cant variation is less than the change amount threshold (P _th), the integral increases gain (k _i) is returned from the increase gain to the normal gain.

From time _{t 2} to time _{t 3,} since cant change amount is in the range from the upper limit of the amount of change threshold _{(P th)} to the lower limit of the amount of change threshold _{(-P th),} the integral increases gain _{(k i)} is Usually maintained at gain. At time t _3, since the cant variation is less variation threshold (-P _th), the integral increases gain (k _i) is changed to increase the gain from the normal gain. Thereafter, until time t _4, the integral increases gain (k _i) is maintained at an increased gain, at time t _4, since the cant variation amount becomes greater than the change amount threshold (-P _th), the integral increases gain _{(k i)} returns usually gain from increased gain.

FIG. 7 is a graph showing the steering amount characteristic. Graphs a and b show characteristics when steering control is executed so as to follow the target locus when the host vehicle moves in the lateral direction due to a change in cant angle. Graph а shows the characteristics when setting the increase gain integral increase gain (k _i), graph b, unlike the present embodiment, showing a characteristic when the integral increase gain (k _i) was normal gain . The horizontal axis represents time (t). The vertical axis represents the steering torque. [delta] _p is the steering amount when the vehicle 40 is pulled into another vehicle 50.

As shown in the graph A, when the integral increase gain (k _i) is set to increase gain at time (t _1), a steering amount for imparting a steering force (steering control amount ([delta] _conf ) Corresponding to the integrated value of) becomes larger than the steering amount (δ _p ). On the other hand, when the integral increase gain _{(k i)} is set to the normal gain, at the point of time _(t 2> t _1), a steering amount for imparting a steering force (steering control amount ([delta] _conf) (Corresponding to the integrated value) becomes larger than the steering amount (δ _p ). That is, in this embodiment, by increasing the integral increase gain (k _i), since the responsiveness of the steering amount for the input to the steering unit 1 is higher than the response of the normal, the transfer function of Equation (1) Is shortened until the integral value included in is increased. As a result, in the present embodiment, it is possible to reduce a deviation in the lateral direction due to a change in inclination.

Figure 8 (а) ~ (e), the cant angle (theta), cant variation (dθ / dt), the lateral displacement ([Delta] y), transverse velocity (Vy), and the characteristics of the integral increase gain _{(k i)} It is a graph to show. The lateral displacement (Δy) is a lateral deviation of the vehicle position with respect to the target locus. The lateral velocity (Vy) corresponds to the time derivative of the lateral displacement. The horizontal axis of each graph indicates time (t). The solid line graph indicates the characteristic (characteristic of the present invention) when executed by the vehicle control system 1000 of the present embodiment, and the broken line graph indicates the characteristic of the comparative example. In the comparative example, when the vehicle actually moves in the lateral direction and the lateral displacement (Δy) becomes greater than zero, control for increasing the integral increase gain is performed.

At time t ₁ , the running slope of the vehicle changes from a horizontal state to a lower left or lower right, and an increase in the cant angle (θ) starts. With increasing cant angles, increasing cant variation (dθ / dt) is, cant variation at time _{t 2} (dθ / dt) is equal to or greater than the change amount threshold _{(P th).} At the time of time t _2, the control unit 30 sets the increase gain integral increase gain (k _i) from the normal gain, as shown in the graph of (e), thereby increasing the gain. At the time of time t _2, the but cant angle and cant variation is increasing, lateral displacement ([Delta] y) remains zero. In other words, since the cant change can be predicted before the vehicle starts to flow into the cant, in the present embodiment, the prediction of the cant change amount predicts that the vehicle will flow into the cant, and the integral increase gain ( k _i ). On the other hand, during the period from time t ₂ to time t _3, since the vehicle is not moved laterally, the integral increases gain according to the comparative example (k _i) is still in the normal gain, the gain is not increased.

At time t _3, the mobile starts in the lateral direction of the vehicle, the lateral displacement ([Delta] y) is greater than zero. At this time, in this embodiment, since the integral increase gain (k _i ) is already in a large state, the response (sensitivity) to the lateral displacement (Δy) is comparative when the steering control for following the target locus is executed. Get higher. In the comparative example, at time t _3, to start the increase of the integral increase gain begins to increase later than the present embodiment.

Time t ₃ after, in the present embodiment, since the integral increase gain before the lateral displacement increases is rising, the variation of lateral displacement ([Delta] y) as shown in the graph (c) is suppressed. At time _{t 4,} cant variation (dθ / dt) becomes smaller than the change amount threshold _{(P th),} the controller 30 returns to the normal gain from increasing the gain of the integral increase gain _{(k i).}

In this embodiment, lateral displacement converges at time t _5. On the other hand, in the comparative example, the lateral displacement converges at time t ₆ (> t ₅ ). That is, this embodiment can shorten the convergence time of lateral displacement compared with the comparative example.

  As described above, in the present embodiment, control is performed so that the steering amount with respect to the time lapse of the deviation in the lateral direction with respect to the traveling lane of the host vehicle is controlled by the first steering amount, and the traveling locus of the own vehicle is returned to the target locus. Execute and predict the inclination change of the traveling road surface of the host vehicle as the inclination change amount using the detection data of the sensor. If the inclination change amount is equal to or larger than a predetermined value, the steering amount is larger than the first steering amount. The second steering amount is set. Thereby, the control time for suppressing the deviation from the target locus in the lateral direction can be suppressed. In addition, it is possible to predict changes in the slope of the road surface and perform control in advance to improve the followability to the target trajectory in advance, so that when the actual road surface changes in slope, the lateral deviation is eliminated early. it can.

  In the present embodiment, when the amount of change in tilt is less than a predetermined value, the steering amount is set to the first steering amount. As a result, when the change in the slope of the road surface becomes small, the followability of the target trajectory returns to the original followability. Therefore, it is possible to reduce a driver's uncomfortable feeling due to frequent steering with respect to the target trajectory.

  In the present embodiment, the lane keeping control may be applied to a driving support system including a lane departure prevention system (lane keeping system) or an automatic driving system that automatically runs the vehicle without requiring any operation by the driver. Good.

  Note that a driving support system including a lane departure prevention system (lane keeping system) does not necessarily have an automatic driving function. For example, when the own vehicle shows a behavior that deviates from the detected lane. Alternatively, the system may be a system that assists the steering operation by the driver when the driver performs a steering operation that notifies the driver of a lane departure by a warning display or a warning sound and returns to the lane.

Incidentally, switching the integral increase gain (k _i) between a normal gain and increasing the gain is not limited to the control flow as in step S3. For example, from the time the gradient variation is smaller than the variation threshold, after a predetermined time has elapsed, the integral increase gain (k _i) may be returned from the increased gain to a normal gain.

Note that "first steering amount" of the present invention corresponds to the steering amount of state set integral increase gain (k _i) in the normal gain (control steering amount), "second steering amount" of the present invention is increased integration It corresponds to the gain (k _i) steering amount of the set conditions of increased gain (control steering amount).

DESCRIPTION OF SYMBOLS 1 ... Steering unit 2 ... Steering wheel 3, 4 ... Wheel 11 ... Shaft 12 ... Motor 13 ... Steering angle sensor 14 ... Torque sensor 20 ... Camera 30 ... Control device 40 ... Own vehicle 50 ... Other vehicle 60 ... Detection unit 100 ... Vehicle Control device 1000 ... Vehicle control system

Claims (3)

A vehicle control method for controlling a vehicle using a vehicle control device including a sensor and a control device mounted on the host vehicle,
Controlling the steering amount with respect to the time lapse of the deviation in the lateral direction with respect to the traveling lane of the host vehicle with the first steering amount, and executing control to return the traveling locus of the own vehicle to the target locus,
Using the detection data of the sensor, predict the change in inclination of the traveling road surface of the vehicle as the amount of change in inclination,
A vehicle control method for setting the steering amount to a second steering amount larger than the first steering amount when the inclination change amount is equal to or greater than a predetermined value. The vehicle control method according to claim 1,
A vehicle control method for setting the steering amount to a first steering amount when the inclination change amount is less than the predetermined value. A sensor mounted on the vehicle,
An actuator for giving a steering amount in a lateral direction to the traveling lane of the host vehicle;
A control device for controlling the actuator,
The control device includes:
A steering amount with respect to the passage of time in the lateral direction with respect to the traveling lane of the host vehicle is set to a first steering amount, and the actuator is operated according to the steering amount to target the traveling locus of the host vehicle. Execute control to return to the path,
Using the detection data of the sensor, predict the change in inclination of the traveling road surface of the vehicle as the amount of change in inclination,
A vehicle control device that sets the steering amount to a second steering amount that is larger than the first steering amount when the tilt change amount is equal to or greater than a predetermined value.

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