Vehicle control device and vehicle control method

Abstract

A vehicle control device according to the present invention, in one embodiment, controls at least one of a target steering angular velocity and a target acceleration / deceleration such that a target vehicle body sideslip angular velocity in a transition state when traveling of a vehicle transitions from the transition state to a steady state becomes a predetermined time rate of change, controls the target steering angular velocity and / or the target acceleration / deceleration such that the target vehicle body sideslip angular velocity becomes a predetermined time rate of change when traveling of the vehicle transitions from the transition state to the steady state. Furthermore, according to one embodiment of the vehicle control method of the present invention, the target steering angular velocity and the target acceleration / deceleration are controlled so as to be constant in the interval from the start of turning of the vehicle to the steady turning. This makes it possible to improve the grip and stability of the vehicle in a transient state in which the vehicle travels.

Description

Technical Field

[0001] The present invention relates to a vehicle control device and a vehicle control method. Background Art

[0002] The vehicle steering device disclosed in Patent Document 1 includes: a main steering mechanism that steers the front wheels using a steering wheel; an auxiliary steering mechanism that steers the front wheel steering angle or the rear wheels using an actuator such as an electric motor according to the vehicle's driving state. The vehicle steering device also includes: a vehicle body sideslip angular velocity calculation unit that detects or estimates the vehicle body sideslip angular velocity at a certain point forward of the rear axle; and a control unit that controls the actuator so as to reduce the absolute value of the vehicle body sideslip angular velocity.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2000-289637 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] However, when the steering mechanism is controlled in such a manner as to reduce the absolute value of the detected value or estimated value of the vehicle body sideslip angular velocity, since the future driving state of the vehicle is not taken into consideration, changes in the vehicle's behavior may occur in a transitional state, for example, when the vehicle is driving in a flat section where the road curvature gradually changes, and there is a possibility that the vehicle's grip and stability may be reduced.

[0008] The present invention has been made in view of the above-mentioned situation, and an object of the present invention is to provide a vehicle control device and a vehicle control method that can improve the grip and stability of a vehicle in a transient state of vehicle travel.

[0009] Technical solutions to technical problems

[0010] According to the vehicle control device of the present invention, in one embodiment, at least one of the target steering angular velocity and the target acceleration / deceleration of the vehicle is controlled so that the target vehicle body sideslip angular velocity in the transition state when the vehicle's travel changes from a transition state to a stable state becomes a specified time change rate.

[0011] Furthermore, according to one aspect of the vehicle control method of the present invention, the target steering angular velocity and target acceleration / deceleration of the vehicle are controlled to be constant in a section from when the vehicle starts turning to when it reaches stable turning.

[0012] Effects of the Invention

[0013] According to the present invention, it is possible to improve the grip feeling and stability feeling of the vehicle in a transient state of vehicle travel. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a block diagram representing a vehicle control system.

[0015] Figure 2 is a line diagram illustrating the transient state of vehicle travel.

[0016] Figure 3 This is a two-wheel model diagram used to illustrate the correlation between the steering angular velocity, acceleration and deceleration, and the vehicle body sideslip angular velocity Δβ.

[0017] Figure 4 1 is a flowchart showing a control process of the vehicle body sideslip angular velocity Δβ according to the first embodiment.

[0018] Figure 5 This is a flowchart showing a second embodiment of a process for controlling the vehicle body sideslip angular velocity Δβ.

[0019] Figure 6 This is a flowchart showing a third embodiment of a process for controlling the vehicle body sideslip angular velocity Δβ.

[0020] Figure 7 This is a time chart showing changes in the steering angle, longitudinal acceleration, and the like when the third embodiment of the control process of the vehicle body sideslip angular velocity Δβ is implemented.

[0021] Figure 8 1 is a block diagram showing a vehicle control device that generates a target trajectory as a control of the vehicle body sideslip angular velocity Δβ.

[0022] Figure 9 This is a block diagram showing the configuration of a target position conversion unit.

[0023] Figure 10 This diagram shows the lateral offset ε at the forward gaze position using the world coordinate system.

[0024] Figure 11 This is a flowchart showing a fourth embodiment of a process for controlling the vehicle body sideslip angular velocity Δβ.

[0025] Figure 12 This is a time chart showing changes in the steering angles of the front and rear wheels, longitudinal acceleration, etc., when the fifth embodiment of the control process of the vehicle body sideslip angular velocity Δβ is implemented.

[0026] Figure 13 This is a flowchart showing a fifth embodiment of a process for controlling the vehicle body sideslip angular velocity Δβ. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of a vehicle control device and a vehicle control method according to the present invention will be described with reference to the accompanying drawings.

[0028] Figure 1 This is a block diagram showing one embodiment of a vehicle control system 200 mounted on the vehicle 100 .

[0029] The vehicle 100 is a four-wheeled vehicle including a pair of left and right front wheels 101 and 102 and a pair of left and right rear wheels 103 and 104 .

[0030] The vehicle control system 200 is an automatic driving system or a driving support system having a function of controlling the motion of the vehicle 100 , and includes a vehicle control device 500 and an actuator unit 600 controlled by the vehicle control device 500 .

[0031] The vehicle control device 500 is an electronic control device including a microcomputer 510 as a control unit that performs calculations based on input information and outputs calculation results.

[0032] The microcomputer 510 includes an MPU (Microprocessor Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, which are not shown in the figure.

[0033] Furthermore, the microcomputer 510 may also be referred to as an MCU (Micro Controller Unit), a processor, a processing device, an arithmetic device, or the like.

[0034] The actuator unit 600 is a device that actively changes the behavior of the vehicle 100 .

[0035] The actuator unit 600 includes a front-wheel steering device 601 for steering the front wheels 101 and 102 using a steer-by-wire method, a rear-wheel steering device 602 for steering the rear wheels 103 and 104, a drive device 603 such as an internal combustion engine or a motor that generates driving force for the vehicle 100, a braking device 604 that applies braking force to each wheel 101-104 of the vehicle 100, and an electronically controlled LSD (Limited-Slip-Differential gear) 605.

[0036] The steer-by-wire method of the front wheel steering device 601 is a steering system that mechanically disconnects the steering wheel operated by the driver from the front wheels 101 and 102 serving as steered wheels and controls the steering angles of the front wheels 101 and 102 by electrical signals.

[0037] Furthermore, the front wheel steering system 601, the rear wheel steering system 602, the drive system 603, the brake system 604, and the electronically controlled LSD 605 all include actuators capable of electronically controlling control variables such as the steering angle, drive force, brake force, and differential limiting force using electrical signals. In this embodiment, the main steering mechanism for operating the front wheels 101 and 102 is a steering wheel, but this is not limiting and any operating device of any size or shape may be used.

[0038] Furthermore, when the vehicle 100 includes a motor as the drive device 603 , the motor can be used as a braking device by generating a regenerative braking force using the motor.

[0039] The microcomputer 510 of the vehicle control device 500 includes a target position information recognition unit 511 , a vehicle information recognition unit 512 , a β angular velocity requirement value calculation unit 513 , a transition region detection unit 514 , and a control amount calculation unit 515 as application programs.

[0040] The target position information identification unit 511 outputs information related to the target position in front of the vehicle 100 (in other words, the forward gaze position). Specifically, it outputs information such as the target speed of the vehicle 100 at the target position, i.e., the target vehicle speed, the target curvature at the target position, the arrival time at the target position (in other words, the forward gaze position time PT), and the distance to the target position (in other words, the forward gaze position distance PD).

[0041] Furthermore, the forward gaze position is set at a predetermined distance in front of the vehicle 100 along the traveling direction of the vehicle 100 , and the predetermined distance is a constant value or a distance that increases as the vehicle speed V becomes higher.

[0042] The target position information identification unit 511 obtains signals from, for example, a GPS (Global Positioning System) receiving unit that measures the latitude and longitude of the vehicle 100, a database of map information, a wireless communication device that performs road-to-vehicle communication and / or vehicle-to-vehicle communication, a camera that obtains image information around the vehicle 100, a radar or LiDAR (Light Detection and Ranging) that detects objects around the vehicle 100, and identifies information related to the target position based on the obtained signals.

[0043] The vehicle information identification unit 512 obtains signals from sensors that detect the vehicle status, such as a yaw rate sensor that detects the yaw rate of the vehicle 100, a lateral acceleration sensor that detects the lateral acceleration of the vehicle 100, a steering angle sensor that detects the steering angles of the front and rear wheels (in other words, tire angles), and a wheel speed sensor that detects the rotational speed of each of the wheels 101-104 of the vehicle 100.

[0044] Furthermore, the vehicle information recognition unit 512 recognizes information related to the motion state of the vehicle 100 , namely, the yaw rate, lateral acceleration, steering angles of the front and rear wheels, and vehicle speed (in other words, vehicle body speed), based on the outputs of these sensors, and outputs a signal of the recognized vehicle information.

[0045] The β angular velocity requirement value calculation unit 513 , the transition region detection unit 514 , and the control amount calculation unit 515 are functional units for executing control of the vehicle body sideslip angular velocity Δβ.

[0046] The control of the vehicle body sideslip angular velocity Δβ is described in detail later, and at least one of the target steering angular velocity and the target acceleration / deceleration of the vehicle 100 is controlled so that the target vehicle body sideslip angular velocity Δβ_tg in the transition state when the driving of the vehicle 100 changes from the transition state to the stable state becomes a specified time change rate.

[0047] In other words, in the control of the vehicle body sideslip angular velocity Δβ, in a transient state, in order to make the future vehicle body sideslip angular velocity Δβ have a prescribed time rate of change, the steering angle velocity or acceleration / deceleration related to the vehicle body sideslip angular velocity Δβ is planned in advance, and the steering angle or vehicle speed is changed according to the plan, thereby controlling the time rate of change of the vehicle body sideslip angular velocity Δβ in the transient state.

[0048] In this manner, the vehicle control device 500 controls the time rate of change of the vehicle body sideslip angular velocity Δβ in the transient state of vehicle travel, thereby suppressing fluctuations in vehicle behavior and improving the grip and stability of the vehicle 100 .

[0049] The transient state in which the vehicle body sideslip angle velocity Δβ is controlled is a state in which the vehicle body sideslip angle β changes, including a turning transition state in which the vehicle 100 is traveling on a flat section of the road and a state in which the vehicle 100 is changing its route for lane change.

[0050] The vehicle body sideslip angle β [rad] is the angle between the traveling direction of the vehicle 100 and the left-right center axis of the vehicle body, and the vehicle body sideslip angular velocity Δβ [rad / s] is the time differential value of the vehicle body sideslip angle β, that is, the first-order differential value of the vehicle body sideslip angle β.

[0051] Furthermore, the vehicle body side slip angular acceleration Δβ [rad / s 2] is the time differential value of the vehicle body sideslip angular velocity Δβ, that is, the second-order differential value of the vehicle body sideslip angle β, which is equivalent to the time change rate of the vehicle body sideslip angular velocity Δβ.

[0052] The β angular velocity requirement value calculation unit 513 obtains signals of the target vehicle speed, the target curvature at the target position, and the arrival time to the target position (in other words, the forward fixation time PT) from the target position information recognition unit 511 .

[0053] Then, the β angular velocity requirement value calculation unit 513 determines a future target vehicle body sideslip angular velocity Δβ_tg based on the acquired signal related to the target position, and outputs a signal of the target vehicle body sideslip angular velocity Δβ_tg.

[0054] In addition, the target vehicle body sideslip angular velocity Δβ_tg can be determined to be a constant value until the target position (in other words, the vehicle body sideslip angular acceleration ΔΔβ is zero). This constant vehicle body sideslip angular velocity Δβ can be achieved by controlling the target steering angular velocity to be constant or controlling the target acceleration / deceleration to be constant.

[0055] However, the target vehicle body sideslip angular velocity Δβ_tg is not limited to being maintained at a constant value until the target position. The target vehicle body sideslip angular velocity Δβ_tg can be arbitrarily set within a range that can improve the grip and stability of the vehicle 100 in a transient state of vehicle travel.

[0056] The transition area detection unit 514 obtains signals of the target vehicle speed, the target curvature at the target position, the arrival time to the target position (in other words, the forward gaze position time PT), and the distance to the target position (in other words, the forward gaze position distance PD) from the target position information recognition unit 511, and obtains signals of the yaw rate, lateral acceleration, steering angles of the front and rear wheels, and vehicle speed from the vehicle information recognition unit 512.

[0057] Then, the transition area detection unit 514 determines whether the driving state of the vehicle 100 is a transition state for executing the control of the vehicle body sideslip angular velocity Δβ based on the obtained signal related to the target position and the signal of the vehicle information, and outputs a signal indicating whether the control of the vehicle body sideslip angular velocity Δβ is turned on or off.

[0058] The control amount calculation unit 515 obtains the signal of the target vehicle body sideslip angular velocity Δβ_tg from the β angular velocity requirement value calculation unit 513, and obtains the signal indicating whether the control of the vehicle body sideslip angular velocity Δβ is turned on or off (in other words, the signal indicating the judgment result of whether it is a transition state) from the transition area detection unit 514.

[0059] In addition, when the control amount calculation unit 515 obtains a signal indicating the implementation of the control of the vehicle body sideslip angular velocity Δβ from the transition area detection unit 514, it outputs a signal of the target steering angle and target speed (in other words, target wheel speed) based on the target vehicle body sideslip angular velocity Δβ_tg to the actuator unit 600.

[0060] Specifically, the vehicle control device 500 generates a vehicle motion plan for causing the vehicle body sideslip angular velocity Δβ to have a predetermined time change rate based on the path information ahead of the vehicle, and controls the steering angle and vehicle speed based on the generated vehicle motion plan.

[0061] Figure 2 1 is a diagram showing a curve in which a gentle section, which is a transition region in which control of the vehicle body sideslip angular velocity Δβ is executed, is set.

[0062] Figure 2 A flat section (specifically, a roundabout section) is set between the arc section (in other words, the stable turning section) and the straight section on the road.

[0063] The arc section is a section where the curvature ρ, that is, the turning radius R, is constant, and the flat section is a section where the curvature ρ changes at a constant rate according to the distance (in other words, the length of the curve).

[0064] Therefore, when the vehicle 100 is Figure 2 When the vehicle 100 travels on a road, the vehicle 100 is in a stable state in a straight section and an arc section, and in a flat section, the vehicle 100 is in a transient state in which the vehicle body sideslip angle β changes.

[0065] Moreover, when the vehicle 100 is in a transition state of traveling in a flat section, specifically, in the first flat section when transitioning from the first flat section to the arc section, or in the second flat section when transitioning from the second flat section to the straight section, the vehicle control device 500 performs control of the vehicle body sideslip angular velocity Δβ.

[0066] Here, the vehicle control device 500 is capable of controlling at least one of the target steering angular velocity and the target acceleration / deceleration of the vehicle 100 so that, in a transitional state where the vehicle 100 is traveling in a flat section, for example, the vehicle body sideslip angular velocity Δβ is maintained at a constant value. In other words, the time differential value of the vehicle body sideslip angular velocity Δβ, i.e., the target vehicle body sideslip angular acceleration ΔΔβ, is maintained at zero.

[0067] Furthermore, the vehicle control device 500 sets the target steering angular velocity or target acceleration / deceleration in the flat section to be constant while setting the vehicle body sideslip angular acceleration ΔΔβ in the flat section to zero, in other words, setting the vehicle body sideslip angular acceleration Δβ to a constant value.

[0068] If the vehicle body sideslip angular velocity Δβ fluctuates significantly in a transient state while the vehicle 100 is traveling, the vehicle behavior fluctuates, which may reduce the grip and stability of the vehicle and impair the occupants' sense of security.

[0069] Therefore, in the process from the initial vehicle body sideslip angle β_in (current value) in the first driving state at the initial stage of the transition state to the target vehicle body sideslip angle β_tg (predicted value) in the second driving state when the transition state is changed to the stable state, the vehicle control device 500 plans in advance the steering angular velocity and acceleration / deceleration from the initial stage of the transition state to the stable state so that the vehicle body sideslip angle β changes at a constant angular velocity.

[0070] That is, the vehicle control device 500 calculates the target body sideslip angle velocity Δβ_tg based on the initial body sideslip angle β_in and the target body sideslip angle β_tg, in which the body sideslip angle β changes at a constant angular velocity so that the body sideslip angle acceleration ΔΔβ is zero, and sets the target steering angular velocity or target acceleration / deceleration so that the body sideslip angle β changes at the target body sideslip angle velocity Δβ_tg.

[0071] As a result, fluctuations in the vehicle body sideslip angular velocity Δβ in a transient state of travel of the vehicle 100 are suppressed, and the grip feeling and stability feeling of the vehicle are improved.

[0072] Here, the first driving state at the initial stage of the transition state is, for example, when the vehicle 100 starts to turn. Figure 2 On a road of , the vehicle 100 enters a flat section from a straight section and starts increasing the steering angle.

[0073] In this case, the second driving state transitioning from the transient state to the stable state refers to, for example, when the vehicle 100 starts turning and then turns steadily. Figure 2 On the road, the vehicle 100 enters the maximum curvature of the arc section from the flat section.

[0074] The first driving state in the initial stage of the transition state is, for example, when the vehicle 100 completes a stable turn and starts increasing or decreasing the steering angle or accelerating or decelerating. Figure 2 On a road of , this refers to when the vehicle 100 enters a flat section from an arc section and starts to return the steering angle.

[0075] In this case, the second driving state transitioning from the transient state to the stable state is, for example, a state in which the vehicle 100 is traveling straight after completing a stable turn. Figure 2 On a road, this refers to when the vehicle 100 enters a straight section from a flat section and the vehicle body sideslip angle β returns to zero.

[0076] The following describes in detail the functions of the β angular velocity requirement value calculation unit 513 , the transition region detection unit 514 , and the control amount calculation unit 515 .

[0077] The transition area detection unit 514 obtains information related to the motion state of the vehicle 100, such as the yaw rate, lateral acceleration, steering angles of the front and rear wheels, and wheel speed, from the vehicle information identification unit 512, and obtains information related to the forward gaze position, such as the target vehicle speed, target curvature, time to the forward gaze position, and distance to the forward gaze position, from the target position information identification unit 511.

[0078] Then, the transition region detection unit 514 calculates the vehicle body sideslip angular velocity Δβ at the current moment based on the various information obtained, and further calculates the target lateral acceleration αy_tg at the forward gaze position.

[0079] Here, when the vehicle body sideslip angular velocity Δβ at the current moment is not zero and the difference between the target lateral acceleration αy_tg and the lateral acceleration αy_ac at the current moment is not zero, the transition area detection unit 514 determines that the vehicle 100 is in a transition state, and outputs a signal indicating the implementation of control of the vehicle body sideslip angular velocity Δβ to the control amount calculation unit 515.

[0080] If the curvature information at the forward gaze position can be obtained as road shape information, or if it can be obtained based on the lateral offset from the target route in the second driving state, the lateral acceleration αy_tg, yaw rate γ_tg, and vehicle body sideslip angle β_tg in the centrifugal force-free state under the stability circle can be calculated as shown in Mathematical Formula 1.

[0081] Furthermore, if the segment is a flat segment preceding the arc segment, the curvature information at the forward gaze position is the information of the maximum curvature.

[0082] [Mathematical formula 1]

[0083]

[0084] Therefore, the transition area detection unit 514 can detect a situation in which the curvature ρ increases in the future and the vehicle body sideslip angle β increases, or a situation in which the curvature ρ decreases in the future and the vehicle body sideslip angle β decreases, by comparing the target lateral acceleration αy_tg in the stable state calculated based on the curvature at the forward gaze position with the current lateral acceleration αy_ac.

[0085] Furthermore, when the current vehicle sideslip angle velocity Δβ is not zero, the transition region detection unit 514 can detect that the vehicle 100 is in a transition state and instruct to implement control of the vehicle sideslip angle velocity Δβ in response to future changes in the vehicle sideslip angle β.

[0086] The β angular velocity requirement value calculation unit 513 calculates the vehicle body sideslip angular velocity Δβ when the vehicle body sideslip angle β changes from the initial vehicle body sideslip angle β_in to the target vehicle body sideslip angle β_tg at a constant angular velocity based on the initial vehicle body sideslip angle β_in, the target vehicle body sideslip angle β_tg, and the predicted arrival time to the position of the target vehicle body sideslip angle β_tg, and outputs the signal of the target vehicle body sideslip angular velocity Δβ_tg to the control quantity calculation unit 515 as the target vehicle body sideslip angular velocity Δβ_tg.

[0087] Furthermore, the fact that the target vehicle body sideslip angular velocity Δβ_tg is a constant value corresponds to the fact that the target vehicle body sideslip angular acceleration Δβ_tg is zero.

[0088] When the transition region detection unit 514 determines the transition state of the vehicle 100 and outputs a signal instructing implementation of the control of the vehicle body sideslip angle velocity Δβ, the control amount calculation unit 515 outputs a control target for changing the vehicle body sideslip angle β at the target vehicle body sideslip angle velocity Δβ_tg to the actuator unit 600.

[0089] In detail, the control quantity calculation unit 515 calculates a target steering angle according to a target steering angular velocity for changing the vehicle body sideslip angle β at a target vehicle body sideslip angular velocity Δβ_tg, and a target rotational angular velocity (in other words, a target wheel speed) according to a target acceleration / deceleration for changing the vehicle body sideslip angle β at a target vehicle body sideslip angular velocity Δβ_tg, and outputs a signal of the target steering angle and a signal of the target rotational angular velocity to the actuator unit 600.

[0090] Here, when the target vehicle body sideslip angular velocity Δβ_tg is a constant value, the target steering angle and the target acceleration / deceleration are constant.

[0091] Next, refer to Figure 3 The two-wheel model shows that the vehicle side slip angular velocity Δβ can be controlled by controlling the steering angular velocity and acceleration and deceleration.

[0092] In addition, γ is the yaw rate, βf is the front wheel side slip angle, βr is the rear wheel side slip angle, L is the wheelbase, Lf is the distance from the center of gravity to the front axle, Lr is the distance from the center of gravity to the rear axle, m is the vehicle weight, Yf is the front wheel lateral force, and Yr is the rear wheel lateral force.

[0093] The lateral acceleration αy is obtained by using Equation 2 based on the vehicle body sideslip angular velocity Δβ, the yaw rate γ, and the vehicle speed V.

[0094] [Mathematical formula 2]

[0095]

[0096] On the other hand, the front wheel side slip angle βf and the rear wheel side slip angle βr are obtained according to Mathematical Formula 3.

[0097] [Mathematical formula 3]

[0098]

[0099] Here, when the front wheel side slip angle βf and the rear wheel side slip angle βr are used to express the yaw rate γ, the yaw rate γ is expressed as Equation 4. When the front wheel side slip angle βf and the rear wheel side slip angle βr are used to express the vehicle body side slip angle β, the yaw rate γ is expressed as Equation 5.

[0100] [Formula 4]

[0101]

[0102] [Formula 5]

[0103]

[0104] Furthermore, differentiating Math. Equations 4 and 5 respectively yields Math. Equations 6 and 7.

[0105] [Formula 6]

[0106]

[0107] [Formula 7]

[0108]

[0109] Furthermore, according to the vehicle's motion equation, Mathematical Formula 8 holds true. In Mathematical Formula 8, Iz is the moment of inertia.

[0110] [Formula 8]

[0111]

[0112] Furthermore, the motion equation expressing the two-degree-of-freedom motion using the front wheel sideslip angle βf and the rear wheel sideslip angle βr becomes Formula 9 when the front wheel steering angle is set to δ, the rear wheel steering angle is set to δr, and the turning coefficients of the front and rear wheels are set to Cf and Cr.

[0113] [Formula 9]

[0114]

[0115] As shown in Mathematical Formula 7, the vehicle body side slip angular velocity Δβ changes according to the front wheel side slip angular velocity Δβf and the rear wheel side slip angular velocity Δβr.

[0116] As shown in Mathematical Formula 9, the front wheel side slip angular velocity Δβf and the rear wheel side slip angular velocity Δβr change according to the front wheel steering angle δ, the rear wheel steering angle δr, and the vehicle speed V.

[0117] Therefore, the vehicle control device 500 can control the vehicle body sideslip angular velocity Δβ in the transition state by controlling the front wheel steering angle δ, the rear wheel steering angle δr, and the vehicle speed V, and can control the target vehicle body sideslip angular velocity Δβ_tg when the vehicle body sideslip angle β changes toward the target vehicle body sideslip angle β_tg to a specified time change rate by controlling the target steering angular velocity and the target acceleration / deceleration.

[0118] Then, the vehicle control device 500 controls the target vehicle body sideslip angular velocity Δβ_tg in the transient state of the vehicle 100 to a predetermined time change rate, thereby suppressing the fluctuation of the vehicle behavior in the transient state and improving the grip and stability of the vehicle 100.

[0119] Hereinafter, a process of controlling the vehicle body sideslip angular velocity Δβ executed by the vehicle control device 500 (specifically, the microcomputer 510 ) will be described.

[0120] Figure 4 1 is a flowchart showing a control procedure when the vehicle control device 500 controls the target steering angular velocities of the front and rear wheels so that the target vehicle body sideslip angular velocity Δβ_tg is constant in a transient state.

[0121] In step S21 , the vehicle control device 500 acquires information on the target vehicle speed, road curvature, distance to the forward gaze position, and time at the forward gaze position from the route information of the vehicle 100 .

[0122] Next, in step S22, the vehicle control device 500 calculates the lateral acceleration αy at the forward gaze position of the vehicle 100, i.e., the position of maximum curvature, as the target lateral acceleration αy_tg based on the target vehicle speed, curvature, and time to the forward gaze position.

[0123] Furthermore, in step S22 , the vehicle control device 500 calculates the target vehicle body sideslip angle β_tg, which is the vehicle body sideslip angle β at the forward focus position, based on the target lateral acceleration αy_tg and the target vehicle speed.

[0124] Furthermore, when the vehicle control device 500 can obtain information on the shape of the road ahead of the vehicle 100 , it identifies the maximum curvature position of the ahead curve and calculates the target lateral acceleration αy_tg and the target vehicle body sideslip angle β_tg based on the maximum curvature information.

[0125] The maximum curvature position is when the vehicle 100 travels in the arc section after passing the flat section. At the end of the flat section, the maximum curvature is the curvature of the arc section.

[0126] Furthermore, when the vehicle 100 is traveling toward the exit of a curve, in other words, when the vehicle 100 is traveling in a flat section immediately before a straight section, the vehicle control device 500 sets the target vehicle body sideslip angle β_tg and the target lateral acceleration αy_tg to zero.

[0127] Then, in step S23 , the vehicle control device 500 calculates the vehicle body sideslip angular velocity Δβ at the current moment based on the detected value of the vehicle speed V and the detected value of the lateral acceleration αy (in other words, the lateral acceleration αy_ac at the current moment).

[0128] Then, in step S24 , the vehicle control device 500 determines whether the absolute value of the difference Dαy between the target lateral acceleration αy_tg and the current lateral acceleration αy_ac is greater than or equal to a predetermined value THαy (THαy>0) as a first condition for determining the transient state of the vehicle 100 .

[0129] Here, when the difference Dαy is equal to or greater than the predetermined value THαy and a transition state to the forward gaze position is predicted, the vehicle control device 500 proceeds to step S25 and thereafter.

[0130] On the other hand, when the first condition for the transition determination, that is, the difference Dαy is equal to or greater than the predetermined value THαy, is not satisfied, the vehicle control device 500 ends this routine without performing the control of the vehicle body sideslip angular velocity Δβ.

[0131] In step S25 , the vehicle control device 500 calculates a target steering angular velocity Δδ_tg for changing the vehicle body sideslip angle β by the target vehicle body sideslip angular velocity Δβ_tg from the current vehicle body sideslip angle β (in other words, the initial vehicle body sideslip angle β_in) to the target vehicle body sideslip angle β_tg.

[0132] Here, the vehicle control device 500 calculates the target steering angular velocity Δδ_tg, which is the target steering angle when the current steering angle is changed to the target vehicle body sideslip angle β_tg at a constant angular velocity, while keeping the target vehicle body sideslip angular velocity Δβ_tg constant in the transient state.

[0133] In other words, the vehicle control device 500 sets the target steering angular velocity Δδ_tg in the transient state to a constant value, thereby making the target vehicle body sideslip angular velocity Δβ_tg in the transient state a constant value.

[0134] Next, in step S26 , the vehicle control device 500 determines whether the current vehicle body sideslip angular velocity Δβ is equal to or less than a predetermined value, for example, whether the current vehicle body sideslip angular velocity Δβ is zero, as a second condition for determining the transient state of the vehicle 100 .

[0135] That is, the vehicle control device 500 determines in step S26 whether the vehicle body sideslip angle β is changing or the vehicle body sideslip angle β is maintaining a constant value.

[0136] Here, when the vehicle body sideslip angular velocity Δβ is not zero and the vehicle 100 is in a transitional state where the vehicle body sideslip angle β changes, the vehicle control device 500 enters step S27 and executes control to change the steering angle according to the target steering angular velocity Δδ_tg calculated in step S25.

[0137] Specifically, in step S27 , the vehicle control device 500 determines a steering angular velocity gain based on the target steering angular velocity Δδ_tg, and outputs a steering control current based on the steering angular velocity gain to the front wheel steering device 601 and the rear wheel steering device 602 .

[0138] Furthermore, the vehicle control device 500 can control only the front-wheel steering device 601 of the front-wheel steering device 601 and the rear-wheel steering device 602 in controlling the vehicle body sideslip angular velocity Δβ.

[0139] As described above, after calculating the target steering angular velocity Δδ_tg in step S25 , the vehicle control device 500 determines the vehicle body sideslip angular velocity Δβ in step S26 , in other words, determines whether to start control of the vehicle body sideslip angular velocity Δβ.

[0140] Therefore, from the moment when the first condition related to the lateral acceleration is satisfied before the second condition related to the vehicle body sideslip angular velocity Δβ, the calculation process of the target steering angular velocity Δδ_tg is repeatedly performed in preparation for the start of control, thereby preventing a delay in the calculation cycle of the control amount when it is determined to be the start of control.

[0141] On the other hand, when the vehicle body sideslip angular velocity Δβ is zero and the vehicle 100 is traveling in a stable state, the vehicle control device 500 does not control the vehicle body sideslip angular velocity Δβ and ends this routine.

[0142] That is, although there is a transition area in front of the vehicle 100, when the vehicle 100 has not entered the transition area, for example, when the vehicle 100 is traveling in a straight section in front of a flat section, the vehicle control device 500 repeatedly calculates and processes the target steering angular velocity Δδ_tg and stands by until the transition state is reached.

[0143] As described above, the vehicle control device 500 implements Figure 4 The process shown in the flowchart of FIG. 1 changes the steering angle along a constant target steering angular velocity Δδ_tg in a transient state such as driving in a flat section, thereby suppressing the change in the vehicle body sideslip angular velocity Δβ in the transient state.

[0144] Figure 5 1 is a flowchart showing a control procedure when the vehicle control device 500 controls the target acceleration / deceleration of the vehicle 100 so that the vehicle body sideslip angular velocity Δβ is constant in the transient state.

[0145] exist Figure 5 In each step of step S31 to step S34 of the flowchart of Figure 4 Since the processes in steps S21 to S24 of the flowchart are the same, detailed descriptions are omitted here.

[0146] When the vehicle control device 500 determines in step S34 that the difference Dαy is equal to or greater than the predetermined value THαy, the process proceeds to step S35 .

[0147] Next, in step S35 , the vehicle control device 500 determines a target acceleration / deceleration AD_tg for changing the vehicle body sideslip angle β from the current vehicle body sideslip angle β (in other words, the initial vehicle body sideslip angle β_in) to the target vehicle body sideslip angle β_tg at a target vehicle body sideslip angle velocity Δβ_tg.

[0148] Here, when the target vehicle body sideslip angle Δβ_tg is set to a constant value in the transient state, the vehicle control device 500 calculates the target acceleration / deceleration AD_tg, which is the target vehicle speed when changing from the current vehicle speed to the target vehicle body sideslip angle β_tg at a constant acceleration / deceleration.

[0149] In other words, the vehicle control device 500 sets the target acceleration / deceleration AD_tg in the transient state to a constant value, thereby making the target vehicle body sideslip angular velocity Δβ_tg in the transient state a constant value.

[0150] Next, in step S36 , the vehicle control device 500 determines whether the vehicle body sideslip angular velocity Δβ at the current moment is zero, similarly to step S26 .

[0151] Then, when the vehicle control device 500 determines in step S36 that the vehicle body sideslip angular velocity Δβ at the current moment is not zero, the process proceeds to step S37 .

[0152] In step S37 , the vehicle control device 500 executes control to change the vehicle speed in accordance with the target acceleration / deceleration AD_tg obtained in step S35 .

[0153] Specifically, the vehicle control device 500 determines the rotation speed gain based on the target acceleration / deceleration AD_tg in step S37 .

[0154] Furthermore, the vehicle control device 500 outputs a drive control current based on the rotation speed gain to the drive device 603 during acceleration, and outputs a brake control current based on the rotation speed gain to the brake device 604 during deceleration.

[0155] As described above, the vehicle control device 500 implements Figure 5 The process shown in the flowchart of FIG. 1 changes the vehicle speed (wheel speed) along a constant target acceleration / deceleration AD_tg in a transient state such as driving in a flat section, thereby suppressing the fluctuation of the vehicle body sideslip angular velocity Δβ in the transient state.

[0156] Figure 6 1 is a flowchart showing a control procedure when the vehicle control device 500 controls both the target steering angular velocity and the target acceleration / deceleration so as to keep the vehicle body sideslip angular velocity Δβ constant in the transient state.

[0157] exist Figure 6 In each step of step S41 to step S44 of the flowchart of Figure 4 Since the processes in steps S21 to S24 of the flowchart are the same, detailed descriptions are omitted here.

[0158] When the vehicle control device 500 determines in step S44 that the difference Dαy is equal to or greater than the predetermined value THαy, the vehicle control device 500 performs the processing of step S45 and the processing of step S46 in parallel.

[0159] The vehicle control device 500 obtains the target steering angular velocity Δδ_tg in step S45 in the same manner as in step S25 , and obtains the target acceleration / deceleration AD_tg in step S46 in the same manner as in step S35 .

[0160] Next, in step S47 , the vehicle control device 500 determines whether the vehicle body sideslip angular velocity Δβ at the current moment is zero, similarly to step S26 .

[0161] Then, when the vehicle control device 500 determines in step S47 that the vehicle body sideslip angular velocity Δβ at the current moment is not zero, the process proceeds to step S48 .

[0162] In step S48 , the vehicle control device 500 determines the steering angular velocity gain based on the target steering angular velocity Δδ_tg, similarly to step S27 , and outputs a steering control current based on the steering angular velocity gain to the front wheel steering device 601 and the rear wheel steering device 602 .

[0163] Furthermore, in step S48, the vehicle control device 500 determines the speed gain based on the target acceleration / deceleration AD_tg, similarly to step S37. If accelerating, the driving control current based on the speed gain is output to the driving device 603. If decelerating, the braking control current based on the speed gain is output to the braking device 604.

[0164] As described above, the vehicle control device 500 implements Figure 6The process shown in the flowchart is as follows: in a transient state such as driving in a flat section, the steering angle is changed based on a constant target steering angular velocity Δδ_tg, and the vehicle speed (wheel speed) is changed along a constant target acceleration / deceleration AD_tg, thereby suppressing the change in the vehicle body sideslip angular velocity Δβ in the transient state.

[0165] Figure 7 The timing diagram shows changes in the front wheel steering angle, wheel speed, vehicle body sideslip angle β, lateral acceleration, and longitudinal acceleration when the vehicle 100 travels on a curved road from a straight section → a flat section → an arc section → a flat section → a straight section.

[0166] also, Figure 7 The solid line represents a state in which the vehicle control device 500 controls the vehicle body sideslip angular velocity Δβ (specifically, controls to keep the target steering angular velocity and the target acceleration / deceleration constant). Figure 7 The dotted line indicates a state where the vehicle body sideslip angular velocity Δβ is not controlled.

[0167] Without controlling the vehicle body sideslip angle Δβ, in a transient state where the vehicle 100 is traveling in a flat section, the vehicle body sideslip angle β fluctuates unstably with changes in the steering angular velocity and acceleration, thereby reducing the grip and stability of the vehicle 100.

[0168] In contrast, when the vehicle body sideslip angular velocity Δβ is controlled, the target steering angular velocity and target acceleration / deceleration (in other words, target fore-aft acceleration) are controlled to be constant in the transition state, so that the vehicle body sideslip angle β changes at a constant angular velocity Δβ, thereby improving the grip and stability of the vehicle 100 in the transition state.

[0169] However, the vehicle control device 500 can generate a target trajectory of the vehicle 100 based on the target position of the vehicle 100 at which the target vehicle body sideslip angular velocity Δβ_tg changes at a predetermined time rate.

[0170] That is, the vehicle control device 500 can generate a target trajectory incorporating the target steering angular velocity Δδ_tg or the target acceleration / deceleration AD_tg at which the target vehicle body sideslip angular velocity Δβ_tg changes at a predetermined time rate, and control the actuator unit 600 to track the target trajectory.

[0171] Figure 8 1 is a block diagram showing a vehicle control device 500 that generates a target trajectory as a control of the vehicle body sideslip angular velocity Δβ.

[0172] Figure 8 The vehicle control device 500 shown has a target position conversion unit 516 instead of Figure 1The vehicle control device 500 shown includes a β angular velocity request value calculation unit 513.

[0173] The target position conversion unit 516 is a functional unit that obtains a target vehicle position that incorporates the vehicle body sideslip angular velocity Δβ_tg.

[0174] Figure 9 It is a block diagram showing in detail the signal transmission path in the target position conversion unit 516.

[0175] in addition, Figure 10 This diagram shows the lateral offset ε of the forward gaze position of the vehicle 100 from the target track using the world coordinate system.

[0176] Here, the lateral offset amount ε is calculated according to the following formula.

[0177]

[0178] Then, the target position conversion unit 516 converts the lateral offset amount ε into a steering angle δ, and calculates the vehicle body sideslip angle β and yaw rate γ according to equations 10 and 11.

[0179] [Formula 10]

[0180]

[0181] [Mathematical formula 11]

[0182]

[0183] Furthermore, the target position conversion unit 516 calculates the front vehicle speed and the lateral vehicle speed according to Mathematical Formulas 12 and 13 based on the vehicle body sideslip angle β and the yaw rate γ.

[0184] [Mathematical formula 12]

[0185]

[0186] [Mathematical formula 13]

[0187]

[0188] Then, the target position conversion unit 516 adds the target vehicle body sideslip angular velocity Δβ_tg, and calculates the front vehicle position x and the lateral vehicle position y representing the target vehicle position according to mathematical formula 14 and display formula 15, and outputs the information of the target vehicle position (specifically, the front vehicle position x and the lateral vehicle position y) as information related to the target trajectory to the control amount calculation unit 515.

[0189] The control amount calculation unit 515 controls the actuator unit 600 in accordance with the acquired target vehicle position.

[0190] [Formula 14]

[0191]

[0192] [Mathematical formula 15]

[0193]

[0194] Figure 11 1 is a flowchart showing a control procedure when planning a target trajectory in consideration of the target vehicle body sideslip angular velocity Δβ_tg.

[0195] exist Figure 11 In each step of step S51 to step S54 of the flowchart of Figure 4 Since the processes in steps S21 to S24 of the flowchart are the same, detailed descriptions are omitted here.

[0196] When the vehicle control device 500 determines in step S54 that the difference Dαy is equal to or greater than the predetermined value THαy, the process proceeds to step S55 .

[0197] In step S55 , the vehicle control device 500 calculates a target vehicle position incorporating the target vehicle body sideslip angular velocity Δβ_tg.

[0198] As mentioned above, the target vehicle position is determined by Figure 8 The target position conversion unit 516 shown is calculated according to equations 14 and 15.

[0199] Next, in step S56 , the vehicle control device 500 calculates a control variable of each device that becomes a target value for causing the vehicle 100 to follow the target vehicle position merging into the target vehicle body sideslip angular velocity Δβ_tg.

[0200] Then, in step S57 , the vehicle control device 500 determines whether the vehicle 100 is in the transient state by determining whether the vehicle body sideslip angular velocity Δβ at the current moment is zero.

[0201] Here, when the vehicle body sideslip angular velocity Δβ at the current moment is not zero, the vehicle control device 500 enters step S58, controls the braking driving force based on the control amount calculated in step S56, and further, controls the steering angles of the front and rear wheels so that the vehicle 100 follows and merges into the target vehicle position of the target vehicle body sideslip angular velocity Δβ_tg.

[0202] In this way, the vehicle control device 500 incorporates the trajectory of the target vehicle body sideslip angular velocity Δβ_tg through planning. In other words, by correcting the target trajectory in a manner that can achieve the target vehicle body sideslip angular velocity Δβ_tg, for example, it can achieve transitional driving with a constant target vehicle body sideslip angular velocity Δβ_tg, thereby improving the grip and stability of the vehicle 100 in the transitional state of vehicle driving.

[0203] Furthermore, when the target vehicle body sideslip angular velocity Δβ_tg is set to a constant value, the target trajectory incorporating the target vehicle body sideslip angular velocity Δβ_tg becomes a target trajectory in which the target steering angular velocity and the target acceleration / deceleration are constant in the transition region.

[0204] The control of the vehicle body sideslip angular velocity Δβ by the vehicle control device 500 is not limited to the control of setting the target vehicle body sideslip angular velocity Δβ_tg in the transient state to a constant value, that is, the control of setting the target vehicle body sideslip angular velocity Δβ_tg in the transient state to zero.

[0205] Figure 12 Δβ_tg is a time chart showing an example of a target vehicle body sideslip angular velocity Δβ_tg that is not a constant value in a transient state.

[0206] exist Figure 12 In the example shown, the target vehicle body sideslip angular velocity Δβ_tg is set so that at the beginning of the transition area, specifically, at the beginning of the vehicle 100 entering the flat section from the straight section and at the beginning of the vehicle body entering the flat section from the arc section, the vehicle body sideslip angle β changes at a constant angular velocity toward the side where the vehicle body turns outward.

[0207] Then, the target vehicle body sideslip angular velocity Δβ_tg is set so that the vehicle body sideslip angle β reverses its changing direction at a certain angle and returns to zero, and changes at a constant angular velocity toward the maximum curvature when the vehicle body turns inward.

[0208] That is, in Figure 12 In the example shown, the target vehicle body sideslip angular velocity Δβ_tg is initially set in the direction opposite to the vehicle body sideslip angle β at the forward viewing position in the transition region, and then reverses to the direction toward the vehicle body sideslip angle β at the forward viewing position.

[0209] Compared with the case where the vehicle body sideslip angle β is changed from the moment the vehicle 100 enters the transition area to the vehicle body sideslip angle β at the forward viewing position, temporarily changing the vehicle body sideslip angle β toward the outside of the vehicle body turning and then changing the vehicle body sideslip angle β toward the forward viewing position can further improve the grip of the vehicle 100.

[0210] In addition, when the vehicle 100 first enters the flat section from the straight section, Figure 12As shown by the middle dashed line, even when the vehicle body sideslip angular velocity Δβ is not controlled, the vehicle body sideslip angle β temporarily changes to the outside of the vehicle body turn.

[0211] Here, the initial target body sideslip angular velocity Δβ_tg of the vehicle 100 when entering the flat section from the straight section is set so that the magnitude of the body sideslip angle β when the body turns outward does not become larger than when the body sideslip angular velocity Δβ is not controlled, and is set so that after the body sideslip angle β returns to zero, the body sideslip angle β toward the maximum curvature changes at a certain angle.

[0212] By setting the target vehicle body sideslip angular velocity Δβ_tg, the change in the vehicle body sideslip angle β in the transient state is controlled, thereby further improving the grip and stability of the vehicle.

[0213] Furthermore, the vehicle control device 500 can variably set the target vehicle body sideslip angle speed Δβ_tg, the target period, and the like when changing the vehicle body sideslip angle β in the opposite direction at the initial stage of the transition, based on the curvature change rate, the vehicle speed, and the like.

[0214] Furthermore, the target vehicle body sideslip angular velocity Δβ_tg when changing the vehicle body sideslip angle β from zero toward the vehicle body sideslip angle β at the maximum curvature is not limited to a constant value, and a change in the angular velocity within a predetermined range is permitted.

[0215] The vehicle control device 500 controls the change in the vehicle side slip angle β when the vehicle turns outward by reducing the longitudinal acceleration and steering the rear wheels 103 and 104 in opposite phases.

[0216] Furthermore, the microcomputer 510 controls the difference in braking and driving force between the left and right wheels to control the turning moment generated in the vehicle 100 and to control the change in the vehicle body sideslip angle β when the vehicle body turns outward.

[0217] Figure 13 The vehicle control device 500 sets the target vehicle body sideslip angular velocity Δβ_tg in the transient state to Figure 12 This is a flowchart of a control process when controlling the target steering angular velocity, target acceleration / deceleration, etc. of the front and rear wheels using a predetermined time rate of change.

[0218] exist Figure 13 In each step of step S61 to step S64 of the flowchart of Figure 4 Since the processes in steps S21 to S24 of the flowchart are the same, detailed descriptions are omitted here.

[0219] When the vehicle control device 500 determines in step S64 that the transition determination condition is satisfied, that is, the difference between the target lateral acceleration αy_tg and the current lateral acceleration αy_ac is equal to or greater than a predetermined value, the process in step S65 and the process in step S66 are executed in parallel.

[0220] In step S65, the vehicle control device 500 makes the target vehicle body sideslip angular velocity Δβ_tg become, for example Figure 12 The target steering angular velocity Δδ_tg toward the forward gaze position is calculated in a time series manner using a predetermined time change rate as exemplified.

[0221] Here, in Figure 12 In the example shown, a target steering angular velocity Δδ_tg is calculated so that the steering angles of the rear wheels 103 and 104 are in opposite phases at the initial stage of transition.

[0222] In addition, in step S66, the vehicle control device 500 makes the target vehicle body sideslip angular velocity Δβ_tg become, for example Figure 12 In the example of the predetermined time change rate, the target acceleration / deceleration AD_tg toward the forward gaze position is calculated in a time series manner.

[0223] It should be noted that, as described above, in order to change the vehicle body sideslip angle β toward the outside of the vehicle body turn at the initial stage of the transition, the vehicle control device 500 can generate a rotational torque by controlling the braking-driving force difference between the left and right wheels and controlling the electronically controlled LSD.

[0224] After calculating the target steering angular velocity Δδ_tg and the target acceleration / deceleration AD_tg, the vehicle control device 500 proceeds to step S67 to determine whether the vehicle body sideslip angular velocity Δβ at the current moment is zero.

[0225] Here, when the vehicle body sideslip angular velocity Δβ is not zero and the travel of the vehicle 100 is in a transient state, the vehicle control device 500 proceeds to step S68 and executes control of the vehicle body sideslip angular velocity Δβ.

[0226] In step S68, the vehicle control device 500 determines the wheel speed gain based on the target acceleration / deceleration AD_tg at this time, and outputs the braking drive control current to the drive device 603 and the braking device 604 respectively. In addition, the steering angular velocity gain is determined based on the target steering angular velocity Δδ_tg at this time, and the steering control current is output to the front wheel steering device 601 and the rear wheel steering device 602 respectively.

[0227] On the other hand, when the vehicle body sideslip angular velocity Δβ is zero and the vehicle 100 is in a stable state, that is, in a stable state before entering a transient state, the vehicle control device 500 ends this routine without controlling the vehicle body sideslip angular velocity Δβ.

[0228] As described above, the vehicle control device 500 controls the target steering angular velocity and target acceleration / deceleration so that the target vehicle body sideslip angular velocity Δβ_tg becomes a predetermined time change rate that is not a constant value. This can further improve the vehicle's grip and stability compared to when the target vehicle body sideslip angular velocity Δβ_tg is set to a constant value.

[0229] The technical concepts described in the above embodiments can be used in appropriate combination as long as no contradiction occurs.

[0230] Furthermore, while the present invention has been described in detail with reference to preferred embodiments, it is apparent that those skilled in the art can employ various modifications based on the basic technical concept and teachings of the present invention.

[0231] For example, the vehicle control device 500 can add a condition that the vehicle speed V exceeds a predetermined speed (for example, predetermined speed = 40 km / h) as an execution condition for controlling the vehicle body sideslip angular velocity Δβ.

[0232] The vehicle speed V condition is used to control the vehicle body sideslip angular velocity Δβ in the medium and high vehicle speed ranges, which can help improve grip and stability. By adding the vehicle speed V condition, it is possible to prevent unnecessary and ineffective control from being implemented in the low vehicle speed range.

[0233] When the vehicle 100 includes an internal combustion engine as the drive device 603 , the vehicle control device 500 can control the throttle opening according to the target acceleration / deceleration.

[0234] Furthermore, the vehicle 100 can control the vehicle body sideslip angular velocity Δβ either when the vehicle 100 enters a flat section from a straight section or when the vehicle 100 enters a flat section from an arc section.

[0235] Description of Reference Numerals

[0236] 100: Vehicle

[0237] 500: Vehicle control device

[0238] 510: Microcomputer (control unit)

[0239] 513: β angular velocity requirement value calculation unit

[0240] 514: Transition Area Detection Department

[0241] 515: Control quantity calculation unit

[0242] 600: Actuator

[0243] 601: Front wheel steering gear

[0244] 602: Rear wheel steering device

[0245] 603: Drive device

[0246] 604: Braking device

Claims

1. A vehicle control device, characterized in that: The control unit of the vehicle control device controls at least one of a target steering angular velocity and a target acceleration / deceleration of the vehicle so that the target vehicle body sideslip angular velocity in the transient state when the vehicle travel transitions from a transient state to a stable state has a predetermined time change rate.

2. The vehicle control device according to claim 1, wherein: The prescribed time rate of change is zero.

3. The vehicle control device according to claim 2, characterized in that The control unit controls the target steering angular velocity to be constant, or controls the target acceleration / deceleration to be constant.

4. The vehicle control device according to claim 3, wherein: The control unit acquires an initial vehicle body sideslip angle based on the vehicle speed and the vehicle lateral acceleration in a first driving state indicating an initial stage of the transient state. obtaining a target vehicle body sideslip angle based on a target speed of the vehicle and a target lateral acceleration of the vehicle in a second driving state in which the driving of the vehicle transitions from the first driving state to the stable state, The target vehicle body sideslip angle velocity is obtained based on the initial vehicle body sideslip angle and the target vehicle body sideslip angle.

5. The vehicle control device according to claim 4, characterized in that: The first driving state is the state when the vehicle starts to turn. The second running state is a state in which the vehicle is turning stably after starting to turn.

6. The vehicle control device according to claim 4, characterized in that The first driving state is a state in which the vehicle starts to increase or decrease the steering angle or starts to accelerate or decelerate after the vehicle completes a stable turn. The second traveling state is a state in which the vehicle travels straight after the vehicle completes a stable turn.

7. The vehicle control device according to claim 4, characterized in that: The control unit executes the control when the vehicle body sideslip angular velocity is not zero and there is a difference between the target lateral acceleration and the lateral acceleration.

8. The vehicle control device according to claim 1, wherein: The control unit controls both the target steering angular velocity and the target acceleration / deceleration.

9. The vehicle control device according to claim 1, wherein: The control unit generates a target trajectory of the vehicle based on a target position of the vehicle at which the target vehicle body sideslip angular velocity changes at a predetermined time rate.

10. A vehicle control method, executed by a control unit provided in a vehicle, characterized in that: The control unit controls a target steering angular velocity and a target acceleration / deceleration of the vehicle to be constant in a period from when the vehicle starts turning to when the vehicle reaches a stable turning state.

Images