Vehicle control device

Abstract

To suppress a vehicle from deteriorating in a turning performance in a case where a steering device is abnormal, without allowing a structure of the steering device to become more complex.SOLUTION: In a vehicle control apparatus, in a case where a steering device provided to a wheel that is steering wheel cum drive wheel is abnormal, forward-reverse force transmitted to the wheel via a drive shaft is reduced. As a result, forward-reverse force exerted to the wheel makes it hard to steer the wheel and, with self-aligning torque, it is possible for the wheel to follow a progress direction of the vehicle. Thus, it is possible to suppress deterioration of a turning performance of the vehicle in the case of the steering device being abnormal, without allowing a structure of the steering device to become more complex.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle control device provided in a vehicle. [Background technology]

[0002] Patent Document 1 describes a vehicle in which a steering device is provided for each of the front, rear, left, and right wheels. Each of the steering devices installed on the vehicle is provided with two electric motors for steering and two inverters for controlling the electric motors. As a result, if one of the two electric motors is abnormal, that electric motor can be stopped and the other electric motor can continue to operate. In addition, the other electric motor can bring the abnormal wheel to a neutral position (steered angle is 0). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2019-6188 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to suppress the deterioration of the turning performance of a vehicle when an abnormality occurs in the steering device without complicating the structure of the steering device.

[0005] In the vehicle control device according to the present invention, if a steering device provided for a wheel that is both a steered wheel and a drive wheel malfunctions, the longitudinal force transmitted to that wheel via the drive shaft is reduced. As a result, the wheel is less likely to be steered by the longitudinal force acting on the wheel, and the self-aligning torque enables the wheel to follow the direction of travel of the vehicle. In this way, a decrease in vehicle turning performance when the steering device malfunctions can be suppressed without complicating the steering device structure. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a diagram conceptually showing a vehicle equipped with a vehicle control device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a conceptual diagram showing a longitudinal force application device provided in the vehicle. [Figure 3] FIG. 2 is a perspective view showing a steering device provided in the vehicle. [Figure 4] FIG. 2 is a diagram conceptually showing the periphery of the vehicle control device. [Figure 5] 4 is a flowchart showing a longitudinal force control program stored in a storage unit of the vehicle control device. [Figure 6] 1A is a diagram showing the moment acting on the wheel when the steering device is abnormal, and FIG. 1B is a diagram showing the state of the wheel when an in-wheel motor is provided on the drive wheel. [Figure 7] FIG. 2 is a diagram conceptually showing a vehicle other than the vehicle on which the vehicle control device is mounted. [Figure 8] FIG. 2 is a diagram conceptually showing a vehicle other than the vehicle on which the vehicle control device is mounted. DETAILED DESCRIPTION OF THE INVENTION

[0007] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle control device according to an embodiment of the present invention will now be described with reference to the accompanying drawings. [Example]

[0008] 1 and 2, the vehicle control device according to this embodiment is mounted on a four-wheel drive vehicle including a left front wheel 10FL (the left drive wheel) on one side of the front and rear wheels, a right front wheel 10FR (the right drive wheel) on one side of the front wheels, a left rear wheel 12RL (the left drive wheel) on the other side, and a right rear wheel 12RR (the right drive wheel) on the other side. The four-wheel drive vehicle has an engine 14 (the drive source) mounted on the rear wheels, and is switchable by control of a transfer 30 or the like between a four-wheel drive state in which the drive force of the engine 14 is transmitted to the left and right front wheels 10FL, 10FR and the left and right rear wheels 12RL, 12RR, and a rear-wheel drive state (two-wheel drive state) in which the drive force of the engine 14 is transmitted to the left and right rear wheels 12RL, 12RR but not to the left and right front wheels 10FL, 10FR. The left and right front wheels 10FL, 10FR are also steered wheels, and are provided with steering devices 16FL, 16FR, respectively. Hereinafter, when referring to left and right front wheels, left and right rear wheels, steering devices, etc. collectively, the symbols FL, FR, RL, RR, etc. indicating wheel positions may be omitted if there is no need to distinguish between them by wheel position.

[0009] This four-wheel drive vehicle includes an engine 14 and a longitudinal force applying device 18 that is a device that transmits longitudinal forces, which are driving forces generated by the engine 14 (hereinafter sometimes abbreviated as longitudinal forces of the engine 14), to the drive wheels 10, 12. The longitudinal force applying device 18 includes the engine 14, a main transmission path 20 that transmits the longitudinal forces of the engine 14 to the left and right rear wheels 12, and a secondary transmission path 22 that transmits the longitudinal forces of the engine 14 to the left and right front wheels 10. The main transmission path 20 includes a transmission 24 connected to the engine 14, a rear wheel front / rear force distribution unit 26, and drive shafts 28RL, 28RR connected to the left and right rear wheels 12. The secondary transmission path 22 includes the transmission 24, a transfer 30, a propeller shaft 32, a front wheel front / rear force distribution unit 34, and drive shafts 36FL, 36FR connected to the left and right front wheels 10.

[0010] The transmission 24 reduces the rotational speed of the engine 14. The rear wheel front / rear force distribution unit 26 includes a differential gear mechanism, and distributes the front / rear force of the engine 14 input via the transmission 24 to the left rear wheel 12RL and the right rear wheel 12RR, while allowing a difference in rotational speed between them.

[0011] The transfer 30 distributes the front and rear force of the engine 14 to the front wheels 10. The transfer 30 includes an upstream rotating member 42 connected to a differential case 40, which is the case of the differential gear mechanism of the rear wheel front / rear force distribution unit 26, a downstream rotating member 48 formed with a ring gear 46 that meshes with a driven pinion 44 provided at the rear wheel side end of the propeller shaft 32, and a first clutch 50 that selectively connects and disconnects power transmission between the upstream rotating member 42 and the downstream rotating member 48.

[0012] Outer peripheral teeth 42a that can mesh with inner peripheral teeth 52a of the movable sleeve 52 of the first clutch 50 are formed on the end of the upstream rotating member 42 opposite to the end that is connected to the differential case 40 so as to be rotatable integrally with the first clutch 50. Outer peripheral teeth 48a that can mesh with the inner peripheral teeth 52a of the movable sleeve 52 are formed on the end of the downstream rotating member 48 opposite to the end where the ring gear 46 is formed.

[0013] The first clutch 50 is a meshing dog clutch and includes the outer peripheral teeth 42a formed on the upstream rotating member 42, the outer peripheral teeth 48a formed on the downstream rotating member 48, the inner peripheral teeth 52a of the movable sleeve 52, and an actuator 60 that moves the movable sleeve 52. The actuator 60 is operated by supplying electric power, and moves the movable sleeve 52 in the vehicle width direction (the direction parallel to the drive shaft 28), thereby switching the movable sleeve 52 between an engaged position where it meshes with both the upstream rotating member 42 and the downstream rotating member 48, and a disengaged position where it meshes with the upstream rotating member 42 but does not mesh with the downstream rotating member 48.

[0014] The front-wheel longitudinal force distribution unit 34 distributes the longitudinal force of the engine 14 input via the propeller shaft 32 to the left and right front wheels 10, and also allows for a difference in rotational speed between the drive shafts 36FL, 36FR of the left and right front wheels 10. The front-wheel longitudinal force distribution unit 34 includes a differential gear mechanism 62 and a mesh-type second clutch 64 that selectively connects and disconnects power transmission between the differential gear mechanism 62 and the propeller shaft 32. The longitudinal force distributed by the transfer 30 is transmitted to the differential gear mechanism 62 via the propeller shaft 32 and the second clutch 64.

[0015] The front-wheel front-rear force distribution unit 34 includes an upstream rotating member 76 having, at one end, a ring gear 71 formed thereon that meshes with a driven pinion 70 provided at the front-wheel end of the propeller shaft 32, and at the other end, outer peripheral teeth 76a formed thereon that can mesh with inner peripheral teeth 72a formed on the inner peripheral surface of a movable sleeve 72 of the second clutch 64, and a downstream rotating member 78 that can rotate integrally with a differential case 75 of the differential gear mechanism 62 and has, at one end, outer peripheral teeth 78a formed thereon that can mesh with the inner peripheral teeth 72a of the movable sleeve 72. The second clutch 64 includes, for example, the outer peripheral teeth 76a of the upstream rotating member 76, the outer peripheral teeth 78a of the downstream rotating member 78, the inner peripheral teeth 72a of the movable sleeve 72, and an actuator 80 that moves the movable sleeve 72 in the vehicle width direction (a direction parallel to the drive shaft 36). In the second clutch 64, the movable sleeve 72 is moved by the actuator 80 and switched between an engaged position in which it engages with both the upstream rotating member 76 and the downstream rotating member 78, and a disengaged position in which it does not engage with the upstream rotating member 76 but engages with the downstream rotating member 78, thereby selectively connecting and disconnecting power transmission between the upstream rotating member 76 and the downstream rotating member 78.

[0016] In this way, when the first clutch 50 and the second clutch 64 are engaged, a four-wheel drive state is established in which the longitudinal force of the engine 14 is transmitted to the rear wheels 12 and the front wheels 10. When the first clutch 50 and the second clutch 64 are disengaged, a two-wheel drive state is established in which the longitudinal force of the engine 14 is transmitted to the rear wheels 12 but not to the front wheels 10.

[0017] Since steering devices 16FL, 16FR provided on left and right front wheels 10FL, 10FR respectively have the same structure, only steering device 16FR will be described and a description of steering device 16FL will be omitted. As shown in Fig. 3, wheel 10FR is rotatably held by knuckle 110, to which lower arm 118 is provided via connecting portion 112. Turning device 16FR includes a steering actuator 124 provided on lower arm 118, a pitman arm 134 connected to an output shaft (not shown) of steering actuator 124, and a tie rod 126 connecting pitman arm 134 to knuckle arm 122 of knuckle 110.

[0018] The steering actuator 124 includes a steering motor 130, which is an electric motor serving as a drive source, and a reducer that reduces the rotation of the steering motor 130, and a pitman arm 134 is connected at one end to the output shaft of the reducer, which is the output shaft of the steering actuator 124, so as to be rotatable integrally therewith.

[0019] The other end of the pitman arm 134 is connected to one end of the tie rod 126 via a connecting portion 136. The other end of the tie rod 126 is connected to the knuckle arm 122 via a connecting portion 138.

[0020] In this steering device 16, when steering actuator 124 is driven in the direction indicated by arrow X in Fig. 3, pitman arm 134 is rotated about the axis of steering actuator 124. As pitman arm 134 rotates, tie rod 126 is moved in the direction indicated by arrow Y, whereby knuckle arm 122 and knuckle 110 are rotated about kingpin axis KP, and wheel 10 is steered in the direction indicated by arrow Z. Kingpin axis KP extends on a line connecting an attachment portion of a shock absorber attached to the knuckle to the vehicle body and a connecting portion 112 with lower arm 118.

[0021] In addition, the steering actuator 124 is provided with a rotation speed sensor 140 (see FIG. 4) that detects the rotation speed of the electric motor 130, and a control circuit (not shown) that controls the steering actuator 124 is provided with a current sensor 142 that detects the current flowing through the electric motor 130.

[0022] As shown in Fig. 4, the present vehicle control device includes a vehicle control ECU 150, which is mainly a computer. Connected to vehicle control ECU 150 are a steering operation amount sensor 152 that detects the amount of operation of a steering operation member (not shown), a surrounding information acquisition device 154 that recognizes objects present in the vicinity of the host vehicle (this vehicle) and acquires information indicating the relative positional relationship between the object and the host vehicle, an accelerator opening sensor 156 that detects the amount of operation of an accelerator operation member (not shown), a change-over switch 158, and the like. Also connected to vehicle control ECU 150 are steering actuator 124 of steering device 16, engine 14 of longitudinal force application device 18, transfer 30 (first clutch 50), second clutch 64, and the like. Change-over switch 158 can be manually operated by the driver and is a switch that instructs switching between four-wheel drive mode and two-wheel drive mode.

[0023] In the vehicle control ECU 150 configured as described above, a target steering angle is acquired based on at least one of the amount of operation of the steering operation member detected by the steering operation amount sensor 152 and the relative positional relationship between the vehicle and surrounding objects acquired by the surrounding information acquisition device 154, and the steering actuators 124 of the steering devices 16FL, 16FR are controlled so that the target steering angle is realized. In addition, the engine 14 is controlled based on at least one of the operation state of the accelerator operating member detected by the accelerator opening sensor 156 and the relative positional relationship between the vehicle and surrounding objects acquired by the surrounding information acquisition device 154. Furthermore, the transfer case 30 and other components are controlled based on the instruction state of the change-over switch 158, and the vehicle is switched between four-wheel drive and two-wheel drive.

[0024] Furthermore, it is determined whether left-side steering device 16FL and right-side steering device 16FR provided on left front wheel 10FL and right front wheel 10FR are abnormal, and if abnormal, the abnormal steering device 16 is stopped. However, because left and right front wheels 10 are steered wheels and also drive wheels, in a four-wheel drive state, a longitudinal force (driving force in this embodiment) F is transmitted to left and right front wheels 10 via drive shaft 36. In this case, as shown in FIG. 6(a), longitudinal force F acts on ground contact point S of front wheel 10 (more specifically, the ground contact point of the tire, located approximately in the center in the tire width direction), but intersection P of kingpin axis KP and the road surface is located a distance d from ground contact point S of front wheel 10. Therefore, a moment M is generated around intersection P of kingpin axis KP and the road surface by longitudinal force F, which may cause front wheel 10 to be steered.

[0025] More specifically, as shown in FIG. 6( a), when a longitudinal force F is applied to the drive wheel 10 via the drive shaft 36, a reaction force Fa of the longitudinal force F acting on the ground contact point S is received by a portion of the vehicle body member above the knuckle 110 (a reaction force Fb). In other words, the longitudinal force F acting on the ground contact point S of the front wheel 10 and the reaction force Fb on the vehicle body member are located on opposite sides of the kingpin axis KP in both the width direction and the up-down direction of the vehicle. Therefore, the longitudinal force F acting on the ground contact point S of the tire generates a moment M about the kingpin axis KP, and the right front wheel 10FR may be steered by the longitudinal force. This moment M is greater than self-aligning torque (when a tire is given a slip angle and caused to roll, a torque is generated in the tire about the vertical axis due to cornering force in a direction that reduces the slip angle. This torque is called self-aligning torque). As a result, the steering angle of the right front wheel 10FR becomes larger, reducing the vehicle's turning ability.

[0026] On the other hand, if an in-wheel motor is provided on a driving wheel that is a front wheel, as shown in Figure 6(b), the longitudinal force F applied to the wheel by the in-wheel motor acts on the contact point of the tire, but the reaction force Fa of the longitudinal force F is received at a portion inside the wheel below the knuckle (reaction force Fb). Therefore, the longitudinal force F and the reaction force Fb are located on the same side of the kingpin axis KP, making it difficult for a moment to be generated around the kingpin axis KP and making it difficult for the front wheel 10 to turn.

[0027] In the vehicle control ECU 150, a longitudinal force control program shown in the flowchart of FIG. 5 is executed at predetermined set time intervals. In step 1 (hereinafter simply referred to as S1, and the same applies to the other steps), it is determined whether or not each of left and right steering devices 16FL, 16FR is abnormal. For example, if the current flowing through steering actuator 124 is smaller than the set current due to a broken wire, a battery abnormality, etc., or if the actual steering angle determined by the rotation speed of electric motor 30 is smaller than the target steering angle, it can be considered that an abnormality has occurred. The presence or absence of an abnormality in steering device 16 is detected based on the detection values of rotation speed sensor 140, current sensor 142, etc.

[0028] If either one of the steering devices 16FL, 16FR (for example, the right-side steering device 16FR) is abnormal and the determination in S1 is YES, the right-side steering device 16FR is stopped in S2. Then, in S3 and S4, the vehicle is switched to a rear-wheel drive state by controlling the transfer 30, etc. This allows the longitudinal force applied to the front wheels 10 to be reduced and the longitudinal force applied to the rear wheels 12 to be increased.

[0029] In this way, if the right steering device 16FR is abnormal, the right steering device 16FR is stopped, but the left steering device 16FL is normal and therefore in operation. The left front wheel 10FL is steered by the steering device 16FL, and the vehicle is able to turn in that steering direction. Furthermore, because the right-side steering device 16FR is abnormal, the longitudinal force transmitted to the right front wheel 10FR is reduced. As a result, the longitudinal force transmitted to the right front wheel 10FR makes it difficult for the right front wheel 10FR to be turned significantly. The self-aligning torque acting on the right front wheel 10FR makes it possible for the right front wheel 10FR to follow the direction of travel of the vehicle, thereby suppressing a decrease in the vehicle's turning ability.

[0030] In this way, in this embodiment, it is possible to effectively suppress a decrease in the turning performance of the vehicle without complicating the structure of the steering device 16 by providing two electric motors 130 or the like. In addition, since the longitudinal forces transmitted to the left and right front wheels 10 are reduced while the longitudinal forces transmitted to the left and right rear wheels 12 are increased, the reduction in longitudinal forces of the entire vehicle can be effectively suppressed.

[0031] As described above, in this embodiment, the abnormality detection device is configured by current sensor 142, a part of vehicle control ECU 150 that stores S1, a part that executes S1, etc., the longitudinal force control unit is configured by a part that stores S3 and S4, a part that executes S1, etc., and the steering control unit is configured by a part that stores S2, a part that executes S2, etc.

[0032] In the above embodiment, the driving source is the engine 14, but it may also include an electric motor. An example of this case is shown in FIG. In the front-rear force application device 198 provided on this vehicle, electric motors 200F, 200R are provided as drive sources on the front and rear wheels, respectively. Electric motor 200F is connected to left and right front wheels 10FL, 10FR via a transmission 202F, a front-wheel front-rear force distribution unit 204F, and drive shafts 206FL, 206FR. An inverter 214F is provided between electric motor 200F and battery 212, and the operating state of electric motor 200F is controlled by inverter 214F. Inverter 214F switches between a state in which electric power from battery 212 is supplied to electric motor 200F and a state in which electric power generated by electric motor 200F is charged to battery 212, thereby generating regenerative braking force. Front-wheel front-rear force distribution unit 204F may include, for example, a differential gear mechanism similar to the differential gear mechanism included in front-wheel front-rear force distribution unit 34 in the above-described embodiment.

[0033] The same is true for the rear wheels, where electric motor 200R is connected to left and right rear wheels 12RL, 12RR via transmission 202R, rear wheel front / rear force distribution unit 204R, and drive shafts 206RL, 206RR, respectively. In addition, an inverter 214R is provided between electric motor 200R and battery 212. Inverter 214R switches electric motor 200R between a state in which electric power from battery 212 is supplied to electric motor 200R, and a state in which electric power generated in electric motor 200R is charged into battery 212, thereby generating regenerative braking force. In this embodiment, battery 212 is provided in common to electric motor 200F on the front wheels and electric motor 200R on the rear wheels.

[0034] Furthermore, in this vehicle, friction brakes 220FL, 220FR, 220RL, and 220RR are provided corresponding to the left and right front wheels 10 and the left and right rear wheels 12, respectively. The friction brakes 220 frictionally engage friction engagement members with brake rotors that can rotate integrally with the left and right front wheels 10 and the left and right rear wheels 12, respectively, thereby suppressing rotation of the left and right front wheels 10 and the left and right rear wheels 12. The friction brakes 220 can be operated by hydraulic pressure or by an electric motor, for example.

[0035] Furthermore, in this vehicle, steering devices 16FL, 16FR, 16RL, 16RR having the same structure as steering device 16 in the above embodiment are provided corresponding to left and right front wheels 10 and left and right rear wheels 12. In this vehicle, the four wheels 10, 12 (front, rear, left and right) are steered wheels.

[0036] In a vehicle configured as described above, a driving force or braking force (regenerative braking force) serving as a longitudinal force is applied to each of the wheels 10, 12 by the longitudinal force application device 198. Furthermore, for example, if a steering device 16FR provided on the right front wheel 10FR is abnormal, the steering device 16FR is stopped, and the longitudinal force output by the electric motor 200F is reduced by the inverter 214F. This reduces the longitudinal force applied to the left and right front wheels 10, making it difficult for the right front wheel 10FR to be steered by the longitudinal force, thereby reducing the turning ability of the vehicle. Furthermore, on the rear wheel side, the longitudinal force output by the electric motor 200R is increased by the inverter 214R. This increases the longitudinal force applied to the left and right rear wheels 12, suppressing a decrease in the longitudinal force of the entire vehicle.

[0037] Furthermore, if the steering device 16FR is detected to be abnormal while the longitudinal force application device 198 is applying a regenerative braking force, which is a longitudinal force, it is possible to reduce the regenerative braking force applied to the front wheels 10, while increasing the braking force of the friction brakes 220 of the front wheels 10 (including the case where the friction brakes 220 are newly activated). In this case, there is little need to increase the regenerative braking force applied to the rear wheels 12.

[0038] 8, longitudinal force application device 228 can include in-wheel motors 230RL, 230RR as drive sources provided for left and right rear wheels 12, respectively. Also, a single steering device can be provided commonly for left and right rear wheels 12. Left and right rear wheels 12 are connected via knuckle arms, tie rods 240L, 240R, and steering shaft 242, and steering device 250 is provided on steering shaft 242, which moves steering shaft 242 in the width direction to steer left and right rear wheels 12.

[0039] In the vehicle configured as described above, if the steering device 16FR of the right front wheel 10FR is abnormal, the longitudinal forces (driving force or regenerative braking force in this embodiment) applied to the left and right front wheels 10 are reduced. This makes it possible to suppress a decrease in the turning performance of the vehicle. Additionally, as the longitudinal force applied to the front wheels 10 decreases, the longitudinal force applied to the rear wheels 12 is increased by controlling the in-wheel motors 230 provided on each of the left and right rear wheels 12. This makes it possible to suppress the decrease in longitudinal force of the entire vehicle.

[0040] On the other hand, when the steering device 250 is abnormal, there is little need to reduce the longitudinal forces applied by the in-wheel motors 230 to the left and right rear wheels 12. This is because, as described above, the rear wheels 12 are difficult to turn due to the longitudinal forces applied by the in-wheel motors 230.

[0041] The vehicle may be an internal combustion engine vehicle whose drive source includes an engine, a hybrid vehicle, an electric vehicle whose drive source includes an electric motor, or the like. 2, 7, and 8. For example, the number of steered wheels may be two, i.e., front left and right wheels or rear left and right wheels, or four, i.e., front left and right wheels, and in the case where the number of steered wheels is four, it is possible to provide steering device 250 on at least one of the front and rear wheels, or to provide steering device 16 on each of front left and right wheels 10, 12. Furthermore, a drive source can be provided by connecting the left and right wheels on at least one of the front and rear wheels with a drive shaft. Also, an in-wheel motor can be provided for each of the left and right wheels on either the front or rear wheel side.

[0042] Furthermore, the present invention can be implemented in various forms with various modifications and improvements made based on the knowledge of those skilled in the art. [Explanation of symbols]

[0043] 10: Front wheel 12: Rear wheel 14: Engine 16: Steering device 18,198: Longitudinal force imparting device 28,36: Drive shaft 30: Transfer 50: First clutch 64: Second clutch 124: Steering actuator 126: Tie rod 150: Vehicle control ECU 200: Drive source 214: Inverter 212: Battery 206: Drive shaft 230: In-wheel motor 250: Steering device Patentable invention

[0044] The following paragraphs describe patentable inventions: (1) The left and right wheels on either the front or rear side of the vehicle are both drive and steerable wheels, a steering device provided on each of the left steering wheel and the right steering wheel, the steering device configured to steer the steering wheel; a longitudinal force applying device that applies longitudinal forces, which are driving forces or braking forces, to each of the left drive wheel that is the left drive wheel and the right drive wheel that is the right drive wheel via a drive shaft; provided in a vehicle including an abnormality detection device that detects the presence or absence of an abnormality in each of the left steering device that is the steering device provided on the left steering wheel and the right steering device that is the steering device provided on the right steering wheel; a longitudinal force control unit that reduces the longitudinal force applied to at least one of the left driving wheel and the right driving wheel by controlling the longitudinal force application device when the abnormality detection device detects that at least one of the left steering device and the right steering device is abnormal; A vehicle control device including:

[0045] The longitudinal force applying device may be, for example, a device that includes a drive source and transmits longitudinal forces generated by the drive source to the left drive wheel and the right drive wheel. The drive source may include an engine or an electric motor. The longitudinal force control section reduces the longitudinal force and can also reduce the longitudinal force to zero.

[0046] (2) Both the left and right wheels on the other side of the front and rear wheels of the vehicle are drive wheels, the longitudinal force applying device applies the longitudinal force to a left drive wheel that is the drive wheel on the left side belonging to the other side and a right drive wheel that is the drive wheel on the right side, The vehicle control device described in (1), wherein the longitudinal force control unit reduces the longitudinal force applied to at least one of the left drive wheel and the right drive wheel belonging to either one of the sides, and increases the longitudinal force applied to at least one of the left drive wheel and the right drive wheel belonging to the other side.

[0047] (3) The vehicle control device described in (2), wherein the longitudinal force applying device includes in-wheel motors as drive sources provided corresponding to the left drive wheel and the right drive wheel belonging to the other side, respectively.

[0048] (4) The vehicle control device according to (2), wherein the longitudinal force applying device applies the longitudinal force to each of the left drive wheel and the right drive wheel belonging to the other side via a drive shaft.

[0049] The longitudinal force applying device may include one drive source or may include two or more drive sources.

[0050] (5) The left wheel and the right wheel belonging to the other side of the vehicle are both steered wheels, The vehicle control device according to any one of (1) to (4), wherein the vehicle includes one or more steering devices that steer the left steering wheel and the right steering wheel.

[0051] In this embodiment, four wheels are steered. In this case, the left and right steered wheels on the other side are connected in the width direction via tie rods and a steering shaft, and a steering device can be provided on the steering shaft.

[0052] (6) A vehicle control device according to any one of items (1) to (5), wherein the vehicle control device includes a steering control unit that stops the abnormal steering device when the abnormality detection device detects that the at least one steering device is abnormal.

Claims

1. Both the left and right wheels on either the front or rear side of the vehicle are drive and steerable wheels, a steering device provided on each of the left steering wheel and the right steering wheel, the steering device configured to steer the steering wheel; a longitudinal force application device that applies a longitudinal force, which is a driving force or a braking force, to each of the left drive wheel that is the left drive wheel and the right drive wheel that is the right drive wheel via a drive shaft, an abnormality detection device that detects the presence or absence of an abnormality in each of the left steering device, which is the steering device provided on the left steering wheel, and the right steering device, which is the steering device provided on the right steering wheel; a steering control unit that stops at least one of the left steering device and the right steering device that has been detected as being abnormal when the abnormality detection device detects that at least one of the left steering device and the right steering device is abnormal; a longitudinal force control unit that, when the abnormality detection device detects that at least one of the left steering device and the right steering device is abnormal, controls the longitudinal force applying device to reduce both the longitudinal force applied to the left drive wheel and the longitudinal force applied to the right drive wheel.

2. Both the left and right wheels on either the front or rear side of the vehicle are drive and steerable wheels, the left and right wheels belonging to the other of the front and rear wheel sides are both drive wheels, a steering device provided on each of the left and right steering wheels belonging to either one of the two sides, for steering the steering wheels; a longitudinal force applying device that applies a longitudinal force, which is a driving force or a braking force, to each of a left drive wheel that is the drive wheel on the left side and a right drive wheel that is the drive wheel on the right side, via a drive shaft, and that applies the longitudinal force to each of a left drive wheel that is the drive wheel on the left side and a right drive wheel that is the drive wheel on the right side, which belong to the other side, an abnormality detection device that detects the presence or absence of an abnormality in each of the left steering device, which is the steering device provided on the left steering wheel, and the right steering device, which is the steering device provided on the right steering wheel; a steering control unit that stops at least one of the left steering device and the right steering device that has been detected as being abnormal when the abnormality detection device detects that at least one of the left steering device and the right steering device is abnormal; When the abnormality detection device detects that at least one of the left-side steering device and the right-side steering device is abnormal, the vehicle control device controls the longitudinal force applying device to reduce the longitudinal force applied to at least one of the left-side drive wheel and the right-side drive wheel belonging to one of the sides, and to increase the longitudinal force applied to at least one of the left-side drive wheel and the right-side drive wheel belonging to the other side.

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