Vehicle control device

Abstract

The invention provides a vehicle control device capable of performing torque control corresponding to curve travel. A vehicle control device according to one embodiment of the present disclosure is provided with a control unit that derives a target torque for each wheel by adding a fluctuating torque for each wheel, which fluctuates periodically, to a requested torque for each wheel in response to an accelerator opening degree. And torque-controlling each motor on the basis of the derived target torque for each wheel. When a turning of the vehicle is detected, the control means is capable of setting a first gain of the fluctuating torque applied to each of the motors on the outer wheel side to a value greater than a second gain of the fluctuating torque applied to each of the motors on the inner wheel side.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a vehicle control device mounted on a vehicle. BACKGROUND

[0002] In the past, various techniques for more safely operating a vehicle have been proposed (for example, refer to Patent Documents 1 to 3).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2010-074947

[0004] Patent Document 2: International Publication No. WO2002 / 000463

[0005] Patent Document 3: Japanese Patent Application Publication No. 2011-205799 SUMMARY

[0006] The vehicle control device of one embodiment of the present disclosure is capable of controlling a vehicle that has four wheels and four motors each provided to each wheel, and that is capable of traveling by independently driving each motor. The vehicle control device has a control unit that derives a target torque of each wheel by adding a fluctuation torque of each wheel that fluctuates periodically to a requested torque of each wheel in response to an accelerator opening degree, and that performs torque control of each motor based on the derived target torque of each wheel. The control unit is capable of setting a first gain of the fluctuation torque applied to each motor on an outer wheel side to a value larger than a second gain of the fluctuation torque applied to each motor on an inner wheel side, in a case where a turning of the vehicle is detected. BRIEF DESCRIPTION OF DRAWINGS

[0007] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate an embodiment, and together with the specification serve to explain principles of the present disclosure.

[0008] Figure 1 is a drawing illustrating one example of a functional block of a vehicle of one embodiment of the present disclosure.

[0009] Figure 2 is a drawing illustrating one example of a configuration of four wheels and four motors of a vehicle provided with Figure 1 .

[0010] Figure 3 is a drawing illustrating a modified example of a configuration of four wheels and four motors of a vehicle provided with Figure 1 .

[0011] Figure 4 (A) of FIG. 4 is a drawing illustrating one example of a waveform of a requested torque. Figure 4 (B) of FIG. 4 is a drawing illustrating one example of a waveform of a fluctuation torque. Figure 4(C) is a diagram showing an example of the waveform of the target torque.

[0012] Figure 5 This is a diagram illustrating an example of the waveform of the varying torque of each wheel during a left turn.

[0013] Figure 6 This is a diagram illustrating an example of the waveform of the varying torque of each wheel during a right turn.

[0014] Figure 7 It is shown Figure 1 A diagram illustrating an example of the steps involved in deriving the target torque for a vehicle.

[0015] Figure 8 It shows the continuation Figure 6 A diagram illustrating an example of the steps.

[0016] Figure 9 It is shown Figure 1 A diagram of a variant of the functional blocks of a vehicle.

[0017] Figure 10 It is shown Figure 9 A diagram of an example of a road surface on which a vehicle travels.

[0018] Figure 11 It is shown Figure 9 A diagram illustrating an example of the steps for deriving the variable torque gain of a vehicle.

[0019] (Explanation of reference numerals in the attached diagram)

[0020] 1...Vehicle, 10...Sensor Unit, 11...Throttle Opening Sensor, 12...Vehicle Status Sensor, 13...Road Status Sensor, 20...Storage Unit, 21...Control Flag, 30...Control Unit, 31...Driving Control Unit, 32...Request Torque Derivation Unit, 33...Variable Torque Derivation Unit, 34...Motor Torque Control Unit, 35...Road μ Calculation Unit, 40...Control Flag Input Unit, 50...Motor, G, G1, G2, G3...Variable Torque Gain, M_FL...Left Front Wheel Motor, M_FR...Right Front Wheel Motor, M_RL... …Left rear wheel motor, M_RR……Right rear wheel motor, s……Slip rate, Tf0……Base torque, Tf_FL……Left front wheel variable torque, Tf_FR……Right front wheel variable torque, Tf_RL……Left rear wheel variable torque, Tf_RR……Right rear wheel variable torque, Tf……Variable torque, Tg_FL……Left front wheel target torque, Tg_FR……Right front wheel target torque, Tg_RL……Left rear wheel target torque, Tg_RR……Right rear wheel target torque, Tg……Target torque, α……Low μ region, β……High μ region, ΔG1, ΔG2……Additional gain. DETAILED DESCRIPTION

[0021] <1. Background>

[0022] In a vehicle that travels by motor drive, the motor output is smooth compared to the engine output. Therefore, a smooth feeling of operation is obtained in all traveling states such as straight traveling, traveling lane change, curved road traveling. However, while such a feeling of operation is obtained, the information (driver information) received by the driver from the vehicle is small. In rainy weather or on a low friction coefficient road (low μ road) such as a snowy road or an icy road, the grip of the vehicle is reduced, so the driver information is smaller than in dry weather. Therefore, it is difficult for the driver to grasp the road surface condition and the grip of the vehicle. As a result, there is a problem that the slip limit of the tire is easily exceeded, and slip occurs, thereby causing the vehicle to spin or the vehicle to understeer.

[0023] In order to improve the driver information for such a problem, it is considered that a target torque is derived by adding a fluctuation torque that fluctuates periodically to a request torque that responds to an acceleration request, and the torque of the motor is controlled based on the derived target torque (for example, refer to Patent Documents 1 to 3). However, such a request for torque control differs in response to the traveling state. In particular, when traveling on a curved road, the work of the vehicle is greatly different from that when traveling on a straight road, so torque control that responds to curved road traveling is sought. It is desirable to provide a vehicle control device that can perform torque control that responds to curved road traveling.

[0024] Hereinafter, some example embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Furthermore, the following description shows a specific example of the present disclosure, and cannot be interpreted as limiting the present disclosure. For example, each element including a numerical value, a shape, a material, a component, a position of each component, and a connection method of each component and the like is merely an example, and cannot be interpreted as limiting the present disclosure. In addition, in the following example embodiments, a configuration element not described in an independent item based on the highest concept of the present disclosure is arbitrary, and can be provided as needed. The drawings are schematic drawings, and are not intended to be drawn to scale. Throughout the present specification and the drawings, for configuration elements having substantially the same function and substantially the same structure, the same reference numerals are assigned, and redundant description is omitted. In addition, a configuration element not directly related to an embodiment of the present disclosure is not illustrated in the drawings.

[0025] <2. Embodiment>

[0026] [Structural Example]

[0027] A structural example of the control unit 30 and the vehicle 1 of an embodiment of the present disclosure will be described. Figure 1is a diagram showing one example of a functional block of the vehicle 1 of the present embodiment. The vehicle 1 is capable of traveling by independent driving of four motors each of which is provided to each steering wheel. For example, as shown in Figure 1 the vehicle 1 has a sensor section 10, a storage section 20, a control unit 30, a control flag input section 40, and a motor 50. The control unit 30 corresponds to one specific example of the "vehicle control device", "control unit" of the present embodiment of the present disclosure.

[0028] The motor 50 is configured to drive each steering wheel of the vehicle 1. The motor 50 is capable of independently driving each steering wheel of the vehicle 1 in accordance with a target torque Tg of each steering wheel input from a motor torque control section 34 (described later). The vehicle 1 is provided with four steering wheels. As shown in Figure 2 two front wheels (a left front wheel T_FL, a right front wheel T_FR) and two rear wheels (a left rear wheel T_RL, a right rear wheel T_RR) are provided to the vehicle 1 as the four steering wheels. The motor 50 includes a left front wheel motor M_FL provided to the left front wheel T_FL, a right front wheel motor M_FR provided to the right front wheel T_FR, a left rear wheel motor M_RL provided to the left rear wheel T_RL, and a right rear wheel motor M_RR provided to the right rear wheel T_RR. Hereinafter, the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR are collectively referred to as a motor M. In addition, the left front wheel T_FL, the right front wheel T_FR, the left rear wheel T_RL, and the right rear wheel T_RR are collectively referred to as a wheel T.

[0029] For example, as shown in Figure 2 the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR are in-wheel motors provided inside the left front wheel T_FL, the right front wheel T_FR, the left rear wheel T_RL, and the right rear wheel T_RR. For example, as shown in Figure 3 the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR can also be motors linked to the left front wheel T_FL, the right front wheel T_FR, the left rear wheel T_RL, and the right rear wheel T_RR via drive shafts DS_FL, DS_FR, DS_RL, and DS_RR.

[0030] The sensor section 10 includes various sensors mounted on the vehicle 1. For example, as shown in Figure 1 the sensor section 10 has a throttle opening degree sensor 11 and a vehicle state quantity sensor 12. The sensor section 10 can have sensors other than the above.

[0031] The throttle opening degree sensor 11 is capable of detecting a throttle opening degree from a depression amount of a throttle pedal. The throttle opening degree sensor 11 is capable of outputting data of the detected throttle opening degree (throttle opening degree data) to the control unit 30.

[0032] The vehicle state quantity sensor 12 is capable of detecting a vehicle state quantity that indicates a state of the vehicle 1. The vehicle state quantity sensor 12 is capable of outputting time-series data of the detected vehicle state quantity (vehicle state quantity data) to the control unit 30. The vehicle state quantity sensor 12 includes, for example, a vehicle speed sensor, an acceleration sensor, an angular velocity sensor, a steering angle sensor, a steering torque sensor, and a load sensor as sensors capable of detecting a vehicle state quantity.

[0033] The vehicle speed sensor is capable of detecting a speed of the vehicle 1 (vehicle speed). The vehicle speed sensor is capable of outputting time-series data of the detected vehicle speed (vehicle speed data) to the control unit 30. The acceleration sensor is capable of detecting accelerations applied to the vehicle 1. The acceleration sensor is capable of outputting time-series data of the detected three-directional accelerations (forward-backward acceleration, left-right acceleration (lateral acceleration), up-down acceleration) (acceleration data) to the control unit 30. The angular velocity sensor is capable of detecting angular velocities of the vehicle 1. The angular velocity sensor is capable of outputting time-series data of the detected three angular velocities (yaw angular velocity (yaw rate), roll angular velocity, pitch angular velocity) (angular velocity data) to the control unit 30.

[0034] The steering angle sensor is capable of detecting a steering angle of a steering wheel of the vehicle 1 (steering wheel steering angle). The steering angle sensor is capable of outputting time-series data of the detected steering wheel steering angle (steering wheel steering angle data) to the control unit 30. The steering torque sensor is capable of detecting a steering torque generated by a handle operation of a driver. The steering torque sensor is capable of outputting time-series data of the detected steering torque (steering torque data) to the control unit 30. The load sensor is capable of detecting a load generated at each wheel T. The load sensor is capable of outputting time-series data of the detected load (load data) to the control unit 30.

[0035] The control flag 21 is stored in the storage 20, for example, which is input from the control flag input 40. The control flag 21 includes an identifier indicating which of the travel modes is the "torque fluctuation control mode" and the "normal mode". The "torque fluctuation control mode" refers to a mode in which the target torque Tg is vibrated at a low frequency. The "normal mode" refers to a mode in which the target torque Tg is not vibrated at a low frequency, and torque control is performed in response to the requested torque Tr.

[0036] A program executed by the control unit 30 can be stored in the storage 20, for example. The program is a program for causing the control unit 30 to execute a series of steps for controlling the vehicle 1 as a whole. The storage 20 is structured by, for example, a RAM (Random Access Memory), a ROM (Read Only Memory), an auxiliary storage device (hard disk or the like), or the like.

[0037] The control unit 30 is capable of controlling the vehicle 1 as a whole. The control unit 30 is, for example, a so-called ECU (Electronic Control Unit), and includes, for example, one or a plurality of processors and one or a plurality of memories, and the like. The control unit 30 can include, for example, a CPU (Central Processing Unit), and the like. At this time, the control unit 30 can control the vehicle 1 as a whole by executing a program stored in the storage 20, for example.

[0038] The control unit 30 is capable of controlling the vehicle 1 that travels by being driven by the motor. For example, as shown in FIG. 1, the control unit 30 has a travel control section 31. The travel control section 31 is capable of controlling travel of the vehicle 1 (for example, torque of the motor 50). For example, as shown in FIG. 2, the travel control section 31 has a request torque derivation section 32, a fluctuation torque derivation section 33, and a motor torque control section 34. Figure 1 Figure 1

[0039] The request torque derivation section 32 is capable of deriving a request torque Tr (refer to (A) of FIG. 3) in response to an acceleration request. The acceleration request refers to a change in the amount of depression of the accelerator pedal or the accelerator pedal. That is, the request torque derivation section 32 is capable of deriving a request torque Tr in response to an accelerator opening degree. Figure 4 One example of a change in the request torque Tr with time when a driver depresses the accelerator pedal at a constant speed with time is shown in (A) of FIG. 3. The acceleration request can be requested by the driver in manual driving, and can be requested by the travel control section 31 in automatic driving. The request torque derivation section 32 is capable of deriving an amount of torque (request torque Tr) that the motor 50 should generate, on the basis of accelerator opening degree data obtained from the accelerator opening degree sensor 11. Figure 4 The fluctuation torque derivation section 33 is capable of deriving a fluctuation torque Tf (refer to (B) of FIG. 4) that fluctuates periodically. The fluctuation torque Tf is a torque that provides driver information to the driver by intentionally changing the operation of the vehicle 1. One example of a change in the fluctuation torque Tf with time is shown in (B) of FIG. 4. The fluctuation torque Tf is represented by a value obtained by multiplying a fluctuation torque gain G by a base torque Tf0. The gain G is, for example, a value greater than 0. The gain G can also be zero (0), for example.

[0040] Figure 4 Figure 4

[0041] ​​​​​The variation range of the variable torque Tf is, for example, a value within the range of several percent to several tens of percent of the magnitude of the requested torque Tr. The frequency of the variable torque Tf (basic torque Tf0) is, for example, a value within the range of 10 Hz to 30 Hz. The waveform of the variable torque Tf (basic torque Tf0) is, for example, a rectangular or sine wave. The variation range, frequency, and waveform of the variable torque Tf are not limited to the specific examples described above. For example, the variable torque derivation unit 24 can change at least one of the variation range, frequency, and waveform of the basic torque Tf0 in response to the magnitude of the requested torque Tr. The variable torque derivation unit 24 can, for example, keep at least one of the variation range, frequency, and waveform of the basic torque Tf0 constant regardless of the magnitude of the requested torque Tr.

[0042] The variable torque derivation unit 33 can detect whether the vehicle 1 is turning based on data obtained from the vehicle state quantity sensor 12. The variable torque derivation unit 33 can detect whether the vehicle 1 is turning based on at least one of the following values: steering wheel angle, front-to-back acceleration, lateral acceleration, and yaw rate. When turning is detected, the variable torque derivation unit 33 can set the gain of the variable torque Tf applied to each motor M on the outer wheel side to a value greater than the gain of the variable torque Tf applied to each motor M on the inner wheel side. The gain of the variable torque Tf applied to each motor M on the outer wheel side corresponds to a specific example of the "first gain" in one embodiment of this disclosure. Hereinafter, the gain of the variable torque Tf applied to each motor M on the outer wheel side will be referred to as the variable torque gain Gout. The gain of the variable torque Tf applied to each motor M on the inner wheel side corresponds to a specific example of the "second gain" in one embodiment of this disclosure. Hereinafter, the gain of the variable torque Tf applied to each motor M on the inner wheel side will be referred to as the variable torque gain Gin. The variable torque gain Gout and the variable torque gain Gin will be described later. Figure 5 (A) to (D) in the middle and the following are... Figure 6 Examples are shown in (A) to (D).

[0043] Figure 5 Figures (A) to (D) are examples of waveforms showing the varying torque Tf of each wheel T during a left turn. Figure 5 Figure (E) is an example diagram showing the waveform of the torque variation control switch being turned on and off. Figure 5 In (A) and (E), t1 refers to when vehicle 1 enters the left corner, that is, when vehicle 1 begins to turn left. t2 refers to when the angular velocity of vehicle 1 becomes constant after entering the left corner, that is, when vehicle 1 reaches a steady state. t3 refers to when vehicle 1 exits the left corner (enters the straight road within the left corner), that is, when the angular velocity of vehicle 1 begins to change again. t4 refers to when vehicle 1 leaves the left corner, that is, when the left turn of vehicle 1 ends. Figure 5In (A) to (D) in FIG. 12, the variable torque gain G1, G2, G3 is one example of a gain of the variable torque Tf applied to the motor M. The variable torque gain G2 is a value larger than the variable torque gain G1. The variable torque gain G3 is a value larger than the variable torque gain G2.

[0044] The variable torque deriving section 33 can set the gain of the variable torque Tf applied to each of the motors M_FL, M_RL on the left front and rear wheel side (variable torque gain Gout) to a value larger than the gain of the variable torque Tf applied to each of the motors M_FR, M_RR on the right front and rear wheel side (variable torque gain Gin) in a case where it is detected that the vehicle 1 is turning left. For example, as shown in (A) to (D) in FIG. 11, the variable torque deriving section 33 can set the variable torque gain Gout to a value larger than the variable torque gain Gin during a period (t1 to t4) in which the vehicle 1 is traveling in a left corner. Figure 5

[0045] Figure 6 (A) to (D) in FIG. 12 are graphs showing one example of a waveform of the variable torque Tf of each wheel T at the time of right turning. Figure 6 (E) in FIG. 12 is a graph showing one example of a waveform of the on-off of the torque variation control operation switch. In (E) in FIG. 12, the on-off of the torque variation control operation switch is shown in a case where the vehicle 1 is turning right. Figure 6 (A) to (E) in FIG. 12, t1 indicates when the vehicle 1 enters a right corner, that is, when the vehicle 1 starts right turning. t2 indicates when the angular velocity of the vehicle 1 becomes constant after the vehicle 1 enters the right corner, that is, when the vehicle 1 becomes steady. t3 indicates when the vehicle 1 exits the right corner (enters a straight road in the right corner), that is, when the angular velocity of the vehicle 1 starts to change again. t4 indicates when the vehicle 1 exits the right corner, that is, when the right turning of the vehicle 1 ends.

[0046] The variable torque deriving section 33 can set the gain of the variable torque Tf applied to each of the motors M_FL, M_RL on the left front and rear wheel side (variable torque gain Gout) to a value larger than the gain of the variable torque Tf applied to each of the motors M_FR, M_RR on the right front and rear wheel side (variable torque gain Gin) in a case where it is detected that the vehicle 1 is turning right. For example, as shown in (A) to (D) in FIG. 12, the variable torque deriving section 33 can set the variable torque gain Gout to a value larger than the variable torque gain Gin during a period (t1 to t4) in which the vehicle 1 is traveling in a right corner. Figure 6

[0047] ​​The variation torque deriving section 33 can set the variation torque gain GFout applied to the motor M on the front wheel side among the motors M on the outer wheel side to a value larger than the variation torque gain GRout applied to the motor M on the rear wheel side among the motors M on the outer wheel side at the time of entering a corner at the start of turning. The variation torque deriving section 33 can set the variation torque gain GRout to a value larger than the variation torque gain GFout at the time of exiting a corner at the end of turning. The variation torque gain GFout corresponds to a specific example of the "third gain" of one embodiment of the present disclosure. The variation torque gain GRout corresponds to a specific example of the "fourth gain" of one embodiment of the present disclosure.

[0048] For example, as shown in (C), (D) of FIG. 12, the variation torque deriving section 33 can set the variation torque gain GFout applied to the right front wheel motor M_FR to a value larger than the variation torque gain GRout applied to the right rear wheel motor M_RR at the time of entering a corner at the start of left turning (t1-t2). For example, as shown in (E), (F) of FIG. 12, the variation torque deriving section 33 can set the variation torque gain GRout to a value larger than the variation torque gain GFout at the time of exiting a corner at the end of left turning (t3-t4). Figure 5 Figure 5 For example, as shown in (C), (D) of FIG. 12, the variation torque deriving section 33 can set the variation torque gain GFout applied to the right front wheel motor M_FR to a value larger than the variation torque gain GRout applied to the right rear wheel motor M_RR at the time of entering a corner at the start of left turning (t1-t2). For example, as shown in (E), (F) of FIG. 12, the variation torque deriving section 33 can set the variation torque gain GRout to a value larger than the variation torque gain GFout at the time of exiting a corner at the end of left turning (t3-t4).

[0049] For example, as shown in (A), (B) of FIG. 11, the variation torque deriving section 33 can set the variation torque gain GFout applied to the left front wheel motor M_FL to a value larger than the variation torque gain GRout applied to the left rear wheel motor M_RL at the time of entering a corner at the start of right turning (t1-t2). For example, as shown in (C), (D) of FIG. 11, the variation torque deriving section 33 can set the variation torque gain GRout to a value larger than the variation torque gain GFout at the time of exiting a corner at the end of right turning (t3-t4). Figure 6 Figure 6 For example, as shown in (A), (B) of FIG. 11, the variation torque deriving section 33 can set the variation torque gain GFout applied to the left front wheel motor M_FL to a value larger than the variation torque gain GRout applied to the left rear wheel motor M_RL at the time of entering a corner at the start of right turning (t1-t2). For example, as shown in (C), (D) of FIG. 11, the variation torque deriving section 33 can set the variation torque gain GRout to a value larger than the variation torque gain GFout at the time of exiting a corner at the end of right turning (t3-t4).

[0050] The variation torque deriving section 33 can smoothly change the values of the variation torque gain GFout and the variation torque gain GRout in response to a change in load generated at each wheel T on the outer wheel side. The variation torque deriving section 33 can calculate the change in load, for example, on the basis of load data obtained by a load sensor. The variation torque deriving section 33 can calculate the change in load, for example, on the basis of data obtained by various sensors other than the load sensor.

[0051] For example, as shown in (A), (B) of FIG. 11, the variation torque deriving section 33 can set the variation torque gain GFout applied to the left front wheel motor M_FL to a value larger than the variation torque gain GRout applied to the left rear wheel motor M_RL at the time of entering a corner at the start of right turning (t1-t2). For example, as shown in (C), (D) of FIG. 11, the variation torque deriving section 33 can set the variation torque gain GRout to a value larger than the variation torque gain GFout at the time of exiting a corner at the end of right turning (t3-t4). Figure 5 ​​As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4). Figure 5 As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4). Figure 5 As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4).

[0052] As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4). Figure 6 As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4). Figure 6 As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4). Figure 6 As shown in (C) of FIG. 10, the variation torque deriving section 33 can smoothly change (increase) the value of the gain (variation torque gain GFout) of the right front wheel variation torque Tf FR in response to a change in the load generated at the right front wheel T FR at the time of entering the corner at the start of the left turn (tl ~ t2). For example, as shown in (A) of FIG. 11, the variation torque deriving section 33 can smoothly change (decrease) the value of the gain (variation torque gain GFout) of the left front wheel variation torque Tf FL in response to a change in the load generated at the left front wheel T FL at the time of exiting the corner at the end of the right turn (t3 ~ t4).

[0053] The variation torque deriving section 33 can set the gain of the variation torque Tf applied to each motor M to a value that is equal to or less than the variation torque gain Gout and equal to or more than the variation torque gain Gin when it is detected that the vehicle 1 is traveling straight. Specifically, the variation torque deriving section 33 can set the gain of the variation torque Tf applied to each motor M to a value that is smaller than the variation torque gain Gout applied to the outer front wheel motor M at the time of steady turning (t2 ~ t3) and larger than the variation torque gain Gin applied to the inner front wheel motor M at the time of steady turning (t2 ~ t3) when it is detected that the vehicle 1 is traveling straight.

[0054] The motor torque control section 34 can independently control the torques of the four motors (the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR). In the case where the travel mode is the normal mode, the motor torque control section 34 can set the requested torque Tr of each wheel T as the target torque Tg of each wheel T. The motor torque control section 34 can further control the torques of the four motors (the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR) on the basis of the set target torque Tg of each wheel T.

[0055] In the case where the travel mode becomes the torque variation control mode, the motor torque control section 34 can derive the target torque Tg of each wheel T by adding the variation torque Tf of each wheel T to the requested torque Tr of each wheel T (refer to Figure 4 C). The motor torque control section 34 can further control the torques of the four motors (the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR) on the basis of the derived target torque Tg of each wheel T.

[0056] The motor torque control section 34 can determine whether or not to add the variation torque Tf to the requested torque Tr on the basis of the control flag 22. The motor torque control section 34 can, for example, derive the target torque Tg by adding the variation torque Tf to the requested torque Tr in the case where the control flag 22 indicates the torque variation control mode. The motor torque control section 34 can, for example, set the requested torque Tr as the target torque Tg without adding the variation torque Tf to the requested torque Tr in the case where the control flag 22 indicates the normal mode.

[0057] The control flag input section 40 can receive the input of the control flag 22 from the driver. The control flag input section 40 is, for example, a shift key attached to a steering wheel. The control flag input section 40 can, for example, store "1" as the control flag 22 in the storage section 20 in the case where the driver simultaneously long-presses left and right shift keys. The control flag input section 40 can, for example, store "0" as the control flag 22 in the storage section 20 in the case where the driver again simultaneously long-presses the left and right shift keys after "1" has been stored as the control flag 22 in the storage section 20 the previous time. The control flag input section 40 can, for example, store "1" as the control flag 22 in the storage section 20 in the case where the driver again simultaneously long-presses the left and right shift keys after "0" has been stored as the control flag 22 in the storage section 20 the previous time.

[0058] In the case where the control flag 22 is "1", the control flag 22 indicates, for example, that the torque variation control mode is in progress. In the case where the control flag 22 is "0", the control flag 22 indicates, for example, that the normal mode in which the periodic torque variation control is not performed is in progress. Furthermore, the values adoptable as the control flag 22 are not limited to the above-described values.

[0059] [Operation]

[0060] Next, the operation of the travel control section 31 will be described with reference to Figure 7 , Figure 8 . Figure 7 , Figure 8 is a diagram showing one example of the derivation step of the target torque Tg.

[0061] The travel control section 31 acquires an acceleration request from the accelerator opening sensor 11 (step S101). Next, the travel control section 31 derives a request torque Tr in response to the acquired acceleration request (step S102). Next, the travel control section 31 sets the target torque Tg of all the wheels T to Tr when the control flag 22 input from the control flag input section 40 indicates the normal mode (step S103; No), (step S104).

[0062] The travel control section 31 sets the variation torque gain G of all the wheels T to G2 when the control flag 22 input from the control flag input section 40 indicates the variation torque control mode (step S103; Yes) (step S105). The travel control section 31 further sets the target torque Tg of all the wheels T to Tr + Tf (= Tr + G x Tf0) using the set variation torque gain G (step S106).

[0063] The travel control section 31 determines whether the vehicle 1 is straight traveling based on the value of at least one of the steering angle of the steering wheel, the acceleration in the front-rear and lateral directions, and the yaw rate (step S107). The travel control section 31 executes step S105 when it is determined that the vehicle 1 is straight traveling (step S107; Yes). The travel control section 31 determines whether the vehicle 1 is left turning when it is determined that the vehicle 1 is not straight traveling (step S107; No) (step S108).

[0064] The travel control section 31 determines whether it is at the time when the vehicle 1 starts left turning, that is, at the time when the corner is entered, when it is determined that the vehicle 1 is left turning (step S108; Yes) (step S109). The travel control section 31 raises the variation torque gain G of the right front wheel T FR to G3 when it is determined that it is at the time when the vehicle 1 starts left turning, that is, at the time when the corner is entered (step S109; Yes) (step S110). The travel control section 31 also reduces the variation torque gains G of the left front and rear wheels to Gl (step S111). The travel control section 31 determines whether it is at the time when the vehicle 1 exits the corner when it is determined that it is not at the time when the vehicle 1 starts left turning, that is, at the time when the corner is entered (step S109; No) (step S112).

[0065] The travel control portion 31 temporarily increases the variation torque gain G of the right rear wheel T_RR to G3 (step S113) in a case where it is determined that the vehicle 1 is turning out of the corner (step S112; YES). The travel control portion 31 also decreases the variation torque gain G of the right front wheel T_FR to G2 (step S114). The travel control portion 31 maintains the variation torque gain G of each wheel T in a case where it is determined that the vehicle 1 is not turning out of the corner, that is, in a case where the angular velocity of the vehicle 1 is constant (step S112; NO).

[0066] The travel control portion 31 determines whether or not the vehicle 1 is turning into the corner at the start of the right turn in a case where it is determined that the vehicle 1 is not turning left, that is, is turning right (step S108; NO) (step S115). The travel control portion 31 increases the variation torque gain G of the left front wheel T_FL to G3 (step S116) in a case where it is determined that the vehicle 1 is turning into the corner at the start of the right turn (step S115; YES). The travel control portion 31 also decreases the variation torque gain G of the right front and rear wheels to G1 (step S117). The travel control portion 31 determines whether or not the vehicle 1 is turning out of the corner in a case where it is determined that the vehicle 1 is not turning into the corner at the start of the right turn (step S115; NO) (step S118).

[0067] The travel control portion 31 increases the variation torque gain G of the left rear wheel T_RL to G3 (step S119) in a case where it is determined that the vehicle 1 is turning out of the corner (step S118; YES). The travel control portion 31 also decreases the variation torque gain G of the left front wheel T_FL to G2 (step S120). The travel control portion 31 maintains the variation torque gain G of each wheel T in a case where it is determined that the vehicle 1 is not turning out of the corner, that is, in a case where the angular velocity of the vehicle 1 becomes constant (step S118; NO).

[0068] As described above, the travel control portion 31 sets the variation torque gain G of the four motors M (the left front wheel motor M_FL, the right front wheel motor M_FR, the left rear wheel motor M_RL, and the right rear wheel motor M_RR). The travel control portion 31 sets the target torque Tg of each wheel T on the basis of the variation torque gain G of each wheel T set as shown in (A) to (D) in FIG. 6, for example, in the left turn, and performs torque control of each motor on the basis of the set target torque Tg of each wheel T. The travel control portion 31 sets the target torque Tg of each wheel T on the basis of the variation torque gain G of each wheel T set as shown in (A) to (D) in FIG. 7, for example, in the right turn, and performs torque control of each motor on the basis of the set target torque Tg of each wheel T. Figure 5 Figure 6 The travel control portion 31 sets the target torque Tg of each wheel T on the basis of the variation torque gain G of each wheel T set as shown in (A) to (D) in FIG. 7, for example, in the right turn, and performs torque control of each motor on the basis of the set target torque Tg of each wheel T.

[0069] [Effects]​

[0070] Next, the effects of the control unit 30 and the vehicle 1 according to the embodiment of the present disclosure will be described.

[0071] In the present embodiment, the target torque Tg of each wheel T is derived by adding the fluctuation torque Tf of the periodic fluctuation of each wheel T to the requested torque Tr of each wheel T in response to the accelerator opening degree, and the torque control is performed on each motor M based on the derived target torque Tg of each wheel T. At this time, in the case where it is detected that the vehicle 1 is turning, the gain of the fluctuation torque Tf applied to each motor M on the outer wheel side is set to a value larger than the gain of the fluctuation torque Tf applied to each motor M on the inner wheel side. Thereby, when the vehicle 1 is running on a curve, the motor M on the outer wheel, which is subjected to a larger load than the inner wheel, is applied with a target torque Tg having a larger vibration amplitude, and the motor M on the inner wheel, which is subjected to a smaller load than the outer wheel, is applied with a target torque Tg having a smaller vibration amplitude. As a result, in rainy weather or on a snowy road, an icy road, or the like, a low-μ road, the driver can be made to know early that the grip of the outer wheel is reduced, and the situation where the vehicle 1 rotates due to a slip or the situation where the vehicle 1 understeers can be prevented. As described above, in the present embodiment, the torque control corresponding to the curve running can be performed.

[0072] In addition, in the present embodiment, at the time of starting the turning, that is, at the time of entering a corner, the gain of the fluctuation torque Tf applied to the motor M of the front outer wheel is set to a value larger than the gain of the fluctuation torque Tf applied to the motor M of the rear outer wheel. Thereby, at the time when the vehicle 1 enters a corner, the motor M of the front outer wheel, which is subjected to a larger load than the rear outer wheel, is applied with a target torque Tg having a larger vibration amplitude, and the motor M of the rear outer wheel, which is subjected to a smaller load than the front outer wheel, is applied with a target torque Tg having a smaller vibration amplitude. Also, at the time of ending the turning, that is, at the time of exiting a corner, the gain of the fluctuation torque Tf applied to the motor M of the rear outer wheel is set to a value larger than the gain of the fluctuation torque Tf applied to the motor M of the front outer wheel. Thereby, at the time when the vehicle 1 exits a corner, the motor M of the rear outer wheel, which is subjected to a larger load than the front outer wheel, is applied with a target torque Tg having a larger vibration amplitude, and the motor M of the front outer wheel, which is subjected to a smaller load than the rear outer wheel, is applied with a target torque Tg having a smaller vibration amplitude.

[0073] As a result, in rainy weather or on a snowy road, an icy road, or the like, a low-μ road, the driver can be made to know early that the grip of the front outer wheel at the time of entering a corner and the grip of the rear outer wheel at the time of exiting a corner are reduced. Therefore, the situation where the vehicle 1 rotates due to a slip or the situation where the vehicle 1 understeers can be prevented. As described above, in the present embodiment, the torque control corresponding to the curve running can be performed.

[0074] In addition, in the present embodiment, the value of the gain of the variation torque Tf applied to the motor M of the outer wheel is smoothly changed in response to a change in the load generated by the outer wheel. Thereby, it is possible to make the driver aware of a decrease in the road surface frictional force of the front outer wheel when entering the corner and a decrease in the road surface frictional force of the rear outer wheel when exiting the corner early, while making the operation of the vehicle smooth. Thus, it is possible to prevent the vehicle 1 from rotating due to the occurrence of a slip or understeer of the vehicle 1. As described above, in the present embodiment, it is possible to perform the torque control corresponding to the cornering.

[0075] In addition, in the present embodiment, in a case where it is detected that the vehicle 1 is traveling straight, the variation torque gain G applied to each motor M is set to a value smaller than the variation torque gain G applied to the motor M of the outer wheel when the vehicle 1 is cornering and set to a value larger than the variation torque gain G applied to the motor M of the inner wheel when the vehicle 1 is cornering. Thereby, in rainy weather or in a low friction coefficient road (low μ road) such as a snowy road or an icy road, it is possible to make the driver aware of a decrease in the road surface frictional force of each wheel T when traveling straight early. Thus, it is possible to prevent the vehicle 1 from rotating due to the occurrence of a slip. As described above, in the present embodiment, it is possible to perform the torque control corresponding to the straight traveling.

[0076] In addition, in the present embodiment, it is possible to detect whether the vehicle 1 is turning based on the value of at least one of the steering angle of the steering wheel, the front-rear and lateral accelerations, and the yaw rate. Thereby, it is possible to perform the torque control corresponding to the cornering or the straight traveling.

[0077] <2. Modification>

[0078] The above describes the present disclosure based on the embodiment, but the present disclosure is not limited to the embodiment and various modifications can be made.

[0079] [Modification A]

[0080] Figure 9 is a diagram showing one modification of the functional blocks of the vehicle 1 of the above-described embodiment. In the present modification, for example, as shown in Figure 9 the sensor section 10 can further have a road surface state amount sensor 13 and the travel control section 31 can further have a road surface μ estimation section 35.

[0081] The road surface state amount sensor 13 can detect information indicating the state of the road surface of the lane on which the vehicle 1 is traveling, i.e., a road surface state amount. The road surface state amount sensor 13 can output time-series data of the detected road surface state amount (road surface state amount data) to the control unit 30. The road surface state amount sensor 13 includes, for example, a camera, a temperature sensor (an outside air temperature sensor, a road surface temperature sensor), a near-infrared sensor, and a laser sensor (a TOF (Time Of Flight) sensor) as a sensor that can detect a road surface state amount.

[0082] The camera can acquire an image of the front of the vehicle 1. The camera can output time-series data of the acquired image (image data) to the control unit 30. The outside air temperature sensor can detect the temperature around the vehicle 1. The outside air temperature sensor can output time-series data of the detected temperature (outside air temperature data) to the control unit 30. The road surface temperature sensor can detect the temperature of the road surface of the lane on which the vehicle 1 travels. The road surface temperature sensor can output time-series data of the detected temperature (road surface temperature data) to the control unit 30.

[0083] The near-infrared sensor can irradiate near-infrared rays to the road surface of the lane on which the vehicle 1 travels, and detect reflected light of the near-infrared region from the road surface. The near-infrared sensor can output time-series data of the detected reflected light of the near-infrared region (near-infrared data) to the control unit 30. The laser sensor can irradiate laser light to the road surface of the lane on which the vehicle 1 travels, and detect reflected light of the laser light from the road surface. The laser sensor can output time-series data of the detected reflected light of the laser light (laser data) to the control unit 30.

[0084] The road surface μ estimation section 35 can estimate the road surface μ value on the basis of the road surface state quantity data input from the road surface state quantity sensor 13. The road surface μ estimation section 35 can estimate, for example, the color, the road surface roughness, and the like of the road surface in front of the vehicle 1 from the image data of the camera. The road surface μ estimation section 35 can estimate, for example, the amount of moisture of the road surface on which the vehicle 1 travels on the basis of the outside air temperature data, the road surface temperature data, and the near-infrared data. The road surface μ estimation section 35 can estimate, for example, the state (for example, dry, wet) or the kind (for example, asphalt, snow, ice) of the road surface on which the vehicle 1 travels on the basis of the laser data. The road surface μ estimation section 35 can estimate, for example, the coefficient of friction (road surface μ value) of the road surface on which the vehicle 1 travels on the basis of the data (for example, at least one of the color, the road surface roughness, the amount of moisture, the state, and the kind of the road surface) estimated thereby. Furthermore, the road surface μ estimation section 35 can estimate the road surface μ value by a method other than the above.

[0085] The road surface μ estimation section 35 can also calculate, for example, the slip rate s of each wheel T using the following formula. In the following formula, V is the speed of the vehicle 1, and Vw is the speed of the wheel T. The road surface μ estimation section 35 can output the road surface μ value estimated thereby and the slip rate s calculated thereby to the motor torque control section 34.

[0086] s = (V - Vw) / Vw

[0087] As Figure 10As shown, the motor torque control section 34 can detect a low-μ region a included in the road surface ahead of the vehicle 1 and a high-μ region β included in the road surface ahead of the vehicle 1 based on the road surface μ value obtained by the road surface μ estimation section 35, for example. The low-μ region a is a region in which the road surface μ value is smaller than the road surface μ value of the surrounding road surface. The motor torque control section 34 can set the gain of the fluctuation torque Tf applied to the motor M corresponding to the wheel T passing through the low-μ region a to a value larger than the gain of the fluctuation torque Tf applied to the motor M corresponding to the wheel T not passing through the low-μ region a in a case where the low-μ region a is detected.

[0088] Next, the operation of the vehicle 1 according to the present embodiment will be described with reference to the flowchart shown in FIG. 6. Figure 11 The operation of the travel control section 31 will be described. Figure 11 FIG. 7 is a diagram showing one example of a derivation step of the fluctuation torque gain G.

[0089] The travel control section 31 acquires road surface state quantity data from the road surface state quantity sensor 13 (step S201). The travel control section 31 estimates the road surface μ value based on the acquired road surface state quantity data (step S202). The travel control section 31 also calculates the slip rate s of each wheel T using s = (V - Vw) / Vw (step S203).

[0090] The travel control section 31 detects the low-μ region a included in the road surface ahead of the vehicle 1 and the high-μ region β included in the road surface ahead of the vehicle 1 based on the road surface μ value. The travel control section 31 determines whether there is a wheel T passing through the low-μ region a among the motors M in a case where the low-μ region a is detected (step S204). The travel control section 31 increases the gain of the fluctuation torque Tf applied to the motor M corresponding to the wheel T passing through the low-μ region a by ΔG1 in a case where there is a wheel T passing through the low-μ region a among the motors M (step S204; YES) (step S205).

[0091] The travel control section 31 determines whether there is a wheel T slipping based on the slip rate s of each wheel T (step S206). The travel control section 31 increases the gain of the fluctuation torque Tf applied to the motor M corresponding to the wheel T slipping by ΔG2 in a case where there is a wheel T slipping (step S206; YES) (step S207). In this way, the fluctuation torque gain G taking into account the low-μ region a is obtained.

[0092] Next, the effect of the vehicle 1 according to the present embodiment will be described.

[0093] In the present modification example, in the case where the low μ region α is detected, the gain of the fluctuation torque Tf applied to the motor M corresponding to the wheel T passing through the low μ region α is set to a value larger than the gain of the fluctuation torque Tf applied to the motor M corresponding to the wheel T not passing through the low μ region α. Thus, in rainy weather or in a low friction coefficient road (low μ road) such as a snowy road or an icy road, the driver can be made to know in advance that the vehicle 1 passes through the low μ region α, so it is possible to prevent the vehicle 1 from rotating due to a slip or a situation where the vehicle 1 understeers. As described above, in the present modification example, torque control corresponding to low μ road travel can be performed.

[0094] The effects described in this specification are merely illustrative and the effects of the present disclosure are not limited to the effects described in this specification. Thus, with respect to the present disclosure, other effects can also be obtained.

[0095] Furthermore, the present disclosure can adopt the following modes.

[0096] (1) A vehicle control device capable of controlling a vehicle having four wheels and four motors each provided for each of the wheels, the vehicle being capable of traveling by independently driving each of the motors, wherein

[0097] the vehicle control device has a control unit that derives a target torque of each of the wheels by adding a fluctuation torque of each of the wheels that fluctuates periodically to a requested torque of each of the wheels that responds to an accelerator opening degree, and performs torque control of each of the motors based on the derived target torque of each of the wheels,

[0098] the control unit is capable of setting a first gain of the fluctuation torque applied to each of the motors on an outer wheel side to a value larger than a second gain of the fluctuation torque applied to each of the motors on an inner wheel side in the case where the vehicle is detected to be turning.

[0099] (2) The vehicle control device according to (1), wherein

[0100] the control unit is capable of performing steps of:

[0101] setting a third gain of the fluctuation torque applied to a motor on a front wheel side among each of the motors on the outer wheel side to a value larger than a fourth gain of the fluctuation torque applied to a motor on a rear wheel side among each of the motors on the outer wheel side at the time of starting the turning, that is, at the time of entering a corner; and

[0102] setting the fourth gain to a value larger than the third gain at the time of ending the turning, that is, at the time of exiting the corner.

[0103] (3) The vehicle control device according to (2), wherein

[0104] The control unit is able to respond to changes in load generated by each of the wheels on the outer wheel side, causing the values ​​of the third gain and the fourth gain to change smoothly.

[0105] (4) The vehicle control device according to any one of (1) to (3), wherein,

[0106] The control unit is able to set the gain of the variable torque applied to each of the motors to a value that is smaller than the first gain and larger than the second gain when the vehicle is detected to be traveling straight.

[0107] (5) The vehicle control device according to any one of (1) to (4), wherein,

[0108] When the control unit detects a low friction coefficient region where the road surface friction coefficient is smaller than that of the surrounding road surface, it sets the gain of the variable torque applied to the motor corresponding to the wheel passing through the low friction coefficient region to a value greater than the gain of the variable torque applied to the motor corresponding to the wheel not passing through the low friction coefficient region.

[0109] In a vehicle control device according to one embodiment of this disclosure, a target torque for each wheel is derived by adding the periodically varying torque of each wheel to the requested torque of each wheel in response to the throttle opening. Torque control is then performed on each motor based on the derived target torque for each wheel. When a vehicle turning is detected, the gain of the varying torque applied to the motors on the outer wheel side is set to a value greater than the gain of the varying torque applied to the motors on the inner wheel side. Therefore, when the vehicle is traveling in a curve, a target torque with a large vibration amplitude is applied to the motors on the outer wheels, which experience a greater load than the inner wheels, and a target torque with a small vibration amplitude is applied to the motors on the inner wheels, which experience a smaller load than the outer wheels. As a result, in rainy weather or on low-friction roads (low μ roads) such as snow or ice, the driver can be aware of the reduced grip of the outer wheels in advance, thus preventing vehicle spin due to slippage or understeer. In summary, this disclosure enables torque control corresponding to cornering.

[0110] like Figure 1 , Figure 8 The control unit 30 shown can be implemented by a circuit including at least one semiconductor integrated circuit, such as at least one processor (e.g., a central processing unit (CPU)), at least one application-specific integrated circuit (ASIC), and / or at least one field-programmable gate array (FPGA). The at least one processor is configured to execute instructions by reading from at least one non-transitory and tangible computer-readable medium.Figure 1 、 Figure 8 All or a part of the various functions of the control unit 30 shown in FIG. 1 can be implemented by a medium. Such a medium can take various forms including various magnetic media such as a hard disk, various optical media such as a CD (Compact disc) or a DVD (Digital Video Disk), various semiconductor memories (i.e., semiconductor circuits) such as a volatile memory or a non-volatile memory, but is not limited to these. The volatile memory can include a DRAM (Dynamic Random Access Memory) and an SRAM (Static Random Access Memory). The non-volatile memory can include a ROM (Read Only Memory) and an NVRAM (Non-volatile Random Access Memory). The ASIC is an integrated circuit (IC) that is exclusively used to execute all or a part of the various functions of the control unit 30 shown in FIG. 1. The FPGA is an integrated circuit that is designed to be configurable to execute all or a part of the various functions of the control unit 30 shown in FIG. 1 after manufacture. Figure 1 、 Figure 8 All or a part of the various functions of the control unit 30 shown in FIG. 1 can be implemented by a medium. Such a medium can take various forms including various magnetic media such as a hard disk, various optical media such as a CD (Compact disc) or a DVD (Digital Video Disk), various semiconductor memories (i.e., semiconductor circuits) such as a volatile memory or a non-volatile memory, but is not limited to these. The volatile memory can include a DRAM (Dynamic Random Access Memory) and an SRAM (Static Random Access Memory). The non-volatile memory can include a ROM (Read Only Memory) and an NVRAM (Non-volatile Random Access Memory). The ASIC is an integrated circuit (IC) that is exclusively used to execute all or a part of the various functions of the control unit 30 shown in FIG. 1. The FPGA is an integrated circuit that is designed to be configurable to execute all or a part of the various functions of the control unit 30 shown in FIG. 1 after manufacture. Figure 1 、 Figure 8 All or a part of the various functions of the control unit 30 shown in FIG. 1 can be implemented by a medium. Such a medium can take various forms including various magnetic media such as a hard disk, various optical media such as a CD (Compact disc) or a DVD (Digital Video Disk), various semiconductor memories (i.e., semiconductor circuits) such as a volatile memory or a non-volatile memory, but is not limited to these. The volatile memory

Claims

1. A vehicle control device capable of controlling a vehicle having four wheels and four motors each provided to each of the wheels, the vehicle being able to travel by independently driving each of the motors, wherein the vehicle control device has a control unit that derives a target torque of each of the wheels by adding a fluctuation torque of each of the wheels that fluctuates periodically to a requested torque of each of the wheels that fluctuates in response to an accelerator opening degree, and performs torque control of each of the motors based on the derived target torque of each of the wheels, the control unit is able to set a first gain of the fluctuation torque applied to each of the motors on an outer wheel side to a value larger than a second gain of the fluctuation torque applied to each of the motors on an inner wheel side, in a case where the vehicle is detected to be turning.

2. The vehicle control device according to claim 1, wherein the control unit is able to perform steps of: setting a third gain of the fluctuation torque applied to a motor on a front wheel side among each of the motors on the outer wheel side to a value larger than a fourth gain of the fluctuation torque applied to a motor on a rear wheel side among each of the motors on the outer wheel side, at a time of entering a corner when the turning is started; and setting the fourth gain to a value larger than the third gain, at a time of exiting the corner when the turning is ended.

3. The vehicle control device according to claim 2, wherein the control unit is able to smoothly change values of the third gain and the fourth gain in response to a change in load generated at each of the wheels on the outer wheel side.

4. The vehicle control device according to claim 1, wherein the control unit is able to set a gain of the fluctuation torque applied to each of the motors to a value smaller than the first gain and larger than the second gain, in a case where the vehicle is detected to be traveling straight.

5. The vehicle control device according to any one of claims 1 to 4, wherein the control unit is able to set a gain of the fluctuation torque applied to the motor corresponding to a wheel that passes through a low friction coefficient region where a road surface friction coefficient value is smaller than a road surface friction coefficient value of a surrounding road surface, to a value larger than a gain of the fluctuation torque applied to the motor corresponding to a wheel that does not pass through the low friction coefficient region, in a case where the low friction coefficient region is detected. ​ ​ ​ ​ ​ ​ ​ ​ ​

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