JP6865657B2 - Vehicle control device and vehicle control method - Google Patents

Description

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

Conventionally, there is known a vehicle in which each of the left and right wheels is provided with an in-wheel motor and each wheel is independently rotationally driven. In such a vehicle, since the left and right wheels are not connected by a hardware mechanism such as a drive shaft, a torque command value is output to each of the motors of the left and right wheels to drive the motors (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2010-247804

Here, for example, due to differences in the output characteristics of the motors on the left and right wheels, the actual torque value may differ for each motor even if the torque command value is the same (that is, during straight-ahead control). Therefore, in the conventional technique, there is a possibility that the straightness of the vehicle may be deteriorated because the actual traveling direction at the time of straight-ahead control deviates from the straight-ahead direction. Similarly, during turning control, the assumed turning radius and the actual turning radius in control are different from each other due to the influence of the difference in the actual torque value, and there is a possibility that the turning performance may be deteriorated.

The present invention has been made in view of the above, and an object of the present invention is to provide a vehicle control device and a vehicle control method capable of preventing a decrease in the traveling performance of a vehicle.

In order to solve the above-mentioned problems and achieve the object, the vehicle control device according to the present invention includes a detection unit and a lean control unit. The detection unit detects the difference between the actual traveling direction of the vehicle having the lean actuator that tilts the vehicle body in the vehicle width direction and the reference direction predetermined according to the steering input. The lean control unit controls the lean actuator based on the difference detected by the detection unit.

According to the present invention, it is possible to prevent the traveling performance of the vehicle from deteriorating.

FIG. 1A is a diagram showing an outline of a vehicle control method according to an embodiment. FIG. 1B is a diagram showing an outline of a vehicle control method according to an embodiment. FIG. 2 is a block diagram showing a configuration of a vehicle control system according to an embodiment. FIG. 3 is a block diagram showing a configuration of a vehicle control device according to an embodiment. FIG. 4 is a diagram showing the processing contents of the lean control unit. FIG. 5 is a diagram showing the processing contents of the lean control unit. FIG. 6 is a flowchart showing a processing procedure of processing executed by the vehicle control device according to the embodiment.

Hereinafter, embodiments of the vehicle control device and the vehicle control method disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

1A and 1B are diagrams showing an outline of a vehicle control method according to an embodiment. The vehicle C shown in FIG. 1A is a single-seater three-wheeled vehicle having two front wheel FWs arranged on the left and right sides of the vehicle body and one rear wheel RW arranged in the center of the vehicle body in the vehicle width direction in the Y-axis direction. Type mobility.

The vehicle C may be, for example, a four-wheel type vehicle having one front wheel FW and two rear wheel RWs, or two front wheel FWs and two rear wheel RWs. ..

Further, the vehicle C has a lean actuator that tilts the vehicle body in the Y-axis direction, which is the vehicle width direction. For example, the vehicle C drives the lean actuator to tilt the vehicle body when turning. Further, the vehicle C has an in-wheel motor (hereinafter, IWM) for each of the two front wheel FWs, and since the two front wheel FWs are not connected by a hard mechanism such as a drive shaft, each IWM is independent. The vehicle C is accelerated / decelerated by driving the vehicle C.

Further, regarding the steering control, the vehicle C employs a so-called steer-by-wire system which does not have a mechanical link mechanism and electrically controls the steering based on the steering input of the steering angle sensor.

Further, FIG. 1B shows a top view of the vehicle C, and shows a case where the steering input is in the straight-ahead direction 101. Here, in the case of the vehicle C in which the two front wheel FWs as described above are driven independently, an output difference may occur between the left and right front wheel FWs. Factors that cause such an output difference include a difference due to the hardware characteristics of the IWM, a voltage difference of a battery that supplies power to each IWM, and the like.

When an output difference occurs between the left and right front wheel FWs in this way, a difference occurs between the actual traveling direction 100 and the straight traveling direction 101 of the vehicle C. Therefore, regardless of the straight-ahead control, the vehicle C does not move in the straight-ahead direction 101, which may reduce the straightness.

Further, the turning performance of the vehicle C may be deteriorated by being affected by such a difference not only in the straight direction 101 but also in turning. That is, the traveling performance of the vehicle C may deteriorate.

Therefore, the vehicle control device 1 according to the embodiment detects a difference between the actual traveling direction 100 and the reference direction (for example, the straight traveling direction 101), and controls the lean actuator based on the difference. The reference direction refers to a predetermined traveling direction of the vehicle C according to the steering input of the steering angle sensor or the like.

For example, in the situation shown in FIG. 1B, in the vehicle control method according to the embodiment, the vehicle body is tilted toward the Y-axis positive direction side opposite to the actual traveling direction 100 with respect to the straight traveling direction 101, so that the vehicle traveling direction 101 is obtained. The difference from the actual traveling direction 100 is canceled. As a result, it is possible to prevent the straightness from being lowered. It is preferable that the angle at which the vehicle body is tilted is within a range that does not cause discomfort to the driver.

As described above, according to the vehicle control method according to the embodiment, when there is a difference between the actual traveling direction 100 and the reference direction, the difference can be reduced by controlling the lean actuator and tilting the vehicle body. Therefore, the vehicle C It is possible to prevent the running performance of the vehicle from deteriorating.

Next, the vehicle control system S including the vehicle control device 1 according to the embodiment will be described. FIG. 2 is a block diagram showing a configuration of the vehicle control system S according to the embodiment. Note that, in FIG. 2, only the components necessary for explaining the features of the present embodiment are represented by functional blocks, and the description of general components is omitted.

The vehicle control system S includes two control systems duplicated by the systems A and B. Further, the vehicle control system S includes a power supply ECU 50 that controls the power supplies of both systems A and B.

The system A includes an integrated ECU 1a, a lean ECU 2a, a steering ECU 3a, a battery ECU 4a, and an IWMEME 5a. The integrated ECU 1a corresponds to the vehicle control device 1 in FIG. 1B.

The integrated ECU 1a controls the entire system A. The integrated ECU 1a is a higher-level ECU, and the lean ECU 2a, the steer ECU 3a, the battery ECU 4a, and the IWME ECU 5a are lower-level ECUs.

The integrated ECU 1a is connected to each ECU so as to be able to communicate with each other through an in-vehicle network such as CAN (Controller Area Network). The integrated ECU 1a is connected to the lean ECU 2b, the steering ECU 3b, the battery ECU 4b, and the IWME ECU 5b of the system B so as to be intercommunication through CAN or the like.

Further, the lean ECU 2a, the steer ECU 3a, the battery ECU 4a, and the IWME ECU 5a are connected to the integrated ECU 1b of the system B so as to be able to communicate with each other through CAN or the like. The detailed functional blocks of the integrated ECU 1a will be described later.

The battery ECU 4a monitors the deterioration of the battery 14a. By controlling the lean actuator (lean ACT) 12a, the lean ECU 2a tilts the vehicle body in the left-right direction, which is the vehicle width direction, in response to the turning acceleration in order to facilitate the turning of the vehicle C (see FIG. 1A). At the same time, the tilted state of the vehicle body in the left-right direction is appropriately maintained so that the vehicle C does not fall.

The steering ECU 3a controls the steering actuator (steering ACT) 13a so that the vehicle C travels in response to the driver's steering operation.

The IWMECU 5a controls an in-wheel motor (IWM) 15a provided on the left front wheel FW of the vehicle C so that the vehicle C is accelerated or braked in response to the driver's accelerator operation or brake operation.

The lean ACT 12a tilts the vehicle body in the left-right direction based on an instruction from the lean ECU 2a, that is, an instruction signal, and changes the posture of the vehicle body when the vehicle C turns, for example. Further, the lean ACT12a changes the posture of the vehicle body according to the unevenness of the traveling road surface and the inclination. The steering ACT 13a changes the steering angle of the rear wheel RW based on an instruction (instruction signal) from the steering ECU 3a.

The IWM15a rotates the left front wheel FW based on an instruction (instruction signal) from the IWMECU 5a, and controls the rotation speed of the left front wheel FW. The battery 14a is a storage battery, for example, a lithium ion battery.

Similar to the system A, the system B includes an integrated ECU 1b, a lean ECU 2b, a steering ECU 3b, a battery ECU 4b, and an IWME ECU 5b. The integrated ECU 1b corresponds to the vehicle control device 1 in FIG. 1B.

Since each configuration of the system B has the same configuration as each configuration of the system A, the description here will be omitted. The IWMECU 5b controls an in-wheel motor (IWM) 15b provided on the right front wheel FW of the vehicle C so that the vehicle C is accelerated or braked in response to the driver's accelerator operation or brake operation.

Further, since the configurations of the lean ACT 12b, the steer ACT 13b, and the battery 14b controlled by the system B are the same as the configurations of the lean ACT 12a, the steer ACT 13a, and the battery 14a controlled by the system A, the description thereof is omitted here. To do. The IWM15b rotates the right front wheel FW based on an instruction (instruction signal) from the IWMECU 5b, and controls the rotation speed of the right front wheel FW.

Further, the vehicle control system S is duplicated in the system A and the system B as described above based on the fault tolerant design, for example, and the electronic control of the vehicle C is controlled by 50% each based on the fault tolerant design, for example. Can be shared with.

Specifically, for example, the lean ECUs 2a and 2b are responsible for 50% of the outputs of the respective lean ACTs 12a and 12b, and control the lean ACTs 12a and 12b so that the outputs of both systems A and B are 100%.

Further, for example, even if an abnormality occurs in one of the integrated ECUs 1a and 1b, the vehicle C can be moved to a safe place under the control of the other integrated ECUs 1a and 1b, for example.

In the following, when the systems A and B are not distinguished, the reference numerals “a” and “b” will be omitted. For example, the integrated ECU 1a and the integrated ECU 1b will be collectively referred to as an integrated ECU 1, and the lean ACT 12a and the lean ACT 12b will be collectively referred to as a lean ACT 12.

Next, the vehicle control device 1 corresponding to the integrated ECU 1 will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the vehicle control device 1 according to the embodiment. As shown in FIG. 3, the vehicle control device 1 according to the embodiment includes a camera 40, a right torque sensor 41, a left torque sensor 42, and a steering angle sensor 43.

The camera 40 is an in-vehicle camera and is provided at a position where the surroundings of the vehicle C are imaged. The camera 40 outputs an captured image of the surroundings of the vehicle C to the vehicle control device 1.

The right torque sensor 41 is a sensor that detects the actual torque (output value) of the front wheel FW on the right side of the vehicle C. The left torque sensor 42 is a sensor that detects the actual torque of the front wheel FW on the left side of the vehicle C. The right torque sensor 41 and the left torque sensor 42 output an output value, which is the detected actual torque, to the vehicle control device 1. The steering angle sensor 43 detects the steering angle associated with the steering operation of the vehicle C and outputs the steering angle to the vehicle control device 1.

Next, the vehicle control device 1 according to the embodiment will be described. The vehicle control device 1 includes a control unit 20 and a storage unit 30. The control unit 20 includes a detection unit 21 and a lean control unit 22. The storage unit 30 stores the neutral point information 31.

Here, the vehicle control device 1 is, for example, a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), an input / output port, and various circuits. including.

The CPU of the computer functions as the detection unit 21 and the lean control unit 22 of the control unit 20 by reading and executing the program stored in the ROM, for example.

Further, at least one or all of the detection unit 21 and the lean control unit 22 of the control unit 20 may be configured by hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

Further, the storage unit 30 corresponds to, for example, a RAM or an HDD. The RAM or HDD can store neutral point information 31, information on various programs, and the like. The vehicle control device 1 may acquire the above-mentioned program and various information via another computer or a portable recording medium connected by a wired or wireless network.

The neutral point information 31 is information about the neutral point of the lean ACT 12. When there is a difference between the actual traveling direction 100 and the reference direction, the lean control unit 22, which will be described later, adjusts the neutral point and updates the adjusted neutral point as new neutral point information 31. The update of the neutral point information 31 will be described later with reference to FIG.

The control unit 20 of the vehicle control device 1 detects a difference between the actual traveling direction 100 of the vehicle C and the reference direction, and controls the lean ACT 12 based on the difference.

The detection unit 21 detects the difference between the actual traveling direction 100 of the vehicle C and the predetermined reference direction according to the steering input. For example, the detection unit 21 derives the reference direction based on the steering angle information input from the steering angle sensor 43.

Specifically, when the steering angle is substantially zero and the torque command values to the left and right IWM15s are substantially the same (that is, during straight-ahead control), the detection unit 21 derives the straight-ahead direction 101 as a reference direction. Further, when the steering angle is not substantially zero (that is, during turning control), the detection unit 21 detects the turning direction of the turning radius according to the steering angle as the reference direction.

Further, the detection unit 21 detects the actual traveling direction 100 based on the output values input from the right torque sensor 41 and the left torque sensor 42. For example, during straight-ahead control, when the output value of the right torque sensor 41 is larger than the output value of the left torque sensor 42, the detection unit 21 detects the actual traveling direction 100 in the direction of turning to the left with respect to the straight-ahead direction 101. To do.

Further, the detection unit 21 calculates the turning radius of the actual traveling direction 100 according to the difference between the output values of both torque sensors, and detects the turning radius as the difference between the actual traveling direction 100 and the straight traveling direction 101.

That is, the detection unit 21 detects the output difference between the left and right wheels as a difference. By detecting the actual output difference between the left and right wheels in this way, the difference between the actual traveling direction 100 and the reference direction can be accurately detected.

The detection unit 21 is not limited to the case where the actual traveling direction 100 is detected based on the torque sensor, and may detect the actual traveling direction 100 by, for example, optical flow analysis of the captured image of the camera 40. Alternatively, the detection unit 21 may detect the actual traveling direction 100 by detecting the resolver angle of each of the IWM15s.

The lean control unit 22 outputs a control signal for controlling the lean ACT 12 to the lean ECU 2 based on the difference detected by the detection unit 21. Here, the processing contents of the lean control unit 22 will be specifically described with reference to FIGS. 4 and 5.

4 and 5 are diagrams showing the processing contents of the lean control unit 22. FIG. 4 shows a front view of the vehicle C, and FIG. 5 shows a top view of the vehicle C. Further, in FIGS. 4 and 5, for example, it is assumed that the output of the front wheel FW on the right side is larger than that of the front wheel FW on the left side by the output difference D during straight-ahead control.

In such a case, since a turning force to the left, which has a small output, acts on the vehicle C, the actual traveling direction 100 faces to the left with respect to the straight-ahead direction 101, as shown in FIG. Further, FIG. 4 shows a neutral axis O corresponding to the above-mentioned neutral point.

As shown in FIG. 4, when the front wheel FW on the left side has a larger output than the front wheel FW on the right side, the lean control unit 22 controls the lean ACT 12 so that the vehicle C tilts toward the high output side.

Specifically, the lean control unit 22 rotates and controls the drive motor 121 of the lean ACT 12 based on the detected difference (output difference D) to rotate the left and right front wheel FWs in the vertical Z-axis direction. Make it work.

In the example shown in FIG. 4, the lean control unit 22 rotates the drive motor 121 clockwise (arrow 300 in the figure) in the front view. As a result, the front wheel FW on the left side moves upward with the rotation operation, while the front wheel FW on the right side moves downward.

As a result, the vehicle C is tilted toward the front wheel FW side on the left side, which is the high output side (arrow 310 in the figure). In other words, the lean control unit 22 controls the lean ACT 12, so that the neutral axis O is tilted toward the high output side by an angle θ.

That is, the lean control unit 22 controls the lean ACT 12 so as to tilt the vehicle C to the side opposite to the actual traveling direction 100 with respect to the reference direction (for example, the straight-ahead direction 101). As a result, a turning force to the left side, which is the high output side, acts on the vehicle C, so that the actual traveling direction 100 can be returned to the reference direction side, and the difference between the reference direction and the actual traveling direction 100 can be reduced. Can be done.

Then, the lean control unit 22 sets the neutral axis O tilted by the angle θ as a new neutral axis O, and updates the neutral point information 31. That is, the lean control unit 22 adjusts the neutral point of the lean ACT 12 so that the detected difference becomes small.

By adjusting the neutral point in this way, the state in which the vehicle body is tilted by the angle θ is set as the default position. Therefore, after that, it is not necessary to perform the above lean control, and the processing load can be reduced. The angle θ is preferably in a range that does not give a sense of discomfort to the driver (for example, within 0.5 deg).

Further, as shown in FIG. 5, it is preferable that the lean control unit 22 controls the lean ACT 12 so as to cancel such a difference. Specifically, the lean control unit 22 controls the lean ACT 12 so that the actual traveling direction 100 overlaps with the straight traveling direction 101.

That is, the actual traveling direction 100 and the straight traveling direction 101 are made to coincide with each other. In this way, by matching the reference direction, which is the direction corresponding to the steering operation of the driver, with the actual traveling direction 100 of the vehicle C, it is possible to eliminate the driver's discomfort due to the steering operation.

The detection unit 21 detects that an abnormality has occurred in the IWM 15 when the detected output difference D is relatively large and the angle θ due to lean control is large enough to give the driver a sense of discomfort. In such a case, the lean control unit 22 performs an abnormality response process such as stopping both the IWM15s provided on the left and right front wheel FWs.

Next, the processing procedure of the processing executed by the vehicle control device 1 according to the embodiment will be described with reference to FIG. FIG. 6 is a flowchart showing a processing procedure of processing executed by the vehicle control device 1 according to the embodiment.

As shown in FIG. 6, first, the detection unit 21 detects the output values of the left and right wheels, that is, the left and right front wheel FWs, based on the detection values of the right torque sensor 41 and the left torque sensor 42, for example (step S101). ..

Subsequently, the detection unit 21 determines whether or not there is an output difference D, which is a difference between the output values of the left and right wheels (step S102). When the detection unit 21 determines that there is an output difference D (step S102, Yes), the detection unit 21 determines whether or not the output difference D is less than a predetermined value (step S103).

When the detection unit 21 determines that the output difference D is less than a predetermined value (step S103, Yes), the lean control unit 22 controls the lean ACT 12 to tilt the vehicle C toward the high output side (step). S104), the process is terminated.

On the other hand, in step S102, when the detection unit 21 determines that there is no output difference D (steps S102, No), the process ends. Further, in step S103, when the detection unit 21 determines that the output difference D is equal to or greater than a predetermined value (steps S103, No), it detects that an abnormality has occurred in the IWM15 (step S105).

Subsequently, when an abnormality of the IWM15 is detected, the lean control unit 22 performs a response process at the time of an abnormality such as stopping the IWM15 provided on the left and right front wheel FWs (step S106), and ends the process. ..

As described above, the vehicle control device 1 according to the embodiment includes a detection unit 21 and a lean control unit 22. The detection unit 21 detects the difference between the actual traveling direction 100 of the vehicle C having the lean actuator 12 that tilts the vehicle body in the vehicle width direction and the reference direction (for example, the straight traveling direction 101) predetermined according to the steering input. .. The lean control unit 22 controls the lean actuator 12 based on the difference detected by the detection unit 21. Thereby, for example, by controlling the lean actuator 12 to reduce such a difference, it is possible to prevent the traveling performance of the vehicle C from being deteriorated.

In the above-described embodiment, the case where the vehicle C is in straight-ahead control, that is, the case where the reference direction is the straight-ahead direction 101 has been described, but the vehicle C may be in turn control.

Specifically, the detection unit 21 detects the turning radius according to the steering angle as the reference direction during the turning control of the vehicle C, and detects the actual turning radius as the actual traveling direction 100. Then, the detection unit 21 detects the turning difference between the turning radius in the reference direction and the actual turning radius. The actual turning radius can be calculated from an image captured by the camera 40 by an analysis method such as an optical flow.

Then, the lean control unit 22 controls the lean ACT 12 based on the turning difference. For example, the lean control unit 22 controls the lean ACT 12 so that the actual turning radius is the same as the turning radius in the reference direction. As a result, it is possible to prevent the traveling performance of the vehicle C from deteriorating when traveling on a curve.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1,1a, 1b Vehicle control device (integrated ECU)
2,2a, 2b lean ECU
3,3a, 3b steer ECU
4,4a, 4b Battery ECU
5,5a, 5b IWMCU
12, 12a, 12b Lean ACT
13, 13a, 13b Steer ACT
14,14a, 14b Battery 15,15a, 15b IWM
20 Control unit 21 Detection unit 22 Lean control unit 30 Storage unit 31 Neutral point information 40 Camera 41 Right torque sensor 42 Left torque sensor 43 Steering angle sensor 50 Power supply ECU
C vehicle FW front wheel RW rear wheel

Claims (6)

The in-wheel motor provided in right and left wheels, a vehicle driving independently, is predetermined in accordance with the actual direction of travel and steering input of the vehicle having a lean actuator that tilts the vehicle body in the vehicle width direction A detector that detects the difference from the reference direction
A vehicle control device including a lean control unit that controls the lean actuator based on the difference detected by the detection unit. The detection unit
Detecting the difference during straight-ahead control of the vehicle,
The lean control unit
The first aspect of claim 1, wherein when the difference is detected by the detection unit, the lean actuator is controlled so as to tilt the vehicle toward the side opposite to the actual traveling direction with respect to the reference direction. Vehicle control device. The lean control unit
The vehicle control device according to claim 1 or 2, wherein the lean actuator is controlled so as to cancel the difference detected by the detection unit. The lean control unit
The vehicle control device according to any one of claims 1 to 3, wherein the neutral point of the lean actuator is adjusted so that the difference detected by the detection unit becomes small. Before Symbol detection unit,
The vehicle control device according to any one of claims 1 to 4, wherein a difference between the actual traveling direction and the straight traveling direction based on the output difference between the left and right wheels is detected as the difference. The in-wheel motor provided in right and left wheels, a vehicle driving independently, is predetermined in accordance with the actual direction of travel and steering input of the vehicle having a lean actuator that tilts the vehicle body in the vehicle width direction A detection process that detects the difference from the reference direction,
A vehicle control method comprising a lean control step of controlling the lean actuator based on the difference detected by the detection step.

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