WO2020138494A1 - Vehicle - Google Patents

Abstract

This vehicle comprises a body, N (an integer of three or more) number of vehicle wheels including at least one turning wheel capable of turning in the width direction of the body and including left and right drive wheels, a drive system, a steering drive device, an inclination device, an inclination drive device, a vehicle speed sensor, a vehicle wheel angle sensor, an operation input unit, and a control device. When a condition is met which includes the vehicle speed being less than a first threshold and the state of the steering drive device being a problematic state, the control device controls the difference between a left torque, which is the torque of the left drive wheel applied by the drive system, and a right torque, which is the torque of the right drive wheel, so that the vehicle wheel angle approaches a target vehicle wheel angle.

Description

vehicle

The present description relates to a vehicle that turns while tilting the vehicle body.

　Vehicles that tilt the vehicle body when turning are proposed. In addition, a vehicle has been proposed in which the front wheels are naturally steered in the direction in which the vehicle body tilts.

JP, 2013-233895, A JP, 2013-023017, A International Publication No. 2017/164342 International Publication No. 2017/090666 Japanese Patent No. 5936306

When the vehicle speed is slow, the change in the steering angle (and by extension the direction of the wheels) may be delayed with respect to the change in the body inclination. When a driving device for steering such as a motor steers the wheels, delay in the change in the direction of the wheels is suppressed. However, when a failure occurs in the steering drive device, it is difficult to suppress the delay in the change in the direction of the wheels.

The present specification discloses a technique capable of suppressing the delay in the change in the direction of the wheels with respect to the change in the inclination of the vehicle body.

The technology disclosed in this specification can be implemented as the following application examples.

[Application example 1]
A vehicle,
The car body,
N (N is an integer of 3 or more) wheels including one or more rotating wheels supported by the vehicle body, the left drive wheel and the right drive wheel being spaced apart from each other in the width direction of the vehicle body. The N wheels, wherein the traveling direction of the one or more rotating wheels is rotatable in the width direction of the vehicle body,
A drive system configured to apply torque to the left drive wheel and the right drive wheel;
A steering drive device configured to generate a torque for rotating the one or more rotating wheels in the width direction;
A tilting device configured to tilt the vehicle body in the width direction,
A tilting drive configured to drive the tilting device,
A vehicle speed sensor configured to measure the vehicle speed of the vehicle,
A wheel angle sensor configured to measure a wheel angle indicating the traveling direction of the one or more rotating wheels with respect to the vehicle body;
An operation input unit configured to be operated to input an operation amount indicating a turning direction and a degree of turning,
A control device configured to control the drive system, the steering drive device, and the tilt drive device;
Equipped with
The control device is
The target wheel angle is specified using the operation amount and the vehicle speed,
When the operation amount indicates a turn, the tilt drive device tilts the vehicle body inward of the turn,
When the vehicle speed is less than a first threshold value and a first condition including that the state of the steering drive device is not a predetermined malfunction state is satisfied, the wheel angle approaches the target wheel angle. Controlling the torque produced by the steering drive,
When the vehicle speed is less than the first threshold and the second condition including the state of the steering drive device is in the defective state is satisfied, the wheel angle approaches the target wheel angle, Controlling the difference between the left torque, which is the torque of the left drive wheel, and the right torque, which is the torque of the right drive wheel, applied by a drive system;
vehicle.

According to this configuration, when the vehicle speed is less than the first threshold value and the first condition including that the state of the steering drive device is not a predetermined malfunction state is satisfied, the wheel angle approaches the target wheel angle. As described above, since the torque generated by the steering drive device is controlled, the delay of the change in the wheel angle with respect to the change in the inclination of the vehicle body is suppressed. Further, when the vehicle speed is less than the first threshold value and the second condition including the condition of the steering drive device is in a defective state is satisfied, the drive system applies the wheel angle so as to approach the target wheel angle. The difference between the left torque of the left drive wheel and the right torque of the right drive wheel is controlled, so that even if the steering drive device is in a defective state, there is a delay in the change of the wheel angle with respect to the change of the vehicle body inclination. Is suppressed.

[Application example 2]
The vehicle according to Application Example 1,
When the ratio of the magnitude of the difference between the left torque and the right torque with respect to the magnitude of the difference between the wheel angle and the target wheel angle is called a torque angle proportion,
When the second condition is satisfied, the control device compares the torque angle ratio when the vehicle speed is faster than a second threshold value with the torque angle ratio when the vehicle speed is slower than the second threshold value. Controlling the difference between the left torque and the right torque to be smaller,
vehicle.

With this configuration, when the vehicle speed is relatively slow, the large difference between the left torque and the right torque suppresses the delay in the change in the wheel angle with respect to the change in the lean of the vehicle body. When the vehicle speed is relatively high, the difference between the left torque and the right torque becomes small, so that a sudden change in the wheel angle can be suppressed.

Note that the technology disclosed in this specification can be implemented in various modes, for example, a mode of a vehicle, a vehicle control device, a vehicle control method, and the like.

FIG. 3 is a right side view of vehicle 10. 2 is a top view of the vehicle 10. FIG. 3 is a bottom view of vehicle 10. FIG. FIG. 3 is a rear view of vehicle 10. (A), (B) is a schematic diagram showing a state of the vehicle 10. (A), (B) is a schematic diagram showing a state of the vehicle 10. It is explanatory drawing of the balance of the force at the time of turning. It is explanatory drawing which shows the simplified relationship between the wheel angle AF and the turning radius R. (A), (B) is explanatory drawing of the torque tqa which acts on the front wheel 12F. It is explanatory drawing of the force which acts on the front wheel 12F which rotates. FIG. 3 is a block diagram showing a configuration related to control of vehicle 10. It is a flow chart which shows an example of control processing. It is a flow chart which shows an example of the 1st inclination control processing. It is a flow chart which shows the example of the 1st steering control processing. It is a graph which shows the example of P gain Kpa. (A), (B) is an explanatory view of movement of vehicle 10. (C) is a graph showing an example of the coefficient Kpb. (D) is a graph showing an example of the relationship between the adjustment value dTQ and the vehicle speed V.

A1. Configuration of vehicle 10:
1 to 4 are explanatory views showing a vehicle 10 as one embodiment. 1 shows a right side view of the vehicle 10, FIG. 2 shows a top view of the vehicle 10, FIG. 3 shows a bottom view of the vehicle 10, and FIG. 4 shows a rear view of the vehicle 10. .. 1 to 4 show a vehicle 10 that is placed on a horizontal ground GL (FIG. 1) and is not tilted. 2 to 4, a part of the configuration of the vehicle 10 shown in FIG. 1 is shown, and the other parts are omitted. Six directions DF, DB, DU, DD, DR and DL are shown in FIGS. 1 to 4. The front direction DF is the front direction (that is, the forward direction) of the vehicle body 90 of the vehicle 10, and the rear direction DB is the direction opposite to the front direction DF. The upward direction DU is a vertically upward direction, and the downward direction DD is a direction opposite to the upward direction DU. The right direction DR is the right direction viewed from the vehicle 10 traveling in the front direction DF, and the left direction DL is the direction opposite to the right direction DR. The directions DF, DB, DR, DL are all horizontal directions. The right and left directions DR and DL are perpendicular to the front direction DF.

In the present embodiment, the vehicle 10 is a small vehicle for one passenger. The vehicle 10 (FIGS. 1 and 2) is a tricycle having a vehicle body 90, a front wheel 12F, a left rear wheel 12L, and a right rear wheel 12R. The front wheel 12F is an example of a rotating wheel, and is arranged at the center of the vehicle body 90 in the width direction. The turning wheel is a wheel supported by the vehicle body 90 so that the traveling direction of the wheel can be turned in the width direction of the vehicle body 90 (that is, the direction parallel to the right direction DR). The rear wheels 12L and 12R are drive wheels, and are symmetrically arranged apart from each other with respect to the center of the vehicle body 90 in the width direction.

The vehicle body 90 (FIG. 1) has a main body portion 20. The main body 20 includes a bottom 20b, a front wall 20a connected to the front DF side of the bottom 20b, a rear wall 20c connected to the rear DB side of the bottom 20b, and an upper end of the rear wall 20c. And a support portion 20d extending toward the rear direction DB. The main body 20 has, for example, a metal frame and a panel fixed to the frame.

The vehicle body 90 further includes a seat 11 fixed on the bottom portion 20b, an accelerator pedal 45 and a brake pedal 46 arranged on the front direction DF side of the seat 11, a control device 100 fixed on the bottom portion 20b, and a battery 120. The front wheel support device 41 includes a front wheel support device 41 fixed to an end of the front wall part 20a on the upward DU side, a shift switch 47 attached to the front wheel support device 41, and a handle 41a. Although not shown, other members (for example, a roof, a headlight, etc.) may be fixed to the main body 20. The vehicle body 90 includes a member fixed to the main body section 20.

The shift switch 47 is a switch for selecting the driving mode of the vehicle 10. In the present embodiment, it is possible to select one from four driving modes of "drive", "neutral", "reverse" and "parking". "Drive" is a mode in which the drive wheels 12L, 12R are driven forward, "Neutral" is a mode in which the drive wheels 12L, 12R are rotatable, and "Reverse" is a drive mode for the drive wheels 12L, 12R. "Parking" is a mode in which at least one wheel (for example, the rear wheels 12L, 12R) cannot rotate. “Drive” and “neutral” are normally used when the vehicle 10 moves forward.

The front wheel support device 41 (FIG. 1) is a device that supports the front wheel 12F so as to be rotatable about the rotation axis Ax1. The front wheel support device 41 includes the front fork 17, a bearing 68, and a steering motor 65. The front fork 17 rotatably supports the front wheel 12F, and is, for example, a telescopic type fork having a suspension (a coil spring and a shock absorber) built therein. The bearing 68 connects the main body portion 20 (here, the front wall portion 20a) and the front fork 17. The bearing 68 supports the front fork 17 (and by extension, the front wheel 12F) so as to be rotatable left and right with respect to the vehicle body 90 about the rotation axis Ax1. The front fork 17 may be rotatable about the rotation axis Ax1 with respect to the vehicle body 90 within a predetermined angular range (for example, a range of less than 180 degrees). For example, the front fork 17 may contact another member provided on the vehicle body 90 to limit the angular range. The steering motor 65 is an electric motor, and is an example of a steering drive device configured to generate a torque that rotates the front fork 17 (and thus the front wheel 12F) in the width direction. The steering motor 65 includes a rotor and a stator (not shown). One of the rotor and the stator is fixed to the front fork 17, and the other is fixed to the main body 20 (here, the front wall 20a).

The handle 41a is a member rotatable left and right. The rotation direction (right or left) of the handle 41a with respect to the predetermined straight traveling direction indicates the turning direction desired by the user. The size of the rotation angle of the handle 41a with respect to a predetermined straight traveling direction (hereinafter, also referred to as "handle angle") indicates the degree of turning desired by the user. In the present embodiment, “steering wheel angle=zero” indicates straight ahead, “steering wheel angle>zero” indicates right turn, and “steering wheel angle<zero” indicates left turn. Thus, the positive and negative signs of the steering wheel angle indicate the turning direction. The absolute value of the steering wheel angle indicates the degree of turning. Such a steering wheel angle is an example of an operation amount indicating a turning direction and a turning degree. The handle 41a is an example of an operation input unit configured to be operated to input an operation amount.

In this embodiment, a support rod 41ax extending along the rotation axis of the handle 41a is fixed to the handle 41a. The support rod 41ax is rotatably connected to the front wheel support device 41 about a rotation axis.

The wheel angle AF (FIG. 2) is an angle indicating the direction of the front wheels 12F with respect to the vehicle body 90. In the present embodiment, the wheel angle AF is an angle in the traveling direction D12 of the front wheels 12F with reference to the front direction DF of the vehicle body 90 when the vehicle 10 is viewed in the downward direction DD. The traveling direction D12 is a direction perpendicular to the rotation axis Ax2 of the front wheel 12F. In this embodiment, “AF=0” indicates “direction D12=forward direction DF”. “AF>zero” indicates that the direction D12 faces the right DR side (turning direction=right DR). “AF<zero” indicates that the direction D12 faces the leftward DL side (turning direction=leftward DL). When the front wheels 12F are steered, the wheel angle AF corresponds to a so-called steering angle.

The steering motor 65 is controlled by the control device 100 (FIG. 1). Hereinafter, the torque generated by the steering motor 65 is also referred to as turning torque. When the turning torque is small, the direction D12 of the front wheel 12F is allowed to turn left and right independently of the steering wheel angle. Details of the control of the steering motor 65 will be described later.

The angle CA in FIG. 1 indicates the angle formed by the vertically upward direction DU and the direction toward the vertically upward direction DU side along the rotation axis Ax1 (also called a caster angle). In this embodiment, the caster angle CA is larger than zero. When the caster angle CA is larger than zero, the direction toward the vertically upward direction DU side along the rotation axis Ax1 is inclined rearward.

Further, as shown in FIG. 1, in the present embodiment, an intersection P2 between the rotation axis Ax1 of the front wheel support device 41 and the ground GL is located closer to the front side DF than the contact center P1 of the front wheel 12F with the ground GL. positioned. The distance Lt in the backward direction DB between these points P1 and P2 is called a trail. The positive trail Lt indicates that the contact center P1 is located on the backward DB side with respect to the intersection P2. Note that, as shown in FIGS. 1 and 3, the contact center P1 is the center of gravity of the contact region Ca1 between the front wheel 12F and the ground GL. The center of gravity of the contact area is the position of the center of gravity assuming that the mass is evenly distributed in the contact area. The contact center PbR of the contact region CaR between the right rear wheel 12R and the ground GL and the contact center PbL of the contact region CaL between the left rear wheel 12L and the ground GL are similarly specified.

The two rear wheels 12L and 12R (FIG. 4) are rotatably supported by the rear wheel support portion 80. The rear wheel support portion 80 is fixed to the link mechanism 30, the lean motor 25 fixed to the upper portion of the link mechanism 30, the first support portion 82 fixed to the upper portion of the link mechanism 30, and the front portion of the link mechanism 30. The second supporting portion 83 (FIG. 1) is formed. In FIG. 1, for explanation, a part of the link mechanism 30, the first support portion 82, and the second support portion 83 hidden by the right rear wheel 12R is also shown by a solid line. In FIG. 2, the rear wheel support portion 80, the rear wheels 12L and 12R, and the connecting rod 75, which will be described later, hidden in the main body portion 20 are shown by solid lines for the sake of explanation. 1 to 3, the link mechanism 30 is shown in a simplified manner.

The first support portion 82 (FIG. 4) includes a plate-shaped portion extending parallel to the right direction DR on the upward DU side of the rear wheels 12L and 12R. The second support portion 83 (FIGS. 1 and 2) is arranged on the front direction DF side of the link mechanism 30 between the left rear wheel 12L and the right rear wheel 12R.

The right rear wheel 12R (FIG. 1) has a wheel 12Ra and a tire 12Rb mounted on the wheel 12Ra. The wheel 12Ra (FIG. 4) is connected to the right drive motor 51R. The right drive motor 51R is an electric motor having a stator and a rotor (not shown). One of the rotor and the stator is fixed to the wheel 12Ra, and the other is fixed to the rear wheel support portion 80. The rotation axis of the right drive motor 51R is the same as the rotation axis of the wheel 12Ra, and is parallel to the right direction DR. The configuration of the wheel 12La of the left rear wheel 12L, the tire 12Lb, and the left drive motor 51L is the same as the configuration of the wheel 12Ra, the tire 12Rb, and the right drive motor 51R of the right rear wheel 12R, respectively. These drive motors 51L and 51R are in-wheel motors that directly drive the rear wheels 12L and 12R. Hereinafter, the left drive motor 51L and the right drive motor 51R are collectively referred to as a drive system 51S. 1 and 4 show a state in which the vehicle body 90 stands upright on the horizontal ground GL without tilting (a state in which a tilt angle T described later is zero). In this state, the rotation axis ArL of the left rear wheel 12L (FIG. 4) and the rotation axis ArR of the right rear wheel 12R are located on the same straight line. As shown in FIGS. 1 and 3, the position in the front direction DF is approximately the same between the contact center PbR of the right rear wheel 12R and the contact center PbL of the left rear wheel 12L.

The link mechanism 30 (FIG. 4) is a so-called parallel link. The link mechanism 30 includes three vertical link members 33L, 21, 33R arranged in order in the right direction DR, and two horizontal link members 31U, 31D arranged in order in the downward direction DD. .. When the vehicle body 90 stands upright on the horizontal ground GL without tilting, the vertical link members 33L, 21, 33R are parallel to the vertical direction, and the horizontal link members 31U, 31D are parallel to the horizontal direction. .. The two vertical link members 33L and 33R and the two horizontal link members 31U and 31D form a parallelogram link mechanism. The upper horizontal link member 31U connects the upper ends of the vertical link members 33L and 33R. The lower horizontal link member 31D connects the lower ends of the vertical link members 33L and 33R. The middle vertical link member 21 connects the central portions of the horizontal link members 31U and 31D. The link members 33L, 33R, 31U, 31D, 21 are rotatably connected to each other, and the rotation axis extends in the front-rear direction of the vehicle body 90 (in the present embodiment, the rotation axis is the forward direction DF). Parallel to). The link members connected to each other may be relatively rotatable about the rotation axis within a predetermined angular range (for example, a range less than 180 degrees). For example, a certain portion of one link member may contact a certain portion of the other link member to limit the angular range. The left drive motor 51L is fixed to the left vertical link member 33L. The right drive motor 51R is fixed to the right vertical link member 33R. A first support portion 82 and a second support portion 83 (FIG. 1) are fixed to the upper portion of the middle vertical link member 21. The link members 33L, 21, 33R, 31U, 31D and the supporting portions 82, 83 are made of metal, for example.

In this embodiment, the link mechanism 30 has a bearing for rotatably connecting a plurality of link members. For example, the bearing 38 rotatably connects the lower horizontal link member 31D and the middle vertical link member 21, and the bearing 39 rotatably connects the upper horizontal link member 31U and the middle vertical link member 21. Although not described, bearings are also provided in other portions that rotatably connect the plurality of link members.

The lean motor 25 is an example of a tilt drive device configured to drive the link mechanism 30, and is an electric motor having a stator and a rotor in this embodiment. One of the stator and the rotor of the lean motor 25 is fixed to the middle vertical link member 21 and the other is fixed to the upper horizontal link member 31U. The rotation shaft of the lean motor 25 is the same as the rotation shaft of the bearing 39, and is located at the center of the vehicle 10 in the width direction. When the rotor of the lean motor 25 rotates with respect to the stator, the upper horizontal link member 31U rotates with respect to the middle vertical link member 21. As a result, the vehicle 10 tilts. Hereinafter, the torque generated by the lean motor 25 is also referred to as tilt torque. The tilt torque is a torque for controlling the tilt angle of the vehicle body 90.

5A and 5B are schematic diagrams showing the state of the vehicle 10 on the horizontal ground GL. In the figure, a simplified rear view of the vehicle 10 is shown. FIG. 5(A) shows a state in which the vehicle 10 is upright, and FIG. 5(B) shows a state in which the vehicle 10 is inclined. As shown in FIG. 5(A), when the upper horizontal link member 31U is orthogonal to the middle vertical link member 21, all the wheels 12F, 12L, 12R stand upright on the horizontal ground GL. The entire vehicle 10 including the vehicle body 90 stands upright with respect to the ground GL. The vehicle body upward direction DVU in the drawing is the upward direction of the vehicle body 90. When the vehicle 10 is not inclined, the vehicle body upward direction DVU is the same as the upward direction DU. In this embodiment, a predetermined upward direction with respect to the vehicle body 90 is used as the vehicle body upward direction DVU.

The lateral link members 31U and 31D are members rotatably supported by the vehicle body 90 (specifically, the lateral link members 31U and 31D are the vehicle body via a suspension system 70 and a first support portion 82, which will be described later. 90 is rotatably supported by the intermediate vertical link member 21 connected to 90). The link mechanism 30 including the lateral link members 31U and 31D can change the relative position of the left rear wheel 12L and the right rear wheel 12R in the vehicle body upward direction DVU. As shown in FIG. 5B, in the rear view, when the middle vertical link member 21 is rotating clockwise with respect to the upper horizontal link member 31U, the right rear wheel 12R is on the vehicle body upward direction DVU side. The left rear wheel 12L moves to the opposite side. As a result, with all the wheels 12F, 12L, 12R in contact with the ground GL, these wheels 12F, 12L, 12R incline to the right DR side with respect to the ground GL. Then, the entire vehicle 10, including the vehicle body 90, inclines to the right DR side with respect to the ground GL. Generally, when the upper horizontal link member 31U inclines with respect to the middle vertical link member 21, one of the right rear wheel 12R and the left rear wheel 12L moves to the vehicle body upward direction DVU side, and the other one It moves to the opposite side of the upward DVU. As a result, the wheels 12F, 12L, 12R, and thus the entire vehicle 10 including the vehicle body 90 are inclined with respect to the ground GL. As described later, when the vehicle 10 turns to the right DR side, the vehicle 10 leans to the right DR side. When the vehicle 10 turns leftward DL, the vehicle 10 leans leftward DL.

In FIG. 5(B), the vehicle body upward direction DVU is inclined to the right side DR side with respect to the upward direction DU. Hereinafter, the angle between the upward direction DU and the vehicle body upward direction DVU when the vehicle 10 is viewed in the front direction DF is referred to as a tilt angle T. Here, “T>zero” indicates an inclination toward the right side DR side, and “T<zero” indicates an inclination toward the left side DL side. When the vehicle 10 leans, the entire vehicle 10 including the vehicle body 90 leans approximately in the same direction. Therefore, the inclination angle T of the vehicle body 90 can be said to be the inclination angle T of the vehicle 10.

Further, FIG. 5(B) shows the control angle Tc of the link mechanism 30. The control angle Tc indicates the angle of the orientation of the middle vertical link member 21 with respect to the orientation of the upper horizontal link member 31U. “Tc=zero” indicates that the middle vertical link member 21 is perpendicular to the upper horizontal link member 31U. “Tc>zero” indicates that, in the rear view of FIG. 5B, the middle vertical link member 21 rotates clockwise with respect to the upper horizontal link member 31U. Although not shown, “Tc<zero” indicates that the middle vertical link member 21 has rotated counterclockwise with respect to the upper horizontal link member 31U. As illustrated, when the vehicle 10 is located on the horizontal ground GL (that is, the ground GL perpendicular to the vertically upward direction DU), the control angle Tc is approximately the same as the tilt angle T.

The axis AxL on the ground GL in FIGS. 5A and 5B is the tilt axis AxL. The link mechanism 30 and the lean motor 25 can tilt the vehicle 10 to the right and left around the tilt axis AxL. In this embodiment, the tilt axis AxL is a straight line that passes through the contact center P1 between the front wheel 12F and the ground GL and is parallel to the front direction DF. The link mechanism 30 that rotatably supports the rear wheels 12L and 12R is an example of a tilting device configured to tilt the vehicle body 90 in the width direction of the vehicle body 90 (also referred to as a tilting device 30).

6(A) and 6(B) show a simplified rear view of the vehicle 10, similar to FIGS. 5(A) and 5(B). In FIG. 6A and FIG. 6B, the ground GLx is inclined with respect to the vertically upward direction DU (the right side is high and the left side is low). FIG. 6A shows a state in which the control angle Tc is zero. In this state, all the wheels 12F, 12L, 12R stand upright with respect to the ground GLx. The vehicle body upward direction DVU is perpendicular to the ground surface GLx, and is inclined to the left direction DL side with respect to the vertically upward direction DU.

FIG. 6B shows a state where the tilt angle T is zero. In this state, the upper horizontal link member 31U is substantially parallel to the ground GLx, and is inclined in the counterclockwise direction with respect to the middle vertical link member 21. The wheels 12F, 12L, 12R are inclined with respect to the ground GL.

In this way, when the ground GLx is inclined, the size of the inclination angle T of the vehicle body 90 may be different from the size of the control angle Tc of the link mechanism 30.

Note that the lean motor 25 has a lock mechanism (not shown) that fixes the lean motor 25 so that it cannot rotate. By operating the lock mechanism, the upper horizontal link member 31U is non-rotatably fixed to the middle vertical link member 21. As a result, the control angle Tc is fixed. For example, the control angle Tc is fixed to zero when the vehicle 10 is parked. The lock mechanism is preferably a mechanical mechanism that does not consume power while fixing the lean motor 25 (and thus the link mechanism 30).

As shown in FIGS. 2 and 4, in the present embodiment, the main body 20 is connected to the rear wheel support 80 by the suspension system 70 and the connecting rod 75. The suspension system 70 (FIG. 4) includes an extendable left suspension 70L and an extendable right suspension 70R. In the present embodiment, each of the suspensions 70L and 70R is a telescopic type suspension that incorporates coil springs 71L and 71R and shock absorbers 72L and 72R. The upper DU side ends of the suspensions 70L and 70R are rotatably connected to the support portion 20d of the main body 20 (for example, a ball joint, a hinge, etc.). The ends of the suspensions 70L and 70R on the downward DD side are rotatably connected to the first support portion 82 of the rear wheel support portion 80 (for example, a ball joint, a hinge, etc.).

The connecting rod 75 is a rod extending in the forward direction DF, as shown in FIGS. 1 and 2. The connecting rod 75 is arranged at the center of the vehicle 10 in the width direction. An end portion of the connecting rod 75 on the front DF side is rotatably connected to the rear wall portion 20c of the main body portion 20 (for example, a ball joint). The rear DB side end of the connecting rod 75 is rotatably connected to the second support portion 83 of the rear wheel support portion 80 (for example, a ball joint).

The vehicle body 90 can be rotated in the width direction by expanding and contracting the suspensions 70L and 70R. A rotation axis AxR in FIG. 1 indicates a central axis when the vehicle body 90 rotates in the right direction DR and the left direction DL with respect to the rear wheel support portion 80. In the present embodiment, the rotation axis AxR is a straight line passing through the contact center P1 between the front wheel 12F and the ground GL and the vicinity of the connecting rod 75. The vehicle body 90 is rotatable about a rotation axis AxR within a predetermined angle range (for example, a range of less than 90 degrees). In this embodiment, the angular range is limited by the possible range of length of the suspensions 70L, 70R. In this embodiment, the tilt axis AxL of the tilt by the tilt device 30 is different from the rotation axis AxR.

The rotation axis AxR and the center of gravity 90c are shown in FIG. 1, FIG. 5(A), and FIG. 5(B). The rotation axis AxR in FIGS. 5A and 5B indicates the position of the rotation axis AxR on a plane including the suspensions 70L and 70R and perpendicular to the front direction DF. The center of gravity 90c is the center of gravity of the vehicle body 90. The center of gravity 90c of the vehicle body 90 is the center of gravity of the vehicle body 90 when the vehicle body 90 is loaded with passengers (and, if possible, luggage). As illustrated, in the present embodiment, the vehicle 10 is configured such that the center of gravity 90c is arranged on the lower side DD side of the rotation axis AxR. Therefore, when the vehicle body 90 vibrates about the rotation axis AxR, it is possible to suppress the amplitude of vibration from becoming excessively large. In this embodiment, the battery 120, which is a relatively heavy element among the elements of the vehicle body 90 (FIG. 1), is arranged at a low position in order to arrange the center of gravity 90c on the lower side DD side of the rotation axis AxR. There is. Specifically, the battery 120 is fixed to the bottom portion 20b which is the lowest portion of the body portion 20 of the vehicle body 90. Therefore, the center of gravity 90c can be easily made lower than the rotation axis AxR.

FIG. 7 is an explanatory diagram of the force balance during turning. In the drawing, a rear view of the rear wheels 12L and 12R when the turning direction is the right direction is shown. As will be described later, when the turning direction is the right direction, the control device 100 (FIG. 1) leans the rear wheels 12L and 12R (and thus the vehicle 10) in the right direction DR with respect to the ground GL. The motor 25 may be controlled.

The first force F1 in the figure is a centrifugal force that acts on the vehicle body 90. The second force F2 is gravity acting on the vehicle body 90. Here, the mass of the vehicle body 90 is m (kg), the gravitational acceleration is g (approximately 9.8 m/s ² ), and the inclination angle of the vehicle 10 with respect to the vertical direction is T (degrees). Is V (m/s), and the turning radius is R (m). The first force F1 and the second force F2 are represented by the following equations 1 and 2.
^{F1 = (m * V 2)} / R ( Equation 1)
F2 = m*g (Formula 2)
Here, * is a multiplication symbol (hereinafter the same).

The force F1b in the figure is a component of the first force F1 in a direction perpendicular to the vehicle body upward direction DVU. The force F2b is a component of the second force F2 in a direction perpendicular to the vehicle body upward direction DVU. The force F1b and the force F2b are expressed by the following equations 3 and 4.
F1b=F1*cos(T) (Formula 3)
F2b=F2*sin(T) (Equation 4)
Here, “cos( )” is a cosine function, and “sin( )” is a sine function (hereinafter the same).

The force F1b is a component that rotates the vehicle body upward direction DVU to the left direction DL side, and the force F2b is a component that rotates the vehicle body upward direction DVU to the right direction DR side. When the vehicle 10 keeps turning while maintaining the inclination angle T (further, the speed V and the turning radius R), the relationship between F1b and F2b is expressed by the following expression 5: F1b=F2b (expression 5)
By substituting the above equations 1 to 4 into the equation 5, the turning radius R is expressed by the following equation 6.
^{R = V 2 / (g *} tan (T)) ( Equation 6)
Here, “tan( )” is a tangent function (hereinafter the same).
Formula 6 is established without depending on the mass m of the vehicle body 90. Here, the following is obtained by substituting “T” in Expression 6 with a parameter Ta (here, the absolute value of the tilt angle T) representing the magnitude of the tilt angle without distinguishing between the left direction and the right direction. The expression 6a is established regardless of the inclination direction of the vehicle body 90.
^{R = V 2 / (g *} tan (Ta)) ( Equation 6a)

FIG. 8 is an explanatory diagram showing a simplified relationship between the wheel angle AF and the turning radius R. In the figure, the wheels 12F, 12L, 12R as viewed in the downward direction DD are shown. In the figure, the traveling direction D12 of the front wheels 12F is rotating in the right direction DR, and the vehicle 10 turns in the right direction DR. The front center Cf in the figure is the center of the front wheel 12F. The front center Cf is located on the rotation axis Ax2 of the front wheel 12F. When the vehicle 10 is viewed in the downward direction DD, the front center Cf is located at substantially the same position as the contact center P1 (FIG. 1). The rear center Cb is the center between the two rear wheels 12L and 12R. When the vehicle body 90 is not tilted, the rear center Cb is located at the center between the rear wheels 12L and 12R on the rotation axes ArL and ArR of the rear wheels 12L and 12R. When the vehicle 10 is viewed in the downward direction DD, the position of the rear center Cb is the same as the center position between the contact centers PbL and PbR of the two rear wheels 12L and 12R. The center Cr is the center of turning (referred to as the turning center Cr). The wheel base Lh is a distance in the front direction DF between the front center Cf and the rear center Cb. As shown in FIG. 1, the wheel base Lh is the distance in the front direction DF between the rotation axis Ax2 of the front wheel 12F and the rotation axes ArL and ArR of the rear wheels 12L and 12R.

As shown in FIG. 8, the front center Cf, the rear center Cb, and the turning center Cr form a right triangle. The interior angle of the point Cb is 90 degrees. The interior angle of the point Cr is the same as the wheel angle AF. Therefore, the relationship between the wheel angle AF and the turning radius R is expressed by the following Expression 7.
AF = arctan(Lh/R) (Equation 7)
Here, “arctan( )” is the inverse function of the tangent function (hereinafter the same).

The above equations 6, 6a, and 7 are relational expressions that are established when the vehicle 10 is turning in a state where the speed V and the turning radius R do not change. Note that there are various differences between the actual behavior of the vehicle 10 and the simplified behavior of FIG. For example, the real wheels 12F, 12L, 12R may slide against the ground. Further, the actual wheels 12F, 12L, 12R may be inclined with respect to the ground. Therefore, the actual turning radius may be different from the turning radius R in Equation 7. However, Expression 7 can be used as a good approximate expression showing the relationship between the wheel angle AF and the turning radius R.

As will be described later, in this embodiment, the torque of the steering motor 65 (FIG. 1) may be controlled to a small value. Here, when the vehicle 10 leans during forward movement, the direction of the front wheels 12F (that is, the traveling direction D12 (FIG. 2)) is naturally rotatable in the leaning direction.

9(A) and 9(B) are explanatory diagrams of the torque tqa acting on the front wheel 12F. FIG. 9(A) shows an outline of the vehicle 10 as viewed in the downward direction DD, and FIG. 9(B) shows an outline of the front wheels 12F as viewed in the front direction DF. These figures show a state in which the vehicle body 90 of the vehicle 10 moving forward is inclined to the right DR side. In this embodiment, the front wheel support device 41 is fixed to the vehicle body 90 as described with reference to FIG. When the vehicle body 90 leans, the front wheel support device 41 (and by extension, the rotation axis Ax1 of the front wheel 12F) leans together with the vehicle body 90. As shown in FIG. 9B, the front wheel 12F inclines to the right DR side. In this state, the front wheels 12F come into contact with the ground GL to support a part of the weight of the vehicle 10. Therefore, the front wheel 12F receives the force Fa in the upward direction DU from the ground GL. The force Fa acts on the contact center P1 of the front wheel 12F. This force Fa includes a component Fa1 parallel to the rotation axis Ax1 of the front wheel 12F and a component Fa2 perpendicular to the rotation axis Ax1. When the rotation axis Ax1 is inclined to the right side DR side with respect to the vertically upward direction DU, the vertical component Fa2 faces the left direction DL side.

As shown in FIG. 9(A), since the front wheel 12F has a positive trail Lt, the contact center P1 of the front wheel 12F is closer to the rear DB than the intersection P2 between the rotation axis Ax1 of the front wheel 12F and the ground GL. Located on the side. Then, a force Fa2 directed to the left DL side acts on the contact center P1 of the front wheel 12F. Due to this force Fa2, a torque tqa for rotating the direction D12 of the front wheel 12F to the right DR direction acts on the front wheel 12F. With such a torque tqa, the traveling direction D12 of the front wheel 12F can be naturally rotated in the inclination direction of the vehicle body 90.

Further, in the present embodiment, when the vehicle body 90 leans, a force for turning the direction D12 of the front wheel 12F in the leaning direction acts on the front wheels 12F without depending on the trail Lt. FIG. 10 is an explanatory diagram of a force acting on the rotating front wheel 12F. A perspective view of the front wheel 12F is shown in the figure. In the example of FIG. 10, the direction D12 of the front wheel 12F is the same as the front direction DF. The rotation axis Ax2 is a rotation axis of the front wheel 12F. When the vehicle 10 moves forward, the front wheels 12F rotate around this rotation axis Ax2. In the figure, a rotation axis Ax1 of the front wheel support device 41 (FIG. 1) and a front axis Ax3 are shown. The rotation axis Ax1 extends from the upper direction DU side toward the lower direction DD side. The front axis Ax3 is an axis that passes through the center of gravity 12Fc of the front wheel 12F and is parallel to the direction D12 of the front wheel 12F. The rotation axis Ax2 of the front wheel 12F also passes through the center of gravity 12Fc of the front wheel 12F.

As described above, when the vehicle body 90 leans, the rotation axis Ax1 of the front wheel support device 41 also leans together with the vehicle body 90. Therefore, the rotation axis Ax2 of the front wheel 12F also tries to tilt in the same direction. When the vehicle body 90 of the running vehicle 10 leans to the right DR side, the torque Tqx to lean to the right DR side acts on the front wheels 12F that rotate around the rotation axis Ax2. The torque Tqx includes a component of force that tends to incline the front wheel 12F to the right DR side around the front shaft Ax3. Thus, the movement of an object when an external torque is applied to a rotating object is known as precession. For example, a rotating object rotates about an axis that is perpendicular to the axis of rotation and the axis of external torque. In the example of FIG. 10, when the torque Tqx is applied, the rotating front wheel 12F rotates to the right DR side around the rotation axis Ax1 of the front wheel support device 41. Thus, due to the angular momentum of the rotating front wheel 12F, the direction D12 of the front wheel 12F rotates in the tilt direction of the vehicle body 90.

As described above, when the vehicle 10 leans to the right DR side, the traveling direction D12 of the front wheels 12F follows the lean of the vehicle body 90 and turns to the right DR side. Similarly, when the vehicle 10 leans to the left DL side, the direction D12 of the front wheel 12F turns to the left DL side following the tilt of the vehicle body 90. Then, the vehicle 10 travels in a state where the traveling direction D12 of the front wheels 12F is oriented in a direction suitable for the inclination angle T (FIGS. 7 and 8). In this way, the wheel angle AF changes following the change in the tilt angle T of the vehicle body 90. In particular, the force acting on the rotating front wheel 12F described in FIG. 10 is greater as the rotational speed of the front wheel 12F (that is, vehicle speed) is higher. Therefore, when the vehicle speed is high, the delay in the change of the wheel angle AF with respect to the change of the inclination angle T is suppressed as compared with the case where the vehicle speed is low. Further, in this embodiment, the front wheel 12F has a positive trail Lt. Therefore, when the vehicle speed is high, the traveling direction D12 of the front wheels 12F can be more easily oriented in the traveling direction of the vehicle 10 than when the vehicle speed is low.

When the torque of the steering motor 65 is small, the front wheel support device 41 supports the front wheel 12F as follows. That is, the traveling direction D12 of the front wheel 12F can be rotated in the width direction with respect to the vehicle body 90 in accordance with the change in the inclination of the vehicle body 90 regardless of the information input to the handlebar 41a. For example, even when the steering wheel 41a is maintained in the state of going straight, if the inclination angle T of the vehicle body 90 changes to the right, the traveling direction D12 of the front wheels 12F follows the change of the inclination angle T. Then, it can rotate to the right. As described above, even when the operation amount input to the steering wheel 41a is fixed to one value, the wheel angle AF of the front wheels 12F can be changed to various values in accordance with the change in the inclination of the vehicle body 90. Is.

A2. Control of vehicle 10:
FIG. 11 is a block diagram showing a configuration relating to control of the vehicle 10. The vehicle 10 has a configuration relating to control such as a vehicle speed sensor 122, a steering wheel angle sensor 123, a wheel angle sensor 124, a vertical direction sensor 126, an accelerator pedal sensor 145, a brake pedal sensor 146, a shift switch 47, and a control. The apparatus 100, the right drive motor 51R, the left drive motor 51L, the lean motor 25, and the steering motor 65 are included.

The vehicle speed sensor 122 is a sensor that detects the vehicle speed of the vehicle 10. In this embodiment, the vehicle speed sensor 122 is attached to the lower end of the front fork 17 (FIG. 1) and detects the rotation speed of the front wheels 12F, that is, the vehicle speed.

The steering wheel angle sensor 123 is a sensor that detects the direction of the steering wheel 41a (that is, the steering wheel angle). In this embodiment, the handle angle sensor 123 is attached to the support rod 41ax fixed to the handle 41a (FIG. 1).

The wheel angle sensor 124 is a sensor that detects the wheel angle AF of the front wheels 12F. In this embodiment, the wheel angle sensor 124 is attached to the steering motor 65 (FIG. 1).

The vertical direction sensor 126 is a sensor that specifies the vertical downward direction DD. In this embodiment, the vertical direction sensor 126 is fixed to the vehicle body 90 (FIG. 1) (specifically, the rear wall portion 20c). Further, in the present embodiment, the vertical sensor 126 includes an acceleration sensor 126a, a gyro sensor 126g, and a control unit 126c. The acceleration sensor is a sensor that detects acceleration in an arbitrary direction, and is, for example, a triaxial acceleration sensor. Hereinafter, the direction of acceleration detected by the acceleration sensor 126a is referred to as a detection direction. When the vehicle 10 is stopped, the detection direction is the same as the vertically downward direction DD. The gyro sensor 126g is a sensor that detects angular acceleration about a rotation axis in an arbitrary direction, and is, for example, a triaxial angular acceleration sensor. The control unit 126c is a device that specifies the vertically downward direction DD using the signal from the acceleration sensor 126a, the signal from the gyro sensor 126g, and the signal from the vehicle speed sensor 122. The control unit 126c is, for example, a data processing device including a computer.

The control unit 126c calculates the acceleration of the vehicle 10 by using the vehicle speed V specified by the vehicle speed sensor 122. Then, the control unit 126c identifies the deviation in the detection direction with respect to the vertically downward direction DD caused by the acceleration of the vehicle 10 by using the acceleration (for example, the deviation in the front direction DF or the rear direction DB in the detection direction is identified. ). Further, the control unit 126c uses the angular acceleration specified by the gyro sensor 126g to specify the deviation of the detection direction from the vertically downward direction DD caused by the angular acceleration of the vehicle 10 (for example, the right direction DR of the detection direction). Alternatively, the shift in the left direction DL is specified). The control unit 126c identifies the vertically downward direction DD by correcting the detection direction using the identified deviation. In this way, the vertical direction sensor 126 can specify the appropriate vertical downward direction DD in various traveling states of the vehicle 10.

The accelerator pedal sensor 145 is attached to the accelerator pedal 45 (FIG. 1) and detects the accelerator operation amount. The brake pedal sensor 146 is attached to the brake pedal 46 (FIG. 1) and detects the brake operation amount.

Each of the sensors 122, 123, 124, 145, 146 is composed of, for example, a resolver or an encoder.

The control device 100 has a main control unit 110, a drive device control unit 300, a lean motor control unit 400, and a steering motor control unit 500. The control device 100 operates using electric power from the battery 120 (FIG. 1). In this embodiment, each of the control units 110, 300, 400 and 500 has a computer. Specifically, the control units 110, 300, 400, 500 include processors 110p, 300p, 400p, 500p (for example, CPU), volatile storage devices 110v, 300v, 400v, 500v (for example, DRAM), and nonvolatile memory. The storage devices 110n, 300n, 400n, and 500n (for example, flash memory). Programs 110g, 300g, 400g, 500g for operating the corresponding control units 110, 300, 400, 500 are stored in advance in the nonvolatile storage devices 110n, 300n, 400n, 500n. In addition, map data MT, MAF, MTQ, and MKb are stored in advance in the nonvolatile storage device 110n of the main control unit 110. The map data Mp2 is stored in advance in the nonvolatile memory device 300n of the drive device controller 300. The map data Mp1 and MKpa are stored in advance in the nonvolatile storage device 500n of the steering motor control unit 500. The processors 110p, 300p, 400p, 500p execute various processes by executing the corresponding programs 110g, 300g, 400g, 500g, respectively.

The processor 110p of the main control unit 110 receives signals from the sensors 122, 123, 124, 126, 145, 146 and the shift switch 47. Then, the processor 110p outputs an instruction to the drive device controller 300, the lean motor controller 400, and the steering motor controller 500 using the received signal.

The processor 300p of the drive device controller 300 controls the drive motors 51L and 51R according to an instruction from the main controller 110. The processor 400p of the lean motor control unit 400 controls the lean motor 25 according to an instruction from the main control unit 110. The processor 500p of the steering motor control unit 500 controls the steering motor 65 according to an instruction from the main control unit 110. These control units 300, 400, 500 have power control units 300c, 400c, 500c for supplying electric power from the battery 120 to the control target motors 51L, 51R, 25, 65, respectively. The power control units 300c, 400c, 500c are configured by using an electric circuit (for example, an inverter circuit).

Hereinafter, the fact that the processors 110p, 300p, 400p, 500p of the control units 110, 300, 400, 500 execute processing is also expressed simply as the control units 110, 300, 400, 500 executing processing.

FIG. 12 is a flowchart showing an example of control processing executed by the control device 100 (FIG. 11). The flowchart of FIG. 12 shows the control procedure of the rear wheel support portion 80, the front wheel support device 41, and the drive system 51S. In FIG. 12, each step is provided with a code that is a combination of the letter “S” and the number following the letter “S”.

In S110, the main control unit 110 acquires signals from the sensors 122, 123, 124, 126, 145, 146 and the shift switch 47. Then, the main control unit 110 specifies the speed V, the steering wheel angle Ai, the wheel angle AF, the vertically downward direction DD, the accelerator operation amount, the brake operation amount, and the traveling mode.

In S120, the main control unit 110 determines whether or not the condition "the driving mode is either "drive" or "neutral"" is satisfied. The condition of S120 indicates that the vehicle 10 is moving forward.

If the determination result of S120 is Yes, the control device 100 executes S130 and S140 in parallel. S130 is a first tilt control process for controlling the lean motor 25. S140 is a second steering drive control process for controlling the steering motor 65 and the drive motors 51L and 51R. After S130 and S140, the control device 100 ends the process of FIG.

FIG. 13 is a flowchart showing an example of the first tilt control process (S130: FIG. 12). In S210, the main control unit 110 (FIG. 11) acquires information indicating the vehicle speed V, the steering wheel angle Ai, and the vertically downward direction DD from the sensors 122, 123, and 126, respectively.

In S220, the main control unit 110 (FIG. 11) calculates the tilt angle T using the vertically downward direction DD. In the present embodiment, since the vertical direction sensor 126 is fixed to the vehicle body 90, the direction of the vertical direction sensor 126 with respect to the vehicle body 90 (and thus the vehicle body upward direction DVU) is predetermined. The main controller 110 uses the orientation of the vertical direction sensor 126 with respect to the vehicle body upward direction DVU to determine the inclination angle T between the upward direction DU, which is the direction opposite to the vertically downward direction DD, and the vehicle body upward direction DVU. Calculate (FIG. 5(B)).

The vertical sensor 126 (FIG. 11) and the main controller 110 as a whole are examples of the tilt angle sensor configured to measure the tilt angle T. Hereinafter, the vertical direction sensor 126 and the main control unit 110 as a whole are also referred to as a tilt angle sensor 127.

In S230 (FIG. 13), the main control unit 110 determines the first target tilt angle T1. The first target tilt angle T1 is a target value of the tilt angle T. In the present embodiment, the first target tilt angle T1 is specified using the steering wheel angle Ai and the vehicle speed V. The correspondence relationship between the steering wheel angle Ai, the vehicle speed V, and the first target tilt angle T1 is predetermined by the tilt angle map data MT (FIG. 11). The main control unit 110 identifies the first target tilt angle T1 corresponding to the combination of the steering wheel angle Ai and the vehicle speed V by referring to the tilt angle map data MT. In this embodiment, when the vehicle speed V is constant, the larger the absolute value of the steering wheel angle Ai, the larger the absolute value of the first target tilt angle T1. As a result, the turning radius R decreases as the absolute value of the steering wheel angle Ai increases, so that the vehicle 10 can turn with the turning radius R suitable for the steering wheel angle Ai. The correspondence relationship between the vehicle speed V and the first target tilt angle T1 when the steering wheel angle Ai is constant may be various correspondence relationships. For example, the slower the vehicle speed V, the larger the absolute value of the first target tilt angle T1 may be. In this case, the vehicle 10 can easily turn with a small turning radius R at low speed. Instead, the absolute value of the first target tilt angle T1 may be smaller as the vehicle speed V is slower. In this case, it is possible to suppress an excessive change in the tilt angle T at low speed. The information used for specifying the first target tilt angle T1 may be one or more arbitrary information including the steering wheel angle Ai instead of the combination of the steering wheel angle Ai and the vehicle speed V. For example, the first target tilt angle T1 may be specified without using the vehicle speed V.

In S240, main controller 110 (FIG. 13) calculates difference dT by subtracting tilt angle T from first target tilt angle T1 (also referred to as tilt angle difference dT).

In step S250, the main control unit 110 supplies the lean motor control unit 400 with an instruction to control the lean motor 25 so that the tilt angle difference dT becomes zero. For example, the main control unit 110 supplies information indicating the tilt angle difference dT to the lean motor control unit 400. According to the instruction, the lean motor control unit 400 drives the lean motor 25 so that the tilt angle difference dT becomes zero. The lean motor control unit 400 performs feedback control of the torque of the lean motor 25 (for example, the power supplied to the lean motor 25) using the tilt angle difference dT. As a result, the tilt angle T approaches the first target tilt angle T1. Then, the process of FIG. 13, that is, S130 of FIG. 12 ends. As the feedback control, so-called PID (Proportional Integral Derivative) control is performed, for example.

FIG. 14 is a flowchart showing an example of the first steering control process (S140: FIG. 12). In S310, the main control unit 110 provides the information indicating the vehicle speed V, the steering wheel angle Ai, the wheel angle AF, the accelerator operation amount from the sensors 122, 123, 124, 145 and the information indicating the first target inclination angle T1. Get each. As the first target tilt angle T1, the first target tilt angle T1 determined in S230 of FIG. 13 is acquired.

In S320, the main control unit 110 determines a target wheel angle AFt which is a target value of the wheel angle AF. In the present embodiment, the target wheel angle AFt is specified using the vehicle speed V and the first target tilt angle T1. The target wheel angle AFt corresponding to the combination of the vehicle speed V and the first target tilt angle T1 is a wheel specified by using the combination of the vehicle speed V and the first target tilt angle T1 and the above-described equations 6 and 7. Same as corner AF. The correspondence relationship between the vehicle speed V, the first target tilt angle T1 and the target wheel angle AFt is predetermined by the wheel angle map data MAF (FIG. 11). The main control unit 110 identifies the target wheel angle AFt by referring to this wheel angle map data MAF.

The same target wheel angle AFt can be specified using the steering wheel angle Ai and the vehicle speed V. For example, the wheel angle map data MAF may indicate the correspondence between the combination of the steering wheel angle Ai and the vehicle speed V and the target wheel angle AFt. Then, the main control unit 110 may specify the target wheel angle AFt using the steering wheel angle Ai and the vehicle speed V.

In S330 (FIG. 14), the main control unit 110 calculates the difference dAF by subtracting the wheel angle AF from the target wheel angle AFt (also referred to as wheel angle difference dAF).

At S340, main controller 110 determines whether or not the state of steering motor 65 is a predetermined malfunction state. The defective state may be various states in which the steering motor 65 may have a defective state. In the present embodiment, the defective state is a state in which the magnitude of the current flowing through the steering motor 65 is outside the appropriate range that is associated in advance with the voltage applied to the steering motor 65. When the electric wire (for example, coil wire) of the steering motor 65 is broken, the magnitude of the current flowing through the steering motor 65 may be zero regardless of the voltage. Further, when an unintended short circuit is formed in the electric circuit of the steering motor 65, the magnitude of the current flowing through the steering motor 65 may be excessive.

The electric power control unit 500c of the steering motor control unit 500 (FIG. 11) is configured to measure a voltage applied to the steering motor 65 and a voltmeter configured to measure a current flowing through the steering motor 65. And an ammeter which is operated (not shown). The correspondence between the voltage and the proper range is predetermined by the map data Mp1. The steering motor control unit 500 specifies the appropriate range corresponding to the voltage measured by the voltmeter by referring to the map data Mp1. Then, the steering motor control unit 500 specifies whether or not the current measured by the ammeter is within the proper range, and notifies the main control unit 110 of the specified result. The main control unit 110 uses information from the steering motor control unit 500 to determine whether the state of the steering motor 65 is normal.

Note that the main control unit 110 may store defect information (for example, flag data) indicating whether or not the state of the steering motor 65 is in a defective state in the nonvolatile storage device 110n. The failure information is set to either a normal value indicating that the status is not a failure status or an abnormal value indicating that the status is a failure status. When the vehicle 10 is shipped, the defect information is initialized to a normal value. When the steering motor control unit 500 notifies the main control unit 110 that the current is out of the proper range, the main control unit 110 sets the defect information to an abnormal value. After that, when the steering motor 65 is repaired, the main control unit 110 sets the defect information to the normal value according to the user's instruction. After the fault information is once set to an abnormal value, the main control unit 110 sets the fault information to a normal value even if the steering motor control unit 500 notifies that the current is within the proper range. Do not set to. Then, the main control unit 110 continues to determine that the state of the steering motor 65 is in the defective state until the defective information is set to the normal value in accordance with the user's instruction.

When it is determined that the state of the steering motor 65 is not in the defective state (S340: No), the main control unit 110 executes S350 and S360 in parallel. S350 is a process of controlling the drive motors 51L and 51R. S360 is a process for controlling the steering motor 65. After S350 and S360, the main control unit 110 ends the processing of FIG.

In S350, the main control unit 110 (FIG. 11) uses the accelerator operation amount to specify the target torque of the drive motors 51L and 51R. In the present embodiment, the correspondence relationship between the accelerator operation amount and the target torque is predetermined by the torque map data MTQ. The main control unit 110 identifies the target torque corresponding to the accelerator operation amount by referring to the torque map data MTQ. The larger the accelerator operation amount, the larger the target torque. The target torque may be specified by using the changing speed of the accelerator operation amount in addition to the accelerator operation amount. For example, when the accelerator operation amount is the same, the target torque may be set to a larger value as the increasing speed of the accelerator operation amount is larger.

The main controller 110 supplies the drive device controller 300 with an instruction for controlling the drive motors 51L and 51R so that the torque of the drive motors 51L and 51R becomes the target torque. For example, the main control unit 110 supplies information indicating the target torque to the drive device control unit 300. The drive device controller 300 supplies electric power corresponding to the target torque to the drive motors 51L and 51R according to the instruction. With the above, S350 ends.

The correspondence between the target torque and the electric power is predetermined by the map data Mp2 (FIG. 11). The drive device controller 300 specifies the electric power corresponding to the target torque by referring to the map data Mp2, and supplies the specified electric power to the drive motors 51L and 51R. The drive device controller 300 may specify the electric power using one or more parameters including the target torque (for example, the target torque, the vehicle speed V, etc.). For example, when the target torque is the same, the electric power may be larger as the vehicle speed V is higher.

In S360 (FIG. 14), the main control unit 110 (FIG. 11) supplies the steering motor control unit 500 with an instruction to control the steering motor 65 so that the wheel angle AF becomes the target wheel angle AFt. For example, the main control unit 110 supplies the steering motor control unit 500 with information indicating the wheel angle difference dAF. According to the instruction, the steering motor control unit 500 drives the steering motor 65 so that the wheel angle difference dAF becomes zero. The steering motor control unit 500 performs feedback control of the torque of the steering motor 65 using the wheel angle difference dAF (for example, so-called PID (Proportional Integral Derivative) control). As a result, the wheel angle AF approaches the target wheel angle AFt. Then, the process of S360 ends.

In this embodiment, in S360, P control of the torque (more specifically, electric power) of the steering motor 65 is performed (D control and I control are omitted). The steering motor control unit 500 calculates the control value by multiplying the wheel angle difference dAF by the P gain. Then, the steering motor control unit 500 adjusts the electric power supplied to the steering motor 65 so that the torque of the steering motor 65 is proportional to the control value. Thus, the P gain indicates the ratio of the magnitude of the torque of the steering motor 65 to the magnitude of the wheel angle difference dAF.

FIG. 15 is a graph showing an example of the P gain Kpa used for P control. The horizontal axis represents the vehicle speed V, and the vertical axis represents the P gain Kpa. As illustrated, when the vehicle speed V is equal to or higher than the first threshold value V1, the P gain Kpa is set to zero (zero<V1). When the vehicle speed V is less than the first threshold value V1, the P gain Kpa is greater than zero. When the vehicle speed V is equal to or lower than the second threshold value V2, the P gain Kpa is set to a value Kpa1 larger than zero (zero<V2<V1). Between the first threshold value V1 and the second threshold value V2, the P gain Kpa gradually decreases from the value Kpa1 to zero as the vehicle speed V increases.

As described with reference to FIGS. 9A, 9B, and 10, the traveling direction D12 of the front wheels 12F can naturally rotate in the inclination direction of the vehicle body 90. In particular, in this embodiment, since the front wheel 12F (FIG. 1) has the positive trail Lt, when the vehicle speed V is high, the direction D12 of the front wheel 12F (that is, the wheel angle AF) follows the change of the inclination angle T. Change easily. When the vehicle speed V is equal to or higher than the first threshold value V1, the first threshold value V1 can be easily changed in the direction D12 of the front wheels 12F by following the change of the inclination angle T without using the force of the steering motor 65. Has been determined experimentally in advance (for example, V1=20 km/h). In this embodiment, since the P gain Kpa is zero when the vehicle speed V is equal to or higher than the first threshold value V1, the torque of the steering motor 65 is approximately zero regardless of the wheel angle difference dAF. As a result, the steering motor control unit 500 allows the direction D12 of the front wheels 12F to rotate left and right independently of the steering wheel angle. The traveling direction D12 of the front wheel 12F can be changed following the change in the inclination angle T. Further, when the vehicle speed V is less than the first threshold value V1, the P gain Kpa is larger than zero, so the torque of the steering motor 65 can be large. The large torque of the steering motor 65 brings the direction D12 of the front wheels 12F (that is, the wheel angle AF) closer to the target wheel angle AFt. Further, between the first threshold value V1 and the second threshold value V2, the P gain Kpa changes smoothly according to the change in the vehicle speed V. The second threshold V2 is experimentally determined in advance so that the direction D12 of the front wheels 12F appropriately approaches the direction suitable for the inclination angle T at various vehicle speeds V equal to or lower than the first threshold V1 (for example, V2=10 km/h).

The correspondence between the vehicle speed V and the P gain Kpa is predetermined by the map data MKpa (FIG. 11). The steering motor control unit 500 specifies the P gain Kpa by referring to the map data MKpa, and uses the P gain Kpa to determine the power to be supplied to the steering motor 65. Note that in S360 (FIG. 14), at least one of D control and I control may be performed in addition to P control.

When it is determined that the state of the steering motor 65 is in the defective state (FIG. 14: S340: Yes), the main control unit 110 executes S370 and S380-S390 in parallel. In S370, the main control unit 110 supplies the steering motor control unit 500 with an instruction to stop the power supply to the steering motor 65. The steering motor control unit 500 sets the electric power supplied to the steering motor 65 to zero in response to the instruction. As a result, the steering motor control unit 500 allows the direction D12 of the front wheels 12F to rotate left and right independently of the steering wheel angle. S380-S390 are processes for controlling the drive motors 51L and 51R. After S370 and S380-S390, the main control unit 110 ends the processing of FIG.

In S380, the main control unit 110 identifies the reference torque TQs of the drive motors 51L and 51R using the accelerator operation amount. The reference torque TQs is the same as the target torque specified in S350.

In S385, the main control unit 110 identifies the coefficient Kpb using the vehicle speed V (details will be described later). Then, the main control unit 110 calculates the adjustment value dTQ by multiplying the wheel angle difference dAF by the coefficient Kpb (dTQ=Kpb*dAF). In S390, the main control unit 110 calculates a left target torque TQL that is the target torque of the left drive motor 51L and a right target torque TQR that is the target torque of the right drive motor 51R. These target torques TQL and TQR are calculated using the reference torque TQs and the adjustment value dTQ according to the following formulas.
TQL=TQs+dTQ/2
TQR=TQs-dTQ/2
The adjustment value dTQ is an index value indicating the difference (TQL-TQR=dTQ) between the left target torque TQL and the right target torque TQR. The main controller 110 supplies the drive device controller 300 with an instruction to control the drive motors 51L and 51R so that the torques of the drive motors 51L and 51R become the target torques TQL and TQR. For example, the main control unit 110 supplies information indicating the target torques TQL and TQR to the drive device control unit 300. The drive device control unit 300 supplies electric power corresponding to the target torques TQL and TQR to the drive motors 51L and 51R according to the instruction. The electric power of the left drive motor 51L and the electric power of the right drive motor 51R are specified using the target torques TQL and TQR, similarly to the electric power specified in S350. With the above, S390 ends.

16(A) and 16(B) are explanatory views of the movement of the vehicle 10. In each drawing, the outline of the vehicle 10 as viewed in the vertically downward direction DD is shown. FIG. 16A shows the case where the adjustment value dTQ is a positive value. The target direction D12t in the figure is the target direction of the front wheel 12F indicated by the target wheel angle AFt. When the adjustment value dTQ is a positive value, the wheel angle difference dAF is a positive value, and the target direction D12t faces the right side DR side of the traveling direction D12 of the front wheels 12F. When the adjustment value dTQ is a positive value, TQL>TQR. Since the torque of the left rear wheel 12L is larger than the torque of the right rear wheel 12R, the traveling direction of the vehicle 10 changes to the right direction DR side. As a result, the wheel angle AF approaches the target wheel angle AFt.

FIG. 16B shows a case where the adjustment value dTQ is a negative value. When the adjustment value dTQ is a negative value, the wheel angle difference dAF is a negative value, and the target direction D12t faces the left direction DL side with respect to the traveling direction D12. When the adjustment value dTQ is a negative value, TQR>TQL. Since the torque of the right rear wheel 12R is larger than the torque of the left rear wheel 12L, the traveling direction of the vehicle 10 changes to the left direction DL side. As a result, the wheel angle AF approaches the target wheel angle AFt.

In this way, the traveling direction of the vehicle 10 can be controlled by utilizing the torque difference between the left rear wheel 12L and the right rear wheel 12R.

FIG. 16C is a graph showing an example of the coefficient Kpb used to calculate the adjustment value dTQ (FIG. 14: S385). The horizontal axis represents the vehicle speed V, and the vertical axis represents the coefficient Kpb. The shape of the graph of the correspondence relationship between the vehicle speed V and the coefficient Kpb is the same as the shape of the graph of the correspondence relationship between the vehicle speed V and the P gain Kpa shown in FIG. 15. When the vehicle speed V is equal to or higher than the first threshold value V1, the coefficient Kpb is set to zero. When the vehicle speed V is less than the first threshold value V1, the coefficient Kpb is greater than zero. When the vehicle speed V is equal to or lower than the second threshold value V2, the coefficient Kpb is set to a value Kpb1 larger than zero. Between the first threshold value V1 and the second threshold value V2, the coefficient Kpb gradually decreases from the value Kpb1 to zero as the vehicle speed V increases. In the present embodiment, the correspondence between the vehicle speed V and the coefficient Kpb is determined in advance by the coefficient map data MKb (FIG. 11). In S385 (FIG. 14), the main control unit 110 identifies the coefficient Kpb corresponding to the vehicle speed V by referring to this coefficient map data MKb. The thresholds V1 and V2 are the same as the thresholds V1 and V2 described in the graph of FIG. 15, respectively.

FIG. 16D is a graph showing an example of the relationship between the adjustment value dTQ and the vehicle speed V. The horizontal axis represents the vehicle speed V, and the vertical axis represents the absolute value of the adjustment value dTQ. This graph is a graph when the absolute value of the wheel angle difference dAF is larger than zero. As shown in the figure, when the vehicle speed V is equal to or higher than the first threshold value V1, the absolute value of the adjustment value dTQ is set to zero. When the vehicle speed V is less than the first threshold value V1, the absolute value of the adjustment value dTQ is greater than zero. When the vehicle speed V is equal to or lower than the second threshold value V2, the absolute value of the adjustment value dTQ is set to a value dTQ1 larger than zero. Between the first threshold value V1 and the second threshold value V2, the absolute value of the adjustment value dTQ gradually decreases from the value dTQ1 to zero as the vehicle speed V increases.

When the vehicle speed V is equal to or higher than the first threshold value V1, the adjustment value dTQ is zero, so the difference between the left target torque TQL and the right target torque TQR is zero regardless of the wheel angle difference dAF. Further, since the electric power of the steering motor 65 is zero (S370), the traveling direction D12 of the front wheels 12F can be changed following the change of the inclination angle T. The state of the vehicle 10 is the same as the state of the vehicle 10 when the steering motor 65 is not in the defective state (FIG. 14: S340: No) and the vehicle speed V is equal to or higher than the first threshold value V1. The vehicle 10 can travel in a direction suitable for the first target tilt angle T1.

When the vehicle speed V is less than the first threshold value V1, the coefficient Kpb is greater than zero, so the difference in torque between the left rear wheel 12L and the right rear wheel 12R can be large. The large torque difference between the left rear wheel 12L and the right rear wheel 12R brings the traveling direction of the vehicle 10 closer to a direction suitable for the target wheel angle AFt. As a result, the direction D12 of the front wheels 12F, that is, the wheel angle AF approaches the target wheel angle AFt. As described above, even if the steering motor 65 is in a defective state, the vehicle 10 can travel in a direction suitable for the steering wheel angle Ai.

Also, between the first threshold value V1 and the second threshold value V2, the coefficient Kpb changes smoothly according to the change in the vehicle speed V.

As described above, the processes of FIGS. 13 and 14, that is, S130 and S140 of FIG. 12 are performed in parallel. In S120, when the condition that "the driving mode is "drive" or "neutral"" is not satisfied (S120: No), the main control unit 110 executes the processes of S150 and S160 in parallel. ..

The process of S150 is the same as the process of S130. The tilt angle T is controlled to the first target tilt angle T1. The process of S160 is performed similarly to the process when the vehicle speed V is equal to or less than the second threshold value V2 in S140. That is, regardless of the vehicle speed V, the traveling direction of the vehicle 10 is controlled by the steering motor 65 or the torque difference between the rear wheels 12L and 12R.

The processing of FIG. 12 ends in response to the processing of S130, S140 or S150, S160 being executed. The control device 100 repeatedly executes the processing of FIG. When the conditions for executing S130 and S140 are satisfied (S110: Yes), the control device 100 continuously performs the processes of S130 and S140. When the conditions for executing S150 and S160 are satisfied (S110: No), the control device 100 continuously performs the processes of S150 and S160. As a result, the vehicle 10 travels in the traveling direction suitable for the steering wheel angle.

Although not shown, the main control unit 110 (FIG. 11) and the drive device control unit 300 control the drive motors 51L and 51R according to the brake operation amount. When the brake operation amount becomes greater than zero, the main control unit 110 supplies the drive device control unit 300 with an instruction to reduce the torque of the drive motors 51L and 51R. The drive device control section 300 controls the drive motors 51L and 51R so that the torque decreases in accordance with the instruction. It is preferable that vehicle 10 has a brake device that reduces the rotational speed of at least one of all wheels 12F, 12L, 12R by friction. Then, when the user depresses the brake pedal 46, the braking device preferably reduces the rotation speed of at least one wheel.

As described above, in this embodiment, the vehicle 10 (FIGS. 1 to 4 and 11) includes the vehicle body 90, the three wheels 12F, 12L, and 12R, the drive system 51S, the steering motor 65, and the inclination motor. The device 30, the lean motor 25, the vehicle speed sensor 122, the wheel angle sensor 124, the steering wheel 41a, and the control device 100 are provided. The front wheel 12F is an example of a rotating wheel supported by the vehicle body 90 (the traveling direction of the rotating wheel is rotatable in the width direction of the vehicle body 90). The drive system 51S is configured to apply torque to the left rear wheel 12L and the right rear wheel 12R.

As described in S320 of FIG. 14, the control device 100 identifies the target wheel angle AFt using the vehicle speed V and the first target inclination angle T1. As described in S230 of FIG. 13, the control device 100 specifies the first target tilt angle T1 using the steering wheel angle Ai and the vehicle speed V. Therefore, the control device 100 specifies the target wheel angle AFt using the steering wheel angle Ai and the vehicle speed V.

As described in S250 of FIG. 13, the control device 100 controls the lean motor 25 so that the tilt angle difference dT becomes zero. As a result, the tilt angle T approaches the first target tilt angle T1. When the steering wheel angle Ai indicates a turn, the vehicle body 90 leans inward of the turn.

When the vehicle 10 is moving forward (FIG. 12: S120: Yes) and the state of the steering motor 65 is not a predetermined malfunction state (FIG. 14: S340: No), in S360, the control device 100 determines that The torque generated by the steering motor 65 is controlled using P control using the P gain Kpa (FIG. 15). As described in FIG. 15, when the vehicle speed V is less than the first threshold value V1, the torque generated by the steering motor 65 is controlled so that the wheel angle AF approaches the target wheel angle AFt. In this way, when the vehicle speed V is less than the first threshold value V1 and the condition including the condition that the steering motor 65 is not in the defective state (also referred to as the first condition) is satisfied, the wheel angle AF is the target wheel angle. Since the torque generated by the steering motor 65 is controlled so as to approach AFt, the delay in the change in the wheel angle AF with respect to the change in the inclination of the vehicle body 90 is suppressed. The first condition, which is a condition for performing such control, may be various conditions including that the vehicle speed V is less than the first threshold value V1 and the state of the steering motor 65 is not in a defective state. ..

When the vehicle 10 is moving forward (FIG. 12: S120: Yes) and the state of the steering motor 65 is in a defective state (FIG. 14: S340: Yes), the control device 100 drives the left drive in S380-S390. It controls the motor 51L and the right drive motor 51R. In S385, control device 100 determines adjustment value dTQ using wheel angle difference dAF. In S390, control device 100 determines target torques TQL and TQR using adjustment value dTQ, and controls drive motors 51L and 51R according to target torques TQL and TQR. The torque applied to the left rear wheel 12L and the torque applied to the right rear wheel 12R are controlled according to the target torques TQL and TQR. As described with reference to FIGS. 16A to 16D, when the vehicle speed V is less than the first threshold value V1, the adjustment value dTQ (that is, the torque applied to the left rear wheel 12L and the right rear wheel 12R) is adjusted. The difference from the applied torque) is controlled so that the wheel angle AF approaches the target wheel angle AFt. In this way, when the vehicle speed V is less than the first threshold value V1 and the condition (also referred to as the second condition) including the state of the steering motor 65 being in the defective state is satisfied, the wheel angle AF is the target wheel angle. The difference between the torque applied to the left rear wheel 12L and the torque applied to the right rear wheel 12R is controlled so as to approach AFt. Therefore, even if the steering motor 65 is in a defective state, the delay in the change in the wheel angle AF with respect to the change in the inclination of the vehicle body 90 is suppressed. The second condition, which is a condition for performing such control, may be various conditions including that the vehicle speed V is less than the first threshold value V1 and the state of the steering motor 65 is in a defective state. ..

Further, as described in S385 of FIG. 14, the coefficient Kpb is the ratio of the magnitude of the adjustment value dTQ (that is, the torque difference between the left rear wheel 12L and the right rear wheel 12R) to the magnitude of the wheel angle difference dAF. (Hereinafter also referred to as torque angle ratio Kpb). As described in FIG. 16C, the control device 100 sets the torque angle ratio Kpb when the vehicle speed V is faster than the second threshold value V2 and the torque angle ratio Kpb when the vehicle speed V is slower than the second threshold value V2. Set a smaller value compared to. In S390 of FIG. 14, the control device 100 controls the torque of the left rear wheel 12L and the torque of the right rear wheel 12R based on the torque angle ratio Kpb. Thus, when the vehicle speed V is relatively slow, the change in the wheel angle AF is delayed with respect to the change in the inclination of the vehicle body 90 due to the large difference between the torque of the left rear wheel 12L and the torque of the right rear wheel 12R. Is suppressed. When the vehicle speed V is relatively high, the difference between the torque of the left rear wheel 12L and the torque of the right rear wheel 12R becomes small, so that a sudden change in the wheel angle AF can be suppressed.

B. Modification:
(1) The relationship between the P gain Kpa used to control the steering motor 65 (FIG. 14: S360) and the vehicle speed V may be various other relationships instead of the relationship shown in the graph of FIG. For example, when the vehicle speed V is equal to or higher than the first threshold value V1, the P gain Kpa may be larger than zero. Also in this case, the P gain Kpa (and thus the torque of the steering motor 65) is preferably small so that the direction D12 of the front wheels 12F is allowed to rotate in the width direction independently of the steering wheel angle. Further, when the vehicle speed V is equal to or lower than the second threshold value V2, the P gain Kpa may be reduced according to the increase of the vehicle speed V. The control of the steering motor 65 is not limited to P control, but may be various controls for controlling the torque generated by the steering motor 65 such that the wheel angle AF approaches the target wheel angle AFt (for example, feedback control. ). Here, even if the state of the steering motor 65 is not in a defective state, the control device 100 reduces the torque generated by the steering motor 65 to a small torque (when the speed V is equal to or higher than the first threshold value V1). By setting to zero or a torque close to zero, a control mode that allows the traveling direction of the rotating wheel (for example, the traveling direction D12 of the front wheel 12F) to rotate in the width direction regardless of the steering wheel angle is set. It is preferable to have. As a result, the traveling direction of the rotating wheel can be rotated following the change in the inclination angle T.

(2) The relationship between the coefficient Kpb and the vehicle speed V used for the control of the drive system 51S (FIG. 14: S380-S390) is not limited to the relationship in the graph of FIG. Good. For example, when the vehicle speed V is equal to or higher than the first threshold value V1, the coefficient Kpb may be larger than zero. Also in this case, it is preferable that the coefficient Kpb (and thus the absolute value of the adjustment value dTQ) is small so that the direction D12 of the front wheel 12F is allowed to rotate in the width direction independently of the steering wheel angle. Further, when the vehicle speed V is equal to or lower than the second threshold value V2, the coefficient Kpb may be reduced as the vehicle speed V increases. The control of the drive system 51S is not limited to the control using the coefficient Kpb, but may be various controls for controlling the left and right torque difference so that the wheel angle AF approaches the target wheel angle AFt. Here, even when the state of the steering motor 65 is in a defective state, the control device 100 reduces the left-right torque difference to a small value (zero or, if the speed V is equal to or higher than the first threshold value V1). By setting it to a value close to zero), it is preferable to have a control mode that allows the traveling direction of the rotating wheel (for example, the traveling direction D12 of the front wheel 12F) to rotate in the width direction regardless of the steering wheel angle. .. Thereby, the traveling direction of the rotating wheel can be rotated following the change in the inclination angle T.

(3) The control process of the vehicle 10 may be various other processes instead of the processes of FIGS. For example, the target torques TQL and TQR (FIG. 14: S390) use map data indicating a correspondence relationship among a plurality of parameters including the accelerator operation amount, the difference dAF, the left target torque TQL, and the right target torque TQR, May be specified. In any case, the control device 100 sets the torque angle ratio when the vehicle speed V is higher than the second threshold value to be smaller than the torque angle ratio when the vehicle speed V is lower than the second threshold value. It is preferable to control the difference between the torque of the rear wheel 12L and the torque of the right rear wheel 12R. Here, the torque angle ratio is the ratio of the difference between the torque of the left rear wheel 12L and the torque of the right rear wheel 12R with respect to the magnitude of the wheel angle difference dAF. The second threshold is a specific speed that is smaller than the first threshold V1 described above. In S150 and S160 of FIG. 12, instead of the first target tilt angle T1, the second target tilt angle T2 having an absolute value smaller than the absolute value of the first target tilt angle T1 may be used.

(4) Various configurations can be adopted as the total number and the arrangement of the plurality of wheels. For example, the total number of front wheels may be two and the total number of rear wheels may be one. The total number of front wheels may be two and the total number of rear wheels may be two. The left drive wheel and the right drive wheel, which are arranged apart from each other in the width direction of the vehicle body, may be front wheels. Further, the total number of rotating wheels supported by the vehicle body may be an arbitrary number of 1 or more. The rotating wheel may be a rear wheel. Further, the left driving wheel and the right driving wheel may be rotating wheels. Also, the plurality of wheels may include one or more front wheels and one or more rear wheels.

(5) The drive system that applies torque to the left drive wheel and the right drive wheel may have various configurations. For example, like the drive motors 51L and 51R in FIG. 4, the drive system has a left drive device configured to drive the left drive wheel and a right drive device configured to drive the right drive wheel. And may be provided. Alternatively, the drive system may include one drive device and a drive force distribution device that distributes the drive force of the drive device to the left drive wheel and the right drive wheel. Then, the control device 100 may adjust the distribution ratio of the driving force (that is, the torque of the left driving wheel and the torque of the right driving wheel) by controlling the driving force distribution device.

(6) The configuration of the turning wheel support device that supports the turning wheel such that the traveling direction of the turning wheel is turnable in the width direction of the vehicle body, instead of the configuration of the front wheel support device 41 described in FIG. Other various configurations may be possible. For example, the support member that rotatably supports the rotating wheel may be a cantilever member instead of the front fork 17. Further, the rotating device that supports the support member so as to be rotatable in the width direction with respect to the vehicle body may be various other devices instead of the bearing 68. For example, the turning device may be a link mechanism that connects the vehicle body and the support member.

Generally, it is preferable that the turning wheel support device fixed to the vehicle body supports the turning wheel so that the traveling direction of the turning wheel can be turned in the width direction of the vehicle body. According to this structure, the rotation axis of the rotation wheel (for example, the rotation axis Ax1 (FIG. 1)) is inclined with the vehicle body. Therefore, as described with reference to FIGS. 9A, 9B, 10 and the like, the traveling direction of the rotating wheel (for example, the direction D12 (FIG. 2)) follows the change in the inclination angle T of the vehicle body. Can change. Here, the rotating wheel support device may include K (K is an integer of 1 or more) support members. Each support member may rotatably support one or more rotating wheels. The turning wheel support device may include K turning devices fixed to the vehicle body. The K rotating devices may respectively support the K supporting members so as to be rotatable in the width direction.

(7) The configuration of the steering drive device that generates the turning torque for turning the traveling direction of the turning wheel in the width direction is not limited to the configuration of the steering motor 65 described in FIG. You can For example, the steering drive device may include a pump, and the hydraulic pressure (eg, hydraulic pressure) from the pump may be used to generate the turning torque. Here, the steering drive device may be configured to apply a turning torque to each of the K support members. For example, a steering drive may be coupled to each of the K support members.

(8) The structure of the tilting device for tilting the vehicle body in the width direction may be various other structures instead of the structure of the link mechanism 30 described with reference to FIG. For example, the link mechanism 30 may be replaced with a base. The drive motors 51L and 51R are fixed to the table. The first support portion 82 is rotatably connected to the base by a bearing. The lean motor 25 rotates the first support portion 82 in the width direction with respect to the base. As a result, the vehicle body 90 can be inclined to the right side DR and the left side DL, respectively. The first support portion 82 may be rotatable with respect to the base about a rotation axis of the bearing within a predetermined angular range (for example, a range of less than 180 degrees). For example, the angular range may be limited by contacting a specific portion of the first support portion 82 with a specific portion of the table. Further, the left slide device may connect the left rear wheel 12L and the vehicle body, and the right slide device may connect the right rear wheel 12R and the vehicle body. Each slide device can change the relative position of the vehicle body upward direction DVU with respect to the vehicle body. The tilting device may include two such sliding devices (eg hydraulic cylinders).

In general, the tilting device is referred to as "a first wheel that is directly or indirectly connected to at least one of a pair of wheels (for example, a left drive wheel and a right drive wheel) arranged apart from each other in the width direction of the vehicle body. The “member”, the “second member directly or indirectly connected to the vehicle body”, and the “connecting device for movably connecting the first member to the second member” may be included. In the embodiment of FIG. 4, the upper horizontal link member 31U is an example of a first member connected to the wheels 12L and 12R via the vertical link members 33L and 33R and the motors 51L and 51R. The middle-longitudinal link member 21 is an example of a second member connected to the vehicle body 90 via the first support portion 82 and the suspension system 70. The bearing 39 is an example of a connecting device that movably connects the first member to the second member.

(9) The tilt drive device that drives the tilt device first applies a force that changes the relative positions of the first member and the second member (for example, torque that changes the orientation of the second member with respect to the first member). It may be various devices that apply to the member and the second member. The tilt drive may include an electric motor, such as lean motor 25. Also, if the tilting device includes a hydraulic cylinder, the drive device may include a pump.

(10) The operation input unit is operated to input an operation amount indicating the turning direction and the degree of turning, instead of a device that can rotate left and right like the handle 41a (FIG. 1). It may be other various devices configured as described above. For example, the operation input unit may include a lever that can be tilted leftward and rightward from a predetermined reference direction (for example, an upright direction).

(11) The configuration of the control device 100 is configured to control the drive system (for example, the drive system 51S), the steering drive device (for example, the steering motor 65), and the tilt drive device (for example, the lean motor 25). There may be various configurations. For example, the control device 100 may be configured using one computer. At least a part of the control device 100 may be configured by dedicated hardware such as an ASIC (Application Specific Integrated Circuit). For example, the drive device controller 300, the lean motor controller 400, and the steering motor controller 500 of FIG. 11 may be configured by ASIC. The control device 100 may be various electric circuits, for example, an electric circuit including a computer or an electric circuit not including a computer. Further, the input value and the output value associated with the map data (for example, the inclination angle map data MT) may be associated with other elements. For example, an element such as a mathematical function or an analog electric circuit may associate the input value with the output value.

Further, as the tilt angle used for controlling the tilt drive device or the like, instead of the tilt angle T (FIG. 5B) based on the vertically upward direction DU, the degree of tilt of the vehicle body 90 in the width direction is shown. Various angles may be employed. For example, the control angle Tc may be used as the tilt angle. In this case, the vehicle 10 is preferably provided with a sensor configured to measure the control angle Tc. This sensor is an example of a tilt angle sensor.

(12) The configuration of the vehicle may be various other configurations instead of the configurations of the above-described embodiment and modified examples. For example, in the embodiment of FIG. 4, the motors 51L and 51R may be connected to the link mechanism 30 via a suspension. The drive device that drives the drive wheels may be any device that generates torque that rotates the wheels instead of the electric motor (for example, an internal combustion engine). The maximum number of passengers for the vehicle may be two or more instead of one. The correspondence relationship (for example, the correspondence relationship indicated by the map data MT, MAF, MTQ, MKpa, MKb, Mp1, Mp2) used for controlling the vehicle may be experimentally determined so that the vehicle can travel appropriately. .. The vehicle control device may dynamically change the correspondence relationship used to control the vehicle in accordance with the state of the vehicle. For example, the vehicle may include a weight sensor that measures the weight of the vehicle body, and the control device may adjust the correspondence according to the weight of the vehicle body.

In each of the above embodiments, part of the configuration realized by hardware may be replaced with software, and conversely, part or all of the configuration realized by software may be replaced with hardware. Good. For example, the function of the control device 100 of FIG. 11 may be realized by a dedicated hardware circuit.

When some or all of the functions of the present invention are realized by a computer program, the program is provided in a form stored in a computer-readable recording medium (for example, a non-transitory recording medium). be able to. The program can be used while being stored in the same recording medium (computer-readable recording medium) as that provided or provided. The “computer-readable recording medium” is not limited to a portable recording medium such as a memory card or a CD-ROM, but is connected to an internal storage device in the computer such as various ROMs or a computer such as a hard disk drive. External storage may also be included.

Although the present invention has been described above based on the examples and modifications, the above-described embodiments of the invention are for the purpose of facilitating the understanding of the present invention and do not limit the present invention. The present invention can be modified and improved without departing from the spirit thereof, and the present invention includes equivalents thereof.

The present invention can be suitably used for vehicles.

10... Vehicle, 11... Seat, 12F... Front wheel, 12L... Left rear wheel (driving wheel), 12R... Right rear wheel (driving wheel), 12Fc... Center of gravity, 12La, 12Ra... Wheel, 12Lb, 12Rb... Tire, 17... Front fork, 20... Main body portion, 20a... Front wall portion, 20b... Bottom portion, 20c... Rear wall portion, 20d... Support portion, 21... Middle vertical link member, 25... Lean motor, 30... Tilt device (link mechanism), 31D... Lower horizontal link member, 31U... Upper horizontal link member, 33L... Left vertical link member, 33R... Right vertical link member, 38, 39... Bearing, 41... Front wheel support device, 41a... Handle, 41ax... Support rod, 45 ... accelerator pedal, 46... brake pedal, 47... shift switch, 51L... left drive motor, 51R... right drive motor, 51S... drive system, 65... steering motor, 68... bearing, 70... suspension system, 70L... left suspension, 70R... right suspension, 71L, 71R... coil spring, 72L, 72R... shock absorber, 75... connecting rod, 80... rear wheel support part, 82... first support part, 83... second support part, 90... vehicle body, 90c Center of gravity, 100... Control device, 110... Main control unit, 300... Drive device control unit, 400... Lean motor control unit, 500... Steering motor control unit, 110g, 300g, 400g, 500g... Program, 110n, 300n, 400n , 500n... Nonvolatile storage device, 110p, 300p, 400p, 500p... Processor, 110v, 300v, 400v, 500v... Volatile storage device, 300c, 400c, 500c... Power control unit, 120... Battery, 122... Vehicle speed sensor, 123... Steering wheel angle sensor, 124... Wheel angle sensor, 126... Vertical direction sensor, 126a... Acceleration sensor, 126c... Control part, 126g... Gyro sensor, 127... Inclination angle sensor, 145... Accelerator pedal sensor, 146... Brake pedal sensor , DF... frontward, DB... rearward, DU... vertical upward, DD... vertical downward, DL... leftward, DR... rightward

Claims (2)

1. A vehicle,
   The car body,
   N (N is an integer of 3 or more) wheels including one or more turning wheels supported by the vehicle body, the left driving wheel and the right driving wheel being spaced apart from each other in the width direction of the vehicle body. The N wheels, wherein the traveling direction of the one or more rotating wheels is rotatable in the width direction of the vehicle body,
   A drive system configured to apply torque to the left drive wheel and the right drive wheel;
   A steering drive device configured to generate a torque for rotating the one or more rotating wheels in the width direction;
   A tilting device configured to tilt the vehicle body in the width direction,
   A tilting drive configured to drive the tilting device,
   A vehicle speed sensor configured to measure the vehicle speed of the vehicle,
   A wheel angle sensor configured to measure a wheel angle indicating the traveling direction of the one or more rotating wheels with respect to the vehicle body;
   An operation input unit configured to be operated to input an operation amount indicating a turning direction and a degree of turning,
   A control device configured to control the drive system, the steering drive device, and the tilt drive device;
   Equipped with
   The control device is
   The target wheel angle is specified using the operation amount and the vehicle speed,
   When the operation amount indicates a turn, the tilt drive device tilts the vehicle body inward of the turn,
   When the vehicle speed is less than a first threshold value and a first condition including that the state of the steering drive device is not a predetermined malfunction state is satisfied, the wheel angle approaches the target wheel angle. Controlling the torque produced by the steering drive,
   When the vehicle speed is less than the first threshold value and the second condition including the state of the steering drive device is in the defective state is satisfied, the wheel angle approaches the target wheel angle, Controlling the difference between the left torque, which is the torque of the left drive wheel, and the right torque, which is the torque of the right drive wheel, applied by a drive system;
   vehicle.
2. The vehicle according to claim 1, wherein
   When the ratio of the magnitude of the difference between the left torque and the right torque with respect to the magnitude of the difference between the wheel angle and the target wheel angle is called a torque angle proportion,
   When the second condition is satisfied, the control device compares the torque angle ratio when the vehicle speed is faster than a second threshold value with the torque angle ratio when the vehicle speed is slower than the second threshold value. Controlling the difference between the left torque and the right torque to be smaller,
   vehicle.

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