JP2009040124A - Wheel position variable vehicle and wheel position control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel position variable vehicle and a wheel position control method capable of realizing both an improvement in maneuvering stability and an improvement in convenience. <P>SOLUTION: This wheel position variable vehicle has a tread & wheel base changing actuator 350 for moving respective wheel units 300 to an optional position in the vehicle width direction to a vehicle body 100, a wheel load control device 510 commanding a change in a wheel position to the tread & wheel base changing actuator 350 so that a wheel load of respective wheels 390 becomes a target wheel load, and a cabin position control device 520 commanding the change in the wheel position to the tread & wheel base changing actuator 350 so that a position in the vehicle width direction of the vehicle body becomes a target vehicle body position, by making a distance between one of right-left wheels and a central position in the vehicle width direction of the vehicle body and a distance between the other of the right-left wheels and the central position in the vehicle width direction different. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention belongs to the technical field of a wheel position variable vehicle and a wheel position control method capable of changing a wheel position with respect to a vehicle body.

Patent Document 1 discloses a vehicle that can independently change the tread bases of the front wheels and the rear wheels in accordance with the traveling state of the vehicle in order to achieve both reduction in parking space and improvement in driving stability. (For example, refer to Patent Document 1).
JP 2006-264510 A

  However, in the above prior art, since the center position in the vehicle width direction of the vehicle body according to the tread base change always coincides, there is room for further improvement with respect to ensuring the steering stability of the vehicle. In addition, since the means for changing the wheel position is used only for reducing the parking space and ensuring steering stability, there is room for further improvement in terms of convenience as a vehicle.

  The present invention has been made paying attention to the above-described problems, and an object of the present invention is to provide a wheel position variable vehicle and a wheel position control method capable of realizing both improvement in steering stability and improvement in convenience. It is to provide.

  In order to achieve the above object, in the present invention, the wheel position changing means for moving each suspension means to an arbitrary position in the vehicle width direction with respect to the vehicle body, and the wheel so that the wheel load of each wheel becomes the target wheel load. First wheel position control means for instructing the position changing means to change the wheel position; a distance between one of the left and right wheels and the vehicle width direction center position of the vehicle body; and a distance between the other of the left and right wheels and the vehicle width direction center position. And a second wheel position control means for commanding the wheel position changing means to change the wheel position so that the vehicle width direction position of the vehicle body becomes the target vehicle body position.

In the present invention, since the wheel load can be changed according to the target value, the steering stability can be improved. Further, since the vehicle width direction position of the vehicle body can be changed according to the target vehicle body position, it is possible to improve convenience.
As a result, it is possible to achieve both improved steering stability and improved convenience.

  Hereinafter, the best mode for carrying out the present invention will be described based on Examples 1 to 4 shown in the drawings.

[overall structure]
FIG. 1 is an external view of a wheel position variable vehicle according to a first embodiment, and four wheel units (suspension means) 300 are arranged at a lower portion of a vehicle body 100.

  FIG. 2 is a plan view showing a system configuration of the wheel position variable vehicle of the first embodiment. FIG. 3 is a control block diagram of the wheel position variable vehicle of the first embodiment. , Steering angle sensor (steering angle detection means) 110, accelerator opening sensor 111, acceleration & yaw rate sensor (lateral acceleration detection means, yaw rate detection means) 120, pitch & roll angle sensor 130, vehicle speed sensor ( Vehicle speed detection means) 140, four wheel units 300, a vehicle behavior control device 400, and a geometry control device 500.

  The steering angle sensor 110 detects the steering wheel operation amount (steering angle) of the driver. The accelerator opening sensor 111 detects the accelerator pedal operation amount of the driver. The acceleration & yaw rate sensor 120 detects vehicle acceleration and yaw rate, respectively. Pitch & roll angle sensor 130 detects the pitch angle and roll angle of the vehicle body. The vehicle speed sensor 140 detects the vehicle speed (vehicle speed). The turning angle sensor 320 detects the turning angle of the wheel 390 (the wheel turning angle with respect to the front of the vehicle).

  Each wheel unit 300 includes a wheel unit position sensor 310, a wheel rotation speed sensor 315, a turning angle sensor 320, a driving actuator (driving means) 330, a turning actuator (steering means) 340, a tread & wheel base change actuator (wheel). Position changing means) 350 and wheels 390.

  The wheel unit position sensor 310 detects the position of the wheel 390 (wheel unit 300) with respect to the vehicle body 100. Wheel rotation speed sensor 315 detects the rotation speed of wheel 390. The turning angle sensor 320 detects the turning angle of the wheel 390 (the angle formed by the wheel with respect to the vehicle longitudinal direction).

  The drive actuator 330 applies a drive torque to the wheel 390. As the drive actuator 330, for example, an in-wheel motor can be used. The turning actuator 340 changes the turning angle of the wheel 390. As the steering actuator 340, for example, an electric motor can be used. The drive actuator 330 and the steering actuator 340 are controlled by the vehicle behavior control device 400 and the geometry control device 500.

The tread & wheelbase changing actuator 350 moves each wheel unit 300 along the wheel unit moving track 200. The tread and wheelbase changing actuator 350 is controlled by the geometry control device 500. Here, the wheel unit moving track 200 is set in a horizontal circle centered on the center of gravity of the vehicle body, and each wheel 390 moves on one annular track centered on the center of gravity of the vehicle body.
The vehicle behavior control device 400 drives the drive actuator 330 and the steering actuator 340 in accordance with signals from each sensor, and controls the vehicle body speed and the traveling direction of the vehicle.

The geometry control device 500 includes a wheel load control device (first wheel position control means) 510 and a cabin position control device (second wheel position control means) 520.
The wheel load control means 510 controls the wheel load movement control to instruct the tread & wheel base change actuator 350 to change the wheel position so that the wheel load of each wheel 390 becomes the target wheel load according to the signal from each sensor. Execute.

  The cabin position control device 520 determines the distance between one of the left and right wheels and the center position in the vehicle width direction of the vehicle body 100, the other of the left and right wheels and the vehicle width direction in response to a signal from each sensor or a cabin position change command from the driver. By changing the distance from the center position, cabin position movement control is performed to command the tread & wheelbase change actuator 350 to change the wheel position so that the vehicle width direction position of the cabin (vehicle body) becomes the target vehicle body position. Execute. In this cabin position movement control, an output of drive torque is commanded to the drive actuator 330 and a change of the turning angle (toe angle) is commanded to the steering actuator 340 depending on the situation.

  The geometry control device 500 determines which of the wheel load movement control and the cabin position movement control is prioritized to change the wheel position according to the acceleration of the vehicle. The cabin position control device 520 always calculates the wheel position according to the cabin position movement when the driver requests the cabin position movement, but the geometry control device 500 has an acceleration exceeding a predetermined acceleration threshold value. During sudden acceleration, wheel load movement control is executed from the viewpoint of vehicle behavior stabilization. When the acceleration is equal to or less than the acceleration threshold value, cabin position movement control is executed in consideration of convenience. Accordingly, convenience can be provided in a scene where the influence on the vehicle behavior due to the movement of the wheel load is small, and movement of the wheel load can be limited in a scene where the influence on the vehicle behavior due to the movement of the wheel load is large.

[Wheel mounting structure]
FIG. 4 is a side view showing a wheel mounting structure in the wheel position variable vehicle of the first embodiment.
The wheels 390 are connected to the vehicle body 100 via the suspension frame 600. The suspension frame 600 is attached to the vehicle body 100 by a bearing 610 provided on the bottom surface of the vehicle body 100 (or the bottom surface of another suspension frame) and a linear motor slider 615 provided in an annular shape along the center of the side surface of the vehicle body 100. It is supported so as to be relatively rotatable. The linear motor slider 615 according to the first embodiment corresponds to the tread & wheel base changing actuator 350 shown in FIG. 2, and moves the wheel 390 relative to the vehicle body 100 by the thrust in the horizontal direction of the linear motor.

  The rod 620 that supports the steered shaft of the wheel 390 has a central portion supported by the suspension frame 600 via the bearing 630 and an upper end portion supported by the suspension arm 650 via the ball joint 640. The suspension arm 650 is provided so as to be rotatable in the vertical direction with respect to the suspension frame 600.

  A steering gear 660 is connected to the rod 620, and the wheel 390 is steered by driving a steered actuator 340 fixed to the suspension frame 600.

[Effect of wheelbase change by wheel position movement]
FIG. 5 shows a change state of the wheel base due to the movement of the wheel 390. By moving the wheel unit 300 using the tread & wheelbase changing actuator 350 shown in FIG. 2, the wheel base variable vehicle of the first embodiment can expand or contract the wheelbase.

  In the wheel position variable vehicle of the first embodiment, for example, in an extremely low speed running such as an urban running at a relatively low speed or in a garage, the turning radius can be reduced by reducing the wheel base (FIG. 5A). ). In medium / high speed driving and winding driving, driving stability can be obtained by expanding the wheel base (FIGS. 5B and 5C). These operations may be automatically selected according to the vehicle speed or the like, or may be selected by a driver's operation.

[Wheel load movement control]
Next, wheel load movement control by the wheel load control device 510 according to the first embodiment will be described.
The wheel load movement control of the first embodiment is mainly used in normal traveling excluding the above-described urban traveling and garage entry. In other words, in the vehicle according to the first embodiment, in a scene where traveling stability is required, not only the tread and the wheel base are enlarged, but also the wheel load movement control is performed, thereby improving the traveling stability. It is intended to be illustrated.

  If there is no movement of the wheel load accompanying the turning, the cornering power does not decrease and the turning performance does not deteriorate, so that the vehicle behavior can be stabilized. Even when it is not necessary to increase the maximum value of the cornering power, it is possible to select a tire with a high flatness ratio, so that an improvement in fuel consumption can be expected.

  In other words, if the wheel load of each wheel can be evenly distributed during turning, the wheel load will not move, the tire lateral force of each wheel 390 can be used evenly, and the cornering power will not decrease. The vehicle behavior can be stabilized.

Although only the influence on the cornering power has been described, the same tendency can be seen even if the cornering power is replaced with acceleration in the vehicle longitudinal direction. That is, when the wheel load moves due to acceleration / deceleration, the tire friction force on the side where the wheel load has increased reaches the limit, and the braking force and acceleration force are limited. On the other hand, although the tire on the side where the wheel load is reduced has a margin in the tire friction force, the tire friction force cannot be transmitted to the road surface because the wheel load is reduced.
Therefore, if the wheel load can be evenly distributed during deceleration and acceleration, the vehicle behavior can be stabilized.

  Next, FIG. 6 shows a tread base and a wheel base when the wheel loads of four wheels are equally distributed. In Example 1, each wheel position is changed so that the wheel loads of the four wheels are equal. FIG. 6 shows the relationship between the wheel position and the vehicle center of gravity when the vehicle is viewed from above, and the relationship between the wheel position and the vehicle center of gravity when the vehicle is viewed from the side perpendicular to the acceleration direction. ing.

In FIG. 6, when a combined acceleration (yaw rate, centrifugal force for turning, longitudinal acceleration for acceleration / deceleration, or both) is generated by turning, acceleration / deceleration, etc. of wheels 390, it acts on the center of gravity G of the vehicle. The acceleration in the planar direction is expressed as a combined acceleration G _{(x, y)} . Further, the direction in which the resultant acceleration G _{(x, y)} is generated is set as the resultant acceleration direction axis.
Then, an axis that is orthogonal in the plane direction at the vehicle center of gravity position G is set as a composite acceleration direction orthogonal axis.

  Here, the resultant acceleration vector is obtained by the acceleration & yaw rate sensor 120 attached to the vehicle body, and the X direction and the Y direction are determined based on the attachment position and direction of the sensor with respect to the vehicle body. The direction is the X direction and the horizontal direction is the Y direction.

Next, the acceleration rearward axis as the resultant acceleration direction perpendicular each virtual axle shaft obtained by l ₁ parallel moved in the opposite direction and l ₂ and the resultant acceleration vector directions for synthesis acceleration vector direction axis, and acceleration forward axis.

Further, if the vertical acceleration (mainly gravitational acceleration) acting on the vehicle center of gravity G is a vector G _(z) and the height of the vehicle center of gravity from the road surface is h, the acceleration rear axis and acceleration described above are used. The acceleration rear axle wheel load W ₂ and the acceleration front axle wheel load W ₁ acting on the front shaft are expressed by the following equation (1).

here,
G _{(x, y)} = {(G _(x) + ΔG _(x) ) ² + (G _(y) + ΔG _(y) ) ² } ^1/2 : Composite acceleration
G _(i) : Detected from acceleration & yaw rate sensor ΔG _(i) : Posture correction acceleration calculated from target vehicle posture m: Vehicle mass h: Center of gravity height
G _(z) : Gravitational acceleration.

According to the equation (1), in order to suppress the wheel load movement and stabilize the vehicle behavior, the wheel load W _{2 on} the acceleration rear axis and the wheel load W _{1 on the} acceleration front shaft need only be equalized. In 1), W ₁ ≈W ₂ should be satisfied. As is clear from equation (1), if l ₁ and l ₂ are infinite, W ₁ ≈W ₂ regardless of the magnitude of G _{(x, y)} . This indicates that the wider the distance between the wheels (front and rear wheels, left and right wheels), the smaller the wheel load movement due to the resultant acceleration and the more stable the vehicle behavior. Equivalent to long wheelbase.

  Conventionally proposed wheel position variable vehicles have a wide tread base and long wheels at high speeds (high speeds and windings) that can generate large accelerations in order to achieve both compactness and stable vehicle behavior. The base is stabilized to stabilize the vehicle behavior, and at the time of low speed driving (for example, urban driving) where large acceleration cannot be generated, a narrow tread base and a short wheel base are used to improve compactness and small turning ability.

ここで、
G_rate=G_(x,y)/G_z：加速度比
l_rate=l₁/l₂：ジオメトリ比
h_rate=h/l₂：高さ比
である。 However, in view of the direction of the combined acceleration, it can be seen that the movement of the wheel load can be suppressed even if it is not necessarily a wide tread base or a long wheel base.
That is, in order to equalize the wheel loads of the four wheels, W ₁ = W ₂ , that is, l ₁ and l ₂ may be set so as to satisfy the following expression (2).

here,
G _rate = G _{(x, y)} / G _z : Acceleration ratio
l _rate = l ₁ / l ₂ : Geometry ratio
h _rate = h / l ₂ : Height ratio.

According to Equation (2), when the resultant acceleration G _{(x, y)} occurs in a certain direction, the two virtual axle positions for equally distributing the wheel loads of the four wheels are obtained. By arranging the four wheels so as to realize, the wheel load distribution of the four wheels becomes equal.

In addition, although the wheel load to the left and right wheels with respect to the virtual main shaft is generated by W ₁ and W ₂ , if the movement locus is made into a perfect circle as in the first embodiment, the wheel is simply arranged on the virtual axis line, Since both wheels are always equidistant from the load point with respect to the virtual axle, it is possible to omit calculation of wheel load distribution to the left and right wheels with respect to the virtual axle.

FIG. 7 shows the movable range of l ₁ and l ₂ when the axle loads of W ₁ and W ₂ are evenly distributed.
In FIG. 7, since the movable range of l ₁ and l ₂ when the center of gravity height h is 0.5 [m] is calculated, the combination of l ₁ and l ₂ that equalizes the axle load with respect to the plane acceleration [G] Is plotted as a wheel load uniform surface α.

Based on Fig. 7, considering that the wheel load of four wheels is equally distributed with the minimum distance between the axes, the general vehicle acceleration G _rate is the maximum value, 1.1 [G] (friction coefficient of about 1.0, special Even if there is no downforce), the movable range of l ₁ and l ₂ in which the wheel load can be evenly distributed is searched from the characteristic diagram of the cornering power with respect to the wheel load shown in FIG.

As shown by the straight line min in FIG. 7, when l ₁ = 0, l ₂ = 1.1 [m], the wheel load is evenly distributed at the point E to l ₁ and l ₂ with the minimum movable range and the maximum acceleration. be able to. In other words, if the vehicle can vary l ₁ between 0 and 1.1 [m] and l ₂ between 0 and 1.1 [m], the wheel load can be evenly distributed regardless of the G _rate of 1.1 [G]. .

As described above, in the vehicle in which l ₁ can be varied between 0 and 1.1 [m] and l ₂ between 0 and 1.1 [m], the wheel load equal distribution control will be further described with reference to FIG.
For example, assume that the initial position l _{1 of the} wheel is 0.8 [m] and l ₂ is 0.8 [m]. This is point A in FIG. When the vehicle travels without acceleration, deceleration, or turning, the vehicle is positioned on the uniform distribution plane E because of acceleration 0 [G].

Next, when the turning acceleration is 0.2 [G], the position of the wheel is changed so that it becomes point B. If there is no intersection on the uniform distribution plane in FIG. 7, the uniform distribution of the wheel load distribution cannot be realized, and therefore l ₁ and l ₂ satisfying the uniform distribution of the wheel load when the acceleration is 0.2 [G] are searched.

At this time, in the first embodiment, the wheel positions are searched such that the movement amount of each wheel is equal. That is, the point B is Δl ₁ = −0.1, Δl ₂ = + 0.1, the point B ′ is Δl ₁ = −0.2, Δl ₂ = 0, and the total movement amount is the same. This is the total travel distance of the tread and wheelbase change actuator 350, whereas in the case of point B, the total travel distance of the four tread and wheelbase change actuator 350 is the total travel distance of the four actuators. The movement to point B can be completed faster if the speeds of are the same. In this way, the robot moves to point D according to the increase in acceleration. And when acceleration further increases, it moves toward the point F.

Note that, from point D to point F, only l ₁ changes and equalization is not achieved, but in consideration of the frequency of acceleration of 0.6 [G] or more, for example, the wheel position indicated by the dotted line is selected. May be.

  As described above, the equal distribution of the wheel load can be realized with a short distance between the axles, and the decrease in cornering power can be suppressed by performing the equal distribution of the wheel load. That is, even a compact vehicle can improve vehicle behavior such as turning behavior while maintaining a compact vehicle geometry by moving the tire unit.

[Cabin position movement control]
Next, cabin position movement control by the cabin position control device 520 of the first embodiment will be described.

First, the operation principle of the cabin position movement control will be described with reference to FIG.
In FIG. 9, the operation of the wheels when moving only the vehicle body 100 in the right direction without moving the entire vehicle including the wheels 390 in the right direction will be considered.

First, considering the operation of the left wheel 390 (left front wheel) in FIG. 9, the tread & wheel base changing actuator 350 increases the angle θ _a formed by the wheel 390 with respect to the traveling direction of the vehicle, that is, counterclockwise. When a force is applied in the direction of rotation, a force F is applied in the tangential direction of the movement locus of the wheel unit 300 (the wheel unit movement track 200 in FIG. 2) at that time. This force F is divided into a lateral force F _lat and a longitudinal force F _lon of the wheel 390 depending on the direction in which the wheel 390 faces. Then, the lateral force _Flat is applied to the vehicle body 100 as a reaction force of the frictional force. Further, a part F _lon tanθ _{a of} the longitudinal force F _lon is also applied to the vehicle body 100 through the wheel reaction force.

  Similarly, by applying a force in the counterclockwise direction to the wheel unit 300 on the right wheel 390 (right front wheel) in FIG. 9, a force for moving the vehicle body 100 in the right direction can be obtained by the same action. Although illustration is omitted, the same operation can be obtained for the remaining two wheels (rear wheels) by applying a force in the clockwise direction to the wheel unit 300.

  Therefore, when there is an instruction to move the vehicle body in the lateral direction from the driver's operation or the like, the entire vehicle is moved in the lateral direction by applying force to each wheel unit 300 by the tread & wheel base changing actuator 350. Without moving, only the vehicle body 100 can be moved in the lateral direction. In other words, by bringing the vehicle body 100 to the target, such as a toll road ticketing machine or receiving goods, the vehicle body (driver) can move the target without requiring advanced driving skills such as bringing the entire vehicle to the target. In addition, as will be described later, it is possible to realize passing on a narrow road, improving visibility at a corner, and the like.

  Here, in the first embodiment, each wheel unit 300 is moved on one annular track (wheel unit moving track 200). However, as shown in FIG. 10, the wheel base of the wheel and the wheel swivel of the tread base are used. The centers do not necessarily need to be coincident with the four wheels, and each wheel 390 may have a separate turning center.

Next, a method for maintaining the tread base (distance between the left and right wheels) constant when changing each wheel position and a method for positively changing the tread base will be described.
11 and 12, the wheel unit 300 sets the xy coordinates as shown in the figure with the vehicle body center of gravity GOG as the origin. Further, regarding the angle of the leg (suspension frame 600), the x-coordinate of the xy coordinate is zero, the counterclockwise direction is +, and the opposite direction is-. Further, the turning angle of the wheel 390 is set to + in the counterclockwise direction and − in the opposite direction, with the circumferential direction being zero from the rotation center of the leg.

FIG. 11 shows the state of the vehicle when the tread base is constant. Now, while the initial position can be expressed by the following equation (3), the target position when the vehicle body 100 is to be moved sideways by ytar can be expressed by the following equation (4).

  When changing the position of each wheel while keeping the tread base constant, the wheel moves with the four wheels at an angle close to 90 degrees with respect to the direction of movement of the vehicle body 100, so the lateral force of the four wheels is maximized. The vehicle body 100 can be moved efficiently.

On the other hand, FIG. 12 shows a state in which the tread base is not constant, and particularly shows a state where the wheel unit 300 located in the direction opposite to the vehicle body movement direction is fixed to the vehicle body 100. In this case, the target position is It can be expressed by (5).

  When the wheel 390 on the side opposite to the vehicle body moving direction is fixed to the vehicle body 100 and the position of each wheel is changed while changing the tread base, the wheels 390 protruding outward can be moved together when the vehicle body 100 is moved. Therefore, the outer wheel 390 does not get in the way when passing (separating) with the oncoming vehicle, and the passing (separating) can be facilitated.

Next, a method for limiting the movement amount of the vehicle body 100 will be described.
First, in FIG. 13A, for example, two proximity sensors (obstacle detection means) 150 that recognize an obstacle in the lateral direction of the vehicle are provided, and the lateral obstacle recognized by these two proximity sensors 150 and the vehicle body 100 are provided. Is calculated, and the lateral movement operation is limited when a predetermined threshold value is reached. Thereby, contact with an obstacle can be avoided. In addition to the proximity sensor, a camera may be used as the obstacle detection means.

Subsequently, FIG. 13 (b) limits the distance between the wheel 390 and the center of gravity in the direction in which the vehicle body 100 is moved when the vehicle body 100 is moved in order to avoid vehicle rollover. The maximum limit is, for example, the following formula (6).
l _{t_lim} = h x g (y) / g (z) (6)
In addition, when the lateral acceleration is in the minus direction, it is predicted that the limit where the center of gravity exceeds the wheel 390 is calculated, but in order to limit this, a range not exceeding the wheel 390 may be used. Further, a margin may be provided to cope with a sudden acceleration change during lateral movement.

Next, the effect will be described.
The wheel position variable vehicle according to the first embodiment has the following effects.

  (1) Four wheel units 300 that suspend the wheels 390, a steering actuator 340 that is provided in each wheel unit 300 and changes the direction of the wheels 390 with respect to the vehicle body 100, and a wheel 390 that is provided in each wheel unit 300 is driven. The drive actuator 330, the tread & wheel base change actuator 350 that moves each wheel unit 300 to an arbitrary position in the vehicle width direction with respect to the vehicle body 100, and the tread & wheel so that the wheel load of each wheel 390 becomes the target wheel load. The wheel load control device 510 that commands the wheel base change actuator 350 to change the wheel position, the distance between one of the left and right wheels and the center position in the vehicle width direction of the vehicle body, the other of the left and right wheels and the center position in the vehicle width direction By changing the distance, the wheel position change command is issued to the tread & wheelbase change actuator 350 so that the vehicle width direction position of the vehicle body becomes the target vehicle body position. A cabin position control device 520. Thereby, since wheel load and a vehicle body position can be changed according to each target value, both improvement in handling stability and improvement in convenience can be realized.

  (2) Since the wheel load control device 510 changes the wheel position so that the wheel load of each wheel 390 becomes equal, the wheel load control device 510 suppresses the movement of the wheel load during turning and acceleration / deceleration, and the tire grip of each wheel 390 Force (lateral force, braking / driving force) can be used evenly, and vehicle behavior during turning and acceleration / deceleration can be stabilized.

  (3) The wheel load control device 510 changes the distance between the wheel 390 and the vehicle center of gravity in the acceleration direction on the basis of the direction of acceleration acting on the vehicle center of gravity, so that the control direction is one direction, facilitating control. Can be planned.

  (4) The tread & wheelbase changing actuator 350 moves each wheel 390 along a circular arc orbit to move each wheel 390 along the circular arc trajectory. Can be moved.

  (5) The tread and wheel base change actuator 350 changes the tread base and the wheel base while maintaining a certain relationship in order to move each wheel 390 on one annular track (wheel unit moving track 200). be able to.

  (6) Since the cabin position control means 520 changes the position of each wheel while keeping the tread base constant, the vehicle body 100 can be moved effectively using the lateral force of the four wheels to the maximum.

  (7) The cabin position control device 520 is designed to improve convenience, for example, by moving the wheels 390 that protrude outward when the vehicle body 100 is moved in order to change the position of each wheel while changing the tread base. Can do.

  (8) When the vehicle body 100 is moved, the cabin position control device 520 maintains a constant distance between the wheel unit 300 located on the opposite side of the movement direction and the vehicle body center, and the wheel unit 300 located in the movement direction. Reduce the distance to the center of the car. As a result, when the vehicle body 100 is moved, the wheels 390 protruding outward can be moved together, thereby facilitating passing and the like.

  (9) The proximity sensor 150 that detects an obstacle on the side of the vehicle is provided, and the cabin position control device 520 is configured so that the distance between the detected obstacle and the vehicle body 100 is equal to or less than a predetermined threshold value. Stop moving. Thereby, since contact with an obstacle can be avoided, safety can be improved.

  (10) The cabin position control device 520 limits the amount of movement of the vehicle body 100 so that the movement range of the vehicle center of gravity position is within the range in the vehicle width direction of each wheel unit 300, thereby preventing the vehicle from rolling over. Can improve safety.

  (11) The cabin position control device 520 determines the amount of movement of the vehicle body 100 so that when the lateral acceleration acts on the vehicle, the movement range of the vehicle gravity center position is within the range in the vehicle width direction of each wheel unit 300. Limit. Thereby, even when a lateral acceleration occurs during traveling, the vehicle can be prevented from overturning, and safety during turning can be improved.

  (12) In a wheel position variable vehicle equipped with a tread & wheelbase change actuator 350 that moves the wheel unit 300 to an arbitrary position in the vehicle width direction with respect to the vehicle body 100, the vehicle acceleration exceeds a predetermined acceleration threshold value. During sudden acceleration, wheel load movement control is performed to change the wheel position so that the wheel load of each wheel 390 becomes the target wheel load.When the vehicle acceleration is below the acceleration threshold, one of the left and right wheels is controlled. The vehicle width direction position of the vehicle body 100 becomes the target vehicle body position by making the distance between the vehicle width direction center position of the vehicle body 100 different from the distance between the other of the left and right wheels and the vehicle width direction center position of the vehicle body 100. Thus, the cabin position movement control for changing the wheel position is executed. Thereby, it is possible to achieve both improvement in handling stability and improvement in convenience according to acceleration.

The second embodiment is mainly cabin position movement control during traveling. In addition, since the whole structure of Example 2 is the same as that of Example 1, illustration and description are abbreviate | omitted.
First, suppression of a single flow of the vehicle by the cabin position control device 520 of the second embodiment will be described. 14 shows a state in which the vehicle width direction center position of the vehicle body 100 is close to the left and right wheels 390, that is, the distance between one of the left and right wheels and the vehicle width direction center position, the other of the left and right wheels and the vehicle width direction center. It is the analysis result which shows the relationship between a wheel slip angle and lateral force at the time of drive | working in the state which varied the distance with a position.

  From the analysis result of FIG. 14, when the vehicle travels straight with the center position in the vehicle width direction of the vehicle body 100 close to the left and right wheels 390, the slip angle is applied to the wheel with the larger wheel load due to the balance between the left and right lateral forces. It was found that a single flow of the vehicle occurred.

  For this reason, in the second embodiment, when the vehicle travels straight with the center position in the vehicle width direction of the vehicle body 100 close to the left and right wheels 390, the slip angle applied to the wheels 390 is canceled as shown in FIG. Thus, the toe angle control for turning the wheel 390 is performed. Alternatively, in place of the toe angle control, braking / driving force distribution control for generating a driving force difference or a braking force difference between the left and right wheels may be performed so as to cancel the generation of the yaw moment accompanying the provision of the wheel slip angle.

  When traveling straight with the vehicle width direction center position of the vehicle body 100 close to the left and right wheels 390, the wheel loads of the left and right wheels differ by performing the toe angle control or braking / driving force difference distribution control. Therefore, it is possible to suppress the one-way flow of the vehicle due to the fact, and it is possible to improve safety at the time of separation.

Next, a method for moving the vehicle body 100 by the cabin position control device 520 of the second embodiment will be described.
16A shows an image when the vehicle body 100 is moved by the driving force of the drive actuator 330, and FIG. 16B shows an image when the vehicle body 100 is moved by the driving force of the tread & wheelbase changing actuator 350.

  FIG. 17 shows the gain of each actuator due to the difference in angle formed by the wheel unit 300 with respect to the vehicle longitudinal direction. As shown in FIG. 18, using the tread & wheelbase change actuator (T & W ACT) 350 as a whole is more efficient than using the drive actuator (D ACT) 330. In a part where the angle is large, there is a place where the gain becomes larger when the drive actuator 330 is used.

  Therefore, in the second embodiment, the actuator used when moving the vehicle body 100 is changed according to the angle formed by the wheel unit 300 with respect to the vehicle longitudinal direction. That is, when the angle of the wheel unit 300 with respect to the vehicle longitudinal direction is equal to or smaller than the predetermined angle, the tread & wheel base changing actuator 350 is driven, and when the angle exceeds the predetermined angle, the drive actuator 330 is driven. Thereby, when the vehicle body 100 is moved, the energy consumption of the actuator can be suppressed.

  FIG. 18 shows an example of the left / right output balance of the actuator torque due to the difference in angle between the left and right wheel units 300. As shown in the result of FIG. 17, since the gain of the actuator varies depending on the position of the wheel unit 300, as shown in FIG. 18, when the same lateral force is applied to the vehicle body, it is necessary to control to balance the left and right actuators. is there.

  Therefore, in the second embodiment, the left and right actuator drive ratio (output ratio) is changed in accordance with the angle of the wheel unit 300 in order to suppress the unevenness of the left and right lateral force caused by the angle difference between the left and right wheel units 300. . Accordingly, the outputs of the left and right actuators can be balanced regardless of the positions of the left and right wheel units 300, and the energy consumption of the actuators can be suppressed.

  In the first embodiment, when the vehicle body 100 is moved, a method of moving the vehicle body 100 in a state where the wheel unit 300 located in the direction opposite to the vehicle body movement direction is fixed to the vehicle body 100 is shown. In this case, as shown in FIG. Thus, since it is necessary to apply the torque necessary for dragging the wheel 390 of the fixed wheel unit 300 to the wheel unit 300 on the driving side, it becomes very inefficient.

  Therefore, in the second embodiment, as shown in FIG. 21 (a), the vehicle body 100 is fixed according to the lateral speed v from the relationship between the transition of the moving distance y and the transition of the moving speed v (FIG. 20). The wheel slip angle β on the side is calculated, and toe angle control (steering) for canceling the calculated wheel slip angle β is performed. As a result, there is no dragging on the fixed-side wheel 390, and energy consumption can be reduced.

  Further, as shown in FIG. 21 (b), the resultant force of the force (drive force u + lateral force) required by the fixed-side wheel 390 is obtained, and the tread & wheel base is set so that the energy is minimized when generating this resultant force. By controlling the change actuator 350 and the drive actuator 350, a lateral force is obtained by the driving force u and the lateral force of the wheel 390, and the vehicle body 100 can be moved more efficiently.

Next, the effect will be described.
In the wheel position variable vehicle of the second embodiment, in addition to the effects of the first embodiment, the following effects can be obtained.

  (13) The cabin position control device 520 drives the driving force of the left and right wheels so as to cancel the yaw moment generated in the vehicle when traveling straight with the vehicle width direction center position of the vehicle body 100 close to the left and right wheels 390. Since the vehicle is distributed, it is possible to suppress the single flow of the vehicle and to improve the safety at the time of separation and the like.

  (14) The cabin position control device 520 allows the toe angle of each wheel 390 to cancel the generated wheel side slip angle when the vehicle 100 travels straight with the vehicle width direction center position close to the left and right wheels 390. Therefore, one-way flow of the vehicle can be suppressed, and safety at the time of separation and the like can be improved.

  (15) When the angle of the wheel unit 300 with respect to the vehicle longitudinal direction exceeds a predetermined angle, the cabin position control device 520 drives the drive actuator 330 instead of the tread & wheelbase change actuator 350, thereby Change the position of. Thereby, when the vehicle body 100 is moved, the energy consumption of the actuator can be suppressed.

  (16) The cabin position control device 520 changes the output ratio of the left and right tread & wheelbase change actuator 350 or the drive actuator 330 according to the angle of the wheel unit 300 with respect to the vehicle longitudinal direction. Thereby, the outputs of the left and right actuators can be balanced, and the energy consumption of the actuators can be suppressed.

  (17) When the vehicle body 100 is moved, the cabin position control device 520 fixes the position of the wheel unit 300 located on the side opposite to the moving direction with respect to the vehicle body 100, so that the wheel 390 that protrudes outward when the vehicle body 100 is moved. By moving the two together, the outer wheels 390 do not get in the way, and it is possible to facilitate passing (separation) and the like.

  (18) The cabin position control device 520 controls the toe angle of the wheel 390 so that the slip angle β of the fixed wheel 390 becomes zero. The energy consumption can be suppressed.

  (19) The cabin position control device 520 calculates the resultant force required by the fixed-side wheel 390, and sets the tread & wheelbase change actuator 350 and the drive actuator 330 so that the energy is minimized when generating this resultant force. Control. As a result, the lateral force of the wheel 390 on the fixed side can be used simultaneously with the movement of the vehicle body 100, so that energy consumption can be suppressed.

  The third embodiment is cabin position movement control during turning. In addition, although the whole structure of Example 3 is the same as that of Example 1, in Example 3, the structure shown in FIG. 10 with which each wheel unit has an individual turning center is employ | adopted.

  In the cabin position control device 520 according to the third embodiment, the vehicle is turned toward the vehicle body side while the vehicle is turning, and the vehicle body 100 is moved toward the outside of the vehicle to ensure a forward view of the curve. As shown in FIG. 22, the position of each wheel 390 is changed so that the position of the vehicle body 100 is more on the outside of the turn as the vehicle speed, the lateral acceleration of the vehicle, and the yaw rate of the vehicle are smaller. When the vehicle speed, the lateral acceleration of the vehicle, and the yaw rate of the vehicle are large, the position of the vehicle body 100 is determined as the straight travel position (the distance between one of the right wheels and the vehicle width direction center position of the vehicle body 100, and the left and right wheels). Of the vehicle body 100 in which the distance between the other of the two and the center position in the vehicle width direction coincides with each other) to stabilize the turning behavior.

  Also, as shown in FIG. 23, the position of each wheel 390 is changed so that the position of the vehicle body 100 is more on the outside of the turn as the steering angle is larger. When the steering angle exceeds a certain angle, the movement amount of the vehicle body 100 to the outside of the turn is reduced to stabilize the turning behavior.

  Furthermore, in the cabin position control device 520 of the third embodiment, the vehicle body 100 is moved forward (traveling direction) by moving each wheel 390 toward the vehicle rear side at the start of steering, and a forward view of the curve is ensured (see FIG. 24). Then, during the second half of the turn, the vehicle posture for straight running is adjusted early. As an order, after returning the position of the vehicle body 100 to the outside of the turn, each wheel 390 is returned to the position during straight traveling.

Next, the operation will be described.
For example, Japanese Patent Laid-Open No. 2006-264510 discloses a technique for improving the turning performance at low speeds by steering the rear wheels in the opposite phase to the front wheels. Since the position of the wheel unit 300 is constant, the effect of providing a suspension device independently for each of the four wheels is not obtained. In the four-wheel simultaneous steering, the rear moves slightly toward the outside of the turn at the initial stage of steering, but turns around the center of gravity, so that the front recognition is likely to be delayed and it is difficult to confirm the rear (FIG. 25).

  On the other hand, in the third embodiment, the vehicle body 100 is moved forward at the start of steering, so that the driver can recognize the front view of the curve at the early stage of turning earlier. Further, since the vehicle body 100 is moved out of the turn during the turn, the driver can recognize the front view of the curve during the turn earlier (FIG. 26). Further, by taking the vehicle body 100 outward from the turn, the rear bulges outward from the turn with respect to the above-described prior art, so that it is easy to confirm the rear (FIG. 27). In the third embodiment, since the vehicle posture is returned to the straight traveling posture from the second half of the turn, it is possible to prevent a single flow of the vehicle due to the deviation of the center of gravity of the vehicle from left to right when shifting from turning to straight running. The running stability can be ensured (FIG. 28).

  In the third embodiment, the amount of movement of the vehicle body 100 to the outside of the turn is adjusted according to the vehicle speed, the lateral acceleration of the vehicle, and the yaw rate of the vehicle. That is, when the lateral acceleration and yaw rate are low at low vehicle speeds, the roll angle during turning is small, and even if the vehicle body 100 is moved out of the turn, the turning behavior is not affected. To ensure forward visibility and backward confirmation. On the other hand, when the vehicle speed is high, the lateral acceleration and yaw rate are large, the roll angle becomes large, and the vehicle body 100 is likely to fall outside. The behavior can be stabilized (FIG. 29).

  In the third embodiment, the movement amount of the vehicle body 100 to the outside of the turn is adjusted according to the steering angle. That is, when the steering angle is small, the amount of turning of the vehicle is small, so there is no need to take the vehicle body 100 out of the turn. Since the turning amount increases as the steering angle increases, by increasing the amount of the vehicle body 100 to be turned outward, the front view of the curve during turning can be recognized more quickly, and the rear can be confirmed. However, if the steering angle exceeds a certain angle, the vehicle body 100 tends to fall outward, so that the turning behavior can be stabilized by reducing the amount of the vehicle body 100 to be turned outward (FIG. 30).

  In the third embodiment, the vehicle body 100 is moved forward at the beginning of turning (FIG. 31). That is, since it is necessary to confirm the forward position earlier at the initial stage of turning, the driver can recognize the forward view more quickly by taking the vehicle body 100 forward. On the other hand, since it is easier to check the front view if the vehicle body 100 is moved to the outside of the turn than the front during turning, returning the vehicle body 100 to the center position in the front-rear direction of the vehicle and moving it to the outside of the turn makes the front view faster Can be recognized by the driver.

Next, the effect will be described.
The wheel position variable vehicle according to the third embodiment has the following effects in addition to the effects of the first embodiment.

  (20) Since the cabin position control device 520 moves the vehicle body 100 to the outside of the turn at the time of turning, the front view of the curve can be secured earlier.

  (21) Since the cabin position control device 520 moves the position of the vehicle body 100 to the outside of the turn by bringing the wheels 390 closer to the inside in the vehicle width direction, the front view of the curve can be secured earlier.

  (22) The vehicle body speed sensor 140 that detects the vehicle speed is provided, and the cabin position control device 520 controls the amount of movement of each wheel 390 during turning according to the detected vehicle speed, so that the forward visibility is secured according to the vehicle speed. And stabilization of the turning behavior can be achieved.

  (23) A steering angle sensor 110 that detects the steering angle of the steering wheel is provided, and the cabin position control device 520 controls the amount of movement of each wheel 390 during a turn according to the detected steering angle. Accordingly, it is possible to achieve both of ensuring the forward view and stabilizing the turning behavior.

  (24) The vehicle is provided with an acceleration & yaw rate sensor 120 that detects the lateral acceleration of the vehicle, and the cabin position control device 520 controls the amount of movement of each wheel 390 during turning according to the detected lateral acceleration. It is possible to achieve both the securing of the forward field of view and the stabilization of the turning behavior according to the lateral acceleration.

  (25) The vehicle is provided with an acceleration & yaw rate sensor 120 that detects the yaw rate of the vehicle, and the cabin position control device 520 controls the amount of movement of each wheel 390 during the turn according to the detected yaw rate. Thus, it is possible to achieve both the securing of the forward view and the stabilization of the turning behavior.

  (26) Since the cabin position control device 520 moves the vehicle body 100 toward the front side of the vehicle at the initial stage of turning, the front view of the curve at the initial stage of steering can be secured earlier.

  The fourth embodiment is a cabin position movement control in a winding road where curves are continuous. Since the configuration is the same as that of the third embodiment, illustration and description thereof are omitted.

  In the cabin position control device 520 of the fourth embodiment, a winding road having a continuous curve is detected based on the vehicle speed, the brake operation of the driver, and information from the navigation system. By moving the vehicle body 100 to the vehicle body side and taking the vehicle body 100 out of the turn, the forward view is secured.

  Further, in the fourth embodiment, as shown in FIG. 32, in a low vehicle speed range where the detected vehicle speed is equal to or lower than the low vehicle speed threshold, the vehicle body 100 is moved outward as the vehicle speed decreases. As a result, the driver can recognize the front view of the curve more quickly. In the middle and high vehicle speed range where the vehicle speed exceeds the low vehicle speed threshold value, the vehicle body 100 is moved to the inside of the turn as the vehicle speed increases. Thereby, stabilization of the turning behavior in the high vehicle speed range can be achieved.

Next, the effect will be described.
The wheel position variable vehicle according to the fourth embodiment has the following effects in addition to the effects of the first and third embodiments.

  (27) The vehicle body speed sensor 140 that detects the vehicle speed is provided, and the cabin position control device 520 moves the vehicle body 100 to the outside of the turn in the low vehicle speed range where the detected vehicle speed is equal to or lower than the low vehicle speed threshold, and the vehicle speed is In the middle and high vehicle speed range exceeding the low vehicle speed threshold, the vehicle body 100 is moved inward of the turn. Thereby, it is possible to achieve both the securing of the forward visibility and the stabilization of the turning behavior according to the vehicle speed.

(Other examples)
As mentioned above, although the best form for implementing this invention was demonstrated by Example 1-4 based on drawing, the specific structure of this invention is not limited to what was shown in each Example. Any design changes that do not change the gist of the invention are also included in the present invention.

  For example, in the third and fourth embodiments, an example in which each wheel unit has a configuration with an individual turning center is shown. However, each wheel unit has the same configuration as that of the first embodiment in which the wheel unit moves on one annular track. Even if it is a case, the effect similar to Example 3, 4 can be acquired.

1 is an external view of a wheel position variable vehicle according to a first embodiment. It is a top view which shows the system configuration | structure of the wheel position variable vehicle of Example 1. FIG. It is a control block diagram of a wheel position variable vehicle of Example 1. It is a side view which shows the wheel attachment structure in the wheel position variable vehicle of Example 1. FIG. It is a figure which shows the change state of the wheel base by the movement of a wheel. It is a figure showing the tread base and wheel base in the case of equally distributing the wheel load of four wheels. Acceleration forward shaft wheel load W _1, a diagram illustrating a l _1, the movable range of l ₂ when the axle load of the acceleration rearward axis wheel load W ₂ evenly distributed. It is a characteristic view of cornering power with respect to wheel load. It is a figure which shows the principle of operation of the cabin position movement control of Example 1. FIG. FIG. 6 is a diagram illustrating a modified example of the first embodiment. It is a figure showing a wheel position change in case tread base is constant. It is a figure showing the wheel position change in the case of tread base variable. It is a figure which shows the vehicle body movement restriction | limiting method of Example 1. FIG. FIG. 6 is an analysis result showing a relationship between a wheel slip angle and a lateral force when the vehicle 100 travels in a state in which the center position in the vehicle width direction is close to the left and right wheels 390. FIG. It is a figure which shows the toe angle control which prevents the single flow of the vehicle of Example 1. FIG. 3 is a diagram illustrating a method for moving a vehicle body 100. FIG. FIG. 4 is a diagram illustrating gains of actuators according to a difference in angle formed by a wheel unit 300 with respect to a vehicle longitudinal direction. 7 is a drive ratio setting map for left and right actuators according to the second embodiment. It is a figure which shows the drag of the wheel at the time of vehicle body movement. FIG. 6 is a diagram showing the relationship between the transition of the movement distance y of the vehicle body 100 and the transition of the movement speed v. It is a figure which shows the drag | pulling prevention method of the wheel 100 of Example 2. FIG. 12 is a vehicle body position setting map according to a vehicle speed, a lateral acceleration, and a yaw rate according to the third embodiment. 12 is a vehicle body position setting map according to the steering angle of the third embodiment. 10 is a vehicle body position setting map according to the time from the start of turning to the end of turning according to the third embodiment. It is a figure which shows the problem of the prior art at the time of turning. It is a figure which shows the curve front cognitive effect | action of Example 3. FIG. It is a figure which shows the back confirmation effect | action of Example 3. FIG. It is a figure which shows the vehicle body position return effect | action in the turning second half of Example 3. FIG. It is a figure which shows the vehicle body moving effect | action to the turning outer side according to the vehicle speed of Example 3, a horizontal direction acceleration, and a yaw rate. It is a figure which shows the vehicle body moving effect | action to the turning outer side according to the steering angle of Example 3. FIG. It is a figure which shows the vehicle body forward movement effect | action at the time of the turning initial stage of Example 3. FIG. 12 is a vehicle body position setting map according to the vehicle speed of the fourth embodiment. It is a figure which shows the vehicle body moving effect | action to the turning outer side or turning inner side according to the vehicle speed of Example 4. FIG.

Explanation of symbols

100 body
110 Steering angle sensor (steering angle detection means)
111 Accelerator position sensor
120 Acceleration & yaw rate sensor (lateral acceleration detection means, yaw rate detection means)
130 Pitch & Roll angle sensor
140 Body speed sensor (vehicle speed detection means)
150 Proximity sensor (obstacle detection means)
300 wheel unit (suspension means)
310 Wheel unit position sensor
315 Wheel rotation speed sensor
320 Steering angle sensor
330 Drive actuator (drive means)
340 Steering actuator (steering means)
350 Tread & wheelbase change actuator (wheel position change means)
390 wheels
400 Vehicle behavior control device
500 geometry controller
510 Wheel load control device (first wheel position control means)
520 Cabin position control device (second wheel position control means)

Claims (27)

A plurality of suspension means for suspending each wheel;
Steering means provided in each suspension means for changing the direction of the wheel relative to the vehicle body;
Driving means provided on each suspension means for driving the wheels;
Wheel position changing means for moving each suspension means to an arbitrary position in the vehicle width direction with respect to the vehicle body;
First wheel position control means for commanding the wheel position changing means to change the wheel position so that the wheel load of each wheel becomes a target wheel load;
By making the distance between one of the left and right wheels and the vehicle width direction center position of the vehicle body different from the distance between the other of the left and right wheels and the vehicle width direction center position of the vehicle body, the vehicle width direction position of the vehicle body is changed from the target vehicle body position. Second wheel position control means for commanding the wheel position change means to change the wheel position,
A wheel position variable vehicle comprising: In the wheel position variable vehicle according to claim 1,
The wheel position variable vehicle characterized in that the first wheel position control means changes the wheel position so that the wheel load of each wheel becomes equal. In the wheel position variable vehicle according to claim 1 or 2,
The wheel position variable vehicle characterized in that the first wheel position control means changes the distance between the wheel and the vehicle center of gravity in the acceleration direction based on the direction of acceleration acting on the vehicle center of gravity. The wheel position variable vehicle according to any one of claims 1 to 3,
The wheel position changing means is characterized in that the wheel position changing means moves each wheel on a predetermined arcuate track. In the wheel position variable vehicle according to claim 4,
The wheel position changing means moves each wheel on one annular track, and is a wheel position variable vehicle. The wheel position variable vehicle according to any one of claims 1 to 5,
The wheel position variable vehicle, wherein the second wheel position control means changes each wheel position while maintaining a constant distance between the left and right wheels. The wheel position variable vehicle according to any one of claims 1 to 5,
The wheel position variable vehicle, wherein the second wheel position control means changes each wheel position while changing a distance between the left and right wheels. In the wheel position variable vehicle according to claim 7,
When the vehicle body is moved, the second wheel position control means maintains a constant distance between the suspension means located on the opposite side of the movement direction and the vehicle body center, while maintaining a constant distance between the suspension means located in the movement direction and the vehicle body center. A wheel position variable vehicle characterized by shortening the distance. The wheel position variable vehicle according to any one of claims 1 to 8,
Provided with obstacle detection means for detecting obstacles on the side of the vehicle,
The wheel position variable vehicle, wherein the second wheel position control means stops the movement of the vehicle body when the detected distance between the obstacle and the vehicle body is not more than a predetermined threshold value. The wheel position variable vehicle according to any one of claims 1 to 9,
The wheel position variable vehicle characterized in that the second wheel position control means limits the movement amount of the vehicle body so that the moving range of the vehicle center of gravity position is within a range on the inner side in the vehicle width direction than each suspension means. The wheel position variable vehicle according to any one of claims 1 to 10,
The second wheel position control means limits the amount of movement of the vehicle body so that when the lateral acceleration acts on the vehicle, the movement range of the center of gravity position of the vehicle is within the range on the inner side in the vehicle width direction than each suspension means. A wheel position variable device characterized by that. The wheel position variable vehicle according to any one of claims 1 to 11,
The second wheel position control means distributes the driving force of the left and right wheels so as to cancel the yaw moment generated in the vehicle when the vehicle travels straight with the vehicle width direction center position of the vehicle body approaching the left and right wheels. A wheel position variable vehicle characterized by the above. The wheel position variable vehicle according to any one of claims 1 to 11,
The second wheel position control means controls the toe angle of each wheel so as to cancel the generated wheel side slip angle when the vehicle travels straight with the vehicle width direction center position of the vehicle body approaching the left and right wheels. A vehicle with variable wheel position. The wheel position variable vehicle according to any one of claims 1 to 13,
The wheel position changing means is capable of moving each wheel on a predetermined arcuate path,
The second wheel position control means changes the position of the vehicle body by driving the driving means instead of the wheel position changing means when the angle of the suspension means with respect to the vehicle longitudinal direction exceeds a predetermined angle. A wheel position variable vehicle characterized by the above. In the wheel position variable vehicle according to claim 14,
The wheel position variable vehicle characterized in that the second wheel position control means changes the output ratio of the left and right wheel position changing means or the driving means according to the angle of each suspension means with respect to the longitudinal direction of the vehicle. In the wheel position variable vehicle according to claim 7,
The wheel position variable vehicle, wherein the second wheel position control means fixes the position of the suspension means located on the opposite side of the moving direction with respect to the vehicle body when moving the vehicle body.
The wheel position variable vehicle, wherein the second wheel position control means fixes the positional relationship between the suspension means and the vehicle body located on the opposite side to the moving direction when the vehicle body is moved. The wheel position variable vehicle according to claim 16,
The wheel position variable vehicle, wherein the second wheel position control means controls the toe angle of the wheel so that the slip angle of the wheel to be moved becomes zero. In the wheel position variable vehicle according to claim 7 or 17,
The second wheel position control means obtains a resultant force required by the wheel to be moved, and controls the wheel position changing means and the driving means so that energy is minimized when the resultant force is generated. Wheel position variable vehicle. The wheel position variable vehicle according to any one of claims 1 to 18,
The wheel position variable vehicle, wherein the second wheel position control means moves the vehicle body to the outside of the turn when turning. In the wheel position variable vehicle according to claim 19,
The wheel position variable vehicle, wherein the second wheel position control means moves the position of the vehicle body to the outside of the turn by bringing each wheel closer to the inside in the vehicle width direction. The wheel position variable vehicle according to claim 19 or 20,
Vehicle speed detection means for detecting the vehicle speed,
The wheel position variable vehicle according to claim 2, wherein the second wheel position control means controls the amount of movement of each wheel during turning according to the detected vehicle speed. The wheel position variable vehicle according to any one of claims 19 to 21,
A steering angle detection means for detecting the steering angle of the steering wheel;
The wheel position variable vehicle characterized in that the second wheel position control means controls the amount of movement of each wheel during turning according to the detected steering angle. The wheel position variable vehicle according to any one of claims 19 to 22,
Comprising lateral acceleration detecting means for detecting the lateral acceleration of the vehicle;
The wheel position variable vehicle according to claim 2, wherein the second wheel position control means controls the amount of movement of each wheel during turning according to the detected lateral acceleration. The wheel position variable vehicle according to any one of claims 19 to 23,
A yaw rate detecting means for detecting the yaw rate of the vehicle;
The wheel position variable vehicle, wherein the second wheel position control means controls the amount of movement of each wheel during a turn according to the detected yaw rate. The wheel position variable vehicle according to any one of claims 19 to 24,
The wheel position changing means can move each wheel in the vehicle longitudinal direction,
The wheel position variable vehicle, wherein the second wheel position control means moves the vehicle body to the front side of the vehicle at the beginning of turning. The wheel position variable vehicle according to any one of claims 19 to 25,
Vehicle speed detection means for detecting the vehicle speed,
The second wheel position control means moves the vehicle body to the outside of the turn in a low vehicle speed range where the detected vehicle speed is equal to or lower than a low vehicle speed threshold value, and in a medium and high vehicle speed range where the vehicle speed exceeds the low vehicle speed threshold value. A wheel position variable vehicle characterized by moving the vehicle body to the inside of the turn. In a wheel position variable vehicle provided with wheel position changing means for moving a plurality of suspension means for suspending each wheel to an arbitrary position in the vehicle width direction with respect to the vehicle body,
At the time of sudden acceleration where the acceleration of the vehicle exceeds a predetermined acceleration threshold value, wheel load movement control is performed to change the wheel position so that the wheel load of each wheel becomes the target wheel load,
During slow acceleration when the vehicle acceleration is less than the acceleration threshold, the distance between one of the left and right wheels and the center position in the vehicle width direction of the vehicle body, and the distance between the other of the left and right wheels and the center position in the vehicle width direction of the vehicle body A wheel position control method characterized by executing a cabin position movement control for changing the wheel position so that the vehicle width direction position of the vehicle body becomes a target vehicle body position by making the difference.

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