JP7632124B2 - Rocker bogie car - Google Patents

Description

The present invention relates to a rocker bogie vehicle.

Generally, it is difficult for a mobile device that runs on wheels to travel on rough terrain, and therefore technological development is underway to enable such a mobile device to travel on rough terrain.
An example of such technology is the rocker bogie mechanism.
Furthermore, mobility devices that run on wheels are required to have not only technology that enables them to run on rough ground, but also the ability to overcome steps.

Patent Document 1, an example of conventional technology, discloses an omnidirectional vehicle that can overcome unevenness and steps on the ground and travel freely on a floor surface that has unevenness and steps.

Patent Document 2, another example of conventional technology, discloses a running device that combines strength with the ability to navigate uneven surfaces.

Patent No. 3559826 Patent No. 6708488

However, the above conventional technology leaves room for improvement in order to enable quick travel in all directions, and there is a particular need for technology that enables quick travel in all directions on narrow travel surfaces.

The present invention has been made in consideration of the above, and aims to provide a rocker bogie vehicle that can travel on rough terrain, has the ability to overcome steps, and can travel quickly in all directions.

One aspect of the present invention that solves the above-mentioned problems and achieves the object is a rocker bogie car with a total of six wheels, with a pair of front wheels, middle wheels, and rear wheels on each side, and includes a bogie link on which the front wheels and middle wheels are each journaled, a rocker link on which the rear wheels are journaled, and a main body connected to the rocker link. The bogie link is journaled on the main body or the rocker link and can rotate freely or dynamically, and the rocker link is fixed to the main body. The front wheels and the rear wheels are supported on the outer periphery of the main wheels at an inclination of 45° to the axle and have a structure having a plurality of free wheels arranged in the circumferential direction, and the middle wheels are supported on the outer periphery of the main wheels at an angle of 90° to the axle and have a structure having a plurality of free wheels arranged in the circumferential direction. This is a rocker bogie car.
In addition, the front wheels and the rear wheels may be Mecanum wheels (registered trademark), and the middle wheel may be an Omniwheel (registered trademark).

In a rocker bogie vehicle with the above configuration, the steering performance can be optimized by the driving force obtained by the forward or reverse rotation of the front and rear wheels and the driving force obtained by the forward or reverse rotation of the middle wheel.

In the rocker bogie vehicle having the above configuration, the driving forces of the front wheels, the middle wheels, and the rear wheels are converted into vectors based on the relationship between the center position of the body and the positions of the front wheels, the middle wheels, and the rear wheels, and the front wheels, the middle wheels, and the rear wheels are driven by the vector-converted driving forces.

In a rocker bogie vehicle with the above configuration, the drive commands for rotating the front wheels, the middle wheels, and the rear wheels forward or backward are each independent, and it is possible to travel forward, backward, traverse to the right, traverse to the left, forward diagonal to the right, forward diagonal to the left, backward diagonal to the right, backward diagonal to the left, right spin turn, left spin turn, rotation around the right rear wheel, rotation around the right front wheel, rotation around the left rear wheel, and rotation around the left front wheel, etc.

When the rocker bogie vehicle has the above configuration and is faced with successive steps with narrow tread surfaces, such as those shown in FIG. 10, it is preferable to swing the front wheels up and place them on the steps before moving the front wheels sideways.

The rocker bogie vehicle of the above configuration further includes a steering means for remote control, the steering means having two analog joysticks, one of which is for steering the direction, and the other of which is for steering the spin turn.

The rocker bogie vehicle having the above configuration may be switchable between an autonomous driving mode in which autonomous control is performed by a control unit mounted on the vehicle body, and a remote driving mode in which remote control is performed by the steering means.

The present invention provides a rocker-bogie vehicle that can travel on rough terrain, has the ability to overcome steps, and can travel quickly in all directions.

FIG. 1 is a top view showing the configuration of a rocker bogie vehicle according to an embodiment. FIG. 2 is a side schematic diagram showing an example of the configuration of the center of gravity and wheels of a rocker bogie vehicle according to an embodiment. FIG. 3(a) is a diagram showing an example of a driving command for a rocker bogie vehicle in a polar coordinate system, and FIG. 3(b) is a diagram showing an example of the driving command shown in FIG. 3(a) decomposed into an xy vector in an xy coordinate system. FIG. 4 is a vector exploded view of the forward running speed of a Mecanum wheel in a top view. FIG. 5 is a vector exploded view of the forward travel speed of the Omni-Wheel® in a top view. FIG. 6 is a vector exploded view of the forward running speed of the rocker bogie car in a top view. FIG. 7 is a diagram showing the travel vectors of a rocker bogie vehicle in a top view. FIG. 8 is a top view schematic diagram showing the direction of travel of the rocker bogie vehicle relative to the direction of travel caused by the driving forces of six wheels: right front wheel 1aR, left front wheel 1aL, right middle wheel 1bR, left middle wheel 1bL, right rear wheel 1cR, and left rear wheel 1cL. FIG. 9 is a schematic diagram for explaining the composite vectors shown in (k), (l), (m), and (n) of FIG. FIG. 10 is a diagram showing the operation of the rocker bogie vehicle according to this embodiment when traversing a step. FIG. 11 is a diagram showing the steering means of the rocker bogie vehicle according to this embodiment. FIG. 12 is a diagram showing switching of driving modes in this embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
However, the present invention should not be construed as being limited to the following embodiments.

(Embodiment)
FIG. 1 is a top view showing the configuration of a rocker bogie vehicle 10 according to this embodiment.
The rocker bogie vehicle 10 shown in FIG. 1 has a left-right symmetrical link configuration and constitutes a six-wheeled rocker bogie vehicle body.
The right front wheel 1aR and the right center wheel 1bR are connected to a right bogie link 2R, and the left front wheel 1aL and the left center wheel 1bL are connected to a left bogie link 2L.
The right rear wheel 1cR is connected to a right rocker link 3R, and the left rear wheel 1cL is connected to a left rocker link 3L.
The right bogie link 2R and the right rocker link 3R are journaled through support holes, and the left bogie link 2L and the left rocker link 3L are journaled through support holes.
These supports are mechanisms that can actively control the rotation angle, and are called bogie link angle suspensions.
In addition, the right bogie link 2R and the left bogie link 2L may be journalled to the main body 5.
The rocker bogie car 10 shown in FIG. 1 has a right link angle motor 17R as a mechanism for controlling the angle between the right bogie link 2R and the right rocker link 3R, and a left link angle motor 17L as a mechanism for controlling the angle between the left bogie link 2L and the left rocker link 3L.
The right link angle motor 17R and the left link angle motor 17L enable angle control at the pivot support, or can create a free junction state in which no torque is applied.
Such a configuration can be realized by an actuator capable of freely controlling the rotational driving force, such as a torque motor or a Harmonic Drive (registered trademark).

When the rocker bogie vehicle shown in Figure 1 detects a step in front of it while traveling using a known sensor (not shown), the right bogie link 2R and the left bogie link 2L operate to raise the right front wheel 1aR and the left front wheel 1aL, respectively, to traverse the step.

The right front wheel 1aR, the left front wheel 1aL, the right rear wheel 1cR, and the left rear wheel 1cL are Mecanum wheels (registered trademark), and the right middle wheel 1bR and the left middle wheel 1bL are Omniwheels (registered trademark).
The six wheels, namely, the front right wheel 1aR, the front left wheel 1aL, the center right wheel 1bR, the center left wheel 1bL, the rear right wheel 1cR, and the rear left wheel 1cL, can be independently driven and controlled.
By controlling the rotation of these six wheels as forward or reverse, the rocker bogie vehicle 10 can travel forward, backward, sideways, diagonally, or make spin turns.
In the following description, the right front wheel 1aR and the left front wheel 1aL may be referred to as the front wheels 1a, the right middle wheel 1bR and the left middle wheel 1bL may be referred to as the middle wheels 1b, the right rear wheel 1cR and the left rear wheel 1cL may be referred to as the rear wheels 1c, the right bogie link 2R and the left bogie link 2L may be referred to as the bogie link 2, the right rocker link 3R and the left rocker link 3L may be referred to as the rocker link 3, and the right link angle motor 17R and the left link angle motor 17L may be referred to as the link angle motor 17.

FIG. 2 is a side schematic diagram showing an example of the configuration of the center of gravity and wheels of the rocker bogie vehicle 10 according to this embodiment.
The weight mg of the body of the rocker bogie car 10, the force N3 supported by the front wheel 1a on the ground, the force N2 supported by the middle wheel 1b on the ground, and the force N1 supported by the rear wheel 1c on the ground are N1 = N2 = N3, and mg = N1 + N2 + N3, and the rocker bogie car 10 is configured to be balanced.
The distance between the front wheel 1a and the axle support is A1.
The distance between the center ring 1b and the journal is A2.
The distance between the position of the center of gravity of the rocker bogie car 10 and the position of the pivot of the bogie link 2 is B1,
If the distance between the position of the center of gravity of the rocker bogie car 10 and the position of the rear wheel 1c of the rocker link 3 is B2, then from the balance of the moments, A2 x N2 = A1 x N3, B2 x N1 = B1 x (N2 + N3), and A1 = A2, B2 = 2 x B1.

The right front wheel 1aR, the left front wheel 1aL, the right rear wheel 1cR, and the left rear wheel 1cL shown in FIG. 1 are Mecanum wheels (registered trademark), and each main wheel has a plurality of free wheels aligned in the circumferential direction and supported rotatably at an angle of 45° to the axle on its outer periphery.
The diagonal lines in the right front wheel 1aR, the left front wheel 1aL, the right rear wheel 1cR and the left rear wheel 1cL shown in FIG. 1 indicate the direction of the rotation axis of the freewheel.

The main wheel, the right front wheel 1aR, is connected to and driven by a motor 14R, the main wheel, the left front wheel 1aL, is connected to and driven by a motor 14L, the main wheel, the right rear wheel 1cR, is connected to and driven by a motor 16R, and the main wheel, the left rear wheel 1cL, is connected to and driven by a motor 16L.
The motors 14R, 14L, 16R, 16L are each independent, and the main wheels, the front right wheel 1aR, the front left wheel 1aL, the rear right wheel 1cR, and the rear left wheel 1cL, can each be controlled independently.

The right center wheel 1bR and the left center wheel 1bL shown in FIG. 1 are Omniwheels (registered trademark), and each main wheel has a plurality of free wheels aligned in the circumferential direction and supported rotatably at 90° to the axle on its outer periphery.
The horizontal lines in the right middle wheel 1bR and the left middle wheel 1bL shown in FIG. 1 indicate the direction of the rotation axis of the freewheel.

The main wheel of the middle right wheel 1bR is connected to and driven by a motor 15R, and the main wheel of the middle left wheel 1bL is connected to and driven by a motor 15L.
The motors 15R, 15L are independent of each other, and the main wheel of the middle right wheel 1bR and the main wheel of the middle left wheel 1bL can each be controlled independently.
In the following description, the motors 14R and 14L may be referred to as motor 14, the motors 15R and 15L may be referred to as motor 15, and the motors 16R and 16L may be referred to as motor 16.

As described above, the rocker bogie vehicle 10 can move freely forward, backward, left and right thanks to a combination of six wheels: the right front wheel 1aR, the left front wheel 1aL, the right center wheel 1bR, the left center wheel 1bL, the right rear wheel 1cR and the left rear wheel 1cL.

The rocker bogie vehicle 10 according to this embodiment can be controlled by a joystick or the like, and the traveling direction and speed are managed by the joystick or the like.
FIG. 3(a) is a diagram showing an example of a driving command for a rocker bogie vehicle in a polar coordinate system, and FIG. 3(b) is a diagram showing an example of the driving command shown in FIG. 3(a) decomposed into an xy vector in an xy coordinate system.
In FIG. 3A, the angle command θ in the front direction starts from 0 and goes from -180° counterclockwise to +180° clockwise, and the speed command V goes from 0 to 120. If the rocker bogie vehicle is made to travel at a speed V in the angle +θ direction, then the x-direction speed command Vx = Vsinθ and the y-direction speed command Vy = Vcosθ.

In the rocker bogie vehicle 10 according to this embodiment, the right front wheel 1aR, the left front wheel 1aL, the right rear wheel 1cR and the left rear wheel 1cL are Mecanum wheels (registered trademark), and the right middle wheel 1bR and the left middle wheel 1bL are Omni wheels (registered trademark), so that the control equation can be constructed based on the inverse kinematics equation of the Mecanum wheel (registered trademark) and the Omni wheel (registered trademark) as the operating principle.

FIG. 4 is a top view showing vector decomposition of the forward running speed of a Mecanum wheel in a top view.
However, in FIG. 4, the axial direction of the Mecanum wheel (registered trademark) is represented by diagonal lines to represent the driving force on the contact surface.
Therefore, the inclination of the diagonal line differs by 90 degrees from the Mecanum wheel (registered trademark) axis at the top of the Mecanum wheel (registered trademark) in the top view of Figure 1.
First, assuming that the rotational speed of a wheel is ω and the wheel radius is r, then ω _i = rv _i (i is a subscript indicating each wheel).
The length between the centers of the left and right wheels of the vehicle body is defined as a wheel width 2a, and the length between the centers of the front and rear wheels of the vehicle body is defined as a tread width 2b.
Also, the length from the center of the vehicle body to each wheel is defined as length l.
Consider the case where the rocker bogie vehicle 10 according to this embodiment moves according to a velocity vector (v _x , v _y ) without rotation in the vehicle body coordinate system (x, y).
Mecanum wheels (registered trademark) slide in a 45° direction using multiple roller wheels (barrel-shaped freewheels) that rotate at a 45° inclination to the axle.
A roller wheel (barrel-shaped free wheel) that rotates in the sliding direction does not generate friction with the ground and therefore no driving force.
The OmniWheel® glides axially on a number of roller wheels (barrel-shaped freewheels) that rotate at 90° to the axle.

The diagonal lines in the right front wheel 1aR represent the axial direction of the roller wheel (barrel-shaped free wheel) in the top view.
With the vehicle body as the center, the right front wheel 1aR will be considered as an example.
In this case, the velocity vector moving in the x-axis direction around the center of the vehicle body is defined as x, the velocity vector moving in the y-axis direction is defined as y, and the vector rotating counterclockwise around the center of the vehicle body is defined as θ.
Note that these vectors are indicated by dots in the formula.

The running speed of the wheel generated from the rotational speed of the wheel is perpendicular to the wheel axis, but in reality the roller wheels (barrel-shaped freewheels) are tilted at 45 degrees, so the generated speed is multiplied by cos(π/4), and the remainder is the rolling of the rollers inside the Mecanum, so no driving force is generated in this direction.
Using these, the wheel running speed v1 is expressed as follows:
First, using the diameter r of the Mecanum wheel (registered trademark), the following equation (1) is established between the rotational speed _ω1 of the wheel and the running speed _v1 of the wheel.

Furthermore, for the actual generated velocity v1', we establish the vector balance equation shown in equation (2) below.

By expanding and summarizing the above equation, we obtain the following equation (3).

FIG. 5 is a vector exploded view of the forward travel speed of the Omni-Wheel® in a top view.
In the case of an Omniwheel (registered trademark), the x-axis direction is free.
Therefore, the velocity generated when the Omni Wheel rotates acts only in the y and θ directions.
Here, we consider the right wheel Omniwheel (registered trademark) as an example.
From the relationship shown in FIG. 5, the traveling speed v2 of the Omni Wheel (registered trademark) can be expressed by the following equations (4) and (5).

FIG. 6 is a top view showing vector decomposition of the forward running speed of the rocker bogie car in a top view.
However, in FIG. 6, the axial direction of the Mecanum wheel (registered trademark) is represented by diagonal lines to represent the driving force on the contact surface.
Next, we will consider the running speed when the front and rear wheels are Mecanum wheels (registered trademark) and the middle wheel is an Omni wheel (registered trademark).

For the x, y, and θ of the vehicle body at this time, the following equation (6) is formulated for a four-wheel Mecanum wheel (registered trademark) consisting of the front and rear wheels, in the same manner as in the derivation of equation (2) above.

Rearranging the above gives us the following equation (7).

Next, similarly to the derivation of equation (5) above, the middle wheel of the Omniwheel (registered trademark) is expressed by the following equation (8).

In other words, if the rotational speed of each wheel is identified using x, y, and θ, the following equation (9) is established.

The running speed of the machine at each wheel rotation speed can be expressed by the following equation (10) by solving the simultaneous equations using the above equation (9).

Figure 7 shows the travel vector of a rocker bogie vehicle in a top view.

As described above, for the rocker bogie vehicle 1, the velocity vector moving in the x-axis direction, the velocity vector moving in the y-axis direction, and the vector rotating counterclockwise around the center of the vehicle body of each wheel can be represented by the wheel rotational speed _ωi of each wheel, and driving control can be performed using this.

According to this embodiment, in a six-wheel rocker bogie vehicle capable of traversing steps, the front wheels have a mechanism for climbing steps, or a mechanism for dynamically raising the bogie link using a bogie link angle suspension with the front wheels, the front and rear wheels are Mecanum wheels (registered trademark) and the middle wheels are Omniwheels (registered trademark), making it possible to control the driving and enabling quick omnidirectional driving even in narrow spaces.
Furthermore, according to this embodiment, the steering (direction steering means) can be made smaller and lighter.
Furthermore, according to this embodiment, it is possible to control the running of the vehicle by the driving force of each wheel, without providing a suspension function for determining the running direction of each of the six wheels.

Next, the rotation of the right front wheel 1aR, the left front wheel 1aL, the right center wheel 1bR, the left center wheel 1bL, the right rear wheel 1cR and the left rear wheel 1cL and the behavior of the rocker bogie vehicle 10 will be described below.
FIG. 8 is a top view schematic diagram showing the direction of travel of the rocker bogie vehicle 10 relative to the direction of travel caused by the driving forces of the six wheels: the right front wheel 1aR, the left front wheel 1aL, the right middle wheel 1bR, the left middle wheel 1bL, the right rear wheel 1cR, and the left rear wheel 1cL.

In FIG. 8, the diagonal lines of the Mecanum Wheel (registered trademark) indicate the axial direction of the freewheel, but when viewed from the contact surface side, the axial direction of the roller wheel is perpendicular to the diagonal lines.
The right front wheel 1aR, the left front wheel 1aL, the right rear wheel 1cR, and the left rear wheel 1cL are Mecanum wheels (registered trademark),
The right middle wheel 1bR and the left middle wheel 1bL are Omniwheels (registered trademark).

FIG. 8 shows a basic running mode based on the velocity vector generated from the rotational speed ω of each wheel of the rocker bogie vehicle 10 and the result of the rotation vector.
The direction of the arrow on the wheel indicates the direction of the rotational speed ω, and the magnitude component of the arrow on the wheel indicates the magnitude of the rotational speed ω.
The basic running mode shown in FIG. 8 is operated by the steering mechanism, and is converted into coordinates from the direction of the stick and the magnitude of the inclination of the stick, and is expanded into the rotational speed ω of each wheel.
The small arrow in the middle in FIG. 8 represents the rotational speed generated by a command for a fast running speed.
The arrows of each wheel in FIG. 8 represent the rotational speed ω of each wheel, which is the result of operation by a steering mechanism as shown in FIG. 11 described later.
In FIG. 11 described later, the direction is specified by the tilt of the left stick, and the magnitude of the velocity is specified by the magnitude of the tilt of the left stick.
Furthermore, as shown in FIG. 12 described later, the operation of the left stick is converted from analog coordinates to polar coordinates, and then converted from the polar coordinates to Cartesian coordinates before the rotational speed is calculated. Therefore, the rotational speed ω of each wheel is uniquely determined from the result of the steering mechanism described above.

As shown in (a) of FIG. 8, when the right front wheel 1aR, the left front wheel 1aL, the right center wheel 1bR, the left center wheel 1bL, the right rear wheel 1cR, and the left rear wheel 1cL are all rotated forward, the rocker bogie vehicle 10 moves forward.
As shown in (b) of FIG. 8, when the right front wheel 1aR, the left front wheel 1aL, the right center wheel 1bR, the left center wheel 1bL, the right rear wheel 1cR and the left rear wheel 1cL are all reversed, the rocker bogie car 10 moves backward.

As shown in (c) of FIG. 8, when the left front wheel 1aL and the right rear wheel 1cR are rotated forward and the right front wheel 1aR and the left rear wheel 1cR are rotated in the opposite direction, the rocker bogie car 10 moves parallel to the right (right lateral movement).
As shown in (d) of FIG. 8, when the left front wheel 1aL and the right rear wheel 1cR are inverted and the right front wheel 1aR and the left rear wheel 1cL are rotated forward, the rocker bogie car 10 moves parallel to the left (left lateral movement).

As shown in (e) of FIG. 8, when the left front wheel 1aL and the right rear wheel 1cR are rotated forward and the right middle wheel 1bR and the left middle wheel 1bL are rotated forward at a small rotational speed, the rocker bogie car 10 moves diagonally forward to the right (forward right diagonal movement).
As shown in FIG. 8(f), when the right front wheel 1aR and the left rear wheel 1cL are rotated forward and the right middle wheel 1bR and the left middle wheel 1bL are rotated forward at a small rotational speed, the rocker bogie car 10 moves diagonally forward to the left (forward left diagonal movement).

As shown in FIG. 8(g), when the right front wheel 1aR and the left rear wheel 1cL are rotated in reverse and the right middle wheel 1bR and the left middle wheel 1bL are rotated in reverse at a small rotational speed, the rocker bogie car 10 moves diagonally backward to the right (backward right diagonal movement).
As shown in FIG. 8(h), when the left front wheel 1aL and the right rear wheel 1cR are rotated in reverse and the right middle wheel 1bR and the left middle wheel 1bL are rotated in reverse at a small rotational speed, the rocker bogie car 10 moves diagonally backward to the left (reverse left diagonal movement).

As shown in FIG. 8(i), when the right front wheel 1aR, the right middle wheel 1bR, and the right rear wheel 1cR are rotated in the opposite direction and the left front wheel 1aL, the left middle wheel 1bL, and the left rear wheel 1cL are rotated forward, the rocker bogie car 10 turns clockwise (right spin turn).
As shown in FIG. 8(j), when the right front wheel 1aR, the right middle wheel 1bR, and the right rear wheel 1cR are rotated forward and the left front wheel 1aL, the left middle wheel 1bL, and the left rear wheel 1cL are rotated in the opposite direction, the rocker bogie car 10 turns counterclockwise (left spin turn).

FIG. 9 is a schematic diagram for explaining the composite vectors shown in (k), (l), (m), and (n) of FIG.
By combining a plurality of the operations shown in (a) to (j) of FIG. 8, the turning operations shown in (k), (l), (m), and (n) of FIG. 8 become possible.
These turning operations are realized by a combination of basic operations as shown in FIG. 9, using velocity vectors in the x-axis and y-axis directions of each wheel due to the rotational speed ω, and a rotational vector.
As shown in (k) of FIG. 8, when a drive command is given that combines (e) and (i) of FIG. 8, the right front wheel 1aR reverses, the right middle wheel 1bR reverses at a small rotational speed, and the left front wheel 1aL, the left middle wheel 1bL and the left rear wheel 1cL each rotate forward at a large rotational speed, and the rocker bogie car 10 turns clockwise (rotates around the right rear wheel) based on the right rear wheel 1cR.
As shown in (l) of FIG. 8, when a drive command is given that combines (f) and (i) of FIG. 8, the right rear wheel 1cR reverses direction, the right middle wheel 1bR reverses direction at a small rotational speed, and the left front wheel 1aL, the left middle wheel 1bL and the left rear wheel 1cL each rotate forward at a large rotational speed, and the rocker bogie vehicle 10 turns clockwise (rotates around the right front wheel) based on the right front wheel 1aR.

As shown in (m) of FIG. 8, when a drive command is given that combines (f) and (j) of FIG. 8, the right front wheel 1aR, the right middle wheel 1bR, and the right rear wheel 1cR rotate forward at a high rotational speed, the left front wheel 1aL rotates in the opposite direction, and the left middle wheel 1bL rotates in the opposite direction at a low rotational speed, according to the composite vector shown in FIG. 9 ((f) + (j)). The rocker bogie vehicle 10 turns counterclockwise (rotates around the left rear wheel) with the left rear wheel 1cL as the reference.
As shown in (n) of FIG. 8, when a drive command is given that combines (e) and (j) of FIG. 8, the right front wheel 1aR, the right middle wheel 1bR, and the right rear wheel 1cR rotate forward at a high rotational speed, the left rear wheel 1cL rotates in the opposite direction, and the left middle wheel 1bL rotates in the opposite direction at a low rotational speed, and the rocker bogie vehicle 10 turns counterclockwise with the left front wheel 1aL as the base (rotates around the left front wheel).

In the steering means of the rocker bogie vehicle 10, direction, speed, rotation, etc. are defined as steering parameters.
From the equation (9) in the first embodiment, the running speed, running angle, rotation command, etc. for each wheel are developed.
These steering parameters provide drive instructions to the motors that drive the wheels to be used in the form of command values, speed commands, current commands, voltage commands, and the like for the servo motors.
In this embodiment, the drive system of the motor that drives the wheel and the control circuit thereof are not limited to a specific type, and may be appropriately selected.

According to this embodiment, the front and rear wheels are Mecanum wheels (registered trademark), the middle wheel is an Omniwheel (registered trademark), and by driving each wheel in a specific rotational direction, it is possible to move in a variety of ways, such as forward, backward, lateral to the right, lateral to the left, forward diagonal to the right, forward diagonal to the left, backward diagonal to the right, backward diagonal to the left, right spin turn, left spin turn, rotation around the right rear wheel, rotation around the right front wheel, rotation around the left rear wheel, and rotation around the left front wheel.

FIG. 10 is a diagram showing the operation of the rocker bogie vehicle 10 according to this embodiment when traversing a running surface having a special type of step.
The steps on the running surface shown in FIG. 10 are continuous and have narrow treads, making it difficult for the rocker bogie vehicle 10 to turn around to face the next step and then reorient itself perpendicular to the step.

The rocker bogie vehicle 10 according to this embodiment is equipped with Mecanum wheels (registered trademark) on the front wheels 1a and rear wheels 1c, and Omni wheels (registered trademark) on the middle wheels 1b, and is capable of traversing the steps on the running surface shown in FIG.
With this configuration, by controlling the drive as shown in (c) and (d) in Figure 8, the rocker bogie vehicle can be made to travel laterally.
As shown in FIG. 10, when the rocker bogie vehicle 10 according to this embodiment moves forward and detects a step, it swings up the front wheels, and rotates the front and rear wheels in a predetermined direction with the front wheels hanging over the step, to move sideways.
Then, the rocker bogie vehicle 10 moves laterally to the position where the next step is located, and then traverses the step by having the middle and rear wheels also ride up onto the step, and moves forward until the next step is detected.
Thereafter, when the rocker bogie vehicle 10 detects the next step again, it swings up the front wheels, and rotates the front and rear wheels in a predetermined direction while the front wheels are hooked on the step, thereby moving laterally.
In this way, the rocker bogie vehicle 10 according to this embodiment is capable of efficiently traversing steps by lateral movement when the step direction is not the forward direction and the step is like a staircase.

According to this embodiment, by performing the specified drive as described above, it is possible to overcome steps with special shapes, enabling efficient step traversal.

Next, the steering means of the rocker bogie vehicle will be described.
The rocker bogie vehicle 10 according to this embodiment is autonomously controlled by a computer mounted on the vehicle body, which independently controls the rotational speed of each wheel and manages the running performance of the vehicle body.
Furthermore, the rocker bogie vehicle 10 according to this embodiment can also realize autonomous driving by real-time manual operation of the computer mounted on the vehicle body.

FIG. 11 is a diagram showing the steering means of the rocker bogie vehicle 10 according to this embodiment.
The steering means shown in FIG. 11 is equipped with two analog joysticks.
The left stick, which is one of the two analog joysticks, realizes steering in directions such as forward/backward, left/right, right diagonally forward, left diagonally forward, right diagonally backward, and left diagonally backward.
The other of the two analog joysticks, the right stick, realizes right spin turn and left spin turn steering.
In addition, the analog joystick, which is the steering means shown in FIG. 11, can control the direction, speed, strength, size, etc. of the movement.
For example, it is possible to set the analog joystick so that the deeper the tilt angle, the faster the movement in the tilt direction.

The steering means of the rocker bogie vehicle 10 according to this embodiment is not limited to that shown in FIG. 11 and may be in the form of, for example, a computer game console controller.

According to this embodiment, the steering means equipped with two analog joysticks allows the rocker bogie vehicle to be driven with high operability.

In addition, the rocker bogie vehicle according to this embodiment is capable of switching between autonomous driving and remote driving.
Autonomous driving is a self-controlled driving mode in which the vehicle's driving performance is managed by autonomously controlling the rotational speed of each wheel through a computer installed in the vehicle body.
Remote driving is a driving mode in which a steering means outside the vehicle body is equipped with a control means capable of transmitting information via, for example, serial cable communication, wireless communication, public line wireless communication, etc., and the rotational speed of each wheel is controlled based on information from the steering means, thereby remotely managing the driving performance of the vehicle body.
Such mode switching can be realized by providing a selection switch, such as a selection switch or a slide switch, on the steering means as shown in FIG.

FIG. 12 is a diagram showing switching of driving modes in this embodiment.
As shown in FIG. 12, the mode switching process selects either the remote control or the autonomous control driving mode.
When the remote control procedure is selected, serial input from the communication system from the remote control is taken and the analog coordinates are converted to polar coordinates.
When serial input is selected by autonomous control, a control command is serially input from an autonomous driving processing unit (not shown) in the rocker bogie vehicle 10, and the serial buffer is converted into polar coordinates.
In any driving mode, the polar coordinates are converted into Cartesian coordinates, the Cartesian coordinates are calculated into a servo rotation speed, the servo rotation speed is servo-transmitted, and the speed is transmitted to each servo motor.
As shown in FIG. 12, by performing a selection and branching process of the driving mode, the rocker bogie vehicle 10 according to this embodiment can switch between autonomous driving and remote driving.

In remote control, analog coordinate information is transmitted from the remote control means via wireless communication such as Bluetooth (registered trademark) from a device having an analog joystick operation mechanism, or via serial communication such as public line communication, and the analog coordinate information is converted into polar coordinates, which are then converted into Cartesian coordinates to calculate the rotational speed and send driving commands to each wheel, thereby managing the driving of the vehicle body.

In autonomous control, information from sensors installed inside the vehicle and information obtained through computer processing, etc. is converted into polar coordinates, which are then converted into Cartesian coordinates to calculate the rotational speed and send driving commands to each wheel, thereby managing the vehicle's movement.

According to this embodiment, the driving mode of the rocker bogie vehicle 10 can be switched between autonomous driving and remote driving.

In this embodiment, a six-wheeled rocker bogie vehicle has been described as an example, but the present invention is not limited to this.
For example, rocker bogie vehicles with eight or more wheels are also included in the present invention.
In other words, the present invention also includes a configuration in which the front wheels attached to one end of the bogie link 2 in the traveling direction are two or more Mecanum wheels.
The present invention also includes a configuration in which the middle wheel attached to the other end of the bogie link 2 is an omniwheel having two or more wheels.
The present invention also includes a configuration in which the rear wheels attached to one end of the rocker bogie car opposite the direction of travel are two or more Mecanum wheels.
Furthermore, the present invention also includes a rocker bogie vehicle having a first bogie link and a second bogie link on each side, the first bogie link having a front wheel, a bogie link and a middle wheel, and the second bogie link having a middle wheel, a bogie link and a rear wheel.

The present invention is not limited to the above-described embodiment, but also includes various modifications in which components are added, deleted, or converted from the above-described configuration.

1a Front wheel 1aR Right front wheel 1aL Left front wheel 1b Center wheel 1bR Right center wheel 1bL Left center wheel 1c Rear wheel 1cR Right rear wheel 1cL Left rear wheel 2 Bogie link 2R Right bogie link 2L Left bogie link 3R Right rocker link 3L Left rocker link 5 Bogie 10 Rocker bogie car 14, 14R, 14L, 15, 15R, 15L, 16, 16R, 16L Motor 17 Link angle motor 17R Right link angle motor 17L Left link angle motor

Claims (6)

A rocker bogie vehicle with a total of six wheels, with a pair of front wheels, a pair of middle wheels, and a pair of rear wheels on the left and right,
a bogie link to which the front wheels and the center wheels are journalled;
A rocker link on which the rear wheel is journalled;
a body connected to the rocker link,
The bogie link is pivotally supported on the main body or the rocker link and is capable of free rotation or dynamic rotation;
The rocker link is fixed to the body,
The front wheels and the rear wheels are supported rotatably at an angle of 45° to the axle on the outer periphery of the main wheel and have a structure including a plurality of free wheels arranged in a circumferential direction,
The center wheel is supported on the outer periphery of the main wheel so as to be rotatable at an angle of 90° to the axle, and has a structure including a plurality of free wheels arranged in a circumferential direction;
The vehicle moves laterally in the other direction by rotating the front wheels of one of the left and right vehicles and the rear wheels of the other of the left and right vehicles forward, rotating the rear wheels of the one of the left and right vehicles and the front wheels of the other of the left and right vehicles in reverse, and stopping both the left and right middle wheels,
the front wheels, the middle wheels, and the rear wheels of the one of the left and right sides are rotated forward, and the front wheels, the middle wheels, and the rear wheels of the other of the left and right sides are rotated in the opposite direction, thereby turning to the other left or right side;
rotating the front wheels, middle wheels, and rear wheels of the one of the left and right vehicles forward, rotating the front wheels of the other of the left and right vehicles in reverse, and rotating the middle wheels of the other of the left and right vehicles in reverse at a rotation speed slower than that of the front wheels of the other of the left and right vehicles, thereby turning to the other of the left and right vehicles with the rear wheels of the other of the left and right vehicles as a reference;
A rocker bogie vehicle that turns to the other left or right side based on the other left or right front wheels by rotating the front wheels, middle wheels, and rear wheels of the one left or right side forward, reversing the rear wheels of the other left or right side, and reversing the middle wheels of the other left or right side at a rotation speed slower than that of the rear wheels of the other left or right side . In an xy coordinate system with the center of the body of the rocker bogie vehicle as the origin, a velocity vector moving in the x-axis direction around the center of the body is x, a velocity vector moving in the y-axis direction around the center of the body is y, a vector rotating counterclockwise around the center of the body is θ, the width in the x-axis direction from the center of the body to the centers of the front wheels, the middle wheels, and the rear wheels is a, the width in the y-axis direction from the center of the body to the centers of the front wheels and the rear wheels is b, and the radius of the front wheels, the middle wheels, and the rear wheels is r. The front, middle, and rear wheels on the left or right side and the front, middle, and rear wheels on the other left or right side have rotational speeds ω shown in the following formula (1), ₁ , ω ₂ , ω ₃ , ω ₄ , ω ₅ , ω ₆ 2. The rocker bogie vehicle according to claim 1, wherein the rocker bogie vehicle is driven by a

The rocker bogie vehicle according to claim 1, in which the front wheels are swung up and placed on the step when there are successive steps with a narrow tread, and then the front wheels are moved sideways. Further comprising a steering means for remote control,
The steering means includes two analog joysticks;
One of the two analog joysticks provides directional steering;
The rocker bogie vehicle according to claim 1, wherein the other of the two analog joysticks performs steering for spin turns. An autonomous driving mode in which autonomous control is performed by a control unit installed in the vehicle body;
The rocker bogie vehicle according to claim 4 , wherein a remote driving mode in which remote operation by the steering means is performed can be switched. The front and rear wheels are Mecanum wheels (registered trademark);
2. The rocker bogie vehicle according to claim 1, wherein the middle wheel is an Omni Wheel.

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