JP2010030360A - Spherical body driving type omnidirectional moving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spherical body driving type omnidirectional moving device allowing reduction of manufacturing cost with being hardly affected by unevenness, etc. of a floor surface and with high stability during traveling. <P>SOLUTION: This moving device has: three spherical bodies 11 to 13 for driving arranged at vertex positions of a triangle in plane view and having the same shape; and three driving means 14 to 16 for simultaneously rotating and driving the spherical body 11 and the spherical body 12, the spherical body 12 and the spherical body 13, and the spherical body 13 and the spherical body 11, which are arranged adjacently to each other, in the same direction. In this case, it is desirable that the triangle is an equilateral triangle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a sphere-driven omnidirectional movement device that can move freely even in a narrow place, and more specifically, for example, a sphere drive that can be used for home robots, electric wheelchairs (welfare related), industrial transport carts, and the like. The present invention relates to an omnidirectional mobile device.

Conventionally, as an omnidirectional moving device (hereinafter, also simply referred to as a moving device), a Roller Wheel (omni wheel) method that can move relatively quickly and is easy to control has been used.
This method uses an omni wheel (hereinafter also simply referred to as a wheel) in which a plurality of free-sliding rollers are arranged on the outer periphery.
By comprising in this way, the movement of a moving apparatus is enabled by the side skid of a wheel (for example, refer nonpatent literature 1).

However, the free rollers provided on each wheel are mounted in two rows in the width direction of the wheel and alternately (in a zigzag manner), so depending on the rotational position of the wheel, the contact position between the wheel and the floor surface Therefore, the behavior becomes unstable when the moving device tries to draw a curved track or when the traveling surface is not uniform. Further, since the free roller is provided on the outer peripheral portion of the wheel, there are various problems such as slippage in the axial center (axle) direction of the wheel and lack of stability in translational motion and rotational motion.
For this reason, if the friction between one wheel and the floor surface is extremely small due to the influence of unevenness of the floor surface, the running stability may be significantly impaired.
Therefore, since the above-described method requires that the surface state of the floor surface is uniform, for example, it is not suitable for traveling on a carpet, and the place of use is greatly limited.

On the other hand, the sphere driving method has few research examples yet, but has a feature that the structure can be simplified and the speed unevenness does not occur when moving in any direction. Moreover, since it drives with a spherical body, for example, stable running is possible even on a carpet.
As a moving device using such a sphere driving system, for example, two driving spheres each provided with two driving motors, and three driving spheres each provided with one driving motor. (For example, see Non-Patent Document 2), and further, two driving motors are provided on each of four driving spheres (for example, see Non-Patent Document 3).

Shoichiro Fujisawa, Keiji Okubo, Yasunari Shidama, Hiroo Yamaura, "Kinematics and running characteristics of four-wheel independent drive omnidirectional mobile robot", Transactions of the Japan Society of Mechanical Engineers, December 1996, Vol. 62, No. 604, p. 149-155 Naoki Matsumoto, Shigeru Takeda, Shinji Iida, Masatsugu Ito, “Movement and control of omnidirectional movement mechanism using three spheres”, Transactions of the Japan Society of Mechanical Engineers, August 1994, Vol. 60, No. 576, p. 266-273 Kensuke Yamada, Kyosei Miyamoto, Seiichi Usui, “Study on Omnidirectional Movement Mechanism Using Four Spheres”, Transactions of the Japan Society of Mechanical Engineers, August 2005, Vol. 71, No. 708, p. 127-132

However, the moving device using the conventional sphere driving method still has the following problems to be solved.
Since the moving device provided with two driving motors on each of the two driving spheres is arranged in contact with one driving sphere so that the rotation axes of the two driving motors are orthogonal to each other, However, a total of four drive motors are required.
Since the degree of freedom of movement in the plane is a total of three degrees of freedom of translational motion and rotational motion, in principle, three drive motors are sufficient. For this reason, the use of the four drive motors itself is useless and leads to an increase in manufacturing cost, which is not economical.

Further, in the moving device in which one driving motor is provided for each of the three driving spheres, each driving sphere is driven by one driving motor, so the above-described driving motor is not wasted. In this case, since the driving sphere is used, for example, stable running can be performed even on a carpet, and the applicable range of the floor surface on which the vehicle can travel is widened as compared with the omni wheel method described above. However, the principle of motion is the same as that of the omni-wheel system, so if the friction between one driving sphere and the floor surface is extremely small, the stability of running may be significantly impaired due to the unevenness of the floor surface. There is sex.
Furthermore, the moving device in which each of the four driving spheres is provided with two driving motors uses four driving spheres and requires a total of eight driving motors. It is not economical because it leads to a rise.

The present invention has been made in view of such circumstances, and it is intended to provide a spherically driven omnidirectional movement device that can reduce manufacturing costs, is not easily affected by unevenness of the floor surface, and has high stability during traveling. Objective.

The sphere-driven omnidirectional movement device according to the present invention that meets the above-described object includes three driving spheres having the same shape arranged at the apex position of a triangle in plan view, and the driving spheres arranged adjacent to each other. And three driving means for simultaneously rotating in the same direction.
In the sphere-driven omnidirectional movement device according to the present invention, the triangle is preferably a regular triangle.

In the sphere-driven omnidirectional movement device according to the present invention, the driving means includes a rotor that simultaneously contacts the circumferential surface of the driving spheres arranged adjacent to each other, and a driving motor that rotationally drives the rotor. It is preferable.
In the sphere-driven omnidirectional movement device according to the present invention, the driving means includes a rotor that contacts each of the peripheral surfaces of the driving spheres arranged adjacent to each other, and a power transmission belt that connects the two rotors. It is preferable to have a drive motor that rotationally drives one of the two rotors.

In the sphere-driven omnidirectional movement device according to the present invention, the lateral positioning of each driving sphere is brought into contact with the side surface of the driving sphere at the same height as the rotation center of the driving sphere, and the drive It is preferable to use a wheel caster that can rotate the spherical body in the vertical direction.
In the sphere-driven omnidirectional movement device according to the present invention, it is preferable to use a ball-type caster that can rotate in all directions in contact with the circumferential surface of the driving sphere for lateral positioning of the driving spheres.

In the sphere-driven omnidirectional movement device according to the present invention, each of the driving spheres is provided on a carriage provided with a drop-off prevention cover having an opening formed at a lower portion in accordance with an arrangement position of each of the driving spheres, It is preferable that the lower portions of the driving spheres are protruded from the openings, respectively, and the driving spheres are prevented from falling off the carriage.
In the sphere-driven omnidirectional movement device according to the present invention, it is preferable that a brush member that contacts the surface of each driving sphere is provided inside the opening of the drop-preventing cover.

Since the sphere-driven omnidirectional moving device according to the first to eighth aspects includes the three driving spheres and the three driving means, the driving means is not wasted, and the manufacturing cost can be reduced, which is economical.
In addition, since each driving means simultaneously drives and drives the driving spheres arranged adjacent to each other, the rotation direction of each driving sphere and the sphere-driven omnidirectional movement can be controlled by controlling the operation of each driving means. The moving direction of the device can be matched. As a result, no side slip occurs in each driving sphere, so that it is possible to provide a sphere-driven omnidirectional movement device that is not easily affected by unevenness on the floor surface and has high stability during traveling.
Accordingly, the sphere-driven omnidirectional moving device can be used for, for example, a home robot, an electric wheelchair (welfare related), an industrial transport carriage, and the like.

In particular, the sphere-driven omnidirectional movement device according to claim 2 arranges the three driving spheres at the vertex positions of the equilateral triangle in plan view, so that the three driving spheres are centered on the center of gravity of the equilateral triangle. It will be arranged every 120 degrees. As a result, the travel pattern of the sphere-driven omnidirectional mobile device is determined on the basis of the line connecting the center of gravity of the equilateral triangle and each vertex position with respect to the region of ± 60 degrees centered on the center of gravity. Therefore, the traveling pattern can be simplified.

In the sphere-driven omnidirectional moving device according to claim 3, the driving means is constituted by the rotor that simultaneously contacts the peripheral surface of the driving sphere arranged adjacent to the driving sphere, and the driving motor that drives the rotor. The arranged driving spheres can be simultaneously rotated with a simple configuration.

According to a fourth aspect of the present invention, there is provided a sphere-driven omnidirectional moving device that includes a rotor that is in contact with a circumferential surface of a driving sphere arranged adjacent to each other, a power transmission belt that connects the rotors, and a drive that drives the rotor. Since the driving means is constituted by a motor, for example, even when it is desired to increase the interval between the central positions of the driving spheres arranged adjacent to each other, the driving spheres and the rotor can be simultaneously driven without increasing the size.

Since the sphere-driven omnidirectional movement device according to claim 5 uses a wheel caster for lateral positioning of each drive sphere, for example, dust attached to the surface of the drive sphere adheres to the wheel caster. However, it is possible to reduce the possibility that the waste will stay in the wheel caster. As a result, rotation of the wheel type caster is performed stably, so that the sphere-driven omnidirectional movement device can be prevented from moving in a direction different from the instruction, and the maintenance frequency of the sphere-driven omnidirectional movement device is also reduced. it can.
In addition, the wheel type caster contacts the side surface of the driving sphere at the same height as the rotation center of the driving sphere, and the driving sphere can be rotated in the vertical direction. The wheel type caster can be rotated in accordance with the rotation direction of the driving sphere, except when rotating around the contact position. Thereby, since the sliding of the driving sphere with respect to the wheel caster can be reduced, the damage of the driving sphere can be reduced, and the replacement frequency of the driving sphere can be reduced.

The sphere-driven omnidirectional movement device according to claim 6 uses a ball-type caster that can rotate in all directions for lateral positioning of each drive sphere, so that the ball-type caster is attached to any of the peripheral surfaces of the drive sphere. Even if it is brought into contact with the position, the ball caster can be rotated in accordance with the rotation direction of the driving sphere. Thereby, since the sliding of the driving sphere with respect to the ball type caster can be reduced, damage to the driving sphere can be reduced, and the replacement frequency of the driving sphere can be reduced.

The sphere-driven omnidirectional movement device according to claim 7 is provided such that each driving sphere is provided on a carriage, and a lower portion of each driving sphere is protruded from an opening of a drop-off prevention cover provided on a lower part of the carriage. Therefore, even when each driving sphere is rotationally driven by the driving means, each driving sphere can be rotationally driven without falling off the carriage.
The spherically driven omnidirectional movement device according to claim 8 is provided with a brush member in contact with the surface of each driving sphere inside the opening of the dropout prevention cover, so that the dust adhered to each driving sphere. And dirt can be removed simultaneously with the traveling of the carriage.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1A and 1B, a sphere-driven omnidirectional moving device (hereinafter also simply referred to as a moving device) 10 according to an embodiment of the present invention is a vertex of an equilateral triangle in plan view. Three driving spheres 11 to 13 arranged at positions P1, P2, and P3, a driving sphere 11 and a driving sphere 12, which are arranged adjacent to each other, a driving sphere 12 and a driving sphere 13, and a driving sphere. 13 and three driving means 14 to 16 for driving and rotating the driving sphere 11 in the same direction at the same time, and is a device that can move on the floor surface 17 in all directions. The operation of each of the driving units 14 to 16 is controlled by a control unit (not shown). This will be described in detail below.

As shown in FIGS. 1 (A) and 1 (B), the moving device 10 has a carriage 19 having a flat plate-like mounting table 18 attached to the upper part thereof. The control unit described above is wired and disposed at a position different from the carriage 19, but may be wireless or provided on the carriage 19.
The mounting table 18 is made of plastic or metal and has a hexagonal shape in a plan view. However, the mounting table 18 is not limited to this shape. For example, other polygons and corners of the polygons. The shape may be round, or may be circular or elliptical.
Below the mounting table 18, the driving spheres 11 to 13 are rotatably provided via supporting ball casters 20 to 22 that are attached to the lower surface 23 of the mounting table 18 and can rotate in all directions. ing. Each of the supporting ball type casters 20 to 22 is in contact with the apex position of the driving spheres 11 to 13.

Each of the driving spheres 11 to 13 is made of, for example, an elastic material such as silicone resin or urethane resin, and has a diameter of, for example, about 5 to 15 cm (preferably 7 to 10 cm) and the same shape (same diameter). ). As described above, since the driving spheres 11 to 13 have the same shape, the lower surface 23 of the mounting table 18 is parallel to the floor surface 17, and the rotation speed when the driving spheres 11 to 13 rotate is as follows. It will be the same.
As shown in FIG. 1A, the rotation centers of the driving spheres 11 to 13 are equiangular (120 degrees) around the center of gravity G of the equilateral triangle in plan view, and equidistant from the center of gravity G. They are respectively arranged (that is, arranged at vertex positions P1, P2, and P3 of the equilateral triangle).

As shown in FIGS. 1A and 1B, the driving means 15 (the driving means 14 and 16 are also the same) simultaneously contact the peripheral surfaces of the driving sphere 12 and the driving sphere 13 arranged adjacent to each other. A rotor 24 and a drive motor 25 that rotationally drives the rotor 24 are included.
The rotor 24 has its rotational axis 26 parallel to the floor surface 17, and the height of the axial center is the same as the rotational center of the driving spheres 12, 13. As described above, the driving sphere 12 and the driving sphere 13 are arranged on a line connecting the rotation centers in plan view. The diameter of the rotor 24 is smaller than the diameters of the driving sphere 12 and the driving sphere 13.
Accordingly, the two driving spheres 12 and 13 can be simultaneously rotated in the same direction without bringing the rotor 24 into contact with the floor surface 17.

The driving means can also be constituted by driving means 27 to 29 shown in FIGS. 2 (A) and 2 (B).
This driving means 28 (same for the driving means 27 and 29) is the power for connecting the rotors 30 and 31 that are in contact with the peripheral surfaces of the driving spheres 12 and 13 arranged adjacent to each other and the two rotors 30 and 31, respectively. It has a transmission belt 32 (for example, a chain belt) and a drive motor 33 that rotationally drives one rotor 30 (or the rotor 31).
The rotors 30 and 31 are arranged so that the axes of the rotation shafts 34 and 35 are parallel to the floor surface 17 and the height position of the axes is the same as the rotation center of the driving spheres 12 and 13. It is arranged on a line connecting the rotation centers of the driving sphere 12 and the driving sphere 13 in plan view so as to be in the vertical position.
Thereby, even when the distance between the centers of the adjacent driving spheres 12 and the driving spheres 13 is changed according to the usage, the two driving spheres 12 and 13 can be simultaneously rotated in the same direction.

As shown in FIGS. 1 (A) and 1 (B), the driving sphere 11 (and the driving spheres 12 and 13 are the same) has a circumferential surface attached to a wheel caster 37 attached to the inner side surface 36 of the carriage 19. In contact.
The wheel caster 37 is a conventionally known one that can rotate in one direction, and is attached to the rotor 24 of the driving means 14 and 16 so as to sandwich the driving sphere 11 therebetween. Thus, since the wheel type caster 37 is rotatable in one direction, it is attached to the inner side surface 36 of the carriage 19 so as to guide the driving sphere 11 so as to be rotatable in the vertical direction (vertical direction). The number of wheel casters 37 may be one for one driving sphere, but may be two or more.
Thereby, since the driving sphere 11 is sandwiched between the two rotors 24 and the wheel casters 37, the driving sphere 11 is positioned in the lateral direction.

Here, the driving principle of the moving device 10 will be described below using the driving sphere 13 and the rotor 24.
In the sphere-driven moving device 10, as shown in FIG. 3, the rotor 24 attached to the drive motor 25 causes the drive sphere 13 to move through the frictional force generated between the drive sphere 13 and the traveling surface. Propulsion is obtained by rotating. Here, f is a frictional force between the rotor 24 and the driving sphere 13 and F is a frictional force between the driving sphere 13 and the running surface.
In the moving device 10, as described above, the wheel-type caster 37 that holds the rotation of the driving sphere 13 and the rotor 24 are arranged on the side surface of the driving sphere 13 so as to sandwich the driving sphere 13. Drive.

Here, the mounting position of the rotor 24 is adjusted to satisfy f> F in order to eliminate slippage between the rotor 24 and the rotation direction of the driving sphere 13. Since the contact between the driving sphere 13 and the running surface is a rolling contact, no side slip occurs even when the moving device 10 moves in an arbitrary direction.
In order to keep the rotation of the driving sphere 13 smoothly, as shown in FIG. 4A, the rotor 24 and the wheel caster 37 must be in contact in a horizontal plane including the centers of the three spheres. On the other hand, as shown in FIG. 4B, when the rotor 24 is brought into contact with the position shifted from the horizontal plane, the rotation axis of the driving sphere 13 may not be directed in the horizontal direction.

Here, when the rotation axis of the driving sphere 13 faces the horizontal direction with respect to the floor surface, as shown in FIG. 5A, the distance from the rotation axis to the ball contact point is the radius of the driving sphere 13. It is constant at the same value as R.
On the other hand, when the rotation axis of the driving sphere 13 does not face the horizontal direction, the distance from the rotation axis to the ball contact point on the running surface is equal to the radius R of the driving sphere 13 as shown in FIG. On the other hand, it becomes shorter (R ′). As described above, when the rotation axis of the driving sphere 13 does not face the horizontal direction, the distance from the rotation axis to the ball contact point on the running surface, that is, the effective radius is not fixed, and the control system becomes complicated.
When the driving sphere 13 rotates in an arbitrary direction, the relationship between the rotational speed of the rotor 24 and the rotor 24 is as shown in FIG. In other words, the radii R ′ and R ″ of the circle parallel to the rotation direction of the driving sphere 13 and passing through the contact point between the rotor 24 and the driving sphere 13 indicate that the rotation direction of the sphere coincides with the rotation direction of the rotor 24. Except for this, it becomes shorter than the radius R of the driving sphere 13.

In addition, when the rotation axis of the driving sphere 13 does not face the horizontal direction with respect to the floor surface, there are the following problems.
Hereinafter, the driving sphere 13 and the rotating shaft 26 of the rotor 24 will be used and described with reference to FIGS. Here, FIG. 7A is an explanatory diagram when the height position of the axis of the rotation shaft 26 of the rotor 24 is the same height position as the rotation center of the driving sphere 13, and FIG. These are explanatory drawings when the height position of the axis of the rotation shaft 26 is set to a position below the rotation center of the driving sphere 13. 7C to 7E are explanatory diagrams when the driving sphere 13 is rotated in the positional relationship of FIG. 7A, and FIGS. 7F to 7H are FIGS. It is explanatory drawing when the driving sphere 13 is rotated in the positional relationship of B).

When the driving sphere 13 is rotated so that the rotational axis (axial center) of the driving sphere 13 and the rotational axis 26 of the rotor 24 are parallel to each other as shown in FIGS. The rotor 24 can rotate the rotation direction of the driving sphere 13 in a direction opposite to the rotation direction of the rotor 24 without rubbing the surface of the driving sphere 13.
Further, when the rotation axis of the driving sphere 13 is shifted 90 degrees in plan view from FIGS. 7C and 7F due to the rotation of the other rotor 24 and the contact with the floor surface 17, FIG. ), The driving sphere 13 rotates around the position where the driving sphere 13 and the rotor 24 are in point contact. For this reason, the rotor 24 rubs the surface of the driving sphere 13 by point contact, but the surface of the driving sphere 13 is damaged by the frictional force at this time, and the rotation direction of the driving sphere 13 is the target direction. The risk of swaying can be reduced.

On the other hand, in FIG. 7G, since the rotation directions of the driving sphere 13 and the rotor 24 are orthogonal, the surface of the driving sphere 13 is rubbed without the rotor 24 rotating. For this reason, the surface of the driving sphere 13 may be damaged by the frictional force at this time, and the rotation direction of the driving sphere 13 may deviate from the intended direction.
In addition, by the rotation of each rotor 24 and the contact with the floor surface 17, the rotational axis of the driving sphere 13 is changed between FIGS. 7C and 7D and FIGS. In the case of shifting by 45 degrees in plan view from the rotation axis of FIGS. 7C and 7F, in FIG. 7E, the rotor 24 can rotate without rubbing the surface of the driving sphere 13. In FIG. 7H, the rotor 24 rubs against the surface of the driving sphere 13 while rotating.

From the above, it is necessary to set the height position of the axis of the rotation shaft 26 of each rotor 24 to the same height position as the rotation center of each driving sphere 11 to 13. The same applies to the rotors 30 and 31.
Further, by arranging each rotor 24 on a line connecting the rotation centers of the driving sphere 12 and the driving sphere 13 in plan view, the driving spheres 12 and 13 can stably sandwich the rotor 24 from both sides. it can.
Thereby, it is possible to prevent displacement between the driving spheres 12 and 13 and the rotor 24.
In addition, when the height position of the axial center of the rotating shaft 26 of each rotor 24 is set to the same height position as the rotation center of each driving sphere 11 to 13, the driving sphere 11 to 13 is rotated by the rotation of each rotor 24. May come off the carriage 19.

For this reason, it is preferable to provide a fall prevention cover (not shown) at the bottom of the carriage. This drop prevention cover is formed with an opening having an inner diameter smaller than the diameter of each of the driving spheres 11 to 13 in accordance with the arrangement position of each of the driving spheres 11 to 13. Accordingly, the lower portions of the driving spheres 11 to 13 are protruded from the openings, respectively, and even when the driving spheres 11 to 13 are rotated by the driving means 14 to 16, the dropping from the carriage 19 can be prevented. In addition, by attaching a soft brush-like object (brush member) so as to lightly contact each of the driving spheres 11 to 13 toward the inside of the opening, dust and dirt of each of the driving spheres 11 to 13 can be removed. It can be removed simultaneously with the traveling of the carriage 19.
Moreover, you may use the ball-type caster which can rotate to the omnidirectional which contacts the surrounding surface of each driving sphere 11-13 for the positioning of each driving sphere 11-13 in the horizontal direction. In this case, since the ball type caster rotates without being affected by the place of contact with the driving spheres 11 to 13, the driving spheres 11 to 13 can be prevented from being detached from the carriage 19.
As described above, by configuring the sphere-driven omnidirectional moving device 10, the moving device 10 can be moved in all directions.

Next, a method for controlling the traveling direction of the sphere-driven omnidirectional moving device 10 will be described.
First, as shown in FIG. 8A, a coordinate system fixed to the moving device 10 is defined.
Here, three driving spheres are arranged as spheres 1 to 3 at respective vertices of the triangle, and the origin O is set inside the triangle. The y axis is taken in the direction of the ground contact point of the sphere 1 and the x axis is taken in the direction perpendicular to the y axis. The number of each sphere is given counterclockwise from the sphere 1. The subscript i (i = 1, 2, 3) indicates the number of the sphere. Further, let Li (m) be the distance from the origin O to each sphere i.

Next, a coordinate system for each sphere i is defined as shown in FIG.
Here, the contact point of each sphere i is defined as a point Oi, and the y _i axis is taken in the direction from the origin O to Oi, and the x _i axis is taken in the direction orthogonal thereto. The rotation angle of each spherical coordinate system from the moving mechanism coordinate system is defined as θi (rad).
The coordinates of the contact point Oi of each sphere i in the movement mechanism coordinate system can be expressed by the distance Li from the origin O, the angle θi formed by the y-axis and O-Oi (counterclockwise is positive).

FIG. 9A shows the speed of the moving device 10.
Here, the x-direction component of the translation speed at the origin O of the moving device 10 is v _x (m / s), the y-direction component is v _y (m / s), and the counterclockwise rotation angular velocity (number of revolutions) around the origin O is set. ) Is r (rad / s). At this time, the rotational angular velocity component r is orthogonal to the direction from the origin O to the point Oi. That is, the rotational angular velocity component r is parallel to the _xi axis.
Here, in each sphere ground point Oi, the speed of the _{x i} axis component of the mobile device _{10 w xi (m / s)} , when the _{y i} axis component and _w yi (m / s), the following relationship It holds.

Here, when the velocity vector at the origin O of the moving apparatus 10 is v = (v _x , v _y , r) ^T , the following relationship is established between v and the component vector of each axis.

FIG. 9B shows velocity components w _xi (m / s) and w _yi (m / s) at the sphere contact point, respectively.
The angular velocity of the rotor driving sphere 1 and sphere 2 is λ ₁ (rad / s), the angular velocity of the rotor driving sphere 2 and sphere 3 is λ ₂ (rad / s), and the rotor driving sphere 3 and sphere 1 Assume that the angular velocity is λ ₃ (rad / s). Here, λi is positive in the clockwise direction when viewed from the outside of the moving device 10.
If the effective radius of the rotor is δi (m), the angular velocity of the rotor and the velocity component δiλi in the direction perpendicular to the rotation axis of the rotor at the sphere contact point can be decomposed into the x _i component and the y _i component. A relationship is established.

Further, the following relationship is established from the equations (3) and (5).

Here, in Equation (7), the following is set.

Thereby, the translational movement speed and rotation speed of the moving apparatus 10 are calculated | required as follows from the rotation angular velocity of a rotor.

Conversely, the rotational angular velocity of the rotor is determined from the translation speed and the rotational speed of the moving device 10 as follows.

In particular, when the center of each sphere is arranged at the vertex position of an equilateral triangle, that is, δ = δ ₁ = δ ₂ = δ ₃ , θ ₁ = 0, θ ₂ = 2/3 · π, θ ₃ = 4/3. When π, L = L ₁ = L ₂ = L ₃ , and ξi = ψi = 1/6 · π, the above P and U are simplified as follows.

The rotational angular velocities of the rotors can be derived from the relationship shown above, so that the drive control of the moving device 10 can be performed by programming them.
Considering the movement of the moving device 10, the movement of the moving device 10 is defined by the equations of motion around the x-axis direction, the y-axis direction, and the origin O, and the acceleration is at the contact point with the running surface of each sphere. Caused by frictional forces. At this time, the following relationship holds.

However, the mass of the moving device 10 is M (kg), and the moment of inertia around the origin O is Iv (kgm ² ). Note that Fxi and Fyi are frictional forces due to the contact between the sphere and the floor, and are represented by the product of the normal force and the friction coefficient.
By programming the above relationship, the acceleration of the mobile device 10 can be controlled.

Using the method shown above, the rotor 24 for rotating the driving spheres 11 to 13 is rotated by the driving motor 25 by the control unit, and the moving device 10 is operated. Here, a typical movement of the moving device 10 will be described below assuming that the driving sphere 11 is located on the front side, the driving sphere 12 is located on the right side, and the driving sphere 13 is located on the left side. .
First, the case where the moving apparatus 10 is made to travel straight forward is described.
As shown in FIG. 10A, in a state where the rotation of the rotor 24 that is simultaneously in contact with the driving spheres 12 and 13 located on the left and right sides is stopped, the driving device 10 located on the front side in the plan view of the moving device 10 The two rotors 24 in contact with the sphere 11 for rotation are rotated at the same rotational speed from the sphere 11 for driving to the sphere 12 for driving and the sphere 13 for driving.
As a result, the driving sphere 11 rotates in the direction of moving the moving device 10 forward, and the other driving spheres 12 and 13 rotate around the contact point of the rotor 24 that contacts each other. You can go straight ahead. In the case where the moving device 10 is allowed to travel straight in the rearward direction (the direction opposite to the moving direction shown in FIG. 10A) without changing the rotational direction of the two rotors 24 that are in contact with the driving sphere 11, What is necessary is just to make it the opposite direction to the above-mentioned direction.

Next, the case where the moving apparatus 10 is made to travel straight in the left direction will be described.
As shown in FIG. 10B, when the moving device 10 is viewed in plan, the rotor 24 that is in contact with the driving spheres 12 and 13 located on the left and right sides at the same time is moved from the driving sphere 13 to the driving sphere 12. The other two rotors 24 that are rotated and in contact with the driving sphere 11 located on the front side are moved from the driving sphere 13 side to the driving sphere 11 side and from the driving sphere 11 side to the driving sphere 12 side. Rotate each. The other two rotors 24 that are in contact with the driving sphere 11 located on the front side rotate at the same rotational speed.
Thereby, the moving device 10 can travel straight in the left direction. When the moving device 10 travels straight in the right direction (the direction opposite to the moving direction shown in FIG. 10B), the rotation direction of each rotor 24 may be set to the opposite direction to the above-described direction.

The case where the moving apparatus 10 is made to travel straight ahead in the diagonally left direction will be described.
As shown in FIG. 10C, the three rotors 24 are rotated so that the driving spheres 11 to 13 coincide with the moving direction of the moving device 10. Specifically, in plan view of the moving device 10, the two rotors 24 that are in contact with the driving sphere 12 located on the right side are rotated from the driving sphere 11 side and the driving sphere 13 side to the driving sphere 12 side. The other rotor 24 is rotated from the driving sphere 11 side to the driving sphere 13 side. At this time, the rotational speeds of the two rotors 24 that are in contact with the driving sphere 12 located on the right side differ depending on the moving direction of the moving device 10.
Thereby, the moving apparatus 10 can travel straight ahead in the diagonally left direction. In addition, what is necessary is just to make rotation of each rotor 24 into the opposite direction to the above-mentioned direction, when making the moving apparatus 10 drive straight ahead in the diagonally right backward direction (the direction opposite to the moving direction shown in FIG. 10C). Further, when the moving device 10 travels straight forward in the diagonally right direction, the rotational speeds of the two rotors 24 that contact the driving sphere 11 are reversed, and the rotor 24 that contacts the other driving spheres 12 and 13 simultaneously. What is necessary is just to make rotation into the reverse direction to the above-mentioned direction.

Finally, a case where the moving device 10 is turned counterclockwise will be described.
As shown in FIG. 10D, all the rotors 24 are rotated in the same direction and at the same rotational speed. FIG. 10D shows a state in the middle of turning.
Thereby, the moving apparatus 10 can be turned counterclockwise. In addition, what is necessary is just to make rotation of each rotor 24 into the opposite direction to the above-mentioned direction, when turning the moving apparatus 10 clockwise.
As described above, in the sphere driven omnidirectional moving device 10, all of the driving spheres 11 to 13 are rotated in the same direction as the moving direction of the moving device 10. For this reason, the manufacturing cost can be reduced, and the sphere-driven omnidirectional movement device 10 that is not easily affected by the unevenness of the floor surface and has high stability during traveling can be provided.

As described above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the configuration described in the above embodiment, and the matters described in the scope of claims. Other embodiments and modifications conceivable within the scope are also included. For example, a case where the sphere-driven omnidirectional moving device of the present invention is configured by combining some or all of the above-described embodiments and modifications is also included in the scope of the right of the present invention.
In the above embodiment, the case where the three driving spheres are arranged at the vertex positions of the equilateral triangle in plan view has been described. However, the present invention is not limited to this, and may be an isosceles triangle, for example. .

In the above embodiment, the case where the driving means is constituted by the rotor and the driving motor, and the case where the driving means is constituted by the rotor, the power transmission belt, and the driving motor have been described. However, the present invention is not limited to this. For example, one or two of the driving means may be configured by a rotor and a driving motor, and the other may be configured by a rotor, a power transmission belt, and a driving motor.
Further, the sphere-driven omnidirectional moving device using three driving spheres can be provided as one set, and can be provided in one set or a plurality of sets of two or more sets, depending on the scale of the cart. Further, one set of sphere-driven omnidirectional moving devices may be arranged at the center of gravity of the carriage, and an auxiliary caster may be attached around the carriage.

(A), (B) is the plane sectional view of the spherical body drive type omnidirectional movement device concerning one embodiment of the present invention, respectively, and a partially notched front view. (A), (B) is the plane sectional view of the spherical body drive type omnidirectional movement device concerning a modification, and a partial notch front view. It is explanatory drawing which shows the frictional force of the spherical body for a drive, and a rotor. (A), (B) is explanatory drawing which shows the arrangement position of the rotor with respect to the driving sphere, respectively. (A), (B) is explanatory drawing which shows the relationship between the rotating shaft of a driving sphere, and an effective radius, respectively. It is explanatory drawing which shows the relationship between the spherical body for a drive, and the rotational speed of a rotor. (A) is an explanatory view when the axis of the rotation shaft is at the same height position as the rotation center of the driving sphere, (B) is an explanatory view when the position is lower than the rotation center of the driving sphere, (C ) To (E) are explanatory diagrams when the driving sphere is rotated with the positional relationship of (A), and (F) to (H) are explanatory diagrams when the driving sphere is rotated with the positional relationship of (B). FIG. (A), (B) is explanatory drawing of the definition of the position coordinate of the sphere drive type omnidirectional movement apparatus which concerns on one embodiment of this invention, respectively, and the position coordinate of the drive sphere of the same sphere drive type omnidirectional movement apparatus It is explanatory drawing of a definition. (A), (B) is explanatory drawing of the speed of the same spherical body drive type omnidirectional movement apparatus, respectively, and explanatory drawing of the speed component of the driving sphere of the same spherical body drive type omnidirectional movement apparatus. (A)-(D) are explanatory drawings at the time of straight traveling in the forward direction of the same spherical body drive type omnidirectional moving device, explanatory diagrams at the time of straight traveling to the left, and at the time of straight traveling to the left diagonally forward It is explanatory drawing and explanatory drawing at the time of turning.

Explanation of symbols

10: Sphere-driven omnidirectional moving device, 11-13: Driving sphere, 14-16: Driving means, 17: Floor surface, 18: Mounting table, 19: Carriage, 20-22: Ball type caster for support, 23 : Lower surface, 24: Rotor, 25: Driving motor, 26: Rotating shaft, 27 to 29: Driving means, 30, 31: Rotor, 32: Power transmission belt, 33: Driving motor, 34, 35: Rotating shaft , 36: inner surface, 37: wheel caster

Claims (8)

It has three driving spheres of the same shape arranged at the apex position of the triangle in plan view, and three driving means for simultaneously rotating the driving spheres arranged adjacent to each other in the same direction. A sphere-driven omnidirectional moving device. 2. The sphere-driven omnidirectional movement device according to claim 1, wherein the triangle is a regular triangle. 3. The sphere-driven omnidirectional movement device according to claim 1, wherein the driving unit includes a rotor that simultaneously contacts a circumferential surface of the driving sphere arranged adjacent to the sphere, and the rotor. A spherically driven omnidirectional moving device comprising a driving motor for rotational driving. 3. The sphere-driven omnidirectional movement device according to claim 1, wherein the driving unit includes a rotor that contacts a peripheral surface of the driving sphere arranged adjacent to each other, and the two A sphere-driven omnidirectional movement device comprising a power transmission belt for connecting a rotor and a drive motor for rotationally driving one of the two rotors. 5. The sphere-driven omnidirectional movement device according to claim 1, wherein the driving sphere is positioned at the same height as the rotation center of the driving sphere for lateral positioning of the driving spheres. A sphere-driven omnidirectional movement device using a wheel-type caster that contacts a side surface of a sphere and makes the driving sphere rotatable in the vertical direction. 5. The sphere-driven omnidirectional movement device according to claim 1, wherein each of the driving spheres is rotatable in all directions in contact with a peripheral surface of the driving sphere for lateral positioning. A sphere-driven omnidirectional movement device characterized by using a ball-type caster. 7. The sphere-driven omnidirectional movement device according to claim 5, wherein each of the driving spheres has a drop prevention cover in which an opening is formed in accordance with an arrangement position of each of the driving spheres. Sphere-driven omnidirectional, characterized in that the lower part of each driving sphere protrudes from the opening and prevents the driving sphere from falling off the carriage. Mobile equipment. 8. The sphere-driven omnidirectional movement device according to claim 7, wherein a brush member that contacts the surface of each driving sphere is provided inside the opening of the drop-off prevention cover. A sphere-driven omnidirectional movement device.

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