JP2001191704A - Wheel for omnidirectionally moving car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize accurate odometry and stable travel. SOLUTION: This wheel for an omnidirectionally moving car used for the omnidirectionally moving car moving in all directions on a plane, is provided with a first barrel-shaped free roller having an external shape having curvature made coincident with curvature of a circle and having a swelling shaft directional central part and a second barrel-shaped free roller forming a space in an area of inner diameter side both end parts, having an external shape having curvature made coincident with curvature of a circle, having a swelling shaft directional central part and having a diameter larger than the first barrel-shaped free roller, and the first barrel-shaped free roller and the second barrel-shaped free roller are mutually alternately arranged so that a part of the first barrel- shaped free roller is positioned in a space formed in the second barrel-shaped free roller, the shaft direction crosses at a right angle to a driving shaft and the external shape forms the circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an omnidirectional vehicle wheel, and more particularly, to a robot, an AGV (automatic guided vehicle), an automobile or other level terrain mechanism moving on a plane in all directions. The present invention relates to an omnidirectional vehicle wheel suitable for use in an omnidirectional vehicle.

[0002]

2. Description of the Related Art In general, a mobile robot traveling on a flat surface is required to have a stable running. In addition, when a mobile robot behaves in a small environment or works in cooperation with another robot,
It is desirable to be able to freely control the posture and position of the robot in all directions, and many studies have been conducted on robots capable of moving in all directions.

That is, an omnidirectional mobile robot traveling on a plane has a total of three degrees of freedom, two degrees of translation for movement in the X-axis direction and movement in the Y-axis direction, and one degree of freedom for rotation about the Z-axis. Freedom of athletic performance must be possible.

By the way, the wheels of such an omni-directional mobile vehicle such as an omni-directional mobile robot, that is, wheels for an omni-directional mobile vehicle, have friction with a ground contact surface such as a floor surface in a specific direction like ordinary wheels. While generating driving force by
In many cases, a wheel that does not generate a force (releasing the load) in a direction orthogonal to the specific direction is used.

[0005] Until now, a free roller (a "free roller" is a roller that idles passively like a caster around an axis) around a shaft is used to constitute an omnidirectional vehicle wheel. Various mechanisms have been proposed.

That is, as an omnidirectional vehicle wheel using a free roller, for example, one type of free roller is formed in a double row, or a barrel-shaped wheel having a central portion protruding along the axial direction. A combination of a barrel-shaped free roller provided with a cylindrical free roller and a cylindrical free roller is known.

However, in a wheel for an omnidirectional vehicle in which one type of free roller is formed in a double row, the contact point of the wheel for an omnidirectional vehicle on a ground surface such as a floor surface is determined by the omnidirectional vehicle. Changes in the axial direction with the rotation of the wheel, the tread (distance between wheels) of the omnidirectional vehicle changes, and odometry (estimation of the distance and direction of movement) becomes inaccurate. There was a problem.

Further, in the wheel for an omnidirectional vehicle constituted by combining a barrel-shaped free roller and a cylindrical free roller, there is a portion where the outer shape of the omnidirectional vehicle wheel does not coincide with a circle. When the omnidirectional vehicle wheel is rotated around the axis of the omnidirectional vehicle wheel, a grounding surface such as a floor on which the omnidirectional vehicle wheel contacts the ground and the omnidirectional vehicle wheel Distance is not always constant, and stable running cannot be performed.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned various problems of the prior art. The tread of the omnidirectional vehicle can be maintained constant by preventing the ground contact point of the omnidirectional vehicle wheel from changing in the axial direction with the rotation of the omnidirectional vehicle wheel. It is an object of the present invention to provide an omnidirectional vehicle wheel capable of realizing an accurate odometry.

It is another object of the present invention to make the outer shape of the omnidirectional vehicle wheel very close to a circle so that the omnidirectional vehicle wheel is positioned around the axis of the omnidirectional vehicle wheel. When the is rotated, the distance between the ground contact surface, such as the floor, on which the omnidirectional vehicle wheels touch the ground, and the omnidirectional vehicle wheels can be always kept constant, realizing stable running. It is an object of the present invention to provide an omnidirectional vehicle wheel.

[0011]

In order to achieve the above object, the omnidirectional vehicle wheel according to the present invention has two types of barrel-shaped free rollers having different diameters, that is, a large diameter and a small diameter. Are alternately arranged to form a cavity in which the shaft and bearing of the large-diameter barrel-shaped free roller and a part of the small-diameter barrel-shaped free roller are located inside the large-diameter barrel-shaped free roller. In addition, by setting the curvature of each barrel-shaped free roller so as to match the curvature of the circle, an omnidirectional moving vehicle wheel composed of a single row of barrel-shaped free rollers whose outer shape is very close to a circle is configured. It was made.

Therefore, according to the omnidirectional vehicle wheel according to the present invention, as described above, the omnidirectional vehicle wheel can be constituted by a single row of barrel-shaped free rollers, so that contact with a floor surface or the like can be achieved. The ground contact point of the omnidirectional vehicle wheel on the ground is always on the outline of a single row of barrel-shaped free rollers,
Since the ground contact point does not change in the axial direction with the rotation of the wheel for the omnidirectional vehicle, the tread of the omnidirectional vehicle can be kept constant, and accurate odometry can be obtained. become.

According to the omnidirectional vehicle wheel according to the present invention, as described above, the outer shape of the omnidirectional vehicle wheel is very close to a circle. When the wheels for the moving vehicle are rotated, the distance between the grounding surface such as the floor on which the wheels for the omnidirectional vehicle touches the ground and the wheels for the omnidirectional vehicle can always be kept constant. It becomes possible to perform the running that was done.

That is, according to the first aspect of the present invention, in an omnidirectional vehicle wheel used for an omnidirectional vehicle that moves in all directions on a plane, a curvature whose outer shape matches the curvature of a circle is provided. A first barrel-shaped free roller having an axially central portion bulging out, and a shaft formed with voids in both end regions on the inner diameter side and having an outer shape matching the curvature of the circle. A second barrel-shaped free roller having a diameter larger than that of the first barrel-shaped free roller, the center of which is bulged in the direction, and the first barrel-shaped free roller and the second barrel-shaped free roller Are arranged so that a part of the first barrel-shaped free roller is located in the space formed in the second barrel-shaped free roller, and the axial direction is orthogonal to the drive shaft and Are arranged alternately with each other to form a circumference Than it is.

According to a second aspect of the present invention, there is provided an omnidirectional vehicle wheel used for an omnidirectional vehicle that moves in all directions on a plane, such that a drive shaft is orthogonal to a central portion. A plate-shaped member disposed, a U-shaped arm that opens toward the outer radial side of the plate-shaped member and whose opening direction is orthogonal to the drive shaft, and protrudes from the center of the arm; A plurality of supporting members having a mounting portion formed and arranged on the outer peripheral edge portion of the plate-like member via the mounting portion; and the arm of the supporting member being orthogonal to the drive shaft. And a first support shaft rotatably supported by the first support shaft and having a curvature whose outer shape matches the curvature of a circle and whose central portion in the axial direction swells. A barrel-shaped free roller, the arm of one of the support members adjacent to each other, and the other A second shaft arranged to be perpendicular to the drive shaft between the arms of the support member,
In addition to being rotatably supported by the second support shaft, voids are formed in the regions at both ends on the inner diameter side, and the central portion in the axial direction bulges with a curvature whose outer shape matches the curvature of the circle. And a second barrel-shaped free roller having a diameter larger than that of the first barrel-shaped free roller, wherein the first barrel-shaped free roller and the second barrel-shaped free roller are connected to the second barrel-shaped free roller.
The first space in the empty space formed in the barrel-shaped free roller of
Are arranged alternately with each other so that a part of the barrel-shaped free rollers are positioned, the axial direction is orthogonal to the drive shaft, and the outer shape forms a circumference.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an omnidirectional vehicle wheel according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a front view of an embodiment of an omnidirectional vehicle wheel according to the present invention, FIG. 2 is a side view of FIG. 1, and FIG. A in FIG.
FIG. 4 is an enlarged cross-sectional view of a part, and FIG. 4 is a structural explanatory view showing a part of the structure of FIG. 2 by a skeleton.

The wheel 10 for an omnidirectional vehicle includes a circular plate-shaped member 12 in which a drive shaft 11 penetrates at a central portion so as to cross at right angles, and is fixedly disposed. Opening toward the side and the opening direction is the drive shaft 1
And a U-shaped arm 14a orthogonal to the arm 1 and the arm 1
A support member 14 having a mounting portion 14b protrudingly formed at the center of the support member 4a, and six support members 14 arranged at equal intervals via the mounting portion 14b on the outer peripheral edge portion of the plate-shaped member 12;
A first support shaft 16 disposed between the U-shaped arms 14a so as to be orthogonal to the drive shaft 11, and a first barrel rotatably supported on the first support shaft 16 via a bearing 18. A second support shaft 2 disposed orthogonal to the drive shaft 11 between the mold free roller 20 and a shoulder 14c of one arm 14a and a shoulder 14c of the other arm 14a adjacent to each other.
2 and a second barrel-type free roller 26 rotatably supported on a second support shaft 22 via a bearing 24.

Therefore, the first barrel-shaped free roller 20 and the second barrel-shaped free roller 26 are arranged so that the axial direction is orthogonal to the drive shaft 11.

Further, the first barrel-type free roller 20 and the second
The barrel-shaped free rollers 26 have a curvature whose outer shape matches the curvature of the circle, and are formed in a barrel-shaped shape in which the central portion in the axial direction is bulged, and are arranged alternately with each other so as to form a circumference. Is what is done.

Here, the first barrel-type free roller 20 comprises an inner diameter side member 20a made of metal located on the inner diameter side and an outer diameter side member 20b made of rubber located on the outer diameter side. The mold free roller 26 is composed of an inner diameter side member 26a made of metal located on the inner diameter side and an outer diameter side member 26b made of rubber located on the outer diameter side.

The first barrel type free roller 20 and the second barrel type
The barrel-shaped free roller 26 is formed such that the first barrel-shaped free roller 20 is longer in the axial direction than the second barrel-shaped free roller 26, while the barrel-shaped free roller 26 is Are formed to be larger in diameter in the radial direction than the first barrel-type free roller 20.

That is, the length of the first barrel-shaped free roller 20 in the axial direction is “L1”, the length of the first barrel-shaped free roller 20 in the radial direction is “R1”, and the second barrel-shaped free roller 26 is Is set to be such that L1> L2 and R1 <R2 are satisfied, assuming that the length in the axial direction is “L2” and the length in the radial direction of the second barrel-shaped free roller 26 is “R2”.

The second barrel-shaped free roller 26 locks the bearing 24 at a central portion along the axial direction of the inner diameter side member 26a, and is supported by the second support shaft 22 via the bearing 24. Except for the central portion where the bearing 24 is locked, the region at both ends is a hollow space 26c. That is, the space 26c is formed in the region of both ends on the inner diameter side of the second barrel-shaped free roller 26.

Then, as described above, the first barrel-shaped free roller 20 and the second barrel-shaped free roller 26 have a “R1
Since the length in the radial direction is set so as to satisfy <R2 ”, the support member 14, the first support shaft 16, the bearing 18, and the first barrel are provided in the space 26c of the second barrel-type free roller 26. It can accommodate a portion of the various members of the mold free roller 20 that is located near the shoulder 14c of the support member 14.

Further, the curvature of the first barrel-shaped free roller 20 and the curvature of the second barrel-shaped free roller 26 are different from those of the first barrel-shaped free roller 26 as shown in FIGS. Locus on the outermost diameter side when assembling the mold free roller 20 and the second barrel free roller 26, that is,
The outer shape has a curvature that matches the circle.

The dimensions of L1, L2, R1, R2, etc., are determined by setting the diameter D of the omnidirectional vehicle wheel 10 to 200 mm.
mm, for example, “L1 = 59 mm”, “R1 =
30 mm "," L2 = 40 mm "," R2 = 45 mm "
However, it goes without saying that the dimensions of these members are appropriately changed and set according to the diameter D of the omnidirectional vehicle wheel 10.

In the above configuration, in order to assemble the omnidirectional vehicle wheel 10, the support member 14 and the first Two units are formed by assembling the support shaft 16, the bearing 18, the first barrel-type free roller 20, the second support shaft 22, the bearing 24, and the second barrel-type free roller 26.

The two units each having three support members 14 to which the respective members are assembled are integrally assembled while fixing the mounting portion 14b of each support member 14 to the outer peripheral edge portion of the plate member 12. Things.

The omnidirectional vehicle wheel 10 assembled as described above has a very circular outer shape, and therefore is omnidirectional around the drive shaft 11 of the omnidirectional vehicle wheel 10. When the moving vehicle wheel 10 is rotated, it is possible to always maintain a constant distance between the omnidirectional moving vehicle wheel 10 and a ground contact surface such as a floor on which the omnidirectional moving vehicle wheel 10 grounds, A stable running can be performed.

The omnidirectional vehicle wheel 10 is constructed by combining a first barrel-shaped free roller 20 and a second barrel-shaped free roller 26 in a single row in the axial direction of the drive shaft 11. Therefore, the ground contact point of the omnidirectional vehicle wheel 10 on the ground surface such as the floor surface is always on the circumference of the outer shape of the omnidirectional vehicle wheel 10 and the omnidirectional vehicle wheel 1
Since the ground contact point does not change in the axial direction with the rotation of 0, the tread of the omnidirectional vehicle to which the omnidirectional vehicle wheel 10 is attached can be kept constant,
Accurate odometry can be obtained.

The above embodiment may be appropriately modified as shown in the following (1) to (5).

(1) In the embodiment described above, the first barrel-type free roller 20 and the second barrel-type free roller 2
6, the inner diameter side members 20a and 26a are formed of metal, and the outer diameter side members 20b and 26b are formed of rubber. However, the material is not limited to this, and depending on the application, rubber, Needless to say, various materials such as plastic and metal can be appropriately selected and used.

(2) In the above embodiment, when forming the first barrel-shaped free roller 20 or the second barrel-shaped free roller 26, the inner diameter side member 20a (26a)
Needless to say, instead of being divided into the outer diameter side member 20b (26b) and the outer diameter side member 20b (26b), they may be integrally formed.

(3) In the above embodiment, the first barrel-shaped free roller 20 is formed to be longer in the axial direction than the second barrel-shaped free roller 26. However, the present invention is not limited to this. No, the first barrel-type free roller 20
And the second barrel-shaped free roller 26 may be formed so as to have the same axial length, and the second barrel-shaped free roller 26 may be formed more axially than the first barrel-shaped free roller 20. You may form so that it may become long.

(4) In the above embodiment, the first barrel-shaped free roller 20 and the second barrel-shaped free roller 2
6 are arranged respectively six times, but the present invention is not limited to this, and an arbitrary number (plurality) of the first barrel-shaped free rollers 20 and the second barrel-shaped free rollers 26 are respectively arranged. You may do so. In addition, as the diameter D of the omnidirectional vehicle wheel 10 increases, the first barrel-shaped free roller 20 constituting the omnidirectional vehicle wheel 10 increases.
It is preferable to increase the number of and the second barrel type free rollers 26.

(5) The above-described embodiment and the above-described modifications (1) to (4) may be appropriately combined.

[0038]

Since the present invention is constructed as described above, the contact point of the omnidirectional vehicle wheel on the ground surface such as the floor surface is changed in the axial direction together with the rotation of the omnidirectional vehicle wheel. , The tread of the omnidirectional vehicle can be maintained constant, and an accurate odometry can be realized.

Further, since the present invention is configured as described above, the outer shape of the omnidirectional vehicle wheel is very close to a circle, and the outer shape of the omnidirectional vehicle wheel is about the axis of the omnidirectional vehicle wheel. When the omnidirectional vehicle wheel is rotated, the distance between the omnidirectional vehicle wheel and the contact surface, such as the floor, on which the omnidirectional vehicle wheel contacts can always be kept constant. And an excellent effect that stable driving can be realized.

[Brief description of the drawings]

FIG. 1 is a front view of an example of an embodiment of an omnidirectional vehicle wheel according to the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is an enlarged sectional view of a portion A in FIG.

FIG. 4 is a configuration explanatory view showing a part of the configuration of FIG. 2 by a skeleton;

[Explanation of symbols]

 Reference Signs List 10 Wheel for omnidirectional vehicle 11 Drive shaft 12 Plate member 14 Support member 14a Arm portion 14b Attachment portion 14c Shoulder portion 16 First support shaft 18 Bearing 20 First barrel-type free roller 20a, 26a Inner diameter side member 20b, 26b Outside Diameter side member 22 Second support shaft 24 Bearing 26 Second barrel free roller 26c Empty space

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Isao Endo 2-1 Hirosawa, Wako-shi, Saitama Pref. RIKEN (72) Inventor Masatoshi Sato 12-201 Katsuhata Sakae, Saori-cho, Kaifu-gun, Aichi Prefecture

Claims (2)

[Claims] 1. An omnidirectional vehicle wheel used for an omnidirectional vehicle that moves in all directions on a plane, wherein the outer shape has a curvature that matches the curvature of a circle, and the first central portion in the axial direction swells. A barrel-shaped free roller, wherein the first barrel has a void formed in the region of both ends on the inner diameter side, and has a curvature whose outer shape matches the curvature of the circle, and the central portion in the axial direction swells. A second barrel-shaped free roller having a diameter larger than that of the mold-shaped free roller; and forming the first barrel-shaped free roller and the second barrel-shaped free roller on the second barrel-shaped free roller. The first barrel-shaped free rollers are partially located in the formed space, and are arranged alternately with each other such that the axial direction is orthogonal to the drive shaft and the outer shape forms a circumference. Wheels for omnidirectional vehicles. 2. An omnidirectional vehicle wheel for use in an omnidirectional vehicle that moves in all directions on a plane, comprising: a plate-shaped member having a drive shaft orthogonal to a central portion thereof; The plate-shaped member including a U-shaped arm portion that opens toward the outer radial direction and whose opening direction is perpendicular to the drive shaft, and a mounting portion that is formed to project from the center of the arm portion. A plurality of support members disposed at an outer peripheral edge portion of the support member via the mounting portion; a first support shaft disposed between the arm portions of the support member so as to be orthogonal to the drive shaft; A first barrel-shaped free roller that is rotatably supported by one spindle and has a curvature whose outer shape matches the curvature of a circle and whose central portion in the axial direction swells; and one of the supports adjacent to each other The drive shaft between the arm of the member and the arm of the other support member A second support shaft arranged orthogonally to the second support shaft, the second support shaft being rotatably supported by the second support shaft, and a space formed in both end portions on the inner diameter side; A second barrel-shaped free roller having a larger diameter than that of the first barrel-shaped free roller, the second barrel-shaped free roller having a larger diameter than the first barrel-shaped free roller, and having a central portion bulged with a curvature matched with the curvature; The roller and the second barrel-shaped free roller are positioned such that a part of the first barrel-shaped free roller is located in the space formed in the second barrel-shaped free roller, and the axial direction is An omnidirectional vehicle wheel which is orthogonal to the drive shaft and alternately arranged so that the outer shape forms a circumference.