JP3183466B2 - Walking robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

 [Object of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a walking robot which moves by driving a leg.

[0002]

2. Description of the Related Art In recent years, a walking robot having a plurality of legs and moving by controlling the movement of these legs has been actively researched. Walking robots are characterized by being able to move without being affected by any irregularities on the road surface, and have the advantage of being much more stable than moving means using wheels. There is. Therefore, it is expected as a means of transporting people and goods in the future.

For such a walking robot, walking control according to the number of legs has been conventionally studied. In particular, in walking control with a small number of legs, such as two legs or four legs, there is a restriction on the relationship between the position of the center of gravity of the robot and the driven leg, so advanced control such as moving the center of gravity of the robot is also required. Have been.

However, in any of the walking robots, the movement of the legs is not related to Tomovic 'or McGhh.
The following form proposed by ee is still used. That is, as shown in FIGS. 22 (a) to (i), at least two joints are provided on the legs, and the walking operation is realized by controlling the rotation angles of these joints in a coordinated manner.

In FIGS. 1A to 1C, the "kick leg" operation is performed by rotating only the first joint 51 clockwise while fixing the second joint 52. FIG. Next, (d) to (f) of FIG.
In the example, the "up leg" operation is performed by rotating the first joint 51 counterclockwise and rotating the second joint 52 clockwise. In FIGS. 8G to 8I, the "lowering leg" operation is performed by rotating the second joint 52 counterclockwise while fixing the first joint 51.

As described above, in the case of FIG. 22, the legs are driven by repeating "fixation", "clockwise rotation", and "counterclockwise rotation" for each of the joints 51 and 52, and the robot moves.

That is, as shown schematically in FIG. 23, the legs of the walking robot are required to have a drive stroke and a return stroke that combine vertical movement and forward / backward movement of the legs.

[0008]

However, in the above-mentioned conventional walking robot, since at least two joints are required for one foot, the rotation angles of these joints must be controlled in a coordinated manner. For example, the operation as shown in FIG. 22 cannot be realized, and the robot does not walk.

Accordingly, an object of the present invention is to provide a walking robot capable of realizing a drive stroke and a return stroke without performing cooperative control of a plurality of joints, thereby easily achieving a walking operation. [Configuration of the Invention]

[0010]

In order to achieve the above object, according to the present invention, there is provided a cylindrical elastic body having a plurality of pressure chambers internally separated by a partition extending in an axial direction; Having a base to which a plurality of bodies are fixed, and adjusting the pressure of the pressure chamber so that the cylindrical elastic body bends in the traveling direction;
A walking robot that performs a walking motion by continuously performing elongation deformation, bending to the opposite side of the traveling direction, and returning to the original state.

[0011]

According to the above arrangement, a large pressure is applied to an arbitrary pressure chamber of the walking means so that the pressure chamber expands. That is, the walking means can be curved in a predetermined direction by the difference in pressure applied to each pressure chamber of the walking means.

When the pressure in each pressure chamber is increased as a whole, the walking means is extended, and when the pressure is reduced, the walking means is reduced. That is, the walking means can be expanded or contracted in any direction by the total amount of pressure applied to the walking means.

[0013] Therefore, only by applying pressure to the pressure chamber, the legs have the freedom required for walking. Therefore, the robot can be easily walked without requiring complicated control such as cooperative control of two joints.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view of a walking robot showing a first embodiment of the present invention, FIG. 2 is a side view of the walking robot,
FIG. 3 is a plan view of the walking robot.

The walking robot 1 according to the present embodiment has six legs (walking means) 2 (2a to 2f). These three legs 2 a to 2 f are arranged on the side of the base 3 by three each. Then, the outside of a sealing portion 10 (described later) formed on the upper portions of the legs 2a to 2f is fixed to the base 3 so as to be sandwiched by fixing members 4 (4a to 4f). Here, as the fixing method, screwing is selected so that the legs 2a to 2f are detachable. Further, here, the legs 2a to 2f are fixed so as to be perpendicular to the base 3, but the legs 2a, 2b, 2c and the legs 2d, 2e, 2f move away from each other as they approach the tip. As described above, it may be fixed obliquely with respect to the base 3.

FIG. 3 shows a fixed state of the legs 2a to 2f with respect to the base 3. Each of the legs 2a to 2f has a partition wall 5 (described later) inside thereof, as shown by a chain line in FIG.
Are formed to extend in the axial direction. Also,
As shown in the figure, the legs 2a to 2f are fixed so that the surface of the partition wall 5 is orthogonal to the traveling direction of the walking robot 1.

The position of the center of gravity of the walking robot 1 is shown in FIG.
Is designed to coincide with the center of the base, that is, the centroid position.

Next, the legs 2a to 2f will be described in detail.

As shown in an exploded perspective view of FIG. 5, the leg portion 2 includes a cylindrical elastic body 8 forming an outer wall, a tip sealing portion 9, a root sealing portion 10, a tube 11 (11a, 11b) and a tip portion. It is composed of a member 12. As can be seen from the figure, the cylindrical elastic body 8 is composed of two unit cylindrical elastic bodies 13 having the same shape.
(13a, 13b) are integrally formed by bonding them in parallel in the axial direction. For this reason, the elastic partition 5 extends in the axial direction of the cylindrical elastic body 8 by the bonded portion, and two pressure chambers 14 and 15 are formed by the elastic partition 5. As shown in FIGS. 5 and 6, the unit cylindrical elastic bodies 13a and 13b cover the fibers 17 wound spirally at close intervals with respect to the direction perpendicular to the drawing, with silicon-rubber as an elastic material. It is formed. For this reason, since the cylindrical elastic body 8 is formed of an anisotropic elastic material formed of a composite of the fiber 17 and rubber, the direction in which the longitudinal elastic modulus is small substantially coincides with the axial direction 18 of the cylindrical elastic body 8. It is easy to stretch in the direction 18. Further, in the direction 19 orthogonal to the axial direction 18, the fibers 17 make it difficult to expand due to a large longitudinal elastic coefficient.

The front end sealing portion 9 is made of metal or the like, and is formed in the unit cylindrical elastic bodies 13a and 13b.
One end of each of the fan-shaped upper lids 9a and 9b for sealing the first and fourth seals 4 and 15 is inserted into and adhered to the unitary tubular elastic bodies 13a and 13b.

The root sealing portion 10 is formed by inserting fan-shaped lower lids 10a and 10b similar to the tip sealing portion 9 and one ends of the lower lids 10a and 10b into the unit cylindrical elastic bodies 13a and 13b. It is configured by bonding and sealing.

Also, the tube 11 is attached to the lower lids 10a and 10b.
Insertion holes 20a and 20b into which a and 11b are inserted and fixed are provided, respectively. The tubes 11a and 11b are hermetically fixed to the insertion holes 20a and 20b with an adhesive. tube
The other end of each of 11a and 11b is connected to a pressure control device (not shown) (for example, an air source, a pressure control valve, and a computer for controlling them) so that the pressure of the working fluid can be freely adjusted. ing. Although not shown here, the periphery of the two unit cylindrical elastic bodies 13a and 13b adhered is further covered with silicone rubber.

Further, a tip member 12 made of silicone rubber is adhered to the tip of the tip sealing portion 9 of the tubular elastic body 8. The tip member 12 has a substantially spherical shape. The tip member 12 may be processed to have a relatively large surface friction coefficient.

The operation of the leg 2 having the above configuration will be described. For example, assume that the working fluid is fed from the tube 11a to increase the pressure in the pressure chamber 14. As a result, as shown in FIG. 4, the pressure chamber 14 extends in the axial direction, and the cylindrical elastic body 8 is curved in the direction A to be in a state indicated by a chain line.

When the working fluid is fed from the tube 11b to increase the pressure in the pressure chamber 15, the pressure chamber 15 extends in the axial direction, and the cylindrical elastic body 8 bends in the direction B opposite to the direction A.

In this way, the combination of the pressures applied to the two pressure chambers 14 and 15 allows the tubular elastic body 8 to bend in two directions. If the pressures in the two pressure chambers 14 and 15 are equally increased, the cylindrical elastic body 8 can be straightened in the axial direction 18.

As described above, by controlling the pressures of the two pressure chambers 14 and 15 using the characteristics of the anisotropic elastic material,
The operation of bending and expanding and contracting is simultaneously realized in the cylindrical elastic body 8.

The cylindrical elastic body 8 is made of a unitary cylindrical elastic body 13a, 13b wound with fibers and covered with silicone rubber, but is not wound with fibers. After the unit cylindrical elastic body is bonded, the fiber may be entirely wound and then coated with silicone rubber. Further, the distal end member 12 may be directly joined to the tubular elastic body 8 without using the distal end sealing portion 9. Further, the root sealing portion 10 may be integrally formed of silicone rubber instead of metal.

If the walking robot 1 uses the cylindrical elastic body 8 having such characteristics as the legs 2, a walking cycle as shown in FIG. 11 is realized. Note that FIG. 2 is a view of the leg portion 2 of the walking robot 1 as viewed from the side, and advances leftward in the drawing.

First, the pressure applied to each of the pressure chambers 14 and 15 is set such that the leg 2 has an axial length as shown in FIG.

Next, a predetermined amount of pressure is applied so that the pressure in the pressure chamber 14 on the side opposite to the traveling direction becomes large, thereby obtaining the state shown in FIG.
The leg 2 is curved so as to move the tip member 12 in the traveling direction. At this time, since the leg 2 also undergoes elongation deformation, the length in the axial direction (the length in the direction perpendicular to the base 3) is increased.

Next, by pressurizing the pressure in the pressure chamber 15 in the traveling direction by a predetermined amount, as shown in FIG. In this state, only elongation deformation occurs. At this time, the axial length of the leg 2 is the longest in the walking cycle because the pressure in each of the pressure chambers 14 and 15 is the maximum.

Finally, the pressure in the pressure chamber 14 on the side opposite to the traveling direction is reduced by a predetermined amount so that the pressure in the pressure chamber 14 becomes small.
As shown in (d), the leg 2 is curved so as to move the tip member 12 in the direction opposite to the traveling direction. Leg 2 at this time
The length in the axial direction is shorter than that in the state shown in FIG.

Then, the pressure in the pressure chamber 15 is reduced by a predetermined amount to return to the state shown in FIG. That is,
By repeating the above-described deformation of the leg 2, the walking cycle of FIG. 23 is continuously performed.

By appropriately combining the above-described walking cycle with each leg of the walking robot 1, the walking robot 1 can perform a stable walking operation. FIGS. 13 (a) and 13 (b) schematically show the walking robot 1 viewed from above. In the figures, circles and circles indicate legs driven in the same walking cycle. ing. Here, G indicates the position of the center of gravity of the walking robot 1.

Here, it is first assumed that the leg ○ is in the state of FIG. 11 (a) and the leg ● is in the state of FIG. 11 (c). At this time, three legs ●
Supports the base 3, while the legs ○ are floating.

Next, when the leg ○ changes to the state shown in FIG.
The leg ● changes to the state shown in (d). Therefore, all the legs are in a state of supporting the base 3.

Next, when the leg ○ changes to the state shown in FIG.
The leg ● changes to the state shown in (a). At this time, since the leg portion ○ changes like kicking the ground, the walking robot 1 moves by a predetermined amount in the traveling direction as a whole.

Finally, when the leg ○ changes to the state shown in FIG. 4D, the leg 変 化 changes to the state shown in FIG. At this time, since the leg ○ continuously changes to kick the ground, the walking robot 1 further moves by a predetermined amount in the traveling direction as a whole.

As described above, in the process shown in FIGS. 11 (b) to 11 (d), since the tip member 12 changes like kicking the ground, the walking robot 1 moves in the traveling direction. In the process of FIGS. 11 (d) and 11 (b), the leg 2 moves the tip member 12 to the position of the kick leg again while floating.

That is, as shown in FIG. 23, generally, a walking stroke requires a drive stroke and a return stroke, and in order to achieve these, it is absolutely necessary to move the legs up and down and back and forth. That is, at least two joints are required for the legs. However, according to the present invention, by using the cylindrical elastic body, the vertical movement and the forward and backward movement of the legs can be realized at the same time without requiring two joints. Therefore, it is not necessary to control the two joints as in the related art, and a complicated walking motion can be easily realized simply by controlling the pressure applied to the pressure chamber.

To change the drive stroke and the return stroke of the walking robot 1 having such a configuration, the pressure applied to each pressure chamber may be changed. In other words, the greater the applied pressure, the greater the amount of bending and elongation, so that the drive stroke and the return stroke can be increased. Further, by attaching cylindrical elastic bodies having different diameters and axial lengths, the drive stroke and the return stroke can be varied.

Next, a second embodiment of the present invention will be described. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

The walking robot according to the second embodiment has the structure shown in FIG.
Has the same appearance as the walking robot of the first embodiment shown in FIG. However, the difference is that a leg 2 having a structure as shown in FIGS. 9 and 10 is used.

That is, each of the legs 2a to 2f has three partition walls 5, 6, 7 formed therein so as to extend in the axial direction. These partition walls 5, 6, 7 are approximately 120 °
Formed at intervals, of which one partition 5 is:
As shown by a chain line in FIG. 7, all the legs are fixed so as to face in the same direction (left direction in FIG. 7).

With respect to the leg 2 having such a configuration,
The operation will be described with reference to FIG. For example, it is assumed that the working fluid is sent from the tube 11a to increase the pressure in the pressure chamber 14. By doing so, the pressure chamber 14 extends in the axial direction, and the cylindrical elastic body 8 is curved in the direction A to be in a state shown by a chain line.
In this state, if the pressure in the pressure chamber 16 is further increased through the tube 11c, the cylindrical elastic body 8 will bend in the C direction. In this way, the combination of the pressures applied to the three pressure chambers 14, 15, 16 allows the tubular elastic body 8 to bend in any direction. Further, if the pressures of the three pressure chambers 14, 15, 16 are increased equally, the cylindrical elastic body 8 can be straightened in the axial direction 18.

Further, if the walking robot 1 uses the cylindrical elastic body 8 having such characteristics as the leg 2, a walking cycle as shown in FIG. 12 is realized as in the first embodiment.

First, the pressure applied to each of the pressure chambers 14, 15, 16 is as follows:
In the initial state, the leg 2 is set to have an axial length as shown in FIG.

Next, a predetermined amount of pressure is applied so that the pressure in the pressure chamber 14 on the side opposite to the traveling direction is increased, thereby obtaining the state shown in FIG.
The leg 2 is curved so as to move the tip member 12 in the traveling direction. At this time, since the leg 2 also undergoes elongation deformation, the length in the axial direction (the length in the direction perpendicular to the base 3) is increased.

Next, by increasing the pressure in the pressure chambers 15, 16 in the traveling direction by a predetermined amount, as shown in FIG. And it is in a state of only elongation deformation. At this time, the length of the leg 2 in the axial direction is the longest in the walking cycle because the pressure in each of the pressure chambers 14, 15, and 16 is maximum.

Finally, the pressure in the pressure chamber 14 on the side opposite to the traveling direction is reduced by a predetermined amount so that the pressure in the pressure chamber 14 becomes small.
As shown in (d), the leg 2 is curved so as to move the tip member (d) in the direction opposite to the traveling direction. At this time, the axial length of the leg 2 is reduced by the pressure in the pressure chamber 14,
It is shorter than the state of FIG.

Then, the pressure in the pressure chambers 15 and 16 is reduced by a predetermined amount to return to the state shown in FIG. That is, by repeating the above-described deformation of the leg 2, FIG.
Is continuously performed.

These walking cycles are realized by digitally controlling the pressure using, for example, an electromagnetic switching valve (on-off valve) as a pressure control valve.

Although the same walking cycle as that of the first embodiment is realized by applying the same pressure to the pressure chambers 15 and 16 in the above-described illustration, for example, the same pressure is applied to the pressure chambers 14 and 16. If the pressure is controlled to be applied, the traveling direction of the walking robot 1 can be inclined by 60 °. Thus, by arbitrarily selecting the pressure chamber, the moving direction of the robot can be changed in units of 60 °. Of course, in this case as well, it is only necessary to perform digital control using an electromagnetic switching valve as the pressure control valve.

Further, if a pressure proportional valve is used as the pressure control valve, the pressure can be digitally controlled.
As a result, the pressure applied to each pressure chamber of the leg 2 can be continuously changed, and the leg 2 can be bent in an arbitrary direction. In such a case, the moving direction of the robot is not limited to the above-mentioned 60 ° unit, and the robot can walk in any direction.

When the leg 2 according to the second embodiment is used, the following remarkable effects are obtained.

That is, since the leg according to the first embodiment has two pressure chambers, there is a feature that the control law for walking is extremely simple, while the partition wall is perpendicular to the traveling direction of the robot. Therefore, depending on the load applied to the robot, the legs may buckle. However, in the second embodiment, since the partition walls are arranged so as to be supported at three points against a load applied from the axial direction of the leg portion, a static stable structure is obtained, and there is no fear of buckling. Therefore, according to the second embodiment, the walking robot according to the first embodiment can withstand a larger load than the walking robot according to the first embodiment, and is excellent in terms of transport performance.

FIGS. 14 to 18 show the cross-sectional structure of the leg 2 which can withstand a relatively large load. The number of partitions is not necessarily three,
Or four or more. Also, the number and shape of the pressure chambers can be arbitrarily selected. In short, any structure may be used as long as it is supported at three or more points so that it can be a static stable structure against a load applied from the axial direction of the leg.
In particular, in the case of the leg 2 having a structure as shown in FIG. 18, the number of the pressure chambers is two, so that the pressure control becomes easy, and at the same time, the partition wall is supported at three points against an axial load. Since it is arranged, it is also a static stable structure.

Next, a third embodiment of the present invention will be described.

FIG. 19 is a perspective view of a walking robot showing a third embodiment of the present invention. FIG. 20 is a side view of the walking robot.
FIG. 21 is a plan view of the walking robot.

The walking robot 100 according to this embodiment has four legs 2a to 2d (the same as the above-mentioned legs). These legs 2a to 2d are arranged such that the tip members 12a to 12d form a square with respect to the base 3. The outside of the sealing portion 10 formed on the upper portions of the legs 2a to 2d is fixed to the base 3 so as to be sandwiched by fixing members 4 (4a to 4d). Here, as the fixing method, screwing is also selected so that the legs 2a to 2d are detachable.

Although the legs 2a to 2d are fixed at right angles to the base 3 here, the legs 2a to 2d are inclined with respect to the base 3 so that the legs are separated from each other as they approach the tip. It may be fixed to. Further, each of the tip members 12a to 12d may form an arbitrary square instead of forming a square.

FIG. 21 shows a fixed state of the legs 2a to 2d with respect to the base 3. Here, the case where the legs shown in FIG. 9 are used is described. The legs 2a to 2d are fixed so that the extension lines of the respective partition walls 5 intersect at the position of the center of gravity of the base 3 of the walking robot 100 (here, coincides with the centroid).

In order for the four-legged walking robot 100 having such a configuration to realize a walking cycle, unlike the case of the six-legged walking robot 1 described above, since the partition walls 5 are arranged radially, each pressure chamber 14 , 15, and 16 must be controlled according to the following equations.

[0066]

(Equation 1) That is, the movement of the distal end member 12 depends on the bending direction θ _i of the leg 2,
Axial length Z _i, is determined by the parameter K _i representing the bending amount.

For example, when _Ki is 0, the leg 2 only expands and contracts in the axial direction without bending. The legs 2 as K _i is increased greatly (deep) curved.

[0068] For this reason, in the case of moving from the state of FIG. 21 walking robot 100 in the X axis direction, ⁰ theta _i
Is changed to 0 and only Z _i and K _i are changed as described below, whereby a walking cycle as shown in FIG. 12 can be realized.

That is, the curved state of the leg 2 is shown in FIG.
In order to change to (d), _Ki is gradually reduced.
To return 12 from (d) again to (b) may be gradually increased K _i. On the other hand, FIG.
To change to (c), set Z _i to a constant value (except 0)
And To return from FIG. 12 (c) to (a) again, set Z _i to 0
And it is sufficient.

Accordingly, the pressure in each of the pressure chambers 14, 15, and 16 is controlled so as to continuously perform such a series of operations, so that the center of gravity of the walking robot 100 comes inside the grounded leg. If the four legs 2 are driven in an appropriate order with an appropriate phase difference, a stable walking operation can be realized.

If pressure control is performed so that the time required for displacement from FIG. 12 (b) to (d) becomes three times or more the time required for displacement from FIG. 12 (d) to (b). Particularly, a stable walking motion is realized. This is at least 3 out of 4 legs
This is because the legs are grounded at the same time.

[0072] Moreover, by changing only the ⁰ theta _i, it is also possible to control the traveling direction of the walking robot 100 in an arbitrary direction.

Further, the legs 2a to 2d of the walking robot 100
When the pressure chambers 14, 15, 16 are arranged in one direction like the walking robot 1, the walking robot 100 can be walked by controlling the pressure of the legs 2 in the walking robot 1 as shown in FIG. It can also be done. In this case,
Each phase of the twelve walking cycles must be provided to each leg 2a-2d in an appropriate order. (For example, in FIG. 12 (a), leg 2b
12 (b), FIG. 12 (c) for the leg 2c, and FIG. 12 (d) for the leg 2d. Therefore, the walking robot 100 can be walked by simple pressure control that digitally controls the electromagnetic switching valve.

Although the embodiments of the present invention have been described above, the present invention is not limited to a six-legged walking robot or a four-legged walking robot, but can be applied to a two-legged or five-legged or more walking robot. The same operation and effect can be obtained.

[0075]

As described above, according to the walking robot of the present invention, the degree of freedom required for walking can be realized on the legs only by applying pressure to the pressure chamber. Therefore, the robot can be easily walked without complicated control.

[Brief description of the drawings]

FIG. 1 is a perspective view of a walking robot according to a first embodiment of the present invention.

FIG. 2 is a side view of the walking robot according to the first embodiment of the present invention.

FIG. 3 is a plan view of the walking robot according to the first embodiment of the present invention.

FIG. 4 is an overall perspective view of a leg of the walking robot according to the first embodiment of the present invention.

FIG. 5 is an exploded perspective view of the leg shown in FIG. 4;

FIG. 6 is a sectional view of the leg shown in FIG. 4;

FIG. 7 is a plan view of a walking robot according to a second embodiment of the present invention.

FIG. 8 is an overall perspective view of a leg of a walking robot according to a second embodiment of the present invention.

FIG. 9 is an exploded perspective view of the leg shown in FIG. 8;

FIG. 10 is a sectional view of the leg shown in FIG. 8;

FIG. 11 is a view showing a walking cycle.

FIG. 12 is a diagram showing a walking cycle.

FIG. 13 is a schematic diagram illustrating an example of a combination of walking cycles of a walking robot.

FIG. 14 is a sectional view showing a modified example of the leg.

FIG. 15 is a cross-sectional view showing a modification of the leg.

FIG. 16 is a sectional view showing a modification of the leg.

FIG. 17 is a cross-sectional view showing a modification of the leg.

FIG. 18 is a sectional view showing a modified example of the leg.

FIG. 19 is a perspective view of a walking robot according to a third embodiment of the present invention.

FIG. 20 is a side view of a walking robot according to a third embodiment of the present invention.

FIG. 21 is a plan view of a walking robot according to a third embodiment of the present invention.

FIG. 22 is a view showing a walking form of a general walking robot.

FIG. 23 is a diagram showing a walking cycle necessary for a walking robot.

[Explanation of symbols]

 1,100: walking robot 2: leg (walking means) 3: base 5, 6, 7 ... partition wall 8: cylindrical elastic body 11: tube 13: unit cylindrical elastic body 14, 15, 16, pressure chamber

Continuation of the front page (56) References JP-A-2-131884 (JP, A) JP-A-1-247809 (JP, A) JP-A-51-147589 (JP, U) JP-A-49-36303 (JP, A) , Y1) (58) Field surveyed (Int. Cl. ⁷ , DB name) B25J 5/00

Claims (1)

(57) [Claims] 1. A cylindrical elastic body whose inside is separated into a plurality of pressure chambers by a partition wall extending in an axial direction, and a base to which the plurality of cylindrical elastic bodies are fixed. The walking operation is performed by adjusting the pressure so that the cylindrical elastic body continuously performs bending in the traveling direction, elongation deformation, bending in the opposite direction to the traveling direction, and return to the original state. A walking robot characterized by the following.