JPS6033172A - Travelling and walking vehicle - Google Patents

Abstract

PURPOSE:To make the walking device of a wheel chair compact and light- weight, and as well to make it possible to ascend and descend stairs, by attaching, to the vehicle body of the wheel chair, more than 5 link legs each composed of more than five joints and provided with a wheel at its tread section, anc by providing two walking and travelling motors to the root section of each link leg. CONSTITUTION:More than five legs 2 through 7 each consisting of linkage provide at its tread section with a wheel and having more than 5 joints, are attached to a vehicle body 1, and two travelling and walking motors are provided to each leg. Upon travelling on a flat surface ground the legs 4, 5 are raised, and the control of speed and position is made in accordance with data from encoders disposed in the motors 14, 15. Upon ascending stairs the height and width of each step are measured when the stairs are identified by sensors, and the moving amounts of the legs 2 through 7 are computed in a central control unit. The motors are operated in association with the outputs of drive units so that the legs 2 through 7 carry out their walking operation. The sensors detect the angle made between a seat 17 and the gravitation, and therefore, motors for controlling the attitude of the seat, maintain the seat in its horizontal attitude.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a running/walking device having a stair climbing function that can be applied to a wheelchair or the like.

Various robots with the ability to ascend and descend stairs have been proposed, but these robots are used for work in unmanned factories and nuclear reactors, and are structurally very large, making it difficult to apply them to wheelchairs. There's a problem.

For example, wheelchairs equipped with crawlers are known, but when applied to wheelchairs, they are heavier and have a larger turning radius than regular wheelchairs. It cannot be used inside or inside a house.

The present invention has been made in view of the above circumstances, and its purpose is to provide a running/walking device that is lightweight, has a compact overall structure, and is equipped with a stair climbing function that can be applied to a wheelchair. be.

That is, in the present invention, the vehicle body is equipped with five or more legs consisting of links of five or more sections each having a wheel on the ground-contacting part, and two motors for walking action are arranged on the root side of each leg. , and the walking action effecting moke is fixed to the vehicle body.

Further, the vehicle body is further provided with a swingable support platform on which a person or an object is placed, and an attitude control mechanism is provided between the support platform and the vehicle body to maintain the support platform horizontally. It is said that

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing an example of applying the present invention to a wheelchair;
FIG. 2 is a partially cutaway side view, and FIG. 3 is a partially cutaway partially sectional view.

The wheelchair of this embodiment is equipped with six legs and can go up and down stairs by walking. It is also equipped with flat ground driving and attitude control functions.

That is, at the front, rear, and center positions on both sides of the vehicle body 1,
Legs 2 to 7 are each equipped. These legs 2 to 7 are composed of five-section links, and the ground contact part has wheels 8.
~13 are provided.

The rear legs 6 and 7 each have a motor 14 for running action.
, 15 are provided, and the motor 1 for these running actions
4 and 15 drive the rear wheels 12 and 13.

When the vehicle is traveling on flat ground or stopped, the vehicle body 1 is supported by the front legs 2 and 3 and the rear legs 6 and 7, as shown in FIG.

The central legs 4 and 5 are apart from the ground when running on level ground or when stopped, and touch the ground to support the vehicle body 1 when going up and down stairs.

Each of the legs 2 to 7 is driven by 12 motors 16 for walking action fixed to the vehicle body 1, and is used to go up and down stairs and to go over steps.

In addition, a support stand 18 supporting the seat 17 is provided on the vehicle body 1.
is equipped with a swingable motor 19 for posture control.
The seat 17 is always held horizontally with respect to gravity by a posture control mechanism 21 using an internal gear 20.

The above is the overall overview. Next, the mechanisms of the legs 2 to 7 will be explained in detail.

Legs 2 to 7 are composed of five-section links, as described above. As shown in FIG. 3, two motors 16 for walking motion are disposed at the base of each of the legs 2 to 7 attached to both sides of the vehicle body l. These motors 16 are each fixed to the inner surface of the side plate 1a of the vehicle body 1.

A harmonic drive gear 22 is provided at one end of the motor 16 directly connected to the drive shaft 16a, and a brake 23 and an encoder 24 are provided at the other end similarly directly connected to the drive shaft (not shown). ing.

The output shaft 22a of the harmonic drive gear 22 is connected to the base of the legs 2 to 7, and when the motor 16 rotates, this rotation is decelerated and the base links 2a, 2 serve as the roots.
b~7a, 7b, and the links 2a, 2b~7
a and 7b rotate. As a result, the ground contact portions, which are the tips of the legs 2 to 7, draw trajectories as shown in FIG. this leg 2
The permissible rotation angle of each of the joints 7 to 7 is smaller than that of a pure five-bar link, so the range of the trajectory drawn by the ground contact part is narrower, but it is sufficient for going up and down stairs.

As shown in FIG. 3, the center legs 4 and 5 are combined with each other so that their constituent links 4a, 5a to 4d, and 5d do not restrict their rotation.
It can operate both forward and backward.

These central legs 4 and 5 play an auxiliary role when going up and down stairs.

For the front legs 2, 3 and the rear legs 6, 7, the link 2 that constitutes them
a, 3a to 2d, 3d, 6a, 7a to 6d, and 7d may hit each other, so the motors can only operate in one area partitioned by the line connecting the two motors 16.

The aforementioned brake 23 has a built-in electromagnetic clutch mechanism, and is released only when the motor 16 is energized.
7 links are allowed to rotate. Normally, the elastic force of the spring is used to prevent the links of the legs 2 to 7 from rotating. Therefore, energy consumption can be suppressed and safety can be ensured.

Further, the encoder 24 detects the positions of the legs 2 to 7 from the rotation angle of the output shaft 22a. The front legs 2, 3 and the rear legs 6, 7 are provided with potentiometers (not shown) to recognize the absolute positions of the legs 2, 3, 6°7 at the time of starting. Since the central legs 4, 5 always return to a fixed position, there is no need to provide potentiometers.

Note that the absolute positions of the legs 2 to 7 can be detected using only the potentiometers, but the accuracy cannot be obtained, so in this embodiment, the encoder 24 and the potentiometers are used. is detected by an encoder.

The wheels 8, 9 provided on the front legs 2, 3 are links 2cl,
It is configured so that it can also rotate around the 3d axis.

The links constituting the legs 2 to 7 may have five or more sections, but if the links have five sections as in this embodiment, the stairs can be moved up and down smoothly.

In the method of the present invention, in which two motors 16 are disposed on the base sides of the legs 2 to 7, and these motors 16 are fixed to the vehicle body 1, each joint part as shown in FIG. Compared to a method in which the motors 16 are arranged, when an equal load is applied to the tip of the leg, the load on each motor is smaller, and even a small motor can support a large load. Therefore, according to the present invention, the total weight of the vehicle body can be reduced, and the motor can be made smaller, which is a synergistic effect.

Although not shown, the motors 14 and 15 are provided with encoders, and the wheels 8 and 9 are provided with brakes.

Next, the posture control mechanism 21 of the seat 17 will be explained in detail.

A support arm 26 is swingably provided in the center of the bottom plate 1b of the vehicle body 1 via a bin 25. and,
The above-mentioned support stand 18 is fixed to the upper end of this support arm 26.

The above-described motor 19 for attitude control is fixed to the side surface of the upper end of the support arm 26 (see FIG. 4). A worm 27 is provided on the drive shaft 19a of this motor 19. Further, a transmission shaft 29 is provided between the upper end of the support arm 26 and an L bracket 28 provided on the lower surface of one end of the support base 18, parallel to the bottom plate 1b. A worm wheel 30 that meshes with the worm 27 is provided at the end of the transmission shaft 29 on the support arm 26 side, and a worm wheel 30 is provided at the end of the transmission shaft 29 on the L bracket 28 side, which is fixed at the upper end position of the inner surface of the side plate 1a. A pinion 31 meshing with the aforementioned internal gear 20
is provided.

When the motor 19 rotates, the rotation is transmitted to the transmission shaft 29 through the engagement between the worm 27 and the worm wheel 30.
The pinion 31 moves along the internal gear 20 while rotating. As a result, the seat 17 is rotated relative to the vehicle body 1 and maintained in a highly horizontal state.

This posture control mechanism 21 can eliminate the risk of overturning even if the vehicle body 1 is tilted when going up and down stairs or climbing over steps.

That is, as shown in FIGS. 7a and 7b, the entire center of gravity does not shift backward, so there is no risk of falling. As shown in Figure C, seat 1. ) If the seat 17 is fixed to the vehicle body 1, the entire center of gravity will shift rearward, which will limit the ground contact range of the legs, and there is a risk of the vehicle falling backwards.

In this embodiment, a distance is provided between the motor 19 and the pinion 31 that is rotated by the motor 19 and moves along the internal gear 20, and the motor 19 is moved slightly in line with the inclination of the vehicle body 1. The structure is such that the motor 19 is rotated in steps, so the load on the motor 19 is small, and even a small motor can be used satisfactorily.

Next, the control device 32 that controls the legs 2 to 7 and the posture control mechanism 21 described above will be explained in detail.

The control device 32 includes a central control section 33, a motor drive unit 34, and a sensor unit 35.

The central control unit 33 is composed of a 16-bit microcomputer, and controls the motors 14, 15, 16, 1 based on the information obtained from the sensor unit 35 and the current state of the wheelchair.
9 is calculated and a command is given to the motor drive unit 34.

The motor drive unit 34 includes a control section 36 and a motor drive section 37 each consisting of an 8-bit microcomputer. ts, 16, and 19, and digitally controls the motors 14, 15, 16, and 19 in response to commands from the central control unit 33. The information given at this time is velocity and displacement. Position information of the legs 2 to 7 is input to the control unit 36 from the encoder 24 and a potentiometer (not shown).

The sensor unit 35 includes a control section 38 consisting of an 8-bit microcomputer, a sensor control section 39, and a sensor 40.
It is composed of. The control unit 38 converts and processes signals from the sensor 40. In addition to the aforementioned encoder 24, potentiometer (not shown), and encoders (not shown) provided for the motors 14 and 15, the sensor 40 also detects the load state of the motors 14, 15, 16, and 19 from the motor current value. There are sensors for detecting obstacles, an ultrasonic sensor for recognizing obstacles such as stairs and steps, and an inclined needle for detecting the angle θ (see FIG. 11) between the seat 17 and the direction of gravity. Based on the information from these sensors 40, each monitor 14,1
5, 16, and 19 are controlled. In addition, the ultrasonic sensor is
In addition to recognizing stairs, etc., it also measures the distance to the stairs and the height and depth of each step.

As described above, processing efficiency can be improved by dividing the control device 32 into units and arranging them hierarchically using a plurality of micro convenience stores.

9 and 10 are flowcharts showing the operation of the control device 32. FIG.

When the power is turned on, the system is initialized and the absolute positions of the legs 2, 3, 6.7 are detected by the potentiometers. Note that since the starting position of the legs 4.5 is constant, position detection is not required.

When running on flat ground, the legs 4 and 5 are lifted off the ground.

Encoders provided on motors 14 and 15 (not shown)
Speed and position control is performed based on this information.

When going up stairs, the sensor 40 recognizes the stairs and the vehicle runs on level ground until the entrance to the stairs. Then, the sensor 40 measures the height and width (back 1 te) of each step. Based on this measured value, the central control unit 33 calculates the amount of movement of the legs 2 to 7, and this calculated value is used by the motor drive unit 34.
is output to. As a result, each motor 16 operates,
Legs 2 to 7 perform a walking motion, and during this walking motion, the condition of the stairs is detected in detail by the sensor 40, and the amount of movement is corrected based on this information. This operation is repeated until you reach the top of the stairs.

Also, when going up the stairs, the sensor 40 detects the seat 1.
7 and the direction of gravity (see FIG. 11) is detected. Then, this angle θ is compared with the set value φ (approximately 0°), and if it is not equal to 1, the output of the motor 19 is calculated according to the difference with the set value φ, and the motor 19 is operated. . This operation is repeated until you reach the top of the stairs. Thereby, the seat 17 is always maintained horizontally even if the vehicle body 1 is tilted. When the vehicle climbs up the stairs and starts traveling on flat ground, the rotation direction of the motor 19 is opposite to that when the vehicle is climbing the stairs.

Next, the movements of the legs 2 to 7 when going up and down stairs will be described in detail with reference to FIGS. 12a-f.

In the present invention, whether going up or down stairs or walking on flat ground, the same algorithm is used in principle to
I am trying to make 7 moves.

This means that if the leg of the perpendicular line drawn from the center of gravity of the device in the direction of gravity is included in the polygon formed by the wheels in contact with the ground,
This is based on the fact that in a static state, it is stable and will never fall over.

Therefore, when moving up and down stairs, the vehicle body 1 is always supported with four or more legs.

That is, as shown in FIG. 12a, legs 2, 3° 5.6
．． 7 to support the vehicle body 1, lift the legs 4, and proceed to step 4.
Move to step 3. Next, as shown in the figure, the leg 6 is moved from step 5 to step 4. Thereafter, as shown in C%f of the figure, legs 5, 7, and 2.3 are moved to the next step in this order.

To summarize this operation, as shown in the table below, the legs supporting the vehicle body 1 are not stationary;
The vehicle body 1 is controlled to move one step in one cycle (a=f in FIG. 12).

When going down the stairs, do the opposite of what you do when going up.

When running on flat ground, the turning radius can be reduced by operating the motors 16 of the front legs 2, 3 and rear legs 6, 7 to reduce the distance between the front wheels 8, 9 and the rear wheels 12, 13. It is.

Furthermore, if one of the driving action motors 14, 15 is controlled to rotate in the forward direction and the other in the reverse direction, the front wheels 8.9 can rotate around the axes of the links 2d, 3d, thereby reducing the turning radius. , and allows quick turning movements.

As in the present embodiment, the legs 6 and 7 are provided with a running action motor 14,
15, the load applied to the motors 14 and 15 can be reduced. In other words, the driving action motors 14, 15
You can use a small one as a. Therefore, the weight of the entire vehicle body can be reduced, and no burden is placed on the walking action motor 16. Furthermore, unlike the case where the vehicle body 1 is equipped with a complicated rotation transmission mechanism, the configuration is simple.

Although not shown as a power source, a battery is used. The battery is mounted on the vehicle body 1 or on the legs 2 to 7. Note that the control device 32 may be driven by a solar battery.

In addition, although the case where six legs were equipped was shown in the said Example, it is sufficient if there are at least five legs. In this way, the vehicle main body l can be supported by the four legs when going up and down stairs.

The traveling/walking device of the present invention can be used not only as a wheelchair but also as a working robot in an unmanned factory or a nuclear reactor.

As explained above, according to the present invention, since the vehicle body is equipped with five or more legs each consisting of five or more links, the weight can be reduced compared to one using crawlers. At the same time, the whole can be made compact, and the turning radius can be reduced to improve maneuverability.

In addition, two walking action motors are installed at the base of each leg, and the motors are fixed to the vehicle body.
The load acting on each motor is small, so the synergistic effect of reducing the size of the motor and reducing the total weight of the vehicle body is achieved.

Furthermore, since the support base is maintained horizontally by the posture control mechanism, there is no risk of falling when going up or down stairs, and it is safe.

Therefore, according to the present invention, it is safe even when applied to a wheelchair, and can be used on general roads and in houses.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a side view, FIG. 2 is a partially cutaway side view, and FIG. 3 is a partially cutaway partially sectional view. FIG. 4 is a partial plan view showing the meshing state of the worm and the worm wheel, FIG. 5 is a diagram showing the locus of movement of the legs, and FIG. 6 is an explanatory diagram showing a comparative example.
7a-c are explanatory diagrams explaining the effects of the posture control mechanism, FIG. 8 is a block diagram of the control device, FIGS. 9 and 10 are flowcharts showing the operation of the control device, and FIG. An explanatory diagram of the angle formed by the direction of gravity and the direction of gravity, Figure 12 a w
f is an explanatory diagram of the movement up and down the stairs. 1...Car body, 2-7...Legs, 14
．． 15...Motor for running action, 16...
- Walking action motor, 17... Support stand, posture control mechanism [19... Posture control motor, 26...
... Support arm, 27 ... Worm, 29
......Transmission shaft, 30...Worm wheel, 31...Pinion, 20...Internal gear], 32...Control device. Patent applicant Hiroyasu Funa Kubo Agent Hideo Takino 12th prisoner

Claims (1)

[Scope of Claims] (11) The vehicle body is equipped with five or more legs consisting of links of five or more sections with wheels provided at the ground-contacting part, and each leg is equipped with two motors for walking motion on the root side. A running/walking device characterized in that the walking action motor is fixed to the body of the vehicle. In addition, two walking action motors are arranged on the base side of each leg, and the walking action motors are fixed to the vehicle body, and a support base for placing a person or object on the vehicle body is provided. 1. A running/walking device that is swingably equipped and includes an attitude control mechanism that maintains the support platform horizontally between the support platform and the vehicle body.