CN1792698A - Robot with multi-mode wheels - Google Patents

Abstract

The invention relates to a multi-mode leg-wheel hybrid robot, which includes a body and four legs connected to the body, a rotary drive motor is installed at the end of each leg, and the roller constituting the feet is installed on the rotary drive motor through a one-way clutch on the reel. The legs of the robot can include thighs, calves and feet, and any leg has more than two revolving joints. The rotary drive motor can adopt a motor with self-locking function, and the one-way clutch is a one-way rolling bearing or a one-way rotating ratchet. The structure of each component in the present invention can be designed according to the routine, so it is easy to process and install. Through simple structural combination, the robot's sliding, rolling and crawling multiple motion modes are realized, and the adaptability of the robot to the terrain is improved. High energy efficiency ratio, easy control and reliable movement.

Description

Multi-modal leg-wheel hybrid robot

technical field

The invention relates to a multi-mode leg-wheel hybrid robot, which has the functions of sliding, rolling and crawling, and belongs to the technical field of robots.

Background technique

Existing mobile robots generally only have a single motion mode, such as rolling mobile robots, or crawling mobile robots. This kind of robot with a single motion mode has poor terrain adaptability, can only be used in specific environments, and cannot meet special applications such as expeditions. Therefore, people hope to have a robot that can have sliding, rolling and crawling motion modes at the same time, that is, select the sliding mode when on a smooth ice surface, select the high-speed rolling mode when on a flat and rough ground, and select the high-speed rolling mode when on a rough ice surface. Select crawl mode when on the ground.

Japan has made remarkable achievements in the development of multi-mode mobile robots. For example, Tokyo Institute of Technology has successfully developed a Roller-walker robot (Gen Endo, Shigeo Hirose. Study on roller-walker: multi-mode steering control and self-contained locomotion.ICRA '2000.San Francisco: CA, pp.2808-2814), which has four legs with a driven roller mounted on the end of each leg. Roller-walker has two motion modes of sliding and crawling. When each leg moves according to the predetermined track, the sliding friction force generated between the driven roller and the ground drives the robot to slide forward. When the roller is put down, the roller becomes Without feet, the robot can crawl forward. However, when the Roller-walker slides, the trajectory of the end of the leg is complex and difficult to control precisely. Moreover, part of the sliding friction forces cancel each other out, which reduces the sliding efficiency. and difficult to install. Due to the above reasons, the application of Roller-walker is subject to many restrictions. Therefore, it is necessary to design a new multi-modal mobile robot with simple structure and easy control.

Contents of the invention

The object of the present invention is to provide a multi-mode leg-wheel hybrid robot, which has a simple structure, is easy to control, and can realize multiple motion modes of sliding, rolling and crawling.

To achieve this purpose, the robot designed by the present invention includes a body and four legs connected to the body, a rotary drive motor is installed at the end of each leg, and the rollers forming the feet are installed on the rotating shaft of the rotary drive motor through a one-way clutch. superior.

In the present invention, the rotary drive motor may be a motor with a self-locking function.

The one-way clutch is a one-way rolling bearing or a one-way rotating ratchet.

Preferably, the body of the robot has a symmetrical structure, and the four legs are symmetrically distributed around the body, and the structure of each leg is exactly the same.

Preferably, the legs of the robot include a thigh, a calf and a foot, and any leg has a hip joint, a knee joint, an ankle joint and a rolling joint, the ankle joint rotates around the calf, and the other joints rotate around a horizontal axis.

Because the roller that forms pin is installed on the rotating shaft by one-way clutch. Therefore, when the rotary drive mechanism is not working, the roller is locked by the rotary shaft and cannot rotate in the direction where the rotating shaft and the one-way clutch are engaged, and the roller is not restricted by the rotating shaft and can rotate freely in the direction where the rotating shaft and the one-way clutch are separated; During work, the rotating shaft can drive the rollers to rotate together in the direction where the rotating shaft is engaged with the one-way clutch, and the rollers can rotate freely without being driven by the rotating shaft in the direction where the rotating shaft is separated from the one-way clutch.

The robot of the present invention can realize sliding, rolling and crawling motion modes. When sliding, by adjusting the direction of the four rollers, it can only roll forward, not backward. Through the robot's kicking stage, sliding stage, leg retracting stage and sliding stage again, the forward sliding is completed. By controlling the rotation angle of the ankle joint, the straight-line glide and turn glide of the robot can be realized. When rolling, the four rollers are controlled by their own independent drive motors to realize three driving modes: front-wheel drive rear-wheel driven, front-wheel driven rear-wheel drive and four-wheel drive, and control the rotation angle of the ankle joint It can realize the straight rolling and turning rolling of the robot. When the crawling mode is selected, by adjusting the direction of the four rollers, the two front leg rollers cannot roll forward, and the two rear leg rollers cannot roll backward, then the robot cannot roll forward and backward, and can only pass Crawling is movement. At this point, the four rollers of the robot are equivalent to the four feet of a quadruped reptile.

Compared with the prior art, the present invention has obvious effect. The structure of each component can be simply designed according to the routine, so it is easy to process and install; through a simple structure combination, the robot realizes various motion modes of sliding, rolling and crawling, which improves the adaptability of the robot to the terrain; In the sliding mode, the hybrid friction is all used as the driving force, and there is no problem of mutual cancellation, so the energy efficiency ratio is high; the planning and design of the three motion modes of the robot are simple, so it is easy to control and the motion is reliable.

Description of drawings

Fig. 1 is a structural diagram of a robot embodiment of the present invention.

In Fig. 1, 1 is the body of the robot, and 2 is the leg of the robot.

Fig. 2 is the structure of the leg in Fig. 1.

In Fig. 2, 3 is the thigh of the robot, 4 is the shank of the robot, 5 is the roller that constitutes the robot foot, 6 is the hip joint, 7 is the knee joint, 8 is the ankle joint, and 9 is the rolling joint at the end of the lower leg.

Fig. 3 is the installation structure of the roller in Fig. 2 .

Among Fig. 3, 5 is the roller that constitutes robot foot, and 10 is a rotary drive motor, and 11 is a motor rotating shaft, and 12 is a one-way clutch.

Fig. 4 is a diagram of the gliding process of the robot of the present invention.

Fig. 5 is a schematic diagram of the rolling of the robot of the present invention.

Fig. 6 is a crawling process diagram of the robot of the present invention.

Detailed ways

In order to better understand the technical solutions of the present invention, further description will be made below in conjunction with the accompanying drawings and embodiments.

Fig. 1 shows a kind of multi-pattern leg-wheel hybrid robot of the present invention, and it comprises body 1 and four legs 2, for simple design and easy analysis, described four legs 2 are symmetrically distributed around body 1 and the structure of each leg 2 exactly the same.

Of course, the four legs 2 can also be distributed asymmetrically around the body 1. Similarly, the structures of the four legs can be designed differently without affecting the implementation effect of the present invention, which is obvious to those skilled in the art.

Fig. 2 is the structure of any one leg in Fig. 1. Any leg 2 of the robot includes a thigh 3, a shank 4 and a roller 5 forming a foot. The upper part of the thigh 3 is rotatably connected with the body 1 to form a hip joint 6 that rotates around a horizontal axis, and a motor (not shown) that drives the thigh 3 to rotate is set at the hip joint 6 . The upper part of the lower leg 4 is rotationally connected with the lower part of the thigh 3 to form a knee joint 7 that rotates around a horizontal axis, and a motor (not shown) that drives the lower leg 4 to rotate is set at the knee joint 7 . The bottom of described shank 4 is also provided with the ankle joint 8 that rotates around shank 4, and described ankle joint 8 is provided with the motor (not shown) that drives roller 5 to rotate around the axis of shank 4. The roller 5 is connected with the end of the lower leg 4 to form a rolling joint 9 that rotates around a horizontal axis.

Equally, any one leg 2 also can only have thigh 3 and roller 5, perhaps has only shank 4 and roller 5, and this variation is just a kind of simple variation, is obvious to those skilled in the art, can not influence the implementation of the present invention Effect.

FIG. 3 is a schematic diagram of the connection structure between the roller 5 and the end of the lower leg 4 in FIG. 2 . A rotary drive motor 10 is installed at the end of the shank. The roller 5 is mounted on the rotating shaft 11 of the rotating electrical machine 10 through a one-way clutch 12 . The one-way clutch 12 is a one-way rolling bearing, and can also be other conventional one-way clutches 12, such as a one-way rotating ratchet or the like.

In order to effectively maintain the position of each joint, the driving motor at each joint is a motor with a self-locking function, such as using a worm gear for self-locking.

As shown in FIG. 3 , the one-way clutch 12 is a one-way rolling bearing, and the roller 5 constituting the foot is mounted on the motor shaft 11 through the one-way rolling bearing 12 . Therefore, when the motor 10 was not working, the direction roller 5 engaged with the one-way rolling bearing 12 at the rotating shaft 11 was locked by the rotating shaft 11 and could not rotate; Free rotation; when the motor 10 was working, the rotating shaft 11 could rotate with the driving roller 5 in the direction where the rotating shaft 11 was engaged with the one-way rolling bearing 12, and the rotating shaft 11 and the one-way rolling bearing 12 separated direction roller 5 was not driven by the rotating shaft 11, and could Turn freely.

It should be noted that the invention point of the present invention is: a rotary drive motor 10 is installed at the end of each leg, and a roller 5 is installed on the rotating shaft 11 of the rotary drive motor; Installed on the shaft 11 of the rotary drive motor. The above structure makes the rollers have three states: driven state (rotating freely in the direction where the rotating shaft of the rotating drive motor is separated from the one-way clutch), locked state (when the rotating driving motor is not working, the rotating shaft of the rotating driving motor Can not rotate in the direction engaged with the one-way clutch), and the driving state (when the rotary drive motor is working, it rotates with the rotating shaft in the direction in which the rotating shaft of the rotary drive motor is engaged with the one-way clutch). Therefore, the robot can realize various motion modes through the combination of the three states of the roller. This greatly simplifies the structure of the multi-mode mobile robot, and it is also easy to control. As for the structure of other parts of the leg, it can be any conventional design structure, and these changes can be easily imagined by those skilled in the art, so they will not be described in detail.

Briefly introduce various motion patterns of the robot of the present invention below:

【Sliding mode】

Figure 4 shows the gliding mode of the robot. Before gliding, at first adjust the direction of four rollers 5 by ankle joint 8, make four rollers 5 can only roll forward, can not roll backward. The gliding process of the robot can be divided into four stages: (1) kicking stage, when the front legs and the rear legs are swinging outwards, the front leg rollers 5 are free to roll forward, and the rear leg rollers 5 will cause the robot to move forward due to the inability to roll backwards. Sliding friction force moving forward; (2) sliding phase, the front and rear legs swing out to the predetermined maximum swing position (horizontal position) and then stop swinging, and the robot slides forward freely under the effect of inertia. (3) In the stage of retracting the legs, when the robot slides freely through a predetermined period of time, the front legs and the rear legs start to swing inwards from the maximum swing position. When swinging inwardly, the rear leg roller 5 freely rolls forward, and the front leg roller 5 can produce a sliding frictional force that makes the robot move forward because it cannot roll backward. (4) During the sliding phase, the front and rear legs swing inwards to the initial state and then stop swinging, and the robot slides forward freely under the action of inertia.

In addition, in the gliding phase, the straight-line gliding and turning gliding of the robot can be realized by controlling the rotation angle of the ankle joint 8 .

【Rolling mode】

FIG. 5 is a schematic diagram of a rolling mode. Since the four rollers 5 all have independent drive motors 10, the robot has the following three drive modes: front-wheel drive, rear-wheel driven; front-wheel driven, rear-wheel drive; four-wheel drive.

In the above three driving modes, the straight rolling and turning rolling of the robot can be realized by controlling the rotation angle of the ankle joint 8 .

【Crawl Mode】

Figure 6 shows the schematic diagram of the crawling process of the robot. When the crawling mode is selected, the robot first adjusts the directions of the four rollers 5 so that the two front leg rollers 5 cannot roll forward, and the two rear leg rollers 5 cannot roll backward. This makes the robot unable to roll forward and backward, and can only move by crawling. Now, the four rollers 5 of the robot are just equivalent to the four feet of the quadruped reptile.

As shown in FIG. 6 , step i represents the control process when each leg changes from state i to state i+1. Each step is described in detail below:

Step 1: Bend the right rear leg backwards and ensure that the right rear leg roller does not move in the front and rear direction, so that the center of gravity of the robot is shifted to the right rear side. At the same time, because the height of the right rear leg is lower than other legs, the robot body must The right rear side is tilted, which makes the left front part of the robot body tilt up and lifts the left front leg off the ground (as in state 2).

Step 2: After the left front leg is lifted off the ground, drive the hip joint of the left front leg to make the left front leg swing forward rapidly to the predetermined position (such as state 3), and the center of gravity of the robot will shift to the left front side accordingly, causing the robot body to move to the left front side Tilt, so the right rear portion of the robot body is upturned and the right hind leg is lifted off the ground (as state 3).

Step 3: Drive the hip joint and knee joint of the right rear leg to make the right rear leg swing forward to a predetermined position (such as state 4). At this time, the center of gravity of the robot will only move within the support surface formed by the left front, right front and left rear feet. The robot is in static equilibrium.

Step 4: Under the condition that the right front leg roller and the left rear leg roller do not move in the front and back directions, the right front leg and the left rear leg are bent forward synchronously until the height of the robot's four legs reaches the same level (such as state 5), so that the body recovers to the horizontal state.

Step 5: Since the left front, right rear and left rear foot form a stable support surface, the right front leg can be lifted off the ground and swing forward to a predetermined position (such as state 6).

Step 6: Drive the four legs to make the body of the robot translate forward as a whole, and ensure that the rollers on the four legs do not move in the front and rear directions (such as state 7).

Step 7: Bend the right front leg further forward and ensure that the right front leg roller does not move in the front-back direction, so that the center of gravity of the robot is shifted to the right front side. At the same time, because the height of the right front leg is lower than other legs, the robot body must tilt to the right front side , which makes the left rear portion of the robot body upwards and lifts the left rear leg off the ground (as state 8).

Step 8: After the left rear leg is lifted off the ground, drive the left rear leg to swing forward to the predetermined position (such as state 9). At this time, the center of gravity of the robot will only move within the support surface formed by the left front, right front and right rear feet. in static equilibrium.

Step 9: Under the condition of ensuring that the right front leg roller does not move in the front and back direction, the right front leg is gradually stretched upward until the height of the four legs of the robot reaches the same height, so that the body returns to the horizontal state (such as state 10).

Step 10: Stretch the four legs synchronously, and the robot returns to the initial upright state, so that the robot has successfully taken a step forward.

Repeat steps 1 to 10 above to realize continuous straight-line crawling.

Claims (5)

1. A multi-mode leg-wheel hybrid robot, comprising a body (1) and four legs (2) connected to the body, characterized in that a rotary drive motor (10) is installed at the end of each leg, forming a foot roller ( 5) Installed on the rotating shaft (11) of the rotary drive motor (10) through a one-way clutch (12). 2. The multi-mode leg-wheel hybrid robot according to claim 1, characterized in that the one-way clutch (12) is a one-way rolling bearing or a one-way rotating ratchet. 3. The multi-mode leg-wheel hybrid robot according to claim 1, characterized in that the four legs (2) are symmetrically distributed around the body (1) and each leg (2) has the same structure. 4. The multi-mode leg-wheel hybrid robot according to claim 1, characterized in that said robot legs (2) include thighs (3), calves (4) and rollers (5) forming feet, said thighs (3) The upper part of the upper leg (4) is rotationally connected with the trunk (1) to form a hip joint (6) that rotates around a horizontal axis, and the upper part of the lower leg (4) is rotationally connected with the lower part of the thigh (3) to form a knee joint that rotates around a horizontal axis (7), the lower part of the shank (4) is provided with an ankle joint (8) that rotates around the shank (4), and the roller (5) is connected to the end of the shank (4) to form a rolling wheel that rotates around a horizontal axis joint (9). 5. The multi-mode leg-wheel hybrid robot according to claim 1, characterized in that the rotating drive motor (10) is a motor with a self-locking function.