Multi-legged robot

Abstract

The invention discloses a multi-legged robot which comprises a rack and four movement feet arranged on the rack, and each movement foot comprises a parallel movement mechanism and an extended supporting leg connected with the parallel movement mechanism. The parallel movement mechanism comprises a movable platform, a static platform and three branch chains mounted between the static platform and the movable platform, and the static platform is connected with the rack; the extended supporting legs are connected with the movable platform, arranged on the side, away from the static platform, of the movable platform and extend towards the side, away from the static platform, of the movable platform. According to the multi-legged robot, the extended supporting legs are arranged in the moving feet, the extended supporting legs are arranged on the side, away from the static platform, of the moving platform, and the extended supporting legs extend towards the side, away from the static platform, of the moving platform, so that the lengths of the moving feet on the multi-legged robot are increased; therefore, the stride of the multi-legged robot is increased in the moving process of the robot.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, in particular to a multi-legged robot. Background Art

[0002] As a bionic leg-foot robot, the design concept of multi-legged robots is derived from the imitation of the walking style of quadrupeds in nature (such as dogs, cats, horses, etc.). This type of robot has a highly complex mechanical structure and precise control algorithm, combined with a variety of sensors, actuators and control systems, and has shown strong environmental adaptability. It can walk stably and perform tasks in a variety of complex terrains.

[0003] Although existing multi-legged robots show strong terrain adaptability and stability when performing tasks, they generally face the problem of small stride length, which to some extent limits their ability to cross obstacles. Summary of the invention

[0004] In order to solve the problem of small stride of existing multi-legged robots, the present invention provides a multi-legged robot.

[0005] To achieve the above object, the present invention adopts the following technical solution: The invention provides a multi-legged robot, which comprises a frame and four moving feet arranged on the frame, wherein the moving feet comprise a parallel kinematic mechanism and an extended supporting leg connected with the parallel kinematic mechanism.

[0006] The parallel motion mechanism includes a moving platform, a static platform and three branches installed between the static platform and the moving platform, the static platform is connected to the frame; the extended support leg is connected to the moving platform, the extended support leg is arranged on the side of the moving platform away from the static platform, and the extended support leg extends toward the side of the moving platform away from the static platform.

[0007] The beneficial effects are: The multi-legged robot of the present invention increases the length of each moving foot on the multi-legged robot by arranging an extended support leg in the moving foot, and arranging the extended support leg on the side of the moving platform away from the static platform, and the extended support leg extends toward the side of the moving platform away from the static platform, thereby increasing the stride of the multi-legged robot during the movement of the robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic structural diagram of a multi-legged robot according to Embodiment 1 of the present invention; Figure 2 is a schematic structural diagram of a first parallel kinematic machine according to embodiment 1 of the present invention; Figure 3 is a schematic structural diagram of a first extended support leg of Embodiment 1 of the present invention; Figure 4 is a schematic structural diagram of the first extended supporting leg from another perspective of Embodiment 1 of the present invention; Figure 5 is a schematic diagram of the structure of each drive control device on the multi-legged robot in Example 1 of the present invention; Figure 6 is a schematic structural diagram of the multi-legged robot from another perspective of Embodiment 1 of the present invention; Figure 7 yes Figure 6 A schematic diagram of the structure after hiding each movement foot; Figure 8 yes Figure 7 A structural diagram of the middle rack from another perspective; Fig. 9 yes Figure 6 A schematic diagram of the structure of the first vertical line and the first connecting line; Fig.10 is a schematic structural diagram of a multi-legged robot during movement according to an embodiment of the present invention; Fig.11 yes Fig.10 Schematic diagram of the structure after the ground contact points in the figure are projected onto the horizontal plane.

[0009] Figure numerals: 1, frame; 11, first angle; 12, second angle; 13, third angle; 14, fourth angle; 15, first mounting platform; 151, first mounting surface; 152, first vertical line; 16, second mounting platform; 17, third mounting platform; 18, fourth mounting platform; 19, fixed surface; 191, center point; 192, first connecting line; 2, first moving foot; 21, first parallel motion mechanism; 211, first static platform; 212, first moving platform; 213, first branch chain; 214, first driving motor; 215, rotating base; 22, first extended support leg; 221, first flange; 222 , first extension portion; 2221, first weight-reducing groove; 2222, second weight-reducing groove; 2223, weight-reducing hole; 223, first foot end; 2231, arc-shaped groove; 3, second movement foot; 4, third movement foot; 5, fourth movement foot; 6, first drive control device; 7, second drive control device; 8, third drive control device; 9, fourth drive control device; 101, center of gravity of the frame; 102, first ground contact point; 103, second ground contact point; 104, third ground contact point; 105, fourth ground contact point; X direction is the first direction; Y direction is the second direction; Z direction is the vertical direction. DETAILED DESCRIPTION

[0010] The present invention will be further described below in conjunction with the accompanying drawings: Example

[0011] As a bionic leg-and-foot robot, the design concept of multi-legged robots is derived from the imitation of the walking style of quadrupeds in nature (such as dogs, cats, horses, etc.). This type of robot has a highly complex mechanical structure and precise control algorithm, combined with a variety of sensors, actuators and control systems, and has shown strong environmental adaptability. It can walk stably and perform tasks in a variety of complex terrains.

[0012] Although existing multi-legged robots show strong terrain adaptability and stability when performing tasks, they generally face the problem of small stride length, which to some extent limits their ability to cross obstacles.

[0013] In order to solve the problem of small stride of existing multi-legged robots, this embodiment provides a multi-legged robot. Figure 1 As shown, the multi-legged robot includes a frame 1, a first moving foot 2, a second moving foot 3, a third moving foot 4 and a fourth moving foot 5. The frame 1 is in the shape of a rectangular parallelepiped, and the four corners of the frame 1 are respectively a first corner 11, a second corner 12, a third corner 13 and a fourth corner 14. The first moving foot 2, the second moving foot 3, the third moving foot 4 and the fourth moving foot 5 are respectively arranged at the four corners of the frame 1. Specifically, the first moving foot 2 is arranged at the first corner 11 of the frame 1, the second moving foot 3 is arranged at the second corner 12 of the frame 1, the third moving foot 4 is arranged at the third corner 13 of the frame 1, and the fourth moving foot 5 is arranged at the fourth corner 14 of the frame 1.

[0014] The first movement foot 2 comprises a first parallel movement mechanism 21 and a first extended support leg 22 connected to the first parallel movement mechanism 21. Figure 2 As shown, the first parallel kinematic mechanism 21 is a 3-UPS type parallel mechanism, and the first parallel kinematic mechanism 21 includes a first static platform 211, a first dynamic platform 212, three first drive motors 214, and three first branch chains 213 installed between the static platform and the dynamic platform. Figures 1 to 3 As shown, the first static platform 211 is connected to the frame 1, the first dynamic platform 212 is connected to the first extended support leg 22, the first extended support leg 22 is arranged on the side of the first dynamic platform 212 away from the first static platform 211, and the first extended support leg 22 extends toward the side of the first dynamic platform 212 away from the first static platform 211, that is, the first extended support leg 22 extends toward the side of the parallel motion mechanism away from the frame 1.

[0015] like Figure 2 As shown, three first branches 213 connect the first static platform 211 and the first moving platform 212, wherein each first branch chain 213 is a telescopic structure, and each first branch chain 213 is connected to the first moving platform 212 via a ball joint. Three rotating bases 215 are rotatably mounted on the first static platform 211, and the rotating axis of the rotating base 215 on the first static platform 211 is as shown in FIG. Figure 2 As shown in the middle A axis. A U-shaped hinge is installed on the rotating base 215, and the first branch chain 213 is rotatably installed on the U-shaped hinge. Three first drive motors 214 are installed on the first static platform 211, and each first drive motor 214 corresponds to a rotating base 215. The output shaft of the first drive motor 214 is arranged parallel to the rotating axis of the rotating base 215, and the output shaft of the first drive motor 214 drives the rotating base 215 to rotate through a belt drive, thereby driving the first branch chain 213 to rotate. In other embodiments, the first parallel motion mechanism 21 can also be an existing parallel motion mechanism, such as the parallel robotic arm structure in CN221844976U.

[0016] In this embodiment, the structures of the second movement foot 3, the third movement foot 4, and the fourth movement foot 5 are similar to the structure of the first movement foot 2, so they are not described again.

[0017] The multi-legged robot of the present invention increases the length of each moving foot on the multi-legged robot by arranging an extended support leg in the moving foot, and arranging the extended support leg on the side of the moving platform away from the static platform, and the extended support leg extends toward the side of the moving platform away from the static platform, thereby increasing the stride of the multi-legged robot during the movement of the robot.

[0018] like Figure 3 and Figure 4 As shown, the first extended support leg 22 includes a first flange portion 221, a first extension portion 222 and a first foot end portion 223. The first movable platform 212, the first flange portion 221, the first extension portion 222 and the first foot end portion 223 are connected in sequence, and the first foot end portion 223 is in contact with the ground. The first flange portion 221, the first extension portion 222 and the first foot end portion 223 are an integrated structure. Figure 1 As shown, the length direction of the multi-legged robot is defined as the first direction ( Figure 1 In the X-axis direction, the plane where the first direction and the vertical direction are located is the first plane. The cross section of the first extension part 222 in the first plane is triangular in shape, and the first extension part 222 is provided with a first weight-reducing groove 2221 and a second weight-reducing groove 2222 on the opposite sides of the first plane, respectively. The first weight-reducing groove 2221 and the second weight-reducing groove 2222 have the same shape. In addition, a weight-reducing hole 2223 is provided on the first extension part 222, and the weight-reducing hole 2223 is connected with the first weight-reducing groove 2221 and the second weight-reducing groove 2222, respectively. The first foot end part 223 is spherical, and the first foot end part 223 is provided with a plurality of arc-shaped grooves 2231; the plurality of arc-shaped grooves 2231 are evenly distributed on the first foot end part 223 in an annular manner on the first plane.

[0019] like Figure 5As shown, the multi-legged robot further includes a first drive control device 6, a second drive control device 7, a third drive control device 8 and a fourth drive control device 9, which are respectively arranged at the four corners of the frame 1. Specifically, the first drive control device 6 is arranged at the first corner 11 of the frame 1, the second drive control device 7 is arranged at the second corner 12 of the frame 1, the third drive control device 8 is arranged at the third corner 13 of the frame 1, and the fourth drive control device 9 is arranged at the fourth corner 14 of the frame 1. Among them, the first drive control device 6 controls the movement of the first moving foot 2, the second drive control device 7 controls the movement of the second moving foot 3, the third drive control device 8 controls the movement of the third moving foot 4, and the fourth drive control device 9 controls the movement of the fourth moving foot 5. In this embodiment, the drive control device is a motor drive board, and the drive control device controlling the movement of the moving foot means that the drive control device controls the movement of the output shaft of the drive motor in the moving foot, thereby controlling the movement of the moving foot.

[0020] In this embodiment, four driving control devices are distributed at the four corners of the frame 1, so that the multi-legged robot can move more smoothly.

[0021] like Figure 5 As shown, each driving control device is arranged above the frame 1, and each moving foot is arranged below the frame 1, so that each driving control device and a moving foot controlled by it are respectively arranged on the upper and lower opposite sides of the frame 1.

[0022] like Figure 6 and Figure 7 As shown, the first mounting platform 15, the second mounting platform 16, the third mounting platform 17 and the fourth mounting platform 18 are respectively provided at the four corners of the fixed surface 19 on the frame 1, the first movement foot 2 is correspondingly installed on the first mounting platform 15, the second movement foot 3 is correspondingly installed on the second mounting platform 16, the third movement foot 4 is correspondingly installed on the third mounting platform 17, and the fourth movement foot 5 is correspondingly installed on the fourth mounting platform 18. The first mounting platform 15 is provided with a first mounting surface 151, and the first movement foot 2 is installed on the first mounting surface 151. Figure 7 As shown, there is an inclination angle θ between the first mounting surface 151 and the fixing surface 19 . In this embodiment, the inclination angle θ may be 15 degrees to 25 degrees.

[0023] like Figure 8 As shown, the line connecting the center point 191 on the fixed surface 19 to the first corner 11 is the first connecting line 192. Fig. 9As shown, the straight line perpendicular to the first mounting surface 151 is the first vertical line 152, the first connecting line 192 is coplanar with the first vertical surface, and there is a first clamping angle α between the first connecting line 192 and the first vertical line 152. In this embodiment, the first clamping angle α can be 65 degrees to 75 degrees.

[0024] The structures of the second mounting platform 16 , the third mounting platform 17 , and the fourth mounting platform 18 are the same as that of the first mounting platform 15 , and thus will not be described in detail.

[0025] On the other hand, when the existing multi-legged robot performs tasks, there will be problems such as unstable center of gravity causing the robot to roll over. In order to solve the problem of unstable center of gravity causing the robot to roll over when performing tasks, this embodiment also proposes a control method for a multi-legged robot, and the multi-legged robot is the multi-legged robot in the above embodiment. Among them, a force sensor is set between the moving platform and the extended support leg in each moving foot of this embodiment, so when the moving foot contacts the ground, the force sensor detects the signal of the moving foot contacting the ground, and the system receives the signal transmitted by the force sensor, which means that the moving foot is in contact with the ground.

[0026] Specifically, the control method of the multi-legged robot includes the following steps: S1, obtaining the position of the contact point between each moving foot and the ground according to the posture of each moving foot and the signal of the force sensor in each moving foot; S2, confirming the sports foot that can stably move according to the position of the contact point between each sports foot and the ground and the position of the center of gravity point 101 of the frame; S3, confirming the moving foot to be moved according to the posture of each moving foot that can stably move; S4, driving the moving foot to be moved.

[0027] Specifically, in the above step S1, when the system receives the signal from the force sensor in each moving foot, it means that each moving foot is in contact with the ground at this time, and the posture parameters of each joint in the parallel motion mechanism in each moving foot can be obtained by the system at this time, so the system can calculate the position of the contact point between the moving foot and the ground according to the posture parameters of each joint, that is, Fig.10 The positions of the first ground contact point 102, the second ground contact point 103, the third ground contact point 104, and the fourth ground contact point 105. In addition, if the system does not receive a signal from a force sensor in a certain moving foot, it means that the moving foot is not in contact with the ground, so at this time, it is necessary to drive the moving foot to move so that the moving foot is in contact with the ground (driving the moving foot to move can be achieved by driving the branch chain in the parallel motion mechanism to extend so that the moving foot is in contact with the ground. If the branch chain in the parallel motion mechanism cannot extend so that the moving foot is in contact with the ground, the system will give an alarm).

[0028] The above step S2 comprises: S21, projecting the position of the center of gravity point 101 of the rack onto a horizontal plane; Fig.11 As shown, the position of the center of gravity point 101 of the rack is projected on the horizontal plane to obtain the center of gravity projection point O; S22, projecting the contact point between each moving foot and the ground onto a horizontal plane; Fig.11 As shown, each ground contact point 102 is projected on a horizontal plane to obtain a first projection point C, a second projection point D, a third projection point E, and a fourth projection point F.

[0029] S23, connect the projections of the first movement foot 2, the second movement foot 3, the third movement foot 4 and the ground contact point on the horizontal plane to form a first triangle, and determine whether the projection of the frame center of gravity 101 on the horizontal plane is located within the first triangle. If so, confirm that the fourth movement foot 5 is a movement foot that can stably move. Fig.11 As shown, the center of gravity projection point O is located within △CDE, so the fourth movement foot 5 is confirmed to be a movement foot that can stably move. Since the center of gravity projection point O is located within △CDE, the first movement foot 2, the second movement foot 3, and the third movement foot 4 can be used as support to ensure the stability of the frame 1 during the movement of the fourth movement foot 5, so the fourth movement foot 5 is confirmed to be a movement foot that can stably move.

[0030] S24, connect the projections of the first movement foot 2, the second movement foot 3, the fourth movement foot 5 and the ground contact point on the horizontal plane to form a second triangle, and determine whether the projection of the frame center of gravity 101 on the horizontal plane is located within the second triangle. If so, confirm that the third movement foot 4 is a movement foot that can stably move. Fig.11 As shown, the center of gravity projection point O is outside △CDF, so it is confirmed that the third moving foot 4 is not a moving foot that can stably move. Since the center of gravity projection point O is outside △CDF, the first moving foot 2, the second moving foot 3, and the fourth moving foot 5 cannot ensure the stability of the frame 1 during the movement of the third moving foot 4.

[0031] S25, connect the projections of the first movement foot 2, the third movement foot 4, the fourth movement foot 5 and the ground contact point on the horizontal plane to form a third triangle, and determine whether the projection of the frame center of gravity 101 on the horizontal plane is within the third triangle. If so, confirm that the second movement foot 3 is a movement foot that can stably move. Fig.11 As shown, the center of gravity projection point O is located within △CEF, so the second moving foot 3 is confirmed to be a moving foot that can stably move. Since the center of gravity projection point O is located within △CEF, the first moving foot 2, the third moving foot 4, and the fourth moving foot 5 can be used as support to ensure the stability of the frame 1 during the movement of the second moving foot 3, so the second moving foot 3 is confirmed to be a moving foot that can stably move.

[0032] S26, connect the projections of the fourth movement foot 5, the second movement foot 3, the third movement foot 4 and the ground contact point on the horizontal plane to form a fourth triangle, and determine whether the projection of the frame center of gravity 101 on the horizontal plane is within the fourth triangle. If so, confirm that the first movement foot 2 is a movement foot that can stably move. Fig.11 As shown, the center of gravity projection point O is outside △DEF, so it is confirmed that the first moving foot 2 is not a moving foot that can stably move. Since the center of gravity projection point O is outside △DEF, the stability of the frame 1 cannot be guaranteed during the movement of the first moving foot 2 by using the fourth moving foot 5, the second moving foot 3, and the third moving foot 4 as support.

[0033] Through the above steps S21 to S26, it is confirmed that if the multi-legged robot drives the second moving foot 3 or the fourth moving foot 5, the frame 1 can be guaranteed to be stable, so it is confirmed that the second moving foot 3 or the fourth moving foot 5 is a moving foot that can move stably.

[0034] The above steps S21 to S26 confirm that there are two moving feet that can move stably, so step S3 needs to confirm which moving foot that can move stably is driven by the multi-legged robot to move. Step S3 determines the posture force condition of each moving foot through the posture of each moving foot that can move stably, and confirms the moving foot with the weakest posture force condition as the moving foot to be moved, that is, the moving foot with the weakest posture force condition is confirmed as the moving foot that the multi-legged robot needs to drive to move.

[0035] Specifically, there are many ways to determine the posture force conditions of each sports foot. This embodiment uses an example, for example, to determine which of the second sports foot 3 and the fourth sports foot 5 has a larger angle between the moving platform and the horizontal plane, and then determine which sports foot is the sports foot to be moved; for example, according to the posture system of the second sports foot 3, the angle between the moving platform and the horizontal plane in the second sports foot 3 is calculated to be 10 degrees, and according to the posture system of the fourth sports foot 5, the angle between the moving platform and the horizontal plane in the fourth sports foot 5 is calculated to be 30 degrees, then the fourth sports foot 5 is determined to be the sports foot to be moved. Since the posture force condition of the second sports foot 3 is better than the posture force condition of the fourth sports foot 5, it is better to select the second sports foot 3 as a support to drive the fourth sports foot 5 to move, than to select the fourth sports foot 5 as a support to drive the second sports foot 3 to move.

[0036] The above step S4 comprises: S41, driving the moving foot to be moved to contract to a contracted state; in this embodiment, the contraction of the moving foot to the contracted state is achieved by driving the branch chain in each moving foot to shorten.

[0037] S42, driving the moving foot to be moved to swing to a preset angle; in this embodiment, the branch chain in each moving foot is driven to rotate, thereby driving the movement to swing, for example, driving the moving foot to swing 30°.

[0038] S43, driving the moving foot to be moved to extend; in this embodiment, the extension of the moving foot is achieved by driving the branch chain in each moving foot to extend.

[0039] S44. When the force sensor on the moving foot to be moved detects force, the moving foot to be moved stops extending.

[0040] Through the above steps S1 to S4, the system can ensure that the multi-legged robot drives the moving legs to move forward in the most stable state, thereby avoiding the situation where the multi-legged robot rolls over due to unstable center of gravity when performing tasks.

[0041] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A multi-legged robot, comprising a frame and four moving legs arranged on the frame, characterized in that: The sports foot includes a parallel motion mechanism and an extended support leg connected to the parallel motion mechanism; The parallel motion mechanism includes a moving platform, a static platform and three branches installed between the static platform and the moving platform, the static platform is connected to the frame; the extended support leg is connected to the moving platform, the extended support leg is arranged on the side of the moving platform away from the static platform, and the extended support leg extends toward the side of the moving platform away from the static platform.

2. A multi-legged robot according to claim 1, characterized in that: The extended support leg includes a flange portion, an extension portion and a foot end portion. The movable platform, the flange portion, the extension portion and the foot end portion are connected in sequence, and the foot end portion is in contact with the ground.

3. A multi-legged robot according to claim 2, characterized in that: The length direction of the multi-legged robot is a first direction, the plane where the first direction and the vertical direction are located is a first plane, the cross-section of the extension part in the first plane is triangular, and the extension part is respectively provided with a first weight-reducing groove and a second weight-reducing groove on two opposite side surfaces along the first plane.

4. A multi-legged robot according to claim 3, characterized in that: The first weight-reducing groove and the second weight-reducing groove have the same shape.

5. A multi-legged robot according to claim 4, characterized in that: The extension portion is also provided with a weight-reducing hole, and the weight-reducing hole is communicated with the first weight-reducing groove and the second weight-reducing groove respectively.

6. A multi-legged robot according to claim 5, characterized in that: The foot end portion is spherical and is provided with a plurality of arc-shaped grooves; on the first plane, the plurality of arc-shaped grooves are evenly distributed on the foot end portion.

7. A multi-legged robot according to any one of claims 1 to 6, characterized in that: The multi-legged robot also includes four drive control devices respectively arranged at the four corners of the frame, and the four moving feet are respectively arranged at the four corners of the frame. Each of the drive control devices controls the movement of one of the moving feet respectively, and each of the drive control devices and one of the moving feet it controls are located in the same corner of the frame.

8. A multi-legged robot according to claim 7, characterized in that: Each of the driving control devices and one of the moving feet it controls are respectively arranged on opposite sides of the frame.

9. A multi-legged robot according to claim 8, characterized in that: A mounting platform is provided at the four corners of the fixed surface on the frame relative to each of the sports feet, and each of the mounting platforms is provided with a mounting surface, and an inclination angle is formed between the mounting surface on each of the mounting platforms and the fixed surface; each of the sports feet is respectively mounted on the mounting surface of the mounting platform corresponding to the sports foot.

10. A multi-legged robot according to claim 9, characterized in that: The sports foot comprises a first sports foot, a first mounting platform is provided at a first corner of the fixing surface relative to the first sports foot, a first mounting surface is provided on the first mounting platform, an inclination angle is formed between the first mounting surface and the fixing surface, and the first sports foot is mounted on the first mounting surface; A line from the center point of the fixing surface to the first angle is a first connecting line, a straight line perpendicular to the first mounting surface is a first vertical line, the first connecting line is coplanar with the first vertical surface, and a first clamping angle is formed between the first connecting line and the first vertical line.

Images