A multi-loop spherical robot based on bricard mechanism derivation

Abstract

The application relates to mobile robot technology and particularly relates to a multi-loop spherical robot derived from a Bricard mechanism, which is composed of a first spherical shell, a second spherical shell, a third spherical shell, a fourth spherical shell, a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod, a fifth connecting rod, a sixth connecting rod, a seventh connecting rod, an eighth connecting rod, a first connecting base, a second connecting base, a third connecting base, a fourth connecting base, a fifth connecting base and a sixth connecting base, and a driving motor, wherein the multi-loop derived from the Bricard mechanism is combined with the spherical shell, a new configuration of a single-degree-of-freedom driving spherical robot is obtained, and the spherical robot has the motion ability of a tumbling gait, a peristalsis gait and a self-rotation gait.

Description

Technical Field

[0001] This invention relates to mobile robot technology, specifically to a multi-loop spherical robot based on the Bricard mechanism, which can drive the spherical shell to autonomously unfold and fold to achieve movement functions. Background Technology

[0002] Spherical robots utilize a spherical shell to achieve rapid rolling on the ground while ensuring stability during movement. Furthermore, the point contact between the spherical shell and the ground effectively reduces motion resistance. The Bricard mechanism consists of six rigid links connected by revolute joints, forming a spatial closed-loop chain. Its core characteristic is over-constraint yet movable, satisfying the constraints of single-degree-of-freedom motion and enabling flexible spatial movement. Utilizing this characteristic, it can be used as a folding and unfolding drive mechanism for spherical robots. The external links are constructed with a spherical shape, and multiple loops derived from the Bricard mechanism are combined with the spherical shell to obtain a novel configuration of a single-degree-of-freedom driven spherical robot with rolling, creeping, and spinning gait capabilities.

[0003] Chinese patent CN105690375B discloses "A single-degree-of-freedom four-bar linkage mobile robot and its control method". This invention proposes a single-degree-of-freedom four-bar linkage mobile robot and its control method, which realizes the single-degree-of-freedom robot's straight-line movement and deterministic turning motion in a plane. Summary of the Invention

[0004] A multi-loop spherical robot based on the Bricard mechanism consists of a first spherical shell, a second spherical shell, a third spherical shell, a fourth spherical shell, a first connecting seat, a second connecting seat, a third connecting seat, a fourth connecting seat, a fifth connecting seat, a sixth connecting seat, a first link, a second link, a third link, a fourth link, a fifth link, a sixth link, a seventh link, an eighth link, and a drive motor.

[0005] The connection method of the parts that make up the mechanism:

[0006] The single-hole and double-hole surfaces at the beginning of the first, second, third, fourth, sixth, and seventh links are connected by revolute joints. Specifically, the single-hole surface at the beginning of the first link is connected to the double-hole surface at the beginning of the second link, the single-hole surface at the beginning of the second link is connected to the double-hole surface at the beginning of the seventh link, the single-hole surface at the beginning of the seventh link is connected to the double-hole surface at the beginning of the sixth link, the single-hole surface at the beginning of the sixth link is connected to the double-hole surface at the beginning of the third link, the single-hole surface at the beginning of the third link is connected to the double-hole surface at the beginning of the fourth link, and the single-hole surface at the beginning of the fourth link is connected to the double-hole surface at the beginning of the first link, thus forming a Bricard closed-loop structure.

[0007] The tail end of the first link is connected to the first connecting seat via a revolute joint; the tail end of the second link is connected to the second connecting seat via a revolute joint; the tail end of the third link is connected to the fourth connecting seat via a revolute joint; the tail end of the fourth link is connected to the fifth link via a revolute joint; one end of the fifth link is connected to the third connecting seat via a revolute joint; the tail end of the sixth link is connected to the sixth connecting seat via a revolute joint; the tail end of the seventh link is connected to one end of the eighth link via a revolute joint; and one end of the eighth link is connected to the fifth connecting seat via a revolute joint.

[0008] The first spherical shell is fixedly connected to the first connecting seat through bolt holes, the second spherical shell is fixedly connected to the second connecting seat through bolt holes, the third spherical shell is fixedly connected to the third and fourth connecting seats through bolt holes, and the fourth spherical shell is fixedly connected to the fifth and sixth connecting seats through bolt holes, forming a Bennett loop irregular structure.

[0009] The two sides of the drive motor body are fixedly connected to the first spherical shell through bolt holes, and the two sides of the drive motor shaft are fixedly connected to the second spherical shell through bolt holes.

[0010] The drive motor drives a first and a second spherical shell connected by a revolute joint. The first spherical shell drives a fixedly connected first connecting seat, and the second spherical shell drives a fixedly connected second connecting seat. The first connecting seat drives a first connecting rod via a revolute joint, the second connecting seat drives a second connecting rod via a revolute joint, the first connecting rod drives a fourth connecting rod via a revolute joint, and the second connecting rod drives a seventh connecting rod via a revolute joint. The fourth connecting rod drives a third and a fifth connecting rod via a revolute joint, and the seventh connecting rod drives a sixth and a eighth connecting rod via a revolute joint. The third connecting rod drives a fourth connecting seat via a revolute joint, the fifth connecting rod drives a third connecting seat via a revolute joint, the sixth connecting rod drives a sixth connecting seat via a revolute joint, and the eighth connecting rod drives a fifth connecting seat via a revolute joint. The third and fourth connecting seats drive a fixedly connected third spherical shell, and the fifth and sixth connecting seats drive a fixedly connected fourth spherical shell.

[0011] The structure of the components that make up the mechanism:

[0012] The first spherical shell is a quarter-sphere in shape. Its surface has two bolt holes for fixed connection with the first connecting seat, three through holes for fixed connection with the front of the drive motor body, and four through holes for fixed connection with the back of the drive motor body.

[0013] The second spherical shell is a quarter-sphere in shape. Its surface has two bolt holes for fixed connection to the second connecting seat, and five through holes for fixed connection to one side of the drive motor shaft, and another five through holes for fixed connection to the other side of the drive motor shaft.

[0014] The third spherical shell is shaped like a quarter sphere. Its surface has two bolt holes for fixing it to the third connecting seat, and two additional bolt holes for fixing it to the fourth connecting seat.

[0015] The fourth spherical shell is shaped like a quarter sphere. Its surface has two bolt holes for fixing it to the fifth connecting seat, and two additional bolt holes for fixing it to the sixth connecting seat.

[0016] The first connecting rod is T-shaped, and its tail end is connected to the first connecting seat through a rotating joint. Its head end is divided into a single-hole surface and a double-hole surface.

[0017] The second connecting rod is T-shaped, with its tail end connected to the second connecting seat via a rotating joint, and its head end divided into a single-hole surface and a double-hole surface.

[0018] The third link is T-shaped, with its tail end connected to the fourth connecting seat via a revolute joint, and its head end divided into a single-hole surface and a double-hole surface. The seventh link has the same structure and dimensions as the third link.

[0019] The fourth link is T-shaped, with its tail end connected to the fifth link via a revolute joint, and its head end has a single-hole surface and a double-hole surface. The sixth link has the same structure and dimensions as the fourth link.

[0020] The fifth link is a long straight rod, one end of which is connected to the third connecting seat via a revolute joint, and the other end is connected to the tail end of the fourth link via a revolute joint. The eighth link has the same structure and external dimensions as the fifth link.

[0021] The lengths of the first, second, third, fourth, fifth, sixth, seventh, and eighth links shall not exceed the diameter of the spherical shell.

[0022] The first, second, third, fourth, fifth, and sixth connecting seats are all identical in shape, with a large through hole at the top for connecting to each connecting rod via a rotating joint, and two small through holes at the bottom for fixing to each spherical shell.

[0023] The beneficial effects of this invention are as follows: The multi-loop spherical robot based on the Bricard mechanism described in this invention fully combines the unfolding characteristics of the spatially constrained mechanism with the flexible movement performance of the spherical robot. By changing the unfolding position and the ground contact area, it possesses three gait modes: passive rolling, peristalsis, and spin. The passive rolling gait utilizes the spherical shell for rolling motion, offering good flexibility and enabling rapid movement on flat surfaces. The peristaltic gait provides better ground stability and allows for precise linear movement with small strides. The spin gait utilizes rotation around a central axis to change the angle of movement direction. These three gait modes can be switched according to different work requirements, enabling traversal of the work area. Attached Figure Description

[0024] Figure 1 Assembly diagram of a multi-loop spherical robot derived from the Bricard mechanism

[0025] Figure 2 Structural diagrams of the first, second, third, and fourth spherical shells.

[0026] Figure 3 Structural diagrams of the first, second, third, fourth, and fifth links.

[0027] Figure 4 First connecting seat structure diagram

[0028] Figure 5 Schematic diagram of the unfolding and deformation of a multi-loop spherical robot derived from the Bricard mechanism.

[0029] Figure 6 Schematic diagram of passive rolling gait of a multi-loop spherical robot derived from the Bricard mechanism

[0030] Figure 7 Schematic diagram of the peristaltic gait of a multi-loop spherical robot derived from the Bricard mechanism.

[0031] Figure 8 Schematic diagram of the spin gait of a multi-loop spherical robot derived from the Bricard mechanism. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings.

[0033] like Figure 1As shown, a multi-loop spherical robot based on the Bricard mechanism consists of a first spherical shell (1), a second spherical shell (2), a third spherical shell (3), a fourth spherical shell (4); a first link (5), a second link (6), a third link (7), a fourth link (8), a fifth link (9), a sixth link (10), a seventh link (11), an eighth link (12); a first connecting seat (13), a second connecting seat (14), a third connecting seat (15), a fourth connecting seat (16), a fifth connecting seat (17), a sixth connecting seat (18); and a drive motor (19).

[0034] The connection method of the parts that make up the mechanism:

[0035] The single-hole surface and double-hole surface at the beginning of the first link (5), second link (6), third link (7), fourth link (8), sixth link (10), and seventh link (11) are connected by a revolute joint. Specifically, the single-hole surface (5-1) at the beginning of the first link (5) is connected to the double-hole surfaces (6-1) and (6-2) at the beginning of the second link (6) by a revolute joint, and the single-hole surface (6-3) at the beginning of the second link (6) is connected to the double-hole surface (11-2) at the beginning of the seventh link (11). (11-3) The single-hole surface (11-1) at the beginning of the seventh link (11) is connected to the double-hole surfaces (10-1) and (10-2) at the beginning of the sixth link (10) via a rotating joint. The single-hole surface (10-3) at the beginning of the sixth link (10) is connected to the double-hole surfaces (7-2) and (7-3) at the beginning of the third link (7) via a rotating joint. The single-hole surface (7-1) at the beginning of the third link (7) is connected to the double-hole surfaces (8-1) and (8-2) at the beginning of the fourth link (8) via a rotating joint. The single-hole surface (8-3) at the beginning of the fourth link (8) is connected to the double-hole surfaces (5-2) and (5-3) at the beginning of the first link (5) via a rotating joint, thus forming a Bricard closed-loop structure.

[0036] The tail ends (5-4) and (5-5) of the first connecting rod (5) are connected to the first connecting seat (13) via a revolute joint; the tail ends (6-4) and (6-5) of the second connecting rod (6) are connected to the second connecting seat (14) via a revolute joint; the tail end (7-4) of the third connecting rod (7) is connected to the fourth connecting seat (16) via a revolute joint; the tail end (8-4) of the fourth connecting rod (8) is connected to one end (9-3) of the fifth connecting rod (9) via a revolute joint; the fifth connecting rod... One end (9-1) and (9-2) of the rod (9) are connected to the third connecting seat (15) via a revolute joint. The tail end (10-4) of the sixth connecting rod (10) is connected to the sixth connecting seat (18) via a revolute joint. The tail end (11-4) of the seventh connecting rod (11) is connected to one end (12-3) of the eighth connecting rod (12) via a revolute joint. One end (12-1) and (12-2) of the eighth connecting rod (12) are connected to the fifth connecting seat (17) via a revolute joint.

[0037] The first spherical shell (1) is fixedly connected to the first connecting seat (13) through bolt holes (1-8) and (1-9), the second spherical shell (2) is fixedly connected to the second connecting seat (14) through bolt holes (2-1) and (2-2), the third spherical shell (3) is fixedly connected to the third connecting seat (15) and the fourth connecting seat (16) through bolt holes (3-3), (3-4), (3-1), and (3-2), and the fourth spherical shell (4) is fixedly connected to the fifth connecting seat (17) and the sixth connecting seat (18) through bolt holes (4-1), (4-2), (4-3), and (4-4).

[0038] The two sides of the drive motor (19) are fixedly connected to the first spherical shell (1) through bolt holes, and the two sides of the shaft of the drive motor (19) are fixedly connected to the second spherical shell (2) through bolt holes.

[0039] The drive motor (19) drives the connected first spherical shell (1) and second spherical shell (2) to move via a rotary joint. The first spherical shell (1) drives the fixedly connected first connecting seat (13) to move, and the second spherical shell (2) drives the fixedly connected second connecting seat (14) to move. The first connecting seat (13) drives the first connecting rod (5) to move via a rotary joint, and the second connecting seat (14) drives the second connecting rod (6) to move via a rotary joint. The first connecting rod (5) drives the fourth connecting rod (8) to move via a rotary joint, and the second connecting rod (6) drives the seventh connecting rod (11) to move via a rotary joint. The fourth connecting rod (8) drives the third connecting rod (7) and the fifth connecting rod (9) to move via a rotary joint, and the seventh connecting rod (11) drives the sixth connecting rod (10) and the eighth connecting rod (12) to move via a rotary joint. The third link (7) drives the fourth connecting seat (16) to move through a revolute joint; the fifth link (9) drives the third connecting seat (15) to move through a revolute joint; the sixth link (10) drives the sixth connecting seat (18) to move through a revolute joint; and the eighth link (12) drives the fifth connecting seat (17) to move through a revolute joint. The third connecting seat (15) and the fourth connecting seat (16) drive the fixedly connected third spherical shell (3) to move; and the fifth connecting seat (17) and the sixth connecting seat (18) drive the fixedly connected fourth spherical shell (4) to move.

[0040] The structure of the components that make up the mechanism:

[0041] like Figure 2 As shown in (a), the first spherical shell (1) is a quarter sphere in shape. Its surface is provided with two bolt holes (1-8) and (1-9) for fixed connection with the first connecting seat (13), and three through holes (1-1), (1-2) and (1-3) for fixed connection with the front of the body of the drive motor (19), and four through holes (1-4), (1-5), (1-6) and (1-7) for fixed connection with the back of the body of the drive motor (19).

[0042] like Figure 2 As shown in (b), the second spherical shell (2) is a quarter sphere. Its surface is provided with two bolt holes (2-1) and (2-2) for fixed connection with the second connecting seat (14), and five through holes (2-3), (2-4), (2-5), (2-6), and (2-7) for fixed connection with one side of the shaft of the drive motor (19), and five more through holes (2-8), (2-9), (2-10), (2-11), and (2-12) for fixed connection with the other side of the shaft of the drive motor (19).

[0043] like Figure 2As shown in (c), the third spherical shell (3) is a quarter sphere. Its surface is provided with two bolt holes (3-3) and (3-4) for fixed connection with the third connecting seat (15), and two bolt holes (3-1) and (3-2) for fixed connection with the fourth connecting seat (16).

[0044] like Figure 2 As shown in (d), the fourth spherical shell (4) is a quarter sphere in shape. Its surface is provided with two bolt holes (4-1) and (4-2) for fixed connection with the fifth connecting seat (17), and two bolt holes (4-3) and (4-4) for fixed connection with the sixth connecting seat (18).

[0045] like Figure 3 As shown in (a), the first connecting rod (5) is T-shaped, and its tail end (5-4) and (5-5) are connected to the first connecting seat (5) through a rotating joint. Its head end is divided into a single hole surface (5-1) and a double hole surface (5-2) and (5-3).

[0046] like Figure 3 As shown in (b), the second connecting rod (6) is T-shaped, and its tail end (6-4) and (6-5) are connected to the second connecting seat (6) through a rotating joint. Its head end is divided into a single hole surface (6-3) and a double hole surface (6-1) and (6-2).

[0047] like Figure 3 As shown in (c), the third link (7) is T-shaped, with its tail end (7-4) connected to the fourth connecting seat (8) via a rotating joint, and its head end divided into a single-hole surface (7-1) and double-hole surfaces (7-2) and (7-3). The structure and external dimensions of the seventh link (11) are the same as those of the third link (7).

[0048] like Figure 3 As shown in (d), the fourth link (8) is T-shaped, and its tail end (8-4) is connected to the fifth link (9) through a rotating joint. Its head end is divided into a single-hole surface (8-3) and a double-hole surface (8-1) and (8-2). The structure and external dimensions of the sixth link (10) are the same as those of the fourth link (8).

[0049] like Figure 3 As shown in (e), the fifth link (9) is a long straight rod, one end (9-1) and (9-2) of which are connected to the third connecting seat (15) via a revolute joint, and the other end (9-3) of which is connected to the tail end (8-4) of the fourth link (8) via a revolute joint. The eighth link (12) has the same structure and external dimensions as the fifth link (9).

[0050] The lengths of the first link (5), second link (6), third link (7), fourth link (8), fifth link (9), sixth link (10), seventh link (11), and eighth link (12) shall not exceed the diameter of the spherical shell.

[0051] like Figure 4 As shown, the first connecting seat (13) has a large through hole (13-1) at the top for connecting with each connecting rod via a rotating joint, and two small through holes (13-2) and (13-3) at the bottom for fixing with each spherical shell. The second connecting seat (14), third connecting seat (15), fourth connecting seat (16), fifth connecting seat (17), and sixth connecting seat (18) have the same shape as the first connecting seat (13).

[0052] Specific usage instructions:

[0053] A multi-loop spherical robot derived from the Bricard mechanism can perform single-degree-of-freedom driven unfolding and deformation, such as... Figure 5 The image shows two states of a spherical robot. Figure 5 (a) is the fully folded state of the spherical robot. In this state, the four spherical shells of the mechanism are completely folded up, and the overall shape is spherical. The drive motor (19) rotates forward, causing the first spherical shell (1), the second spherical shell (2), the third spherical shell (3), and the fourth spherical shell (4) to separate. After being fully unfolded, the four spherical shells are separated from each other, which is the maximum unfolded state, as shown in the figure. Figure 5 As shown in (b). Similarly, reversing the drive motor (19) can cause the spherical robot to change from a fully unfolded state to a fully folded state.

[0054] A multi-loop spherical robot derived from the Bricard mechanism can perform passive tumbling, including both rolling in a straight line and rolling turning. For example... Figure 6 The image shows the spherical robot completing one cycle of passive tumbling. Figure 6 (a) is the fully folded state of the spherical robot. In this state, the four spherical shells of the mechanism are completely folded up, and the overall shape is spherical. The drive motor (19) rotates forward, causing the first spherical shell (1), the second spherical shell (2), the third spherical shell (3), and the fourth spherical shell (4) to separate. After being fully unfolded, the four spherical shells separate from each other and deform into an unfolded state, as shown in the figure. Figure 6 As shown in (b), when the projected position of the centroid exceeds the support area, it tilts forward, as... Figure 6 As shown in (c). During the tilting process, the drive motor (19) reverses to cause the spherical robot to change from an unfolded state to a fully folded state, forming an enclosing spherical surface, as shown in (c). Figure 6As shown in (d), the spherical robot achieves rolling straight movement by relying on the spherical contour and tilting kinetic energy. The principle of rolling steering is similar to that of rolling straight movement. When the spherical robot reaches the turning critical position during the straight rolling process, the opening and closing speed of the spherical shell is changed by adjusting the speed of the drive motor (19). The spherical shell contacts the ground during the opening and closing process to form a turning tendency, thereby achieving steering.

[0055] A multi-loop spherical robot based on the Bricard mechanism can perform peristaltic movements. For example... Figure 7 The image shows the spherical robot completing one cycle of peristaltic motion. Figure 7 (a) is the fully folded state of the spherical robot. In this state, the four spherical shells of the mechanism are completely folded up, and the overall shape is spherical. The drive motor (19) rotates forward, causing the first spherical shell (1), the second spherical shell (2), the third spherical shell (3), and the fourth spherical shell (4) to separate. The third spherical shell (3) and the fourth spherical shell (4) are lifted forward, as shown in the image. Figure 7 As shown in (b), the third spherical shell (3) and the fourth spherical shell (4) then tilt forward and contact the ground. At this time, the drive motor (19) reverses, causing the first spherical shell (1) and the second spherical shell (2) to retract inward, as shown in (b). Figure 7 As shown in (c), this causes the entire mechanism to creep forward.

[0056] A multi-loop spherical robot based on the Bricard mechanism can perform spin. For example... Figure 8 The image shows the spherical robot completing one cycle of spin. Figure 8 (a) is the fully folded state of the spherical robot. In this state, the four spherical shells of the mechanism are completely folded up, and the overall shape is spherical. The drive motor (19) rotates forward, causing the first spherical shell (1), the second spherical shell (2), the third spherical shell (3), and the fourth spherical shell (4) to separate. Figure 7 (b) The drive motor (19) then reverses to close the spherical shell and achieve spin, as shown. Figure 8 As shown in (b)-(c).

Claims

1. A multi-loop spherical robot based on the Bricard mechanism, comprising a first spherical shell, a second spherical shell, a third spherical shell, a fourth spherical shell, a first connecting seat, a second connecting seat, a third connecting seat, a fourth connecting seat, a fifth connecting seat, a sixth connecting seat, a first link, a second link, a third link, a fourth link, a fifth link, a sixth link, a seventh link, an eighth link, and a drive motor, wherein the connection method of the components constituting the mechanism is as follows: The single-hole surface and double-hole surface at the beginning of the first, second, third, fourth, sixth, and seventh links are connected by a revolute joint. Specifically, the single-hole surface at the beginning of the first link is connected to the double-hole surface at the beginning of the second link, the single-hole surface at the beginning of the second link is connected to the double-hole surface at the beginning of the seventh link, the single-hole surface at the beginning of the seventh link is connected to the double-hole surface at the beginning of the sixth link, the single-hole surface at the beginning of the sixth link is connected to the double-hole surface at the beginning of the third link, the single-hole surface at the beginning of the third link is connected to the double-hole surface at the beginning of the fourth link, and the single-hole surface at the beginning of the fourth link is connected to the double-hole surface at the beginning of the first link, thus forming a Bricard closed-loop structure. The tail end of the first link is connected to the first connecting seat via a revolute joint; the tail end of the second link is connected to the second connecting seat via a revolute joint; the tail end of the third link is connected to the fourth connecting seat via a revolute joint; the tail end of the fourth link is connected to the fifth link via a revolute joint; one end of the fifth link is connected to the third connecting seat via a revolute joint; the tail end of the sixth link is connected to the sixth connecting seat via a revolute joint; the tail end of the seventh link is connected to one end of the eighth link via a revolute joint; and one end of the eighth link is connected to the fifth connecting seat via a revolute joint. The first spherical shell is fixedly connected to the first connecting seat through bolt holes, the second spherical shell is fixedly connected to the second connecting seat through bolt holes, the third spherical shell is fixedly connected to the third and fourth connecting seats through bolt holes, and the fourth spherical shell is fixedly connected to the fifth and sixth connecting seats through bolt holes, forming a Bennett loop irregular structure. The two sides of the drive motor body are fixedly connected to the first spherical shell through bolt holes, and the two sides of the drive motor shaft are fixedly connected to the second spherical shell through bolt holes. The drive motor drives the first and second spherical shells connected by a rotating joint to move. The first spherical shell drives the fixedly connected first connecting seat to move, and the second spherical shell drives the fixedly connected second connecting seat to move. The first connecting seat drives the first connecting rod to move through the rotating joint, and the second connecting seat drives the second connecting rod to move through the rotating joint. The first connecting rod drives the fourth connecting rod to move through the rotating joint, and the second connecting rod drives the seventh connecting rod to move through the rotating joint. The fourth connecting rod drives the third and fifth connecting rods to move through the rotating joint, and the seventh connecting rod drives the sixth and eighth connecting rods to move through the rotating joint. The third connecting rod drives the fourth connecting seat to move through the rotating joint, and the fifth connecting rod drives the third connecting seat to move through the rotating joint. The sixth connecting rod drives the sixth connecting seat to move through the rotating joint, and the eighth connecting rod drives the fifth connecting seat to move through the rotating joint. The third and fourth connecting seats drive the fixedly connected third spherical shell to move, and the fifth and sixth connecting seats drive the fixedly connected fourth spherical shell to move.

2. The multi-loop spherical robot based on the Bricard mechanism as described in claim 1, wherein the component structure of the mechanism is as follows: The first spherical shell is a quarter sphere in shape. It has two bolt holes on its surface for fixed connection with the first connecting seat, three through holes for fixed connection with the front of the drive motor body, and four through holes for fixed connection with the back of the drive motor body. The second spherical shell is a quarter sphere in shape. It has two bolt holes on its surface for fixed connection with the second connecting seat, and five through holes for fixed connection with one side of the drive motor shaft. It also has five through holes for fixed connection with the other side of the drive motor shaft. The third spherical shell is a quarter sphere in shape, with two bolt holes on its surface for fixed connection with the third connecting seat, and two additional bolt holes for fixed connection with the fourth connecting seat. The fourth spherical shell is a quarter sphere in shape, with two bolt holes on its surface for fixed connection with the fifth connecting seat, and two additional bolt holes for fixed connection with the sixth connecting seat. The first connecting rod is T-shaped, and its tail end is connected to the first connecting seat through a rotating joint. Its head end is divided into a single-hole surface and a double-hole surface. The second connecting rod is T-shaped, with its tail end connected to the second connecting seat via a rotating joint, and its head end divided into a single-hole surface and a double-hole surface. The third link is T-shaped, and its tail end is connected to the fourth connecting seat through a rotating joint. Its head end is divided into a single-hole surface and a double-hole surface. The structure and external dimensions of the seventh link are the same as those of the third link. The fourth link is T-shaped, and its tail end is connected to the fifth link through a rotating joint. Its head end is divided into a single-hole surface and a double-hole surface. The structure and external dimensions of the sixth link are the same as those of the fourth link. The fifth link is a long straight rod, one end of which is connected to the third connecting seat through a rotating joint, and the other end is connected to the tail end of the fourth link through a rotating joint. The eighth link has the same structure and external dimensions as the fifth link. The lengths of the first, second, third, fourth, fifth, sixth, seventh, and eighth links shall not exceed the diameter of the spherical shell. The first, second, third, fourth, fifth, and sixth connecting seats are all identical in shape, with a large through hole at the top for connecting to each connecting rod via a rotating joint, and two small through holes at the bottom for fixing to each spherical shell.

3. A multi-loop spherical robot based on the Bricard mechanism as described in claim 1, characterized in that: Combining the unfolding characteristics of a spatially constrained mechanism with the flexible movement performance of a spherical robot, this robot possesses three gait modes—passive rolling, creeping, and spinning—by changing the unfolding position and landing area. The passive rolling gait utilizes the spherical shell for rolling motion, offering good flexibility and enabling rapid movement on flat surfaces. The creeping gait provides better ground stability and allows for precise linear movement with small strides. The spinning gait utilizes rotation around a central axis to change the angle of movement direction. These three gait modes can be switched according to different work requirements, enabling traversal of the work area.

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