A multi-degree-of-freedom end effector for a continuum robot

Abstract

This invention discloses a multi-degree-of-freedom end effector for a continuum robot, comprising a drive and tensioning component, a coupled continuum segment, an independent continuum segment, and a gripper. The drive and tensioning component, coupled continuum segment, independent continuum segment, and gripper are sequentially connected in series. Radial constraints are implemented according to corresponding structural notches, and axial fixation is achieved by applying preload through steel wire ropes. This invention uses a miniaturized purely mechanical handle for motion drive or is mounted at the end of a robotic arm for precise motor control of the actuator's movement. It possesses multiple degrees of freedom, allows for handheld operation, significantly reduces the application cost of the continuum robot, and the separation of the actuator from the drive unit facilitates later maintenance. The coupled motion control design enables the operation of multiple actuators in narrow passages, avoiding interference between multiple actuators while increasing their degrees of freedom.

Description

Technical Field

[0001] This invention relates to the field of continuum robot technology, and more specifically to a multi-degree-of-freedom end effector for a continuum robot. Background Technology

[0002] Traditional rigid robots face significant challenges in specific applications such as grasping complex and fragile objects, human-robot interaction, and operation in confined spaces due to their complex structure, limited flexibility, and low safety and adaptability.

[0003] Compared to pneumatic and hydraulic flexible actuators, flexible continuum robots, with their high degrees of freedom, flexible motion characteristics, and good stiffness retention, are gradually penetrating fields such as spacecraft maintenance, marine exploration, and medical intervention. In these applications, robots not only need to be able to reach target locations to explore internal conditions, but also need to maintain a certain degree of rigidity in specific positions to perform delicate operations such as fault repair, sample collection, or removal of diseased tissue in a stable posture.

[0004] However, multi-degree-of-freedom linearly driven continuum robots often require a large drive system and complex cable tensioning settings, which can easily lead to high prices and difficult maintenance. For example, patent application CN 116533285A uses a large screw drive system, which has a large overall size and high maintenance costs. Summary of the Invention

[0005] To overcome the above technical problems, the present invention aims to provide a multi-degree-of-freedom end effector for a continuous robot. This end effector is driven by a miniaturized purely mechanical handle or precisely controlled by a motor mounted at the end of a robotic arm. It possesses multiple degrees of freedom, can be handheld, significantly reducing the application cost of continuous robots. Furthermore, the design separating the actuator from the drive unit facilitates later maintenance. The coupled motion control design enables the operation of multiple actuators in narrow passages, avoiding interference between actuators while increasing their degrees of freedom.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A multi-degree-of-freedom continuum robot end effector includes a drive and tensioning component, a coupled continuum segment, an independent continuum segment, and a gripper; the drive and tensioning component, the coupled continuum segment, the independent continuum segment, and the gripper are connected in series in sequence, the radial constraint is implemented according to the corresponding notch in the structure, and the axial fixation is achieved by applying preload through a steel wire rope.

[0008] The driving and tensioning components include a driving frame, with two driving sheaves hinged to the driving frame by bolts. Slots and holes are provided at positions away from the coupling section continuum for mounting the driving sheaves; the gear portion of the driving sheaves meshes with the gear set of the power equipment.

[0009] Near the coupling section of the continuous body, there are four screw and nut pairs for independent tension adjustment of the four coupling section wire ropes that control the movement of the end clamp.

[0010] The drive frame has a cross-shaped structure near the coupling section continuum, which is used to place four tension bolt pairs.

[0011] One end of each of the four coupling section wire ropes is connected to the protruding lug structure of the drive frame, and the other end is connected to the corresponding hole in the independent section joint. The bottom of the tensioning bolt pair contacts the coupling section wire rope.

[0012] The drive frame is equipped with frame connection holes, which are connected to the drive source. There are two frame connection holes, which are respectively located at the front and rear ends of the drive frame where the drive wheel 11 is placed, and are distributed at an angle of 45 degrees, running through the entire drive frame.

[0013] The coupling segment continuum includes a middle coupling segment support tube, with the two ends of the coupling segment support tube being the coupling segment mating proximal end and the coupling segment mating distal end, respectively. The coupling segment mating proximal end is connected in series with the drive and tensioning components through multiple adapters, and the coupling segment mating distal end is connected in series with the independent segment connector through multiple adapters, thereby forming a complete coupling segment continuum.

[0014] The adapter is disc-shaped with protruding structures on the top and bottom surfaces, arranged in a crisscross pattern. Multiple adapters are provided and work together to form a flexible, movable part. The four small holes on the outside are the lateral channels of the adapter, and the middle one is the central channel of the adapter.

[0015] In the coupling section continuum, there are four coupling section steel wire ropes 5, evenly distributed at 90° in the four side channels of the adapter on the outer side of the adapter; one end of the four coupling section steel wire ropes is connected to the protruding lifting lug structure of the drive frame, and the other end is connected to the corresponding hole of the independent section connector.

[0016] The four coupled steel wire ropes are used to control the movement of the coupled continuous section during the motion process. The middle channel controls the movement of the independent continuous section. The four independent steel wire ropes and the steel wire rope of the end clamp and the sleeve on the steel wire rope are in different channels and do not come into contact with the four coupled steel wire ropes.

[0017] The independent segment continuum includes an independent segment connector and multiple adapters, which are connected in series. The adapters are arranged in the same direction and rotate 90 degrees axially each time.

[0018] The two ends of the independent section joint have the same structure as the adapter joint and are connected in series with the adapter joint. The middle part has an opening that connects the side channel of the adapter joint with the middle channel of the adapter joint. In this part, the independent section wire rope is transferred from the middle channel of the adapter joint to the side channel of the adapter joint.

[0019] In the independent section continuum, there are four thin independent steel wire ropes in the outer channel of the adapter, which are evenly distributed in the four lateral channels of the adapter. The independent steel wire ropes start from the drive spool, are wound on the drive spool, and end at the corresponding groove of the clamp. The middle channel has two steel wire ropes that control the opening and closing movement of the end clamp and the sleeves on the steel wire ropes.

[0020] The bottom of the clamp is consistent with the bottom of the adapter and is connected in series with the adapter. It is provided with a groove to hold the end of the independent section of wire rope.

[0021] The beneficial effects of this invention are:

[0022] This invention proposes a multi-degree-of-freedom end effector for a continuum robot, possessing a total of seven degrees of freedom. Two degrees of freedom for the independent continuum segments originate from the motion of two drive sheaves, which can be driven by motors or mechanical transmissions. The remaining five degrees of freedom are achieved through user operation, driving the relative motion of the tensioning component and the coupling support tube, thereby granting the end effector's end gripper the remaining five degrees of freedom. This design reduces the dependence of the continuum robot end effector's motion degrees of freedom on motors, lowering cost and size.

[0023] The coupling design of the coupled segment continuum allows the proximal and distal ends of the coupled segment continuum to move in the same direction, enabling multiple actuators to operate in coordination without interference within narrow channels. For example, it can be used to perform laparoscopic single-port multi-actuator surgery. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of an end effector for a multi-degree-of-freedom continuum robot proposed in this invention.

[0025] Figure 2 This is a schematic diagram of the structure of the drive and tensioning component of the present invention and the tensioning of the wire rope.

[0026] Figure 3 This is an exploded structural diagram of the present invention.

[0027] Figure 4 This is a schematic diagram of the wire rope routing of the present invention.

[0028] Figure 5 This is a schematic diagram of the independent section wiring and adapter of the present invention.

[0029] Figure 6 This is a schematic diagram of the adapter channel of the present invention.

[0030] Figure 7 This is a schematic diagram of the motion relationship of the present invention.

[0031] In the attached drawings, the following reference numerals are used: 1. Drive and tensioning components; 2. Coupled section continuous body; 3. Independent section continuous body; 4. Clamp; 5. Schematic diagram of the coupled section wire rope; 6. Schematic diagram of the independent section wire rope; 11. Drive reel; 12. Tensioning bolt pair; 21. Proximal end of the coupled section mating; 22. Coupled section support tube; 23. Distal end of the coupled section mating; 31. Independent section joint; 32. Adapter; 101. Drive frame; 102. Frame connecting hole; 321. Intermediate channel of the adapter; 322. Lateral channel of the adapter. r, Independent segment axial rotation input; r1, Independent segment axial rotation; a, Left drive wheel input motion; a1, Independent segment yaw axis deflection motion; b, Right drive wheel input motion; b1, Independent segment pitch axis deflection motion; R, Coupled segment axial rotation motion; c, Coupled segment yaw axis deflection input motion; c1, Coupled segment yaw axis deflection motion; d, Coupled segment pitch axis deflection input motion; d1, Coupled segment pitch axis deflection motion. Detailed Implementation

[0032] The present invention will be further described in detail below with reference to the embodiments.

[0033] See Figures 1 to 4 This invention presents the specific structure of a multi-degree-of-freedom continuum robot end effector. The actuator includes a drive and tensioning component 1, a coupled continuum segment 2, an independent continuum segment 3, and a gripper 4. The drive and tensioning component 1, the coupled continuum segment 2, the independent continuum segment 3, and the gripper 4 are connected in series sequentially. Radial constraints are achieved by installation according to corresponding structural notches, and axial fixation is achieved by applying preload through steel wire ropes.

[0034] The drive and tensioning component 1 is used to install the drive pulley 11 and to tension the steel wire rope 5 of the coupling section, and is also the main body for the user to control the movement of the coupling section continuous body 2.

[0035] The coupled segment continuum 2 is used to realize the five degrees of freedom of the end effector of the continuum robot by manual or external driving.

[0036] The independent segment continuum 3 is used to control the remaining two degrees of freedom of the end effector of the continuum robot through motor drive or mechanical transmission.

[0037] The clamp 4 is an example, used to operate on the target item, such as clamping, turning or other actions.

[0038] See Figure 2 In this embodiment, the driving and tensioning component 1 is mainly composed of a driving frame 101. Two driving pulleys 11 are hinged to the driving frame 101 via bolt pairs. Near the end of the coupling section continuous body 2, there are four tensioning bolt pairs 12, which can independently adjust the tension of the four steel wire ropes 5 controlling the movement of the coupling section continuous body 2. The frame connection hole 102 can be efficiently and simply bolted to the driving source, such as a motor or mechanical motion handle, making disassembly and maintenance convenient.

[0039] A slot and hole are provided at a position away from the coupling section continuum 2 to install the drive reel 11.

[0040] The drive frame 101 has a cross-shaped structure near the coupling section continuum 2 to accommodate four tension bolt pairs 12.

[0041] One end of each of the four coupling steel wire ropes 5 is connected to the protruding lifting lug structure of the drive frame 101, such as Figure 2 As shown, the other ends of the four coupling section steel wire ropes 5 are respectively connected to the corresponding holes in the independent section joint 31, as follows. Figure 5 As shown. The bottom of the tensioning bolt assembly 12 contacts the coupling section of the steel wire rope 5, as shown. Figure 2 As shown, tightening the tensioning bolt pair 12 can press down the coupling section wire rope 5, thereby independently tensioning each coupling section wire rope 5.

[0042] like Figure 2 As shown, there are two frame connection holes 102, which are specifically located at the front and rear ends of the drive frame 101 where the drive pulley 11 is placed. They are distributed at an angle of 45 degrees and run through the entire drive frame 101, and are used to connect with the power supply equipment by bolts.

[0043] The drive pulley 11 is located at the outermost end of the drive frame 101 and can be connected to the power supply equipment by bolts. The power equipment can be equipped with a gear set that meshes with the gear part of the drive pulley 11 to transmit power to the drive pulley 11.

[0044] See Figures 3 to 5 In this embodiment, the coupling segment continuum 2 is formed by the middle coupling segment support tube 22 cooperating with the coupling segment proximal end 21 and the coupling segment distal end 23 respectively; the coupling segment proximal end 21 is connected in series with the drive and tensioning component 1 through multiple adapters 32, and the coupling segment distal end 23 is connected in series with the independent segment connector 31 through multiple adapters 32, thereby forming a complete coupling segment continuum 2.

[0045] The specific shape and structure of adapter 32 are as follows: Figure 6As shown, the overall shape is disc-like, with protruding structures on the top and bottom surfaces, arranged in a crisscross pattern. Multiple protrusions can be combined to form a flexible, movable part. The four small holes on the outer side are the lateral channels 322 of the adapter, and the middle one is the central channel 321 of the adapter.

[0046] In the coupling section continuum 2, four coupling section steel wire ropes 5 are evenly distributed at 90° in the four lateral channels 322 outside the adapter 32; one end of each of the four coupling section steel wire ropes 5 is connected to the protruding lifting lug structure of the drive frame 101, such as... Figure 2 As shown, the other ends of the four coupling section steel wire ropes 5 are respectively connected to the corresponding holes in the independent section joint 31, as follows. Figure 5 As shown. Four coupling section steel wire ropes 5 are used to control the movement of the coupling section continuous body 2 during motion. The middle channel contains four independent section steel wire ropes 6 that control the movement of the independent section continuous body 3, and steel wire ropes with end clamps 4 and sleeves fitted onto them. Because they are in different channels, they do not contact the four coupling section steel wire ropes 5. When the four coupling section steel wire ropes 5 pass through the coupling section support pipe 22, they will rotate 180° from their original lateral channel 322 to the opposite lateral channel 322, as shown. Figure 4 Illustration. This design allows both ends of the coupled segment continuum 2 to swing in the same direction.

[0047] See Figures 3 to 6 In this embodiment, the independent segment continuous body 3 is composed of an independent segment connector 31 and multiple adapters 32 connected in series. The adapters 32 are arranged in the same direction and rotate 90 degrees axially each time, so that the independent segment continuous body 3 can have two degrees of freedom.

[0048] The two ends of the independent section connector 31 have the same structure as the adapter 32 and can be connected in series with the adapter 32. The middle part has an opening, which can connect the side channel 322 of the adapter with the middle channel 321 of the adapter. The independent section wire rope 6 can be transferred from the middle channel 321 of the adapter to the side channel 322 of the adapter in this part.

[0049] In the independent segment continuous body 3, there are four thin independent segment steel wire ropes 6 in the outer channel of the adapter 32, evenly distributed in the four lateral channels 322 of the adapter. The independent segment steel wire ropes 6 start from the drive spool 11, are wound on the drive spool 11, and end at the corresponding groove of the clamp 4, such as Figure 5 As shown. The intermediate channel 321 has two steel wire ropes and sleeves on the steel wire ropes for controlling the opening and closing movement of the end clamp 4.

[0050] This invention only describes the wiring arrangement of the steel wire rope that may be required to control the clamp 4. The steel wire rope can be replaced as needed, for example, by replacing the clamp at the end with an electric knife for cutting, or by replacing the steel wire rope with wires or other materials. The end clamp steel wire rope is always located in the intermediate channel 321 of the adapter to avoid being affected by the movement of other independent sections of steel wire rope 6 and coupled sections of steel wire rope 5.

[0051] The bottom of the chuck 4 is the same as the bottom of the adapter 32, and can be connected in series with the adapter 32. It is provided with a groove to place the end of the independent section of wire rope 6.

[0052] This invention only describes the connection form and movement of the chuck 4; the opening and closing design of the chuck is not within the scope of this invention.

[0053] The working principle of the actuator of this invention is as follows:

[0054] The end gripper of this invention has a total of seven degrees of freedom of movement, such as... Figure 7 As shown. When the coupling section support tube 22 is radially constrained in a narrow channel, the user can manually drive and tension the component 1 to move back and forth along the axial direction of the coupling section support tube 22, possessing one degree of freedom. When the user manually drives and tensions the component 1 to perform an independent section axial rotation input r, since each coupling section wire rope 5 of the coupling section continuum 2 is independent, the independent section axial rotation input r will be transmitted to the independent section joint 31, thereby realizing the independent section axial rotation r1, possessing one rotational degree of freedom.

[0055] The coupled section continuum 2 has three degrees of freedom. The operator can use a handheld actuator to achieve axial rotation R around the coupled section support tube 22, thus achieving one degree of freedom. When the operator manually inputs the yaw axis deflection c and pitch axis deflection d of the drive and tensioning component 1, the unidirectional routing design of the coupled section wire rope 5 of the coupled section continuum 2 causes the independent section continuum 3 to move in the same direction as the drive and tensioning component 1, thereby achieving yaw axis deflection c1 and pitch axis deflection d1, achieving two degrees of freedom. In narrow passages, when multiple actuators operate simultaneously, simply offsetting the actuators from the centerline avoids interference between the ends and ends of multiple actuators.

[0056] The movement of the drive sheave 11 is controlled by a motor or power transmission mechanism, which in turn controls the two degrees of freedom of the independent continuous section 3. The two drive sheaves 11 within the drive and tensioning component 1 respectively perform left drive sheave input motion a and right drive sheave input motion b, driving the movement of the independent section wire rope 6, thereby controlling the independent section yaw axis deflection and independent section pitch axis deflection of the independent continuous section 3. The gear portion of the drive sheave 11 is used to connect to the drive source, such as a motor or mechanical motion handle, via a simple and efficient bolt connection, facilitating disassembly and maintenance.

[0057] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A multi-degree-of-freedom end effector for a continuum robot, characterized in that, It includes a drive and tensioning component (1), a coupling section continuum (2), an independent section continuum (3), and a clamp (4); The drive and tensioning component (1), the coupling section continuum (2), the independent section continuum (3) and the clamp (4) are connected in series in sequence. The radial constraint is achieved by installing according to the corresponding gap in the structure. The axial fixation is achieved by applying pre-tightening force through the wire rope. The coupling segment continuum (2) includes a middle coupling segment support tube (22), with the two ends of the coupling segment support tube (22) being the coupling segment mating proximal end (21) and the coupling segment mating distal end (23), respectively. The coupling segment mating proximal end (21) is connected in series with the driving and tensioning component (1) through multiple adapters (32), and the coupling segment mating distal end (23) is connected in series with the independent segment connector (31) through multiple adapters (32), thereby forming a complete coupling segment continuum (2). The independent segment continuum (3) includes an independent segment connector (31) and multiple adapters (32), which are connected in series; the adapters (32) are arranged in the same direction and rotate 90 degrees axially each time. The two ends of the independent section connector (31) are identical to those of the adapter (32) and are connected in series with the adapter (32). The middle part has an opening that connects the adapter side channel (322) with the adapter middle channel (321). In this part, the independent section wire rope (6) is transferred from the adapter middle channel (321) to the adapter side channel (322).

2. The end effector for a multi-degree-of-freedom continuum robot according to claim 1, characterized in that, The drive and tensioning component (1) includes a drive frame (101), two drive wheels (11) are hinged to the drive frame (101) by bolts, and slots and holes are provided at positions away from the coupling section continuum (2) for mounting the drive wheels (11). The gear part of the drive wheels (11) meshes with the gear set of the power equipment. There are four screw and nut pairs (12) near the coupling section continuum (2) for independent tension adjustment of the four coupling section wire ropes (5) to control the movement of the end clamp (4).

3. The end effector for a multi-degree-of-freedom continuum robot according to claim 2, characterized in that, The drive frame (101) has a cross-shaped structure near the coupling section continuum (2) for placing four tension bolt pairs (12). One end of each of the four coupling section wire ropes (5) is connected to the protruding lug structure of the drive frame (101), and the other end is connected to the corresponding hole of the independent section connector (31). The bottom of the tension bolt pair (12) contacts the coupling section wire rope (5). The drive frame (101) is equipped with a frame connection hole (102), which is connected to the drive source. There are two frame connection holes (102), which are respectively located at the front and rear ends of the drive frame (101) where the drive spool (11) is placed, and are distributed at an angle of 45 degrees, running through the entire drive frame (101).

4. The end effector for a multi-degree-of-freedom continuum robot according to claim 1, characterized in that, The adapter (32) is generally disc-shaped with protruding structures on the top and bottom surfaces, arranged in a cross pattern. Multiple adapters (32) are provided and cooperate with each other to form a flexible and movable part. The four small holes on the outside are the side channels (322) of the adapter, and the middle one is the middle channel (321) of the adapter.

5. The end effector for a multi-degree-of-freedom continuum robot according to claim 4, characterized in that, In the coupling section continuum (2), there are four coupling section steel wire ropes (5) on the outer side channel (322) of the adapter (32), which are evenly distributed at 90° in the four side channels (322) of the adapter; one end of the four coupling section steel wire ropes (5) is connected to the protruding lug structure of the drive frame (101), and the other end is connected to the corresponding hole of the independent section connector (31); The four coupled section wire ropes (5) are used to control the movement of the coupled section continuous body (2) during the movement. The middle channel (321) controls the movement of the independent section continuous body (3). The four independent section wire ropes (6) and the wire ropes of the end clamp (4) and the sleeves on the wire ropes are in different channels and do not contact the four coupled section wire ropes (5).

6. The end effector for a multi-degree-of-freedom continuum robot according to claim 1, characterized in that, In the independent segment continuous (3), there are four thin independent segment steel wire ropes (6) on the outer channel of the adapter (32), which are evenly distributed in the four lateral channels (322) of the adapter. The independent segment steel wire rope (6) starts from the drive spool (11), is wound on the drive spool (11), and ends at the corresponding groove of the clamp (4). The middle channel (321) has two steel wire ropes that control the opening and closing movement of the end clamp (4) and the sleeves on the steel wire ropes.

7. The end effector for a multi-degree-of-freedom continuum robot according to claim 6, characterized in that, The bottom of the clamp (4) is consistent with the bottom of the adapter (32) and is connected in series with the adapter (32). It is provided with a groove to place the end of the independent section of wire rope (6).

Images