End effector for robotic system

Abstract

The invention provides an end effector for a robotic system. In one embodiment, the end effector for a robotic system comprises: a) a first member; b) a second member comprising: i) two flexible structures, each of said flexible structures comprising a live hinge; ii) a rigid bottom column for connecting a traction cable; i ii) a pivot point for contact with the first member; the second component is arranged in the first component, the second component can be driven to move at the pivot point by pulling the pulling cable, and meanwhile the two flexible structures are bent at the movable hinge.

Description

Technical Field

[0001] The present invention generally relates to end effectors for robotic systems, and more particularly to a flexible gripper for a robotic arm. Background Art

[0002] Gastric cancer and colorectal cancer are prevalent globally. These cancers are also the leading causes of cancer death worldwide. In fact, minimally invasive surgery has been widely used to evaluate diseases and injuries due to the absence of large incisions. Among them, endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) are established methods for removing precancerous lesions and early cancers in the gastrointestinal tract. These procedures are all performed using flexible endoscopes, enabling faster patient recovery and less pain.

[0003] With the rapid development of endoscopic surgery platforms in recent years, the development of end effectors with joint functions for this new type of handheld robotic tool has become increasingly important in the emerging field of medical robotics. For existing handheld designs, it is difficult to perform resection operations at the fundus of the stomach because the housing of the end effector obstructs the retroreflection (J-shaped bend) of the cannula. In addition, due to the particularity of the working environment, there are significant limitations in the geometry and size of the end effector. Developing a reliable endoscopic robotic arm has been a long-standing challenge.

[0004] The flexible gripper described in the present invention has excellent mechanical properties, including flexible columns on the jaws. The flexible columns are an elastic structure that can provide the required flexibility during elastic deformation. This design enables it to operate in the X-Y plane and precisely grasp the target object. In addition, the passive flexible underactuated structure enables the gripper to adapt to irregular objects with arbitrary shapes and surface characteristics. Since the jaws can grasp delicate objects without damaging tissues, the safety during the surgical process is improved.

[0005] The purpose of the underactuated structure is to optimize the gripper structure. When driving the opening and closing movement of the gripper, more degrees of freedom are controlled by fewer active inputs. Another purpose of the underactuated structure is to simplify the control algorithm by reducing the control variables. In addition to reducing the complexity of the required control, this design also reduces the rigidity of the robotic arm during bending. Summary of the Invention

[0006] The present invention provides an end effector for a robotic system. In one embodiment, the end effector for the robotic system includes: a) a first member; b) a second member, including: i) two flexible structures, each of the flexible structures including a living hinge; ii) a rigid bottom column for connecting a towing cable; iii) a pivot point for contacting the first member; the second member is disposed inside the first member, and pulling the towing cable can drive the second member to move at the pivot point while bending the two flexible structures at the living hinges. Description of the Drawings

[0007] Exemplary non-limiting embodiments of the present invention are described with reference to the accompanying drawings. The drawings are schematic illustrations and are generally not drawn to an exact scale. In different figures, the same or similar elements are labeled with the same reference numerals.

[0008] Figures 1A to 1G Various embodiments of the gripper structure for a robotic arm are shown. Detailed Description

[0009] The present invention relates to an end effector for a robotic system, and the end effector realizes the grasping of an object through the application of a flexible structure.

[0010] The present invention describes a structure of a flexible gripper, and the gripper includes a living hinge for an end effector of a robotic system. The structure of the flexible gripper is usually in a closed state, so it does not affect the rigidity of the robotic arm and the sleeve when the gripper grasps an object. The opening movement of the gripper can be controlled by adjusting the tension of the towing cable.

[0011] In one embodiment, the present invention provides a gripper structure for a robotic arm. The gripper structure includes an open end of a cylindrical housing and a flexible gripper. The jaws are connected to a flexible column and can safely grasp tissue. This device can be connected to a flexible robotic arm. This device adopts an underactuated design to reduce the number of towing cables required to drive the end effector and reduce the rigidity during the bending process.

[0012] The present invention provides a gripper structure for a robotic system. In one embodiment, the structure includes: a first member in a cylindrical shape, which serves as a platform for mounting the second member; two second members, each of the second members including at least one flexible segment that elastically deforms during the operation of the gripper; a rigid segment, which is connected to each flexible segment and does not intentionally deform during the operation of the gripper; the gripper is usually in a closed state; the gripper can be opened by pulling at least one cable connected to the rigid segment.

[0013] In one embodiment, the structure further includes at least one rotary joint for connecting the flexible section and the rigid section.

[0014] In one embodiment, the structure further includes a fixed anchor for fixing the cable to the rigid section.

[0015] In one embodiment, the opening angle of the gripper is proportional to the pulling force applied to the cable.

[0016] In one embodiment, the structure further includes a pivot point provided on the cylindrical member, and the pivot point coincides with the position of the rotary joint of the flexible section.

[0017] In one embodiment, the structure further includes a metal part that passes through the pivot point and the rotary joint to fix the positions of the members.

[0018] In one embodiment, the first member and the second member are made of a plastic.

[0019] In one embodiment, the second member is diamond-shaped.

[0020] In one embodiment, the aspect ratio and the length-to-thickness ratio of each flexible section are both greater than 1, and the thickness of the bottom rigid section is greater than the thickness of the flexible section.

[0021] In one embodiment, the first member is an open cylinder and has two identical tongues on a planar surface.

[0022] In one embodiment, the structure further includes a guiding member that contacts a groove on the bottom rigid section to limit the rotation angle.

[0023] In one embodiment, the flexible section includes a living hinge.

[0024] In one embodiment, the rigid section includes a groove.

[0025] The present invention provides an end effector for a robotic system. In one embodiment, the end effector for the robotic system includes: a) a first member; b) a second member, including: i) two flexible structures, each of the flexible structures including a living hinge; ii) a rigid bottom column for connecting a traction cable; iii) a pivot point in contact with the first member; the second member is disposed inside the first member, and pulling the traction cable can drive the second member to move at the pivot point while bending the two flexible structures at the living hinges.

[0026] In one embodiment, the first member includes a guiding member 110 that contacts a groove 109 on the rigid bottom column 105 to limit the rotation angle.

[0027] In one embodiment, the second member includes: a) a first jaw including one of the two flexible structures, the rigid bottom column, and a first rotating joint; b) a second jaw connected to the first jaw, including the other of the two flexible structures and a second rotating joint; the first rotating joint and the second rotating joint together form the pivot point.

[0028] In one embodiment, the first member includes a hole through which a pin is inserted and passes through the second member to form the pivot point.

[0029] In one embodiment, each of the two flexible structures includes a flexible column 104 and a top flexible section 107.

[0030] In one embodiment, the second member is in a rhombus shape; a) the top flexible section is in a hairpin shape and includes two ends; the upper flexible section is connected to the pivot point at one of the two ends and is connected to the flexible column at the other end; b) the flexible column includes two ends; the flexible column is connected to the rigid bottom column at one of the two ends and is connected to the top flexible section at the other end.

[0031] In one embodiment, the first member is an open cylinder and has two identical tongues.

[0032] In one embodiment, the living hinge is curved.

[0033] In one embodiment, the towing cable is connected to the rigid bottom column through a hollow metal piece and passes through the first member.

[0034] In one embodiment, the aspect ratio and the length-to-thickness ratio of each of the flexible structures are greater than 1, and the thickness of the rigid bottom column is greater than the thickness of each of the flexible structures.

[0035] The present invention provides a gripper structure for a robotic arm. In one embodiment, the gripper structure for a robotic arm is a gripping or retracting device for robotic endoscopic surgery, including: a first member, which is a cylindrical shell with an opening and has a hollow part 100 inside, such as Figure 1AAs shown; a second member, comprising two separable flexible structures 101, 102, a clamping section connecting the top and middle rotating joint 103, and a flexible column 104 connected to the rigid bottom column 105. Figure 1C Show the right jaw connected to the flexible column. Figure 1D Show the left jaw connected to the flexible column and positioned opposite the right jaw. The three separate parts are assembled together by a metal pin, and the pivot point 106 of the second member is located on the first member. A towing cable is fixed to the bottom column 105 by connecting to a fixed anchor and applies a pulling force to the rigid bottom column. The first member opens and closes according to the force applied through the towing cable, and the rigid bottom column 105 moves backward along the guidance of the first member and remains in contact during the process.

[0036] In one embodiment, the first member and the second member are made of a plastic.

[0037] In one embodiment, the second member is diamond-shaped and includes a top flexible section 107 connecting the middle rotating joint 103. The top flexible section is coupled to the rigid bottom column. Each of the flexible sections has a width determined by the material properties and a relatively small thickness, and the thickness of the rigid bottom column is greater than the thickness of the flexible section.

[0038] In one embodiment, the first member is an open cylinder and has two identical tongues 108 on the planar surface.

[0039] In one embodiment, the towing cable is fixed to the rigid bottom column 105 through a hollow metal piece and passes through the cylindrical housing.

[0040] In one embodiment, the flexible column includes a living hinge 111.

[0041] In one embodiment, the rigid bottom column includes a groove 109 with a curved surface.

[0042] In one embodiment, the rotating joint is a toroidal structure.

[0043] In one embodiment, the living hinge 111 is curved.

[0044] In one embodiment, the tongue includes a guiding component 110 that contacts the groove on the rigid bottom column 105 to limit the rotation angle.

Claims

1. An end effector for a robotic system, characterized in that: The end effector includes: a. A first member; b. A second member, including: i. Two flexible structures, each of the flexible structures including a living hinge; ii. A rigid bottom columnar member for connecting a towing cable; iii. A pivot point in contact with the first member; The second member is disposed inside the first member. Pulling the towing cable can drive the second member to move at the pivot point, and at the same time cause the two flexible structures to bend at the living hinge.

2. The end effector according to claim 1, characterized in that: The first member includes a guiding member (110), and the guiding member contacts a groove (109) on the rigid bottom columnar member (105) to limit the rotation angle.

3. The end effector according to claim 1, characterized in that: The second member includes: a. A first jaw, including one of the two flexible structures, the rigid bottom columnar member, and a first rotating joint; b. A second jaw connected to the first jaw, including the other of the two flexible structures and a second rotating joint; The first rotating joint and the second rotating joint are combined to form the pivot point.

4. The end effector according to claim 1, wherein: The first member includes a hole, and a pin is inserted through the second member through the hole to form the pivot point.

5. The end effector according to claim 1, characterized in that: Each of the two flexible structures includes a flexible columnar member (104) and a top flexible section (107).

6. The end effector according to claim 5, characterized in that: The second member is in a rhombus shape; a. The top flexible section is in a hairpin shape and includes two ends; the upper flexible section is connected to the pivot point at one of the two ends and is connected to the flexible columnar member at the other end; b. The flexible columnar member includes two ends; the flexible columnar member is connected to the rigid bottom columnar member at one of the two ends and is connected to the top flexible section at the other end.

7. The end effector according to claim 1, wherein: The first member is an open cylinder and has two identical tongues.

8. The end effector according to claim 1, wherein: The living hinge is curved.

9. The end effector according to claim 1, wherein: The towing cable is connected to the rigid bottom columnar member through a hollow metal piece and passes through the first member.

10. The end effector according to claim 1, wherein: The aspect ratio and the length-to-thickness ratio of each of the flexible structures are greater than 1, and the thickness of the rigid bottom columnar member is greater than the thickness of each of the flexible structures.

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