Rope-driven pleated flexible gripper with end adsorption function and kinematics modeling analysis method thereof

Abstract

The application discloses a rope-driven pleated flexible gripper with a terminal adsorption function and a kinematic modeling analysis method thereof, the gripper has three fingers, and is more easy to adapt to irregular-shaped objects; through cooperation of the finger gripping and the terminal adsorption device, flexible gripping of various objects in various environments is realized, and problems such as insecure gripping, difficulty in gripping large or small objects, and difficulty in gripping in a narrow or deep cavity environment are effectively solved. Moreover, through kinematic modeling analysis, precise control of the gripping motion of the flexible gripper can be realized, and high efficiency of the flexible gripper is ensured.

Description

Technical Field

[0001] This invention belongs to the field of robotics technology, specifically relating to a rope-driven pleated flexible gripper with end-effector adsorption function and its kinematic modeling and analysis method. Background Technology

[0002] With the rapid development of science and technology, robotics has been widely applied in various fields. However, traditional rigid robots are typically used in specific tasks and environments, and their low flexibility and compliance may lead to damage or jamming in confined spaces or unstructured environments, resulting in task failure. In contrast, the softness and high adaptability of flexible robots make them perform well in complex, narrow, or irregular environments. Flexible grippers, as an important branch of flexible robotics technology, have unique advantages and broad research value.

[0003] Table 1 Comparison of the advantages and disadvantages of flexible grippers with different driving methods

[0004]

[0005] Based on the various types of flexible grippers in Table 1, the rope-driven flexible gripper is the best choice for deep cavities or unstructured environments due to its lightweight, high load capacity, and higher positioning accuracy.

[0006] The current rope-driven flexible gripper mainly has the following problems:

[0007] 1. Due to the properties of flexible materials such as silicone, the rope-driven gripper is not secure when performing bending and grasping tasks. In addition, flexible grippers are mostly used to grasp fragile objects, and they are more likely to be damaged if they slide and fall.

[0008] 2. When the volume of the object being grasped exceeds the linear length limit of the flexible gripper, it is difficult for the flexible gripper to envelop and grasp it; when the volume of the object being grasped is too small, it is difficult for the flexible gripper to apply sufficient contact area and force, making it difficult to achieve precise grasping.

[0009] 3. Existing rope-driven flexible grippers mostly rely on bending and grasping to complete grasping tasks. In confined or deep cavity environments, the flexible fingers are difficult to bend, making it difficult to grasp objects. Summary of the Invention

[0010] This invention addresses the challenges of current rope-driven flexible grippers, such as unstable gripping, easy slippage, difficulty in grasping large or small objects, and difficulty in bending and gripping in narrow or deep cavities. It independently designs a rope-driven pleated flexible gripper with end-capture adsorption function and uses a constant curvature modeling method to perform kinematic modeling and analysis on the flexible gripper to achieve precise control of the gripper's grasping motion.

[0011] The flexible gripper includes three fingers, making it easier to adapt to irregularly shaped objects. The three fingers have an identical structure and are fixed equidistantly below the control box. Each finger includes a finger body, a finger base, a servo motor, and a servo disc. The finger body is fixed below the finger base, and the servo motor and servo disc are fixed equidistantly on the finger base, with the servo motor and servo disc corresponding to each other. The finger body includes a silicone shell and four evenly distributed fishing lines. The silicone shell has a pleated texture. An adsorption device is provided at the end of the silicone shell away from the finger base for grasping objects by adsorption. One end of each fishing line is fixed to the corresponding servo disc, and the other end of the fishing line is fixed to the far end of the silicone shell. The servo motor pulls the fishing line in the silicone shell, causing the flexible finger to deflect and bend.

[0012] The silicone shell is a hollow structure made of silicone injection, with a spring frame inside the cavity to prevent excessive local bending when the finger body undergoes continuous deformation. The adsorption device specifically includes a suction cup and a suction cup fixing component; the control box contains an air pump and a microcontroller; an air tube passes through the inner cavity of the spring frame, connecting the air pump and the suction cup; the microcontroller is used to drive the air pump.

[0013] The finger body contains four fishing lines, which are connected to the servo motor and servo disc respectively. The microcontroller drives the servo motor to rotate, which in turn drives the servo disc to rotate and change the relative length of the fishing lines, thereby controlling the deflection direction and bending angle of the flexible finger.

[0014] The three fingers have the same structural design and the same motion principle. Taking a flexible finger as an example, kinematic modeling analysis is performed. By performing forward and inverse kinematic analysis on the flexible finger, the microcontroller in the control box drives the servo motor to rotate, which drives the servo disk to rotate and change the relative length of the four fishing lines. This enables the control of the deflection direction and bending angle of the flexible finger, thereby improving the accuracy of the grasping action of the flexible gripper.

[0015] This flexible gripper has three gripping modes, which can adapt to a variety of working environments and grasp objects of different sizes and shapes.

[0016] Grasping Mode 1: When the object to be grasped is of moderate size and can be enveloped by the flexible gripper, the microcontroller drives the servo motor to rotate, which in turn drives the servo disc to rotate and change the relative length of the fishing line. The fishing line acts as a tendon to drive the three flexible fingers to bend and envelop the object to be grasped, thus completing the grasping task. At the same time, the folded texture on the surface of the fingers makes the grasping more stable.

[0017] Grasping Mode Two: When the object's size exceeds the linear length limit of the flexible gripper, the grasping task cannot be completed by relying solely on the bending envelope of the fingers. In this case, the microcontroller drives an air pump, utilizing the suction cup at the end of the flexible gripper to complete the grasping task for the larger object. When the object's size is too small, making it difficult for the bending envelope of the fingers to apply sufficient contact area and force, the microcontroller drives an air pump, utilizing the suction cup of the flexible gripper to complete the grasping task for the smaller object.

[0018] Grasping Mode 3: When facing a confined or deep working environment, the entire flexible gripper cannot fully enter the working environment, and the bending and grasping of the fingers are restricted. In this case, single-finger actuation is used. After a single finger enters the working environment, the microcontroller drives the air pump, and the suction cup at the fingertip completes the grasping task.

[0019] This flexible gripper can efficiently grasp various types of objects in a variety of environments. When bending and gripping, the pleated texture on the surface of the flexible fingers can increase the contact area between the fingers and the surface of the object being grasped, improve friction, reduce the risk of the object slipping, and make the gripper more stable. At the same time, due to the softness and variability of the pleated texture, the flexible gripper can better adapt to objects of different shapes, making it easier to grasp a variety of objects.

[0020] In summary, due to the adoption of this technical solution, the beneficial effects of this invention are as follows: The rope-driven pleated flexible gripper with end-adsorption function and the kinematic modeling and analysis method proposed in this invention can effectively solve problems such as weak grip, difficulty in grasping large or small objects, and difficulty in grasping in narrow or deep cavity environments. It has a wide range of applications, high work efficiency, good safety and stability, and has high application value. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the rope-driven pleated flexible gripper with end adsorption function described in this invention;

[0022] Figure 2 This is a schematic diagram of the structure of one finger of the flexible claw described in this invention;

[0023] Figure 3 This is a structural schematic diagram of the finger body and its cross-section of the flexible claw described in this invention;

[0024] Figure 4 This is a schematic diagram of the control box of the flexible gripper described in this invention;

[0025] Figure 5 This is a schematic diagram of the flexible gripper grasping an object of moderate size according to the present invention;

[0026] Figure 6This is a schematic diagram of the flexible gripper grasping a large object according to the present invention.

[0027] Figure 7 This is a schematic diagram of the flexible gripper grasping a small object according to the present invention.

[0028] Figure 8 This is a schematic diagram of the flexible gripper described in this invention in a narrow or vertically deep cavity environment.

[0029] Figure 9 This is a schematic diagram of the flexible gripper described in this invention in a narrow or curved deep cavity environment.

[0030] Figure 10 This is a schematic diagram of the constant curvature analysis of the fingers of the flexible claw described in this invention;

[0031] Figure 11 This is a top view of the finger section of the flexible claw described in this invention;

[0032] Figure 12 This is a cross-sectional view of the finger deflection surface of the flexible claw described in this invention;

[0033] Figure 13 This is a flowchart illustrating the specific process of the flexible gripper described in this invention grasping an object.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Finger 1; 2. Finger 2; 3. Finger 3; 4. Control box; 5. Object of moderate size; 6. Object of relatively large size; 7. Object of relatively small size; 11. Finger body; 12. Finger base; 13. Servo motor; 14. Servo disc; 111. Air tube; 112. Fishing line; 113. Spring frame; 114. Suction cup; 115. Suction cup fixing piece; 116. Silicone shell; 1161. Wrinkled texture; 41. Air pump; 42. Microcontroller. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Example 1

[0038] like Figure 1-4As shown, the rope-driven pleated flexible gripper with end-adhesion function includes finger 1, finger 2, finger 3, and control box 4. Control box 4 contains three air pumps 41 and one microcontroller 42. The three fingers are equidistantly fixed below control box 4, and the three fingers have identical structures. Therefore, taking finger 1 as an example, finger 1 mainly includes a finger body 11, a finger base 12, servo motors 13, and servo discs 14. The finger body 11 is fixed below the finger base 12, and the four servo motors 13 and four servo discs 14 are equidistantly fixed on the finger base.

[0039] The finger body 11 includes an air tube 111, a fishing line 112, a spring frame 113, an adsorption device, a silicone shell 116, and a textured surface 1161. The silicone shell 116 is made of silicone injection, ensuring the softness of the finger. The silicone textured surface effectively overcomes the problem of weak grip caused by low friction between the flexible material and the object surface. The spring frame 113 ensures continuous deformation of the finger body 11 while effectively avoiding stress concentration and unpredictable shape caused by excessive local bending angles. The adsorption device is located at the end of the finger body 11 and includes a suction cup 114 and a suction cup fixing member 115. The suction cup 114 is connected to the end of the silicone shell 116 through the suction cup fixing member 115. The air tube 111 passes through the inner cavity of the spring frame 113 and connects the air pump 41 to the suction cup 114. The microcontroller 42 drives the air pump to realize the adsorption and release of the suction cup 114 on the object. Each flexible finger consists of four fishing lines 112 evenly embedded in a silicone shell 116. One end of each fishing line 112 is fixed to a rudder disc 14, and the other end is fixed to the end of the silicone shell 116 away from the finger's base 12. Rotating the rudder disc 14 changes the relative length of the fishing lines 112. The servo motor 13 drives the rudder disc 14 to rotate and pull the fishing lines 112 embedded in the silicone shell 116, thereby controlling the direction of deflection and the angle of bending of the flexible finger, enabling the flexible finger to achieve 360° angle changes.

[0040] Example 2

[0041] Based on Example 1, this example provides a method for kinematic modeling and analysis of a rope-driven pleated flexible gripper with end-adhesion function.

[0042] Kinematic modeling of flexible bodies allows for a better understanding and control of their behavior, which is crucial for technological innovation and scientific research. Table 2 compares the basic principles, advantages, and disadvantages of different kinematic modeling methods.

[0043] Table 2 Comparison of the basic principles, advantages and disadvantages of different kinematic modeling methods

[0044]

[0045]

[0046] Experimental observations of a rope-driven, pleated flexible claw with end-adhesion revealed that the curvature of each part of the flexible finger is basically the same when it bends, meaning the bending of the flexible finger essentially presents an arc. This invention avoids overly complex deformations and nonlinear behaviors; the use of constant curvature modeling simplifies calculations while providing a reasonable analysis.

[0047] Based on this observation, the following hypothesis is proposed:

[0048] (1) Flexible fingers bend at a constant curvature;

[0049] (2) Flexible fingers ignore shape changes caused by gravity during bending;

[0050] (3) The folded texture does not affect the movement of the flexible fingers, and the shape of the fingers is simplified to a cylinder.

[0051] Based on the above assumptions, the shape of the flexible finger body 11 is simplified to a cylinder. The center point of the finger body 11 connecting to the finger base 12 is set as the base point O, and an XYZ coordinate system is established with base point O as the origin. The following pose parameters are proposed to describe the flexible finger: the angle φ between the deflection surface and the XOZ plane; the constant curvature bending radius r of the deflection surface; and the central angle θ of the deflection surface. The deflection surface is as follows... Figure 10 The figure shows the plane where the base point O and the center point O1 of the fingertip are located after bending.

[0052] Based on this, constant curvature kinematic modeling of the flexible finger is performed, and the mapping relationship between the rotation angle of the steering wheel 14 and the three pose parameters of the finger body 11 is obtained through forward kinematic analysis and inverse kinematic analysis.

[0053] like Figure 10 As shown, assuming the initial length of the fishing line in the flexible finger is L, the microcontroller 42 drives the servo motor 13, which in turn rotates the servo disc 14. After the finger bends and deflects, the change in the length of the fishing line 112 is q. i (i = 1, 2, 3, 4), where i represents the i-th fishing line, and the current length of the fishing line in the flexible finger is l. i The cross-sectional radius of the flexible finger's core is R. Based on the above motion process, a kinematic analysis of the flexible finger is performed.

[0054] First, we perform a forward kinematics analysis. The current length of the fishing line is l. i .

[0055] l i =Lq i (1)

[0056] Meanwhile, the length l of the central arc of the flexible finger and the change q of the central arc can be respectively determined by the length l of the four fishing lines 112. i With change q i To obtain.

[0057]

[0058] Depend on Figure 11 , 12 The pose parameters φ, r, θ of the flexible finger and the current length l of the fishing line 112 in the flexible finger can be derived. i The relationship between them.

[0059]

[0060] From formulas (1), (2), and (3), we can obtain the changes q of the pose parameters φ, r, and θ of the flexible finger with respect to the fishing line 112. i The relationship between them.

[0061]

[0062]

[0063]

[0064] The change q of the fishing line 112 i Rotation angle ξ of rudder 14 i The relationship between them is shown in formula (7).

[0065] q i =ξ i R d (7)

[0066] Where R d Let ξ be the radius of rudder 14. i The range of values ​​is Substituting formula (7) into formulas (4), (5), and (6) yields the mapping relationship between the rotation angle of the rudder 14 and the three pose parameters of the flexible finger.

[0067]

[0068]

[0069]

[0070] In formula 10 The above-mentioned position and posture of the flexible finger after motion transformation are obtained from the rotation angle of the rudder 14, thus completing the forward kinematic analysis of the flexible finger.

[0071] Next, inverse kinematics analysis is performed, decomposing the motion of the flexible finger into two parts: first, the flexible finger bends around the y-axis by an angle θ, and then rotates around the z-axis by an angle φ. Based on these two motion transformations, the distance from the base point O of the flexible finger to the transformed distal end point p(p) can be obtained. x ,p y ,p z The homogeneous transformation matrix T of ).

[0072]

[0073] The end point p(p) of the flexible finger after bending and deflection x ,p y ,p z The coordinate system at point T is O1-x1y1z1. p Let be the pose matrix of the endpoint, (α) x ,α y ,α z ) T ,(β x ,β y ,β z ) T ,(γ x ,γ y ,γ z ) T These represent the direction vectors of the x1, y1, and z1 axes of the end point coordinate system in the base coordinate system, respectively.

[0074]

[0075] Let T p =T, we can get,

[0076]

[0077] θ=arccosγ z (14)

[0078]

[0079] Substituting formulas (13), (14), and (15) into formulas (1), (3), and (7), the rotation angle of each rudder disk 14 can be obtained based on the pose of the end point. Thus, the rotation angle of the corresponding rudder disk 14 is obtained based on the end pose of the flexible finger, thereby completing the inverse kinematics analysis of the flexible finger.

[0080] Based on the forward and inverse kinematic analysis of the flexible fingers, precise control of the grasping motion of the flexible gripper described in this invention can be achieved, ensuring the high efficiency and accuracy of the flexible gripper's operation.

[0081] Example 3

[0082] Based on Examples 1 and 2, this example provides a grasping method for a rope-driven pleated flexible gripper with end-adhesion function.

[0083] This flexible gripper has three gripping modes, adaptable to various working environments, and can grasp objects of different sizes and shapes, such as... Figure 12 As shown.

[0084] Grasping Mode 1: When the object to be grasped is of moderate size and can be enveloped by the flexible gripper, the microcontroller 42 drives the servo motor 13 to rotate, causing the servo disc 14 to rotate, thereby changing the relative length of the fishing line 112. The fishing line 112 acts as a tendon, driving the three flexible fingers to bend and envelop the object to be grasped, completing the grasping task. At the same time, the folded texture 1161 on the surface of the fingers makes the grasping more stable. Figure 5 As shown.

[0085] Grasping Mode Two: When the object's size exceeds the linear length limit of the flexible gripper, grasping cannot be accomplished by relying solely on the bending and enveloping of the fingers. In this case, the microcontroller 42 drives the air pump 41, utilizing the suction cup 114 at the end of the flexible gripper to complete the grasping task of the larger object, such as... Figure 6 As shown. When the object is too small, it is difficult for the fingers to apply sufficient contact area and force. In this case, the microcontroller 42 drives the air pump 41, and the suction cup 114 of the flexible gripper completes the task of grasping the small object. Figure 7 As shown.

[0086] Grasping Mode 3: When facing a confined or deep working environment, the entire flexible gripper cannot fully enter the working environment, and the bending and grasping of the fingers are restricted. In this case, single-finger actuation is used. For vertical deep cavity environments, after a single finger enters the working environment, the microcontroller 42 drives the air pump 41, and the suction cup 114 at the fingertip completes the grasping task. Figure 8 As shown. For curved deep cavity environments, the microcontroller 42 determines the rotation angle of the servo disk 14 based on the end position and curvature of the cavity through kinematic modeling analysis. The microcontroller 42 drives the servo motor 13 to rotate, thereby rotating the servo disk 14 by a predetermined angle to ensure that the finger can smoothly enter the cavity and that the suction cup 114 at the fingertip is directly opposite the bottom of the cavity. Then, the microcontroller 42 drives the air pump 41 to complete the grasping task through the suction function of the fingertip suction cup 114. Figure 9 As shown.

[0087] Combining these three gripping modes, this flexible gripper can efficiently complete the gripping task of various types of objects in various environments. When bending and gripping, the pleated texture on the surface of the flexible fingers can increase the contact area between the fingers and the surface of the object being gripped, improve friction, reduce the risk of the object being gripped slipping, and make the gripping of the flexible gripper more stable. At the same time, due to the softness and variability of the pleated texture, the flexible gripper can better adapt to objects of different shapes, making it easier to grip diverse objects.

[0088] Furthermore, through kinematic modeling and forward and inverse kinematic analysis of the flexible finger, the microcontroller 42 can precisely drive the servo motor 13 to rotate, thereby controlling the rotation angle of the servo disc 14 and the end position of the flexible finger, achieving precise control of the grasping motion of the flexible gripper described in this invention, and ensuring the efficient and accurate operation of the flexible gripper.

[0089] Example 4

[0090] Based on Examples 1 to 3, this example provides a method for preparing a rope-driven pleated flexible gripper with end-adsorption function.

[0091] After thoroughly mixing equal amounts of Ecoflex 0050 silicone liquid A and liquid B, the mixture is poured into the designed finger mold. A spring is inserted into the soft cavity, and an air tube 111 passes through the center of the spring frame 113, connecting the air pump 41 and the suction cup 114. After the silicone has cured, the mold is removed to obtain a flexible finger. Finally, three flexible fingers are fixed equidistantly on the finger base 12. Each flexible finger is evenly pierced by four fishing lines 112, one end of which is fixed to the rudder 14. The rudder 14 rotates to change the relative length of the four fishing lines 112, thereby controlling the deflection direction and bending angle of the flexible finger. The spring frame 113 ensures continuous deformation of the flexible finger while effectively avoiding stress concentration and unpredictable shape caused by excessive local bending angles. The outer silicone 116 wraps around the spring, ensuring the softness of the finger. The silicone pleated texture 1161 on the surface effectively overcomes the problem of weak grip caused by the low friction between the flexible material and the object surface. At the same time, the suction cup 114 at the end of the finger effectively solves the problem of the flexible finger having difficulty grasping objects that are too large or too small.

[0092] Although this disclosure has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0093] The disclosed embodiments are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A kinematic modeling and analysis method for a rope-driven, folded, flexible gripper with end-capture adsorption function, characterized in that: The flexible gripper includes finger one (1), finger two (2), finger three (3), and a control box (4). The three fingers have the same structure and are fixed at equal intervals below the control box (4). Each finger includes a finger body (11), a finger base (12), four servo motors (13), and four servo discs (14). The finger body (11) is fixed below the finger base (12), and the four servo motors (13) and four servo discs (14) are fixed at equal intervals on the finger base (12). The machine (13) and the steering wheel (14) are correspondingly set; the finger body (11) includes a silicone shell (116) and four evenly distributed fishing lines (112); the silicone shell (116) is provided with a pleated texture (1161); the end of the silicone shell (116) away from the finger base (12) is provided with an adsorption device for grasping objects by adsorption; one end of each fishing line (112) is fixed to the corresponding steering wheel (14), and the other end of the fishing line (112) is fixed to the steering wheel (14). The end is fixed to the far end of the silicone shell (116). The servo motor (13) pulls the fishing line (112) in the silicone shell (116) to make the flexible finger deflect and bend. The silicone shell (116) is a hollow structure with a spring skeleton (113) in the cavity. The spring skeleton (113) is used to prevent excessive local bending when the finger body (11) deforms continuously. The adsorption device specifically includes a suction cup (114) and a suction cup fixing part (115). The control box (4) The device contains an air pump (41) and a microcontroller (42); an air tube (111) passes through the inner cavity of the spring frame (113) and connects the air pump (41) and the suction cup (114); the microcontroller (42) is used to drive the air pump (41); the silicone shell (116) is made of silicone; the microcontroller (42) drives the servo motor (13) to rotate, which drives the servo disc (14) to rotate and change the relative length of the fishing line (112), thereby controlling the deflection direction and bending angle of the flexible finger. The kinematic modeling and analysis method includes simplifying the shape of the finger body (11) into a cylinder, and setting the center point of the finger body (11) connected to the finger base (12) as the base point. , based on An XYZ coordinate system is established with the origin, and a constant curvature kinematic model is performed on the flexible finger. The mapping relationship between the rotation angle of the steering wheel (14) and the pose parameters of the finger body (11) is obtained through forward kinematic analysis and inverse kinematic analysis. The pose parameters include the angle between the deflection surface and the XOZ surface. The constant curvature bending radius of the deflection surface The central angle of the deflection plane The initial length of the fishing line (112) in the finger body (11) is set to The microcontroller (42) drives the servo motor (13), which in turn drives the servo disc (14) to rotate. After the finger bends and deflects, the change in the length of the fishing line is... ,in Indicates the first The current length of the fishing line (112) in the finger body (11) is: The cross-sectional radius of the core of the finger body (11) is R. Based on the motion process, kinematic analysis of the flexible finger can be performed to obtain the pose parameters of the finger body (11). The change in the fishing line (112) The relationship between them; Performing forward kinematic analysis on the fingers, the current length of the fishing line (112) is... ; ， Length of the central arc of the finger body (11) Change in the central arc It can be made from 4 fishing lines (112) of different lengths. With change Seek; ， From this, the pose parameters of the finger body (11) can be derived. The current length of the fishing line (112) in the finger body (11) The relationship between them is: ， The pose parameters of the finger body (11) can be obtained from formulas (1), (2), and (3). The change in the fishing line (112) Relationship between them: ， Change in fishing line (112) Rotation angle of rudder (14) The relationship between them is shown in formula (7): ， in The radius of the rudder (14) The range of values ​​is Substituting formula (7) into formulas (4), (5), and (6) yields the mapping relationship between the rotation angle of the rudder (14) and the three pose parameters of the finger body (11): ， In formula (10) The position of the flexible finger after motion transformation can be obtained from the rotation angle of the rudder (14), thus completing the forward kinematic analysis of the flexible finger. Inverse kinematics analysis of the flexible finger decomposes its motion into two parts: the flexible finger first rotates... Shaft bending angle Then rotate around the z-axis by an angle This allows us to obtain the flexible finger base point. To the end point of the flexible finger after transformation Homogeneous transformation matrix T ， The end point of flexible finger after bending and deflection The coordinate system at that location is Let be the pose matrix of the endpoint. Representing the coordinate system of the endpoints respectively The direction vector of the axis in the base coordinate system. ， ， Substituting formulas (13), (14), and (15) into formulas (1), (3), and (7), the rotation angle of each rudder disk (14) can be obtained based on the pose of the end point. Thus, the rotation angle of the corresponding rudder disk (14) can be obtained based on the end pose of the flexible finger, thereby completing the inverse kinematic analysis of the flexible finger.

2. A grasping method for a rope-driven pleated flexible gripper with end-adhesion function, wherein the flexible gripper drives a servo motor (13) to rotate according to the kinematic modeling and analysis method according to claim 1, characterized in that: The flexible gripper has three grasping modes to grasp objects of different sizes and shapes; Grasping mode 1: When the size of the object to be grasped is moderate and can be enveloped by the flexible gripper, the microcontroller (42) drives the servo motor (13) to rotate, which drives the servo disk (14) to rotate and thus change the relative length of the fishing line (112). The fishing line (112) acts as a tendon to drive the three flexible fingers to bend and envelop the object to be grasped, thus completing the grasping task. Grasping mode 2: When the size of the object is too large and exceeds the line length limit of the flexible claw, the grasping task cannot be completed by relying on the bending and enveloping of the fingers. At this time, the microcontroller (42) drives the air pump (41) and uses the adsorption device at the end of the flexible claw to complete the grasping task of the larger object. Grasping Mode 3: When facing a narrow or deep working environment, the entire flexible gripper cannot fully enter the working environment, and the bending and grasping of the fingers are restricted. At this time, single-finger drive is performed. After a single finger enters the working environment, the microcontroller (42) drives the air pump (41) to complete the grasping task by using the adsorption function of the finger end adsorption device.

3. The grasping method according to claim 2, characterized in that, The second grasping mode also includes when the object is too small, making it difficult for the fingers to apply enough contact area and force, the microcontroller (42) drives the air pump (41) to complete the grasping task of the small object by using the suction device of the flexible claw.

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