A parallel link driven mechanical finger with four degrees of freedom

Abstract

The application relates to the technical field of robots, and provides a parallel connecting rod driving mechanical finger with four degrees of freedom, which comprises a base and first, second, third and fourth driving mechanisms which are arranged in parallel on the base; the mechanical finger further comprises MCP joints, PIP joints and DIP joints which are connected in sequence, and the MCP joints are connected with the base through universal joints; the first and second driving mechanisms are connected with two sides of the MCP joints respectively to drive the MCP joints to perform pitching and yawing movements; the third driving mechanism is connected with the PIP joints to drive the PIP joints to perform pitching movements; and the fourth driving mechanism is connected with the DIP joints to drive the DIP joints to perform pitching movements. The four degrees of freedom of the application have high dexterity and good repeatability positioning accuracy; high load-carrying ratio, high rigidity and high energy density are realized; the branch chain structure has good interchangeability, the overall structure is simple and compact, and the space occupation ratio is small.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of robot technology, more particularly, to a parallel link driving mechanical finger with four degrees of freedom. BACKGROUND

[0002] The mechanical finger is an important component of forming a robot and operating the robot, and directly determines the functional task and the performance quality of the operation. The mechanical finger in the prior art mainly adopts the structure of tendon mechanism (tendon rope, rope transmission) and the structure of link mechanism (including four-bar mechanism, gear, belt transmission, etc.), and both of them have the technical problems of insufficient dexterity and poor repeatability positioning accuracy. SUMMARY

[0003] The purpose of the present application is to provide a parallel link driving mechanical finger with four degrees of freedom, so as to solve the technical problems of insufficient dexterity and poor repeatability positioning accuracy of the mechanical finger in the prior art.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is:

[0005] The present application provides a parallel link driving mechanical finger with four degrees of freedom, comprising a base and a first driving mechanism, a second driving mechanism, a third driving mechanism and a fourth driving mechanism which are parallelly arranged on the base;

[0006] The mechanical finger further comprises an MCP joint, a PIP joint and a DIP joint which are connected in sequence, and the MCP joint is connected with the base through a universal joint;

[0007] The first driving mechanism and the second driving mechanism are respectively connected to both sides of the MCP joint, so as to drive the MCP joint to perform pitching motion and yawing motion;

[0008] The third driving mechanism is connected to the PIP joint, so as to drive the PIP joint to perform pitching motion;

[0009] The fourth driving mechanism is connected to the DIP joint, so as to drive the DIP joint to perform pitching motion.

[0010] According to the parallel link driving mechanical finger with four degrees of freedom described above, the MCP joint comprises a first MCP link and a second MCP link, the universal joint is arranged between the first MCP link and the second MCP link and located at one end of the first MCP link and the second MCP link close to the base, and the universal joint is connected with the first MCP link, the second MCP link and the base;

[0011] The first driving mechanism is connected with the first MCP link, and the second driving mechanism is connected with the second MCP link.

[0012] According to the parallel link driven mechanical finger with four degrees of freedom, the first driving mechanism comprises:

[0013] A first joint bearing seat is arranged on the base and connected with the base;

[0014] A first linear motor is arranged on the first joint bearing seat and connected with the first joint bearing seat;

[0015] A first joint bearing is arranged on the first linear motor and connected with the first linear motor, and the first joint bearing is connected with the first MCP link.

[0016] According to the parallel link driven mechanical finger with four degrees of freedom, the second driving mechanism comprises:

[0017] A second joint bearing seat is arranged on the base and connected with the base;

[0018] A second linear motor is arranged on the second joint bearing seat and connected with the second joint bearing seat;

[0019] A second joint bearing is arranged on the second linear motor and connected with the second linear motor, and the second joint bearing is connected with the second MCP link.

[0020] According to the parallel link driven mechanical finger with four degrees of freedom, the PIP joint comprises a first PIP link, a second PIP link, a first linkage rod and a first rotating shaft;

[0021] The MCP joint is connected with the first PIP link and the second PIP link through the first rotating shaft, the first linkage rod is arranged between the first PIP link and the second PIP link, one end of the first linkage rod is connected with the first rotating shaft, and the other end is connected with the third driving mechanism.

[0022] According to the parallel link driven mechanical finger with four degrees of freedom, the third driving mechanism comprises:

[0023] A third joint bearing seat is arranged on the base and connected with the base;

[0024] A third linear motor is arranged on the third joint bearing seat and connected with the third joint bearing seat;

[0025] A third joint bearing is arranged on and connected with the third linear motor;

[0026] A first linkage shaft is arranged on and connected with the third joint bearing;

[0027] A fourth joint bearing is arranged on and connected with the first linkage shaft, and the fourth joint bearing is connected with the first linkage rod.

[0028] According to the parallel linkage driving mechanical finger with four degrees of freedom as described above, the DIP joint comprises a DIP linkage rod, a second linkage rod, a second rotating shaft and a third rotating shaft, and the second rotating shaft and the third rotating shaft are arranged on the DIP linkage rod;

[0029] The first PIP linkage rod and the second PIP linkage rod are connected with the DIP linkage rod through the second rotating shaft, one end of the second linkage rod is connected with the third rotating shaft, and the other end is connected with the fourth driving mechanism.

[0030] According to the parallel linkage driving mechanical finger with four degrees of freedom as described above, the DIP joint further comprises a fourth rotating shaft, a third linkage rod and a fourth linkage rod;

[0031] One end of the third linkage rod is rotationally connected with the first rotating shaft, and the other end is arranged on the second linkage rod and connected with the second linkage rod through the fourth rotating shaft;

[0032] One end of the fourth linkage rod is rotationally connected with the first rotating shaft, and the other end is arranged on the second linkage rod and connected with the second linkage rod through the fourth rotating shaft;

[0033] The first rotating shaft, the fourth rotating shaft, the second rotating shaft, the third rotating shaft, the third linkage rod, the second linkage rod, the DIP linkage rod and the first PIP linkage rod constitute an inverse quadrilateral linkage mechanism;

[0034] The first rotating shaft, the fourth rotating shaft, the second rotating shaft, the third rotating shaft, the fourth linkage rod, the second linkage rod, the DIP linkage rod and the second PIP linkage rod constitute an inverse quadrilateral linkage mechanism.

[0035] According to the parallel linkage driving mechanical finger with four degrees of freedom as described above, the fourth driving mechanism comprises:

[0036] A fourth joint bearing seat is arranged on and connected with the base;

[0037] A fourth linear motor is arranged on and connected with the fourth joint bearing seat;

[0038] A fifth joint bearing is arranged on and connected with the fourth linear motor;

[0039] A second linkage shaft is arranged on and connected with the fifth joint bearing;

[0040] A sixth joint bearing is arranged on and connected with the second linkage shaft, and the sixth joint bearing is connected with the second linkage rod.

[0041] According to the parallel linkage driving mechanical finger with four degrees of freedom, the MCP joint has a pitching motion range of 0°-90°.

[0042] The MCP joint has a yawing motion range of -35°-35°.

[0043] The PIP joint has a pitching motion range of 0°-90°.

[0044] The DIP joint has a pitching motion range of 0°-90°.

[0045] The parallel linkage driving mechanical finger with four degrees of freedom has at least the following beneficial effects:

[0046] The parallel linkage driving mechanical finger with four degrees of freedom realizes the pitching motion and yawing motion of the MCP joint through the cooperation of the first driving mechanism, the second driving mechanism and the universal joint, realizes the pitching motion of the PIP joint through the third driving mechanism, realizes the pitching motion of the DIP joint through the fourth driving mechanism, and thus realizes four degrees of freedom, and the four degrees of freedom have high dexterity, the use effect is similar to or even surpasses that of a human finger, can accurately and precisely imitate the human finger to perform motion or grasping operation, has good repeat positioning accuracy; the four driving mechanisms in parallel can simultaneously bear the end load, the end load can reach 280N, realizes high load ratio, high stiffness and high energy density, and the branch chain structure has good interchangeability, the overall structure is simple and compact, has small space proportion, and is convenient for compact collection of five fingers of a mechanical hand. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0048] Figure 1 Side view of the mechanical finger of the present invention Figure 1 ;

[0049] Figure 2 Pronation of the MCP joint of the mechanical finger of the present invention

[0050] Figure 3 Supination of the MCP joint of the mechanical finger of the present invention

[0051] Figure 4 Pronation of the PIP joint of the mechanical finger of the present invention

[0052] Figure 5 Supination of the DIP joint of the mechanical finger of the present invention

[0053] Figure 6 Rear view of the mechanical finger of the present invention

[0054] Figure 7 Side view of the mechanical finger of the present invention Figure 2 ;

[0055] Figure 8 Side view of the mechanical finger of the present invention Figure 3 ;

[0056] Figure 9 Top view of the mechanical finger of the present invention

[0057] Figure 10 Top view of the mechanical finger of the present invention

[0058] Figure 11 Rear view of the mechanical finger of the present invention

[0059] Figure 12 Side view of the mechanical finger of the present invention Figure 4 .

[0060] Wherein, the reference signs in the figures:

[0061] 100, mechanical finger; 10, base; 20, first driving mechanism; 21, first joint bearing seat; 22, first linear motor; 23, first joint bearing; 30, second driving mechanism; 31, first joint bearing seat; 32, second linear motor; 33, first joint bearing; 40, third driving mechanism; 41, third joint bearing seat; 42, third linear motor; 43, third joint bearing; 44, first linkage shaft; 45, fourth joint bearing; 50, fourth driving mechanism; 51, fourth joint bearing seat; 52, fourth linear motor; 53, fifth joint bearing; 54, second linkage shaft; 55, sixth joint bearing; 60, MCP joint; 61, first MCP connecting rod; 62, second MCP connecting rod; 70, PIP joint; 71, first PIP connecting rod; 72, second PIP connecting rod; 73, first linkage rod; 74, first rotating shaft; 80, DIP joint; 81, DIP connecting rod; 82, second linkage rod; 83, second rotating shaft; 84, third rotating shaft; 85, fourth rotating shaft; 86, third linkage rod; 87, fourth linkage rod; 90, universal joint. DETAILED DESCRIPTION

[0062] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects more clearly understood, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0063] It should be noted that when a component is referred to as "fixed to" or "disposed on" another component, it can be directly or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly or indirectly connected to the other component. The terms "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or position based on the orientation or position shown in the drawings, and are only for the convenience of description, and cannot be understood as a limitation on the technical solutions. The terms "first", "second" are only for the purpose of convenient description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0064] The main technical terms involved in the present application are explained as follows:

[0065] MCP joint (English full name: Metacarpo-phalangeal joints, Chinese full name: metacarpal phalangeal joint);

[0066] PIP joint (Proximal interphalangeal joints, one of the joints of human fingers);

[0067] DIP joint (Distal interphalangeal joints, one of the joints of human fingers);

[0068] Universal joint (universal joint, also known as U pair, referred to as U, with two degrees of freedom);

[0069] Joint bearing, spherical joint bearing (spherical joint, referred to as S, with three degrees of freedom);

[0070] Linear motor (prismatic joint, also known as moving pair, referred to as P, with one degree of freedom);

[0071] Rotary shaft (rotational joint, also known as rotating pair, referred to as R, with one degree of freedom);

[0072] Cylindrical pair (cylindrical joint, also known as cylindrical pair, referred to as C, two degrees of freedom pair).

[0073] The present application relates to the naming of some connecting rods, which are represented by the above-mentioned letter combinations, which represent the meaning of the motion pair represented by the letter connected in turn according to the front and back order to constitute a connecting rod mechanism.

[0074] For example: SPS connecting rod mechanism (spherical joint-prismatic joint-spherical joint, a series of connecting rod mechanisms composed of joint bearing-moving pair-joint bearing);

[0075] PSSR connecting rod mechanism (prismatic joint-spherical joint-spherical joint-rotational joint, a series of connecting rod mechanisms composed of moving pair-joint bearing-joint bearing-rotating pair).

[0076] And so on.

[0077] Please refer to Figure 1The embodiment provides a parallel link driving mechanical finger 100 with four degrees of freedom, which comprises a base 10, a first driving mechanism 20, a second driving mechanism 30, a third driving mechanism 40 and a fourth driving mechanism 50 which are arranged in parallel on the base 10. The mechanical finger 100 further comprises an MCP joint 60, a PIP joint 70 and a DIP joint 80 which are connected in sequence, and the MCP joint 60 is connected with the base 10 through a universal joint 90. The first driving mechanism 20 and the second driving mechanism 30 are connected with two sides of the MCP joint 60 respectively, so as to drive the MCP joint 60 to perform pitching motion and yawing motion; the third driving mechanism 40 is connected with the PIP joint 70, so as to drive the PIP joint 70 to perform pitching motion; and the fourth driving mechanism 50 is connected with the DIP joint 80, so as to drive the DIP joint 80 to perform pitching motion.

[0078] The working principle of the parallel link driving mechanical finger 100 with four degrees of freedom provided by the embodiment is as follows:

[0079] Please refer to Figure 2 , Figure 2 (a), Figure 2 (b), Figure 2 (c) respectively represent the pitching motion process of the MCP joint 60, when the third driving mechanism 40 and the fourth driving mechanism 50 are not driven, the first driving mechanism 20 and the second driving mechanism 30 are driven, and through the cooperation of the universal joint 90, the first driving mechanism 20 and the second driving mechanism 30 are driven to move up and down in the same direction and at the same length, so that the single freedom pitching motion of the MCP joint 60 of the mechanical finger 100 is realized.

[0080] Please refer to Figure 3 , Figure 3 (a), Figure 3 (b), Figure 3 (c) respectively represent the yawing motion process of the MCP joint 60, when the third driving mechanism 40 and the fourth driving mechanism 50 are not driven, the first driving mechanism 20 and the second driving mechanism 30 are driven, and through the cooperation of the universal joint 90, the first driving mechanism 20 and the second driving mechanism 30 are driven to move up and down in opposite directions and at the same length, so that the single freedom yawing motion of the MCP joint 60 of the mechanical finger 100 is realized.

[0081] Please refer to Figure 2 and Figure 3When the third driving mechanism 40 and the fourth driving mechanism 50 are not moved, the first driving mechanism 20 and the second driving mechanism 30 are driven to move in the same direction and different lengths, and through the cooperation of the universal joint 90, the two degrees of freedom of the pitch and roll of the MCP joint 60 of the mechanical finger 100 can be simultaneously driven.

[0082] Referring to Figure 4 , Figure 4 (a), Figure 4 (b), Figure 4 (c) respectively represent the pitch movement process of the PIP joint 70, when the first driving mechanism 20, the second driving mechanism 30 and the fourth driving mechanism 50 are not moved, the third driving mechanism 40 is driven to move up and down, and the single degree of freedom of the pitch movement of the PIP joint 70 of the mechanical finger 100 is realized.

[0083] Referring to Figure 5 , Figure 5 (a), Figure 5 (b), Figure 5 (c) respectively represent the pitch movement process of the DIP joint 80, when the first driving mechanism 20, the second driving mechanism 30 and the third driving mechanism 40 are not moved, the fourth driving mechanism 50 is driven to move, and the single degree of freedom of the pitch movement of the DIP joint 80 of the mechanical finger 100 is realized.

[0084] It can be seen that the pitch movement and the roll movement of the MCP joint 60 are realized through the cooperation of the first driving mechanism 20, the second driving mechanism 30 and the universal joint 90, the pitch movement of the PIP joint 70 is realized through the third driving mechanism 40, and the pitch movement of the DIP joint 80 is realized through the fourth driving mechanism 50, so that the mechanical finger 100 realizes four degrees of freedom.

[0085] The parallel linkage driven mechanical finger 100 with four degrees of freedom provided by the embodiment has the beneficial effects that: the pitch movement and the roll movement of the MCP joint 60 are realized through the cooperation of the first driving mechanism 20, the second driving mechanism 30 and the universal joint 90, the pitch movement of the PIP joint 70 is realized through the third driving mechanism 40, and the pitch movement of the DIP joint 80 is realized through the fourth driving mechanism 50, so that the mechanical finger 100 realizes four degrees of freedom, and the four degrees of freedom have high dexterity, the use effect is similar to or even surpasses that of a human finger, can accurately and accurately imitate the human finger to move or grasp and the like, and has good repeated positioning accuracy; the four driving mechanisms are connected in parallel to simultaneously bear the end load, the end load can reach 280N in theory, high load ratio, high stiffness and high energy density are realized, the branch chain structure has good interchangeability, the overall structure is simple and compact, the space occupation ratio is small, and the compact collection of the five fingers of the mechanical hand is facilitated.

[0086] In one embodiment, please refer to Figure 1 and Figure 6 , the MCP joint 60 includes a first MCP connecting rod 61 and a second MCP connecting rod 62, the universal joint 90 is arranged between the first MCP connecting rod 61 and the second MCP connecting rod 62 and located at one end of the first MCP connecting rod 61 and the second MCP connecting rod 62 close to the base 10, the universal joint 90 is connected with the first MCP connecting rod 61, the second MCP connecting rod 62, and the base 10, the first driving mechanism 20 is connected with the first MCP connecting rod 61, and the second driving mechanism 30 is connected with the second MCP connecting rod 62.

[0087] The universal joint 90 with two degrees of freedom of pitch and roll is installed on the base 10, and the universal joint 90 is used to connect the end of the first MCP connecting rod 61 and the end of the second MCP connecting rod 62, the first driving mechanism 20 is connected to the first MCP connecting rod 61, and the second driving mechanism 30 is connected to the second MCP connecting rod 62, and the pitch movement and the roll movement of the first MCP connecting rod 61 and the second MCP connecting rod 62 are realized through the joint action of the first driving mechanism 20, the second driving mechanism 30 and the universal joint 90.

[0088] In one embodiment, the first driving mechanism 20 and the second driving mechanism 30 are the same in structure and are symmetrically arranged, which facilitates the realization of the pitch movement and the roll movement of the MCP joint 60.

[0089] In one embodiment, please refer to Figure 7 , the first driving mechanism 20 includes a first joint bearing seat 21, a first linear motor 22 and a first joint bearing 23. The first joint bearing seat 21 is arranged on the base 10 and connected with the base 10; the first linear motor 22 is arranged on the first joint bearing seat 21 and connected with the first joint bearing seat 21; the first joint bearing 23 is arranged on the first linear motor 22 and connected with the first linear motor 22, and the first joint bearing 23 is connected with the first MCP connecting rod 61.

[0090] The first linear motor 22 adopted by the first driving mechanism 20 is a direct drive type, which has only one direction of freedom, and the first joint bearing seat 21 and the first joint bearing 23 both have three degrees of freedom, so that the first driving mechanism 20 is more flexible and agile when driving the first MCP connecting rod 61 to perform the pitch movement and the roll movement. The first joint bearing seat 21 (S), the first linear motor 22 (P), the first joint bearing 23 (S) and the first MCP connecting rod 61 constitute an SPS connecting rod mechanism.

[0091] In one embodiment, please refer to Figure 8The second driving mechanism 30 comprises a first joint bearing seat 31, a second linear motor 32 and a first joint bearing 33. The first joint bearing seat 31 is arranged on and connected with the base 10. The second linear motor 32 is arranged on and connected with the first joint bearing seat 31. The first joint bearing 33 is arranged on and connected with the second linear motor 32, and the first joint bearing 33 is connected with the second MCP connecting rod 62.

[0092] The second linear motor 32 of the second driving mechanism 30 is in a direct drive mode, and has only one degree of freedom. The first joint bearing seat 31 and the first joint bearing 33 each have three degrees of freedom, so that the second driving mechanism 30 is more flexible and agile when driving the second MCP connecting rod 62 to perform the pitching motion and the yawing motion. The first joint bearing seat 31 (S), the second linear motor 32 (P), the first joint bearing 33 (S) and the second MCP connecting rod 62 constitute an SPS connecting rod mechanism. Two SPS connecting mechanisms and a universal joint 90 constitute a 2SPS&U parallel mechanism.

[0093] In an embodiment, referring to Figure 9 and Figure 10 The PIP joint 70 comprises a first PIP connecting rod 71, a second PIP connecting rod 72, a first linkage rod 73 and a first rotary shaft 74. The MCP joint 60 is connected with the first PIP connecting rod 71 and the second PIP connecting rod 72 through the first rotary shaft 74. The first linkage rod 73 is arranged between the first PIP connecting rod 71 and the second PIP connecting rod 72, and one end of the first linkage rod 73 is connected with the first rotary shaft 74, and the other end is connected with the third driving mechanism 40.

[0094] One end of the first PIP connecting rod 71 and one end of the second PIP connecting rod 72 are each connected on the first rotary shaft 74 having one degree of freedom of rotation, and one end of the first linkage rod 73 is also connected on the first rotary shaft 74, and the other end is connected with the third driving mechanism 40, so as to realize driving the first PIP connecting rod 71 and the second PIP connecting rod 72 to perform the pitching motion by the third driving mechanism 40.

[0095] In an embodiment, the first MCP connecting rod 61, the second MCP connecting rod 62, the first PIP connecting rod 71, the second PIP connecting rod 72 and the first linkage rod 73 are each connected on the first rotary shaft 74.

[0096] In an embodiment, referring to Figure 11The third driving mechanism 40 comprises a third joint bearing seat 41, a third linear motor 42, a third joint bearing 43, a first linkage shaft 44, and a fourth joint bearing 45. The third joint bearing seat 41 is arranged on and connected with the base 10. The third linear motor 42 is arranged on and connected with the third joint bearing seat 41. The third joint bearing 43 is arranged on and connected with the third linear motor 42. The first linkage shaft 44 is arranged on and connected with the third joint bearing 43. The fourth joint bearing 45 is arranged on and connected with the first linkage shaft 44, and is connected with the PIP joint 70, that is, the fourth joint bearing 45 is connected with the first linkage rod 73.

[0097] The third linear motor 42 of the third driving mechanism 40 is in a direct drive mode, and has only one direction of freedom. The third joint bearing seat 41, the third joint bearing 43, and the fourth joint bearing 45 each have three degrees of freedom, so that the third driving mechanism 40 is more flexible and agile when driving the first PIP linkage rod 71 and the second PIP linkage rod 72 to perform the pitching motion. The third linear motor 42 (P), the third joint bearing 43 (S), the fourth joint bearing 45 (S), the first rotary shaft 74 (R), and the first PIP linkage rod 71 and the second PIP linkage rod 72 constitute a PSSR linkage mechanism.

[0098] In an embodiment, referring to Figure 9 and Figure 10 The DIP joint 80 comprises a DIP linkage rod 81, a second linkage rod 82, a second rotary shaft 83, and a third rotary shaft 84. The second rotary shaft 83 and the third rotary shaft 84 are each arranged on the DIP linkage rod 81. The first PIP linkage rod 71 and the second PIP linkage rod 72 are connected with the DIP linkage rod 81 through the second rotary shaft 83. One end of the second linkage rod 82 is connected with the third rotary shaft 84, and the other end is connected with the fourth driving mechanism 50. The PIP joint 70 and the DIP linkage rod 81 are each connected on the second rotary shaft 83 having one direction of freedom of rotation. One end of the second linkage rod 82 is connected on the third rotary shaft 84, and the other end is connected on the fourth driving mechanism 50, so as to realize driving the DIP linkage rod 81 to perform the pitching motion through the fourth driving mechanism 50. Optionally, the DIP linkage rod 81 is provided with an anti-skid part at the finger part, which plays an anti-skid effect when grabbing the object.

[0099] In an embodiment, the first PIP linkage rod 71, the second PIP linkage rod 72, and the DIP linkage rod 81 are each connected on the second rotary shaft 83.

[0100] In one embodiment, please refer to Figure 9 and Figure 10 , the DIP joint 80 further comprises a fourth rotating shaft 85, a third linkage rod 86 and a fourth linkage rod 87. One end of the third linkage rod 86 is rotatably connected with the first rotating shaft 74, and the other end is arranged on the second linkage rod 82 and connected with the second linkage rod 82 through the fourth rotating shaft 85; one end of the fourth linkage rod 87 is rotatably connected with the first rotating shaft 74, and the other end is arranged on the second linkage rod 82 and connected with the second linkage rod 82 through the fourth rotating shaft 85. The first rotating shaft 74, the fourth rotating shaft 85, the second rotating shaft 83, the third rotating shaft 84, the third linkage rod 86, the second linkage rod 82, the DIP linkage rod 81 and the first PIP linkage rod 71 constitute a reverse quadrilateral linkage mechanism (part A in Figure 10 ); the first rotating shaft 74, the fourth rotating shaft 85, the second rotating shaft 83, the third rotating shaft 84, the fourth linkage rod 87, the second linkage rod 82, the DIP linkage rod 81 and the second PIP linkage rod 72 constitute a reverse quadrilateral linkage mechanism.

[0101] The reverse quadrilateral is arranged so that the fourth driving mechanism 50 can more effectively control the pitch degree of freedom when driving the DIP joint 80.

[0102] In one embodiment, the first MCP linkage rod 61, the second MCP linkage rod 62, the first PIP linkage rod 71, the second PIP linkage rod 72, the first linkage rod 73, the third linkage rod 86 and the fourth linkage rod 87 are all connected to the first rotating shaft 74.

[0103] In one embodiment, please refer to Figure 12 , the fourth driving mechanism 50 comprises a fourth joint bearing seat 51, a fourth linear motor 52, a fifth joint bearing 53, a second linkage shaft 54 and a sixth joint bearing 55.

[0104] The fourth joint bearing seat 51 is arranged on and connected with the base 10;

[0105] The fourth linear motor 52 is arranged on and connected with the fourth joint bearing seat 51;

[0106] The fifth joint bearing 53 is arranged on and connected with the fourth linear motor 52;

[0107] The second linkage shaft 54 is arranged on and connected with the fifth joint bearing 53;

[0108] The sixth joint bearing 55 is arranged on and connected with the second linkage shaft 54, and the sixth joint bearing 55 is connected with the DIP joint 80, that is, the sixth joint bearing 55 is connected with the second linkage rod 82.

[0109] The fourth linear motor 52 adopted by the fourth driving mechanism 50 is in a direct drive mode, and has only one direction of freedom, and the fourth joint bearing seat 51, the fifth joint bearing 53 and the sixth joint bearing 55 all have three degrees of freedom, so that the fourth driving mechanism 50 is more flexible and agile when driving the DIP linkage rod 81 to perform the pitching motion. The fourth linear motor 52 (P), the fifth joint bearing 53 (S), the sixth joint bearing 55 (S), the fourth rotating shaft 85 (R) and the DIP linkage rod 81 constitute a PSSR linkage mechanism, which is coupled with a reverse quadrilateral linkage mechanism to form a PSSR-reverse quadrilateral parallel mechanism.

[0110] In an embodiment, referring to Figure 2 , the MCP joint 60 has a pitching motion range of 0°-90°, and the pitching angle of the MCP joint of a human finger is up to 90°. Referring to Figure 3 , the MCP joint 60 has a side swing motion range of -35°-35°, and the swing range of the MCP joint of a human finger is -30°-30°. Referring to Figure 4 , the PIP joint 70 has a pitching motion range of 0°-90°, and the pitching angle of the PIP joint of a human finger is up to 90°. Referring to Figure 5 , the DIP joint 80 has a pitching motion range of 0°-90°, and the pitching angle of the DIP joint of a human finger is up to 90°. The motion ranges of the MCP joint, the PIP joint and the DIP joint in the embodiment are similar to those of a human finger, and have high dexterity.

[0111] In summary, the complete mechanism of the parallel linkage driving mechanical finger with four degrees of freedom provided in the embodiment of the application is a 2SPS&U&2PSSR-reverse quadrilateral hybrid mechanism, and a plurality of component sub-mechanisms can be equivalently replaced as follows, which are all within the protection of the patent.

[0112] (1) The 2SPS&U component sub-mechanism can be replaced by:

[0113] a 2UPS&U parallel mechanism;

[0114] a 2RSS&U parallel mechanism;

[0115] a 2RUS&U parallel mechanism;

[0116] a 2PUS&U parallel mechanism;

[0117] a 2RCS&U parallel mechanism;

[0118] SPS & PUS & U parallel mechanism;

[0119] SPS & RCS & U parallel mechanism;

[0120] SPS & RSS & U parallel mechanism;

[0121] PUS & SPS & U parallel mechanism;

[0122] PUS & RCS & U parallel mechanism;

[0123] PUS & RSS & U parallel mechanism;

[0124] RCS & SPS & U parallel mechanism;

[0125] RCS & PUS & U parallel mechanism;

[0126] RCS & RSS & U parallel mechanism;

[0127] etc.

[0128] (2) for 2PSSR assembly sub-mechanism to replace:

[0129] 2SPSR, 2UPSR, 2PUSR, 2SPUR, 2PSSP;

[0130] PSSR & SPSR parallel mechanism;

[0131] PSSR & UPSR parallel mechanism;

[0132] PSSR & RSSP parallel mechanism;

[0133] PSSR & PSSP parallel mechanism;

[0134] PSSR & RSSR parallel mechanism;

[0135] PSSR & SPUR parallel mechanism;

[0136] UPSR & SPSR parallel mechanism;

[0137] UPSR & RSSP parallel mechanism;

[0138] UPSR & PSSP parallel mechanism;

[0139] RSSP & PSSP parallel mechanism;

[0140] RSSP & SPSR parallel mechanism;

[0141] PSSP & RSSR parallel mechanism;

[0142] RSSR & SPUR parallel mechanism;

[0143] SPUR & SPSR parallel mechanism;

[0144] etc.

[0145] (3) The anti-tetragon assembly sub-mechanism can be replaced by:

[0146] a regular tetragon, any other single degree of freedom mechanism (including a six-bar mechanism, an eight-bar mechanism, etc.).

[0147] In summary, the mechanical finger 100 with four degrees of freedom provided by the embodiment includes a base 10 and a first driving mechanism 20, a second driving mechanism 30, a third driving mechanism 40, and a fourth driving mechanism 50 which are in parallel on the base 10. The mechanical finger 100 further includes an MCP joint 60, a PIP joint 70, and a DIP joint 80 which are connected in sequence, and the MCP joint 60 is connected with the base 10 through a universal joint 90. The first driving mechanism 20 and the second driving mechanism 30 are respectively connected to two sides of the MCP joint 60 to drive the MCP joint 60 to perform pitching and yawing movements; the third driving mechanism 40 is connected to the PIP joint 70 to drive the PIP joint 70 to perform pitching movement; and the fourth driving mechanism 50 is connected to the DIP joint 80 to drive the DIP joint 80 to perform pitching movement. The pitching and yawing movements of the MCP joint 60 are realized through the cooperation of the first driving mechanism 20, the second driving mechanism 30, and the universal joint 90, the pitching movement of the PIP joint 70 is realized through the third driving mechanism 40, and the pitching movement of the DIP joint 80 is realized through the fourth driving mechanism 50, so that the mechanical finger 100 realizes four degrees of freedom, and the four degrees of freedom have high dexterity, the use effect is similar to or even surpasses that of a human finger, the mechanical finger can accurately and precisely imitate a human finger to perform operations such as movement or grabbing, and has good repeat positioning accuracy; the four driving mechanisms in parallel can simultaneously bear an end load, the theoretical end load can reach 280N, high load ratio, high stiffness, and high energy density are realized, the branch chain structure has good interchangeability, the overall structure is simple and compact, the space occupancy ratio is small, and the compact collection of five fingers of a mechanical hand is facilitated.

[0148] The above only describes preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A parallel linkage driven mechanical finger with four degrees of freedom, characterized in that, It includes a base and a first drive mechanism, a second drive mechanism, a third drive mechanism and a fourth drive mechanism connected in parallel on the base; The mechanical finger also includes an MCP joint, a PIP joint, and a DIP joint connected in sequence, and the MCP joint is connected to the base via a universal joint. The first drive mechanism and the second drive mechanism are respectively connected to both sides of the MCP joint to drive the MCP joint to perform pitch and lateral movements. The third drive mechanism is connected to the PIP joint to drive the PIP joint to perform pitching motion; The fourth drive mechanism is connected to the DIP joint to drive the DIP joint to perform pitching motion; The MCP joint includes a first MCP link and a second MCP link. The universal joint is located between the first MCP link and the second MCP link and at one end of the first MCP link and the second MCP link near the base. The universal joint is connected to the first MCP link, the second MCP link, and the base. The first drive mechanism is connected to the first MCP link, and the second drive mechanism is connected to the second MCP link. The first driving mechanism includes: A first joint bearing housing is disposed on the base and connected to the base; A first linear motor is mounted on and connected to the first joint bearing housing. The first joint bearing is mounted on and connected to the first linear motor, and the first joint bearing is connected to the first MCP connecting rod. Both the first joint bearing housing and the first joint bearing have three degrees of freedom; The second drive mechanism includes: The second joint bearing housing is disposed on the base and connected to the base; A second linear motor is mounted on and connected to the second joint bearing housing. The second joint bearing is mounted on and connected to the second linear motor, and the second joint bearing is connected to the second MCP connecting rod. Both the second joint bearing housing and the second joint bearing have three degrees of freedom.

2. The parallel linkage driven mechanical finger with four degrees of freedom according to claim 1, characterized in that, The PIP joint includes a first PIP link, a second PIP link, a first linkage rod, and a first rotation axis; The MCP joint is connected to the first PIP link and the second PIP link via the first rotating shaft. The first linkage rod is located between the first PIP link and the second PIP link, with one end of the first linkage rod connected to the first rotating shaft and the other end connected to the third drive mechanism.

3. The parallel linkage driven mechanical finger with four degrees of freedom according to claim 2, characterized in that, The third drive mechanism includes: The third joint bearing housing is disposed on the base and connected to the base; A third linear motor is mounted on the third joint bearing housing and connected to the third joint bearing housing; The third joint bearing is mounted on and connected to the third linear motor. A first linkage shaft is mounted on and connected to the third joint bearing. A fourth joint bearing is provided on and connected to the first linkage shaft, and the fourth joint bearing is connected to the first linkage rod.

4. The parallel linkage driven mechanical finger with four degrees of freedom according to claim 2, characterized in that, The DIP joint includes a DIP link, a second linkage, a second rotation axis, and a third rotation axis, wherein the second rotation axis and the third rotation axis are both disposed on the DIP link; The first PIP link and the second PIP link are connected to the DIP link via a second rotating shaft. One end of the second linkage is connected to the third rotating shaft, and the other end is connected to the fourth drive mechanism.

5. The parallel linkage driven mechanical finger with four degrees of freedom according to claim 4, characterized in that, The DIP joint also includes a fourth rotation axis, a third linkage, and a fourth linkage. One end of the third linkage is rotatably connected to the first rotating shaft, and the other end is disposed on the second linkage and connected to the second linkage through the fourth rotating shaft; One end of the fourth linkage is rotatably connected to the first rotating shaft, and the other end is disposed on the second linkage and connected to the second linkage through the fourth rotating shaft; The first rotating shaft, the fourth rotating shaft, the second rotating shaft, the third rotating shaft, the third linkage rod, the second linkage rod, the DIP link, and the first PIP link constitute an inverted quadrilateral linkage mechanism. The first rotating shaft, the fourth rotating shaft, the second rotating shaft, the third rotating shaft, the fourth linkage rod, the second linkage rod, the DIP link, and the second PIP link constitute an inverted quadrilateral linkage mechanism.

6. The parallel linkage driven mechanical finger with four degrees of freedom according to claim 5, characterized in that, The fourth drive mechanism includes: A fourth joint bearing housing, wherein the fourth joint bearing housing is disposed on the base and connected to the base; A fourth linear motor, wherein the fourth linear motor is mounted on the fourth joint bearing housing and connected to the fourth joint bearing housing; The fifth joint bearing is mounted on and connected to the fourth linear motor. The second linkage shaft is mounted on the fifth joint bearing and connected to the fifth joint bearing; A sixth joint bearing is provided on and connected to the second linkage shaft, and the sixth joint bearing is connected to the second linkage rod.

7. The parallel linkage driven mechanical finger with four degrees of freedom according to claim 1, characterized in that, The pitch range of the MCP joint is 0°~90°; The lateral swing range of the MCP joint is -35° to 35°. The pitch range of the PIP joint is 0°~90°; The DIP joint has a pitch range of 0° to 90°.

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