CN216030859U

CN216030859U - Three-joint linear parallel clamping self-adaptive under-actuated robot finger device

Info

Publication number: CN216030859U
Application number: CN202121601678.7U
Authority: CN
Inventors: 董尹凯; 张文增
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-07-14
Filing date: 2021-07-14
Publication date: 2022-03-15
Anticipated expiration: 2031-07-14

Abstract

Three-joint linear parallel clamp self-adaptive under-actuated robot finger device belongs to the technical field of robot hands, and comprises a base, a motor, a transmission mechanism, three finger sections, three joint shafts, eight connecting rods, four spring pieces, two limiting blocks and the like. The device can realize three-joint linear parallel clamping and double-finger-section self-adaptive grabbing modes. In the initial stage, the device is in a straight-line parallel clamping mode: the far finger section translates and the track is a straight line, so that the far finger section is suitable for clamping an object on a plane; when the near finger section is blocked from contacting the object, the device enters an adaptive grabbing mode: the middle finger section and the far finger section respectively rotate around a middle joint shaft and a far joint shaft; when the middle finger section contacts the object, the far finger section can continue to rotate until the near finger section, the middle finger section and the far finger section all contact the object. The device has the self-adaptability to different shapes and sizes of objects, adopts a motor to drive three joints, is stable in grabbing and has the effect of changing the grabbing force, and is simple to control and low in manufacturing and maintenance cost.

Description

Three-joint linear parallel clamping self-adaptive under-actuated robot finger device

Technical Field

The utility model belongs to the technical field of robot hands, and particularly relates to a structural design of a three-joint linear parallel clamping self-adaptive under-actuated robot finger device.

Background

The development and application of robotics are the current research focus. Researchers play a huge role in industrial production for research results of industrial robots, and the robots are controlled to execute repeated and dangerous operations, so that the intelligent factory and the unmanned factory are formed, and the production efficiency is greatly improved. Similar to industrial robots, service robots that walk into thousands of households and various occasions will become the next standardized product category, requiring the robot hand to assist in performing the gripping operation. Therefore, research on the robot hand becomes a hot point of research.

Since the human hand is a smart end fitting produced by man in the course of natural evolution. The motion of human hand has multiple modes of grabbing, including accurate end clamping (pinching) and multi-finger strength type holding, and the grabbing force is large. Multi-fingered robotic hands that mimic human hands are difficult to design.

The existing research field of multi-finger robot hands mainly comprises two robot hands based on different concepts. The first is a dexterous hand with a plurality of degrees of freedom controlled by a plurality of motors, and the other is an underactuated hand with a plurality of degrees of freedom driven by a small number of motors.

A dexterous hand generally has 3-5 fingers, each finger has 2-4 joint degrees of freedom, and most joints of the dexterous hand are active joints driven by motors, air cylinders or hydraulic cylinders and the like. The dexterous hand has higher grabbing precision. For example, the Robonaut hand developed by the united states space and navigation agency has 5 fingers and 14 joint degrees of freedom, realizes the driving control function through 14 motors and 12 independent control circuit boards, and has been applied to the dangerous environment of the space and ground track and the planet exploration task. The position of a grabbed object needs to be judged in advance in the grabbing process by a dexterous hand, path planning is carried out, a real-time control system formed by a plurality of motors is used for controlling, the control difficulty is high, and the cost is high.

The under-actuated hand reduces the use number of motors, so that the requirements on a real-time hand control and sensing system are greatly reduced while the anthropomorphic action of the robot hand is ensured. Existing under-actuated fingers include flat-grip fingers, coupled fingers, and adaptive fingers. The tail ends of the parallel clamping fingers keep a constant posture relative to the base in the grabbing process and are suitable for grabbing objects on the table top; when the near finger section of the coupling finger rotates, the far finger section can rotate relative to the near finger section simultaneously, so that the grabbing action is more anthropomorphic, and the grabbing is quicker; the self-adaptive finger proximal joint rotates firstly, the proximal finger section contacts an object and then triggers the next joint to rotate, and the rest is done by analogy until the terminal finger section contacts the object, so that the enveloping grabbing effect that a plurality of finger sections all contact the object is realized, and the self-adaptive finger proximal joint adapts to objects with different shapes and sizes. This adaptive gripping feature is not possible with conventional parallel grip fingers or coupled fingers.

The parallel clamping self-adaptive finger is a composite grabbing type finger which is generated by combining parallel clamping and self-adaptive grabbing functions in two time stages in tandem. The coupled adaptive finger is another composite grabbing finger combining coupled grabbing and adaptive grabbing.

Traditional parallel clamp self-adaptation finger is that the end is the parallel clamp self-adaptation finger of circular arc orbit, can't realize that the end is the parallel clamp self-adaptation complex of straight line orbit and snatchs the mode, when snatching desktop object, need arm cooperation control collaborative work just can realize that more accurate object snatchs, it is troublesome to bring for mechanical arm control, when snatching not equidimension object simultaneously, the device need highly carry out the operation at the difference, otherwise take place the device's end finger and desktop danger of colliding mutually easily.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects of the prior art and provides a three-joint linear parallel clamping self-adaptive under-actuated robot finger device. The device has three joints, has the function of parallel clamping of the straight track of the tail end finger segment, can realize the self-adaptive grabbing mode of the double finger segments of the middle finger segment and the far finger segment, and has self-adaptability to objects with different shapes and sizes.

The technical scheme of the utility model is as follows:

the utility model relates to a three-joint linear parallel clamp self-adaptive under-actuated robot finger device which comprises a base, a motor, a transmission mechanism, a near finger section, a middle finger section, a far finger section, a near joint shaft, a middle joint shaft and a far joint shaft; the motor is fixedly connected with the base and is connected with the input end of the transmission mechanism; the near joint shaft is sleeved in the base, the near finger section is sleeved on the near joint shaft, the middle joint shaft is sleeved in the near finger section, the middle finger section is sleeved on the middle joint shaft, the far joint shaft is sleeved in the middle finger section, and the far finger section is sleeved on the far joint shaft; the central lines of the proximal joint shaft, the middle joint shaft and the distal joint shaft are parallel to each other; the method is characterized in that: the three-joint linear parallel clamping self-adaptive under-actuated robot finger device further comprises a transition shaft, a first gear, a second gear, a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod, a fifth connecting rod, a sixth connecting rod, a seventh connecting rod, an eighth connecting rod, a first shaft, a second shaft, a third shaft, a fourth shaft, a fifth shaft, a sixth shaft, a first spring piece, a second spring piece, a third spring piece, a fourth spring piece, a first limiting block and a second limiting block; the transition shaft is sleeved in the base, the first gear is sleeved on the transition shaft, and the output end of the transmission mechanism is connected with the first gear; the second gear is sleeved on the proximal joint shaft and is meshed with the first gear; the central lines of the transition shaft, the first shaft, the second shaft, the third shaft, the fourth shaft, the fifth shaft, the sixth shaft and the near joint shaft are mutually parallel; the first connecting rod is sleeved on the proximal joint shaft, the first shaft is sleeved in the first connecting rod, the second connecting rod is sleeved on the first shaft, the second shaft is sleeved in the second connecting rod, and the middle finger section is sleeved on the second shaft; the third connecting rod is sleeved on the proximal joint shaft, and the third shaft is sleeved in the third connecting rod; the fourth connecting rod is sleeved on the third shaft, and the fourth shaft is sleeved in the fourth connecting rod; one end of the fifth connecting rod is sleeved on the middle joint shaft, and the other end of the fifth connecting rod is sleeved on the fourth shaft; the sixth connecting rod is sleeved on a fourth shaft, the fifth shaft is sleeved in the sixth connecting rod, and the far finger section is sleeved on the fifth shaft; the seventh connecting rod is sleeved on the proximal joint shaft, and the sixth shaft is sleeved in the seventh connecting rod; one end of the eighth connecting rod is sleeved on the sixth shaft, and the other end of the eighth connecting rod is sleeved on the fourth shaft; two ends of the first spring piece are respectively connected with the second gear and the seventh connecting rod; two ends of the second spring are respectively connected with the first connecting rod and the base; two ends of the third spring are respectively connected with the third connecting rod and the base; two ends of the fourth spring are respectively connected with the middle finger section and the far finger section; the first limiting block and the second limiting block are fixedly connected with the base respectively; in an initial state, the first connecting rod is in contact with the first limiting block, and the third connecting rod is in contact with the second limiting block; the central points of the near joint shaft, the middle joint shaft, the far joint shaft, the first shaft, the second shaft, the third shaft, the fourth shaft and the fifth shaft are A, B, C, D, E, F, G, H; the length of the line segment AF, the length of the line segment BG and the length of the line segment CH are equal; the length of the line segment AB is equal to the length of the line segment FG; the length of segment GH is equal to the length of segment BC; the length relation of the line segment AD, the line segment DE, the line segment BE, the line segment BC, the line segment EC and the line segment AB meets the following requirements: AD: BE: BC: CE: AB: 68:51:49:68:110: 100.

The utility model relates to a three-joint linear parallel clamping self-adaptive under-actuated robot finger device, which is characterized in that: the transmission mechanism comprises a speed reducer, a worm and a worm wheel; the output shaft of the motor is connected with the input shaft of the speed reducer; the worm is fixedly sleeved on an output shaft of the speed reducer; the worm wheel is fixedly sleeved on the transition shaft, and the first gear is fixedly connected with the transition shaft; the worm is engaged with the worm wheel.

The utility model relates to a three-joint linear parallel clamping self-adaptive under-actuated robot finger device, which is characterized in that: the first spring piece adopts a tension spring, a pressure spring or a torsion spring; the second spring piece adopts a tension spring, a pressure spring or a torsion spring; the third spring piece adopts a tension spring, a pressure spring or a torsion spring; the fourth spring piece adopts a tension spring, a pressure spring or a torsion spring.

Compared with the prior art, the utility model has the following advantages and prominent effects:

the device adopts base, motor, drive mechanism, three finger section, three joint shaft, eight connecting rods, four spring spare and two stoppers etc. to synthesize and realized three joint straight line parallel clamps and two finger section self-adaptation modes of snatching. In the initial stage, the device is in a straight-line parallel clamping mode: the far finger section translates and the track is a straight line, so that the far finger section is suitable for clamping an object on a plane; when the near finger section is blocked from contacting the object, the device enters an adaptive grabbing mode: the middle finger section and the far finger section respectively rotate around a middle joint shaft and a far joint shaft; when the middle finger section contacts the object, the far finger section can continue to rotate until the near finger section, the middle finger section and the far finger section all contact the object. The device has the self-adaptability to different shapes and sizes of objects, adopts a motor to drive three joints, is stable in grabbing and has the effect of changing the grabbing force, and is simple to control and low in manufacturing and maintenance cost.

Drawings

Fig. 1 is a perspective external view of an embodiment of a three-joint linear parallel clamping self-adaptive under-actuated robot finger device designed by the utility model.

Fig. 2-3 are perspective views of the embodiment of fig. 1 (not shown with some parts).

Fig. 4 is a front view of the embodiment shown in fig. 1.

Fig. 5 is a front view of the embodiment of fig. 1 (not shown with parts).

Fig. 6 is a rear view of the embodiment of fig. 1 (not shown with some parts).

Fig. 7 is a left side view of the embodiment shown in fig. 1.

Fig. 8 is a left side view of the embodiment of fig. 1 (not shown with some parts).

Fig. 9 is a right side view of the embodiment of fig. 1 (not shown with some parts).

Fig. 10 is a schematic diagram of a portion of the mechanism in the embodiment of fig. 1.

Fig. 11 is a schematic mechanical diagram of the embodiment shown in fig. 1.

Fig. 12 is a process of linear parallel clamping operation of the embodiment of fig. 1.

Fig. 13-14 are diagrams of the embodiment of the dual finger segment adaptive action process shown in fig. 1.

In fig. 1 to 14:

10-base, 11-motor, 12-reducer, 13-worm,

14-worm wheel, 15-transition shaft, 16-first gear, 17-second gear,

21-proximal finger section, 22-middle finger section, 23-distal finger section, 31-proximal joint axis,

32-central joint axis, 33-distal joint axis, 34-first axis, 35-second axis,

36-third axis, 37-fourth axis, 38-fifth axis, 39-sixth axis,

41-a first link, 42-a second link, 43-a third link, 44-a fourth link,

45-a fifth connecting rod, 46-a sixth connecting rod, 47-a seventh connecting rod, 48-an eighth connecting rod,

51-a first spring member, 52-a second spring member, 53-a third spring member, 54-a fourth spring member,

61-a first stopper, 62-a second stopper, 7-an object.

Detailed Description

The details of the structure and the operation principle of the present invention are further described in detail below with reference to the accompanying drawings and embodiments.

One embodiment of the three-joint linear parallel clamp self-adaptive under-actuated robot finger device designed by the utility model is shown in fig. 1 to 9 and comprises a base 10, a motor 11, a transmission mechanism, a proximal finger section 21, a middle finger section 22, a distal finger section 23, a proximal joint shaft 31, a middle joint shaft 32 and a distal joint shaft 33; the motor 11 is fixedly connected with the base 10, and the motor 11 is connected with the input end of the transmission mechanism; the proximal joint shaft 31 is sleeved in the base 10, the proximal finger section 21 is sleeved on the proximal joint shaft 31, the middle joint shaft 32 is sleeved in the proximal finger section 21, the middle finger section 22 is sleeved on the middle joint shaft 32, the distal joint shaft 33 is sleeved in the middle finger section 22, and the distal finger section 23 is sleeved on the distal joint shaft 33; the central lines of the proximal joint shaft 31, the middle joint shaft 32 and the distal joint shaft 33 are parallel to each other; the method is characterized in that: the three-joint linear parallel clamp self-adaptive under-actuated robot finger device further comprises a transition shaft 15, a first gear 16, a second gear 17, a first connecting rod 41, a second connecting rod 42, a third connecting rod 43, a fourth connecting rod 44, a fifth connecting rod 45, a sixth connecting rod 46, a seventh connecting rod 47, an eighth connecting rod 48, a first shaft 34, a second shaft 35, a third shaft 36, a fourth shaft 37, a fifth shaft 38, a sixth shaft 39, a first spring element 51, a second spring element 52, a third spring element 53, a fourth spring element 54, a first limiting block 61 and a second limiting block 62; the transition shaft 15 is sleeved in the base 10, the first gear 16 is sleeved on the transition shaft 15, and the output end of the transmission mechanism is connected with the first gear 16; the second gear 17 is sleeved on the proximal joint shaft 31, and the second gear 17 is meshed with the first gear 16; the central lines of the transition shaft 15, the first shaft 34, the second shaft 35, the third shaft 36, the fourth shaft 37, the fifth shaft 38, the sixth shaft 39 and the proximal joint shaft 31 are parallel to each other; the first connecting rod 41 is sleeved on the proximal joint shaft 31, the first shaft 34 is sleeved in the first connecting rod 41, the second connecting rod 42 is sleeved on the first shaft 34, the second shaft 35 is sleeved in the second connecting rod 42, and the middle finger section 22 is sleeved on the second shaft 35; the third connecting rod 43 is sleeved on the proximal joint shaft 31, and the third shaft 36 is sleeved in the third connecting rod 43; the fourth connecting rod 44 is sleeved on the third shaft 36, and the fourth shaft 37 is sleeved in the fourth connecting rod 44; one end of the fifth connecting rod 45 is sleeved on the middle joint shaft 32, and the other end of the fifth connecting rod 45 is sleeved on the fourth shaft 37; the sixth connecting rod 46 is sleeved on the fourth shaft 37, the fifth shaft 38 is sleeved in the sixth connecting rod 46, and the far finger section 23 is sleeved on the fifth shaft 38; the seventh connecting rod 47 is sleeved on the proximal joint shaft 31, and the sixth shaft 39 is sleeved in the seventh connecting rod 47; one end of the eighth connecting rod 48 is sleeved on the sixth shaft 39, and the other end of the eighth connecting rod 48 is sleeved on the fourth shaft 37; two ends of the first spring element 51 are respectively connected with the second gear 17 and the seventh connecting rod 47; the two ends of the second spring element 52 are respectively connected with the first connecting rod 41 and the base 10; two ends of the third spring 53 are respectively connected with the third connecting rod 43 and the base 10; the two ends of the fourth spring element 44 are respectively connected with the middle finger section 22 and the far finger section 23; the first limiting block 61 and the second limiting block 62 are fixedly connected with the base respectively; in an initial state, the first link 41 contacts with the first stopper 61, and the third link 43 contacts with the second stopper 62; let the central point of the proximal joint axis 31, the middle joint axis 32, the distal joint axis 33, the first axis 34, the second axis 35, the third axis 36, the fourth axis 37 and the fifth axis 38 be A, B, C, D, E, F, G, H; the length of the line segment AF, the length of the line segment BG and the length of the line segment CH are equal; the length of the line segment AB is equal to the length of the line segment FG; the length of segment GH is equal to the length of segment BC; the length relation of the line segment AD, the line segment DE, the line segment BE, the line segment BC, the line segment EC and the line segment AB meets the following requirements: AD: BE: BC: CE: AB: 68:51:49:68:110: 100.

In the present embodiment, the transmission mechanism includes a speed reducer 12, a worm 13, and a worm wheel 14; the output shaft of the motor 11 is connected with the input shaft of the speed reducer 12; the worm 13 is fixedly sleeved on an output shaft of the speed reducer 12; the worm wheel 14 is fixedly sleeved on the transition shaft 15, and the first gear 16 is fixedly connected with the transition shaft 15; the worm 13 meshes with a worm wheel 14.

The utility model relates to a three-joint linear parallel clamping self-adaptive under-actuated robot finger device, which is characterized in that: the first spring piece 51 adopts a tension spring, a compression spring or a torsion spring; the second spring piece 52 adopts a tension spring, a pressure spring or a torsion spring; the third spring piece 53 adopts a tension spring, a pressure spring or a torsion spring; the fourth spring 54 is a tension spring, a compression spring or a torsion spring. In the present embodiment, the first spring element 51 is a torsion spring, the second spring element 52 is a tension spring, the third spring element 53 is a tension spring, and the fourth spring element 54 is a tension spring.

The working principle of the embodiment is described as follows with reference to the attached drawings:

the initial state of this embodiment is shown in fig. 1.

The principle of the point E moving along the straight track by the proximal finger section 21, the middle finger section 22, the first link 41, the second link 42, the proximal joint shaft 31, the middle joint shaft 32, the distal joint shaft 33, the first shaft 34, the second shaft 35, and the like in this embodiment is shown in fig. 10. When the line segment AB rotates around the line segment A, the line segment DE can be driven to rotate around the point D, and the point C moves along the track of the straight line S. The center point C of the distal joint axis is at C₁And C₂The motion between the two tracks is approximately a straight line.

In the initial state of the present embodiment, under the action of the second spring element 52 and the third spring element 53, the first link 41 contacts the first stopper 61, and the third link 43 contacts the second stopper 62.

When the present embodiment performs the grasping operation, there are two grasping modes: a straight line parallel clamping mode and a double-finger section self-adaptive envelope grabbing mode. The working principle is described as follows.

(1) Linear parallel clamping grabbing mode

The motor 11 rotates, the second gear 17 is driven to rotate through the speed reducer 12, the seventh connecting rod 37 is driven to rotate through the first spring element 51, and the proximal section 21 is driven to rotate through the eighth connecting rod 38 and the fifth connecting rod 35. Since the end of the mechanism composed of the proximal finger section 21, the middle finger section 22, the first link 41 and the second link 42 moves along an approximately straight line, the distal joint shaft 33 moves along a straight line relative to the base 10; since the proximal finger section 21, the third link 43, the fourth link 44, and the fifth link 45 constitute a parallel four-link mechanism, the line segment AF in fig. 11 is parallel to the line segment BG; the middle finger section 22, the fifth link 45, the sixth link 46, and the far finger section 23 also constitute a parallel four-bar linkage, so the line segment BG in fig. 11 is parallel to the line segment CH, which is parallel to the line segment AF. In the process of starting movement from the initial state, the first link 41 is kept in contact with the first stopper 61 under the action of the second spring element 52, and the third link 43 is kept in contact with the second stopper 62 under the action of the third spring element 53, so that the first link 41 and the third link 43 are kept fixed relative to the base 10, so that the distal finger section 23 is kept in a constant posture relative to the base 10 in the process, and therefore, the distal finger section 23 is translated along an approximately linear track in the process of movement.

The process is called a linear parallel clamping motion process. In the process, when the distal finger section 23 contacts the object 7, the grasping is finished, and the function of straight-line flat clamping of the object is realized, as shown in fig. 12.

After the far finger section 23 contacts the object 7, the motor 11 continues to rotate, the deformation amount of the first spring element 51 is increased, the gripping force on the object is increased, and the effect of variable gripping force adjustment is achieved.

(2) Adaptive grab mode

According to different grabbing situations, there are two adaptive grabbing modes: the adaptive grabbing mode of the middle finger segment and the adaptive grabbing mode of the far finger segment.

In the process of the linear parallel clamping movement, when the near finger section 21 firstly contacts the object 7, the near finger section 21 is blocked and cannot rotate any further, and at the moment, a middle and far double-finger section self-adaptive grabbing mode is executed. The motor 11 continues to rotate, which drives the seventh link 47 to rotate, and the eighth link 48 rotates the fifth link 45 around the middle joint shaft 32. Since the proximal segment 21, the third link 43, the fourth link 44 and the fifth link 45 form a parallel four-bar linkage, the third link 43 leaves the second stopper 62 and rotates around the proximal joint shaft 31 by a corresponding angle, and the third spring 53 is stretched. The middle finger section 22, the fifth connecting rod 45, the sixth connecting rod 46 and the far finger section 23 also form a parallel four-bar linkage, the far finger section 23 can rotate by a corresponding angle around the far joint shaft 33, the middle finger section 22 and the far finger section 23 can rotate together around the middle joint shaft 32 under the action of the fourth spring piece 54, the included angle between the first connecting rod 41 and the second connecting rod 42 is increased, the first connecting rod 41 leaves the first limiting block 61, and the second spring piece 52 is stretched until the middle finger section 22 contacts an object, so that the middle finger section self-adaptive grabbing mode is realized.

After the middle finger section 22 contacts the object 7, the middle finger section is fixed, the motor 11 rotates, the seventh connecting rod 47 pushes the fifth connecting rod 45 to continue rotating through the eighth connecting rod 48, the distal finger section 23 rotates around the distal joint shaft 33, the first spring element 51 and the fourth spring element 54 are stretched until the distal finger section 23 contacts the object 7, and the distal finger section self-adaptive grabbing mode is realized.

The above process comprehensively realizes the near and middle finger segment self-adaptive grabbing mode, and the process has self-adaptability to objects with different shapes and sizes, as shown in fig. 13 and 14.

In the process of the linear parallel clamping movement, when the middle finger section 22 contacts the object 7 first, the near finger section 21 and the middle finger section 22 are both fixed, and at this time, only the far finger section adaptive grabbing mode is executed, and the grabbing principle is consistent with the far finger section adaptive grabbing mode in the near and middle finger section adaptive grabbing mode, and is not repeated.

The process of releasing the object 7 is the reverse of the above process and will not be described in detail.

Claims

1. A three-joint linear flat clip adaptive underactuated robot finger device, comprising a base, a motor, a transmission mechanism, a proximal finger segment, a middle finger segment, a distal finger segment, a proximal joint axis, a middle joint axis and a distal joint axis; The motor is fixedly connected to the base, and the motor is connected to the input end of the transmission mechanism; the proximal joint shaft is sleeved in the base, the proximal finger segment is sleeved on the proximal joint shaft, and the middle joint shaft is sleeved Set in the proximal finger segment, the middle finger segment is sleeved on the middle joint shaft, the distal joint shaft is sleeved in the middle finger segment, and the distal finger segment is sleeved on the distal joint shaft; the proximal joint shaft, The center lines of the mid-joint shaft and the far-joint shaft are parallel to each other; it is characterized in that the three-joint linear flat clip adaptive underactuated robot finger device further comprises a transition shaft, a first gear, a second gear, a first link, a second Connecting rod, third connecting rod, fourth connecting rod, fifth connecting rod, sixth connecting rod, seventh connecting rod, eighth connecting rod, first shaft, second shaft, third shaft, fourth shaft, first shaft The fifth axis, the sixth axis, the first spring member, the second spring member, the third spring member, the fourth spring member, the first limit block and the second limit block; the transition shaft is sleeved in the base, The first gear is sleeved on the transition shaft, and the output end of the transmission mechanism is connected with the first gear; the second gear is sleeved on the proximal joint shaft, and the second gear is meshed with the first gear; The centerlines of the transition axis, the first axis, the second axis, the third axis, the fourth axis, the fifth axis, the sixth axis and the proximal joint axis are parallel to each other; the first connecting rod is sleeved on the proximal joint axis , the first shaft is sleeved in the first connecting rod, the second connecting rod is sleeved on the first shaft, the second shaft is sleeved in the second connecting rod, and the middle finger is sleeved on the on the second shaft; the third connecting rod is sleeved on the proximal joint shaft, and the third shaft is sleeved in the third connecting rod; the fourth connecting rod is sleeved on the third shaft, and the first connecting rod is sleeved on the third shaft. The four shafts are sleeved on the fourth connecting rod; one end of the fifth connecting rod is sleeved on the middle joint shaft, and the other end of the fifth connecting rod is sleeved on the fourth shaft; the sixth connecting rod is sleeved on the fourth shaft; On the fourth shaft, the fifth shaft is sleeved on the sixth connecting rod, the distal finger segment is sleeved on the fifth shaft; the seventh connecting rod is sleeved on the proximal joint shaft, and the sixth connecting rod is sleeved on the proximal joint shaft. The six shafts are sleeved on the seventh connecting rod; one end of the eighth connecting rod is sleeved on the sixth shaft, and the other end of the eighth connecting rod is sleeved on the fourth shaft; The ends are respectively connected with the second gear and the seventh connecting rod; the two ends of the second spring element are respectively connected with the first connecting rod and the base; the two ends of the third spring element are respectively connected with the third connecting rod and the base; Two ends of the fourth spring element are respectively connected to the middle finger segment and the distal finger segment; the first limit block and the second limit block are respectively fixed to the base; in the initial state, the first link is connected to the base. The first limit block is in contact, and the third link is in contact with the second limit block; the proximal joint axis, the middle joint axis, the distal joint axis, the first axis, the second axis, the third axis, the fourth axis and the The center points of the fifth axis are A, B, C, D, E, F, G, H; the length of the line segment AF, the length of the line segment BG and the length of the line segment CH are equal; the length of the line segment AB is equal to the length of the line segment FG; the line segment The length of GH is equal to the length of line BC; line AD, line DE, line BE, line BC, line The length relationship between segment EC and line segment AB satisfies: AD:DE:BE:BC:CE:AB=68:51:49:68:110:100.

2. The three-joint linear flat clip adaptive underactuated robot finger device according to claim 1, wherein the transmission mechanism comprises a reducer, a worm and a worm wheel; the output shaft of the motor and the input shaft of the reducer The worm is sleeved on the output shaft of the reducer; the worm gear is sleeved on the transition shaft, the first gear is fixed with the transition shaft; the worm is meshed with the worm gear.

3 . The three-joint linear flat clip adaptive underactuated robot finger device according to claim 1 , wherein the first spring member adopts a tension spring, a compression spring or a torsion spring; the second spring member adopts a tension spring. 4 . spring, compression spring or torsion spring; the third spring member adopts tension spring, compression spring or torsion spring; the fourth spring member adopts tension spring, compression spring or torsion spring.