CN109664322B

CN109664322B - Self-adaptive under-actuated finger device based on connecting rod transmission

Info

Publication number: CN109664322B
Application number: CN201910071957.8A
Authority: CN
Inventors: 王道明; 熊焰; 訾斌; 钱森; 王正雨; 陈兵; 黄子桐
Original assignee: Hefei University of Technology
Current assignee: Hefei University of Technology
Priority date: 2019-01-25
Filing date: 2019-01-25
Publication date: 2021-08-06
Anticipated expiration: 2039-01-25
Also published as: CN109664322A

Abstract

The invention relates to a self-adaptive under-actuated finger device based on connecting rod transmission, which comprises a near finger component, a middle finger component and a far finger component which are sequentially arranged and hinged, wherein the near finger component comprises a near knuckle shell, a near knuckle connecting rod, a base joint support fixed on a palm of a dexterous hand, a connecting rod in sliding connection with the base joint support, a driving bevel gear connected with a direct-current servo motor, an angle sensor and a gear rack self-adapting mechanism, the middle finger component comprises a middle knuckle shell and a middle knuckle connecting rod, the far finger component comprises a far knuckle shell, a far knuckle upper end cover and a far knuckle connecting rod, and the bottom of the far knuckle shell is provided with a film touch force sensor. According to the technical scheme, the tail end of the robot is high in grabbing capacity, has the advantages of being good in self-adaptability, simple in structure, light in weight, simple to control, low in cost and the like, and can meet requirements of stable grabbing and flexible operation of a dexterous hand.

Description

Self-adaptive under-actuated finger device based on connecting rod transmission

Technical Field

The invention relates to the field of robots, in particular to a self-adaptive under-actuated finger device based on connecting rod transmission.

Background

With the development of intelligent technology and manufacturing industry, the application field of the robot is more and more extensive. Conventional industrial robots are widely used in manufacturing industries, but in non-manufacturing industries, such as marine development, medical treatment, service, entertainment and the like, the operating environment is often diverse and complex, which requires more powerful, flexible and adaptable end effectors for machine configuration, thus prompting students to develop research on dexterous simulated hands.

At present, most of humanoid Dexterous hands are full-drive multi-finger Dexterous hands, such as Robonaut hands, Shadow Dexterous hands, UBV and the like, although the grabbing and partial operation tasks of objects can be realized, a control system is complex, high in cost and large in mass and volume, and the actual application space of the humanoid Dexterous hands is greatly limited. Compared with the human-simulated under-actuated dexterous hand, the human-simulated under-actuated dexterous hand has the characteristics of simple mechanism, small mass, small volume, simple control, high reliability and flexible operation.

The under-actuated multi-finger dexterous hand is classified according to the working mode and mainly comprises a coupling under-actuated dexterous hand and a self-adaptive under-actuated dexterous hand. Coupling a smart underactuated dexterous hand, such as: the Belgrade/USC Hand enables the movement of each joint of the finger to be coupled through a coupling mechanism, so that the degree of freedom of the finger is reduced, the finger tip has determined movement, the movement is accurate, the control is simple, the grabbing force is large, and the Belgrade/USC Hand cannot adapt to the shapes of different objects; and self-adaptive under-actuated dexterous hand, such as: DSUA Hand can adapt to the shape of different objects, but because the joint fingertip passes through the spring coupling, the fingertip rigidity is very low, only is suitable for palm envelope to snatch, and the fingertip snatchs the ability very weakly.

Disclosure of Invention

The invention aims to provide a self-adaptive under-actuated finger device based on connecting rod transmission, which has the advantages of strong tail end grabbing capacity, good self-adaptability, simple structure, light weight, simplicity in control, low cost and the like, and can meet the requirements of stable grabbing and smart operation of a dexterous hand.

In order to achieve the purpose, the invention adopts the following technical scheme: the finger-joint type flexible hand comprises a near finger assembly, a middle finger assembly and a far finger assembly which are sequentially arranged and hinged, wherein the near finger assembly comprises a near knuckle shell, a near knuckle connecting rod, a base joint support fixed on a palm of the flexible hand, a connecting rod in sliding connection with the base joint support, a driving bevel gear connected with a direct-current servo motor, an angle sensor and a gear rack self-adaption mechanism; the two ends of the near knuckle shell and the near knuckle connecting rod are respectively connected through a first rotating shaft and a second rotating shaft, the driving bevel gear, the base joint support and the angle sensor are coaxially arranged with the first rotating shaft, a straight gear in the gear rack self-adaption mechanism is coaxially arranged with the second rotating shaft, one end of the connecting rod is in sliding fit with the base joint support, the other end of the connecting rod is fixed on the second rotating shaft, the two ends of the middle knuckle shell are respectively connected through the second rotating shaft and the first pin shaft, the two ends of the far knuckle shell and the far knuckle upper end cover are respectively connected through the first pin shaft and the second pin shaft, one end of the middle knuckle connecting rod is fixed on the second rotating shaft, the other end of the middle knuckle connecting rod is fixed on the first pin shaft, one end of the far knuckle connecting rod is connected with the second pin shaft, and the other end of the far knuckle connecting rod is in sliding fit with the near knuckle connecting rod, the middle part of the far knuckle connecting rod is connected with a first pin shaft, the gear rack self-adapting mechanism comprises a near knuckle sliding block body, a rack arranged on the near knuckle sliding block body and a straight gear which is fixed on a second rotating shaft and is matched with the rack, the bottom surface of the near knuckle sliding block body is a rectangular plane with the same width as the fingers, a second waist-shaped notch arranged in the vertical direction is arranged on the near knuckle sliding block body, the gear rack self-adaptive mechanism also comprises a first round head pin and a second round head pin which are arranged in the vertical direction and vertically penetrate through the third lug plate and the fourth lug plate, the first round-head pin and the second round-head pin are respectively provided with a first miniature bearing and a second miniature bearing, the first miniature bearing and the second miniature bearing are positioned in the second kidney-shaped notch, and the proximal knuckle slider body can slide on the first micro bearing and the second micro bearing along the direction defined by the second kidney-shaped notch.

The base joint support comprises a first support plate and a second support plate which are parallel to a near knuckle connecting rod, wherein a base for connecting the first support plate and the second support plate is arranged at the bottom of the first support plate and the second support plate, one end of the base is flush with the end surface of the first support plate, the length of the base is larger than the distance between the first support plate and the second support plate, the first support plate is positioned between a drive bevel gear and a first lug plate, the second support plate is positioned between a second lug plate and an angle sensor, a plate body connected with the connecting rod extends leftwards from the second support plate, the plate body and the second support plate are of an integrated structure, a first external threaded cylindrical pin is arranged at the end part of the plate body, a first bearing is arranged on the first external threaded cylindrical pin, a first waist-shaped notch matched with the first bearing is arranged at one end of the connecting rod, and the first bearing slides in the range limited by the first waist-shaped notch, the other end of the connecting rod is hinged with the second rotating shaft.

The near knuckle shell is arranged in parallel with the near knuckle connecting rod, and the driving bevel gear is positioned between a first lug plate and a second lug plate formed at the right end of the near knuckle connecting rod; the gear rack self-adaption mechanism is arranged between a third lug plate and a fourth lug plate formed at the left end of the near knuckle connecting rod, a through groove matched with the gear rack self-adaption mechanism in shape is formed between the third lug plate and the fourth lug plate, an extension plate in sliding fit with the far knuckle connecting rod is extended leftwards and downwards at the end part of the fourth lug plate, and a third waist-shaped notch is formed in the extension plate; the middle knuckle shell comprises a first rib plate and a second rib plate which are arranged in parallel in the vertical direction, the bottoms of the first rib plate and the second rib plate are connected through a bottom plate, the far knuckle shell comprises a third rib plate and a fourth rib plate which are arranged in parallel, connecting plates are arranged at the front sides and the bottom sides of the third rib plate and the fourth rib plate in a surrounding mode, the far knuckle upper end cover comprises a fifth rib plate and a sixth rib plate which are arranged in parallel, top plates for connecting the fifth rib plate and the sixth rib plate are arranged on the upper plate surfaces of the fifth rib plate and the sixth rib plate, the fifth rib plate and the sixth rib plate are respectively located on the outer sides of the third rib plate and the fourth rib plate, and the far knuckle connecting rod is arranged between the third rib plate and the fourth rib plate.

First pivot including arrange in proper order and first shaft part, second shaft part, third shaft part and the fourth shaft part as an organic whole structure, wherein: the first shaft section is matched with the first lug plate and the first support plate, the second shaft section is matched with the driving bevel gear and the second support plate, the third shaft section is matched with the angle sensor, the fourth shaft section is matched with the near knuckle shell, the part of the second shaft section, which is matched with the driving bevel gear, and the third shaft section are D-shaped shafts, the end parts of the first shaft section and the fourth shaft section are provided with elastic check rings for shafts, and the first rotating shaft is sequentially connected with the first lug plate, the first support plate, the driving bevel gear, the second lug plate, the second support plate, the angle sensor and the near knuckle shell.

The second pivot including arrange in proper order and fifth axial segment, sixth axial segment and the seventh axial segment of structure as an organic whole, fifth axial segment and third otic placode, the first floor of middle knuckle shell, spur gear cooperate, sixth axial segment and fourth otic placode and middle knuckle connecting rod cooperate, the second floor and the nearly knuckle shell of seventh axial segment and connecting rod, middle knuckle shell cooperate, wherein: fifth shaft section is D type axle with first floor and the straight-teeth gear matched with position of well knuckle shell, sixth shaft section is D type axle with well knuckle connecting rod matched with position, the second pivot second floor and the nearly knuckle shell of connecting gradually the first floor, straight-teeth gear, fourth floor, well knuckle connecting rod, the well knuckle shell of third otic placode, well knuckle shell, and the one end that the second pivot is close to nearly knuckle shell is equipped with the circlip for the axle.

A columnar boss for mounting a torsion spring is arranged on the end face of the second rib plate of the connecting rod, which is close to the middle knuckle shell, one end of the torsion spring is fixed with a first clamping groove arranged on the second rib plate, and the other end of the torsion spring is fixed with a second clamping groove arranged on the connecting rod; the connecting rod and the end face, close to the middle knuckle connecting rod, of the middle knuckle connecting rod are respectively provided with 120-degree annular bosses, the axial installation positions of the two annular bosses are staggered, the middle knuckle connecting rod is attached to the connecting rod in the axial direction in the initial state, and the middle knuckle connecting rod cannot rotate clockwise relative to the connecting rod under the limiting of the annular bosses.

The far knuckle connecting rod comprises a horizontal rod and an inclined rod extending towards the right lower direction along the end part of the horizontal rod, the horizontal rod and the inclined rod are of an integral structure, two ends of the horizontal rod are respectively connected with a second pin shaft and a first pin shaft, a second external thread cylindrical pin is arranged at the end part of the inclined rod, a second bearing is arranged on the second external thread cylindrical pin, and the second bearing and a third kidney-shaped notch form sliding fit.

The sensing system comprises a current sensor, an angle sensor fixed on a first rotating shaft and a film touch force sensor stuck on the lower side of the far knuckle shell, the sensing system is connected with a control board, and the control board acquires sensor signals to control the position and the moment of the direct current servo motor.

The angle sensor adopts an R24HS robot joint angle sensor, the central rotating shaft of the angle sensor is of a hollow structure, the film touch force sensor is an FSR402 film pressure sensor, and the current sensor is a WCS2801 current detection sensor.

The invention has the beneficial effects that: 1) the invention adopts the connecting rod transmission, can provide better force transmission effect, and avoids the defects of low transmission precision and pre-tightening requirement of the rope; 2) the invention not only has good fingertip grabbing capability, but also can adapt to the shapes of different objects to carry out grabbing operation, and has strong applicability; 3) the invention is provided with the angle sensor, the touch force sensor, the current sensor and the DC servo motor, can effectively control the movement and the grabbing force of the fingers, and provides possibility for the complex operation of the dexterous hand; 4) the invention adopts an underactuated mode of the direct current servo motor, effectively reduces the control difficulty, has simpler control, particularly adaptive grabbing, can effectively reduce the cost and broaden the application field of the system.

Drawings

FIG. 1 is a first perspective view of the present invention;

FIG. 2 is a schematic perspective view of the present invention;

FIG. 3 is a schematic view of an exploded structure of the present invention;

FIG. 4 is a top view of the present invention;

FIG. 5 is a first schematic diagram of the internal structure of the present invention;

FIG. 6 is a second schematic diagram of the internal structure of the present invention;

FIG. 7 is a schematic view of the construction of the base joint support of the present invention;

FIG. 8 is a schematic view of the construction of the connecting rod of the present invention;

FIG. 9 is a schematic view of the proximal knuckle link of the present invention;

FIG. 10 is a schematic structural view of a rack and pinion adaptive mechanism of the present invention;

FIG. 11 is a schematic view of the first shaft according to the present invention;

FIG. 12 is a schematic view of a second shaft according to the present invention;

FIG. 13 is a schematic view of the present invention performing a bending action;

fig. 14 is a control schematic of the present invention.

The figures of the above drawings are numbered:

the proximal phalanx assembly 1, the proximal phalanx housing 11, the proximal phalanx link 12, the first ear plate 121, the second ear plate 122, the third ear plate 123, the fourth ear plate 124, the extension plate 125, the third kidney-shaped notch 126, the through slot 127, the base joint support 13, the first support plate 131, the second support plate 132, the base 133, the plate 134, the link 14, the first kidney-shaped notch 141, the torsion spring 142, the columnar boss 143, the first catch 144, the second catch 145, the annular boss 146, the drive bevel gear 15, the angle sensor 16, the rack and pinion adaptive mechanism 17, the proximal phalanx slider body 171, the rack 172, the spur gear 173, the rectangular plane 174, the second kidney-shaped notch 175, the first round head pin 176, the second round head pin 177, the first micro bearing 178, the second micro bearing 179, the first externally threaded cylindrical pin 18, the first bearing 181, the middle finger assembly 2, the middle phalanx housing 21, the first rib plate 211, the second rib plate 212, the second rib plate 123, the first catch 124, the second catch 124, the cylindrical notch 126, the cylindrical pin 143, the cylindrical pin, the drive bevel gear 15, the angle sensor 16, the angle sensor 17, the gear, and the gear, The base plate 213, the middle knuckle connecting rod 22, the far knuckle assembly 3, the far knuckle housing 31, the third rib plate 311, the fourth rib plate 312, the connecting plate 313, the far knuckle upper end cover 32, the fifth rib plate 321, the sixth rib plate 322, the top plate 323, the far knuckle connecting rod 33, the horizontal rod 331, the diagonal rod 332, the second externally threaded cylindrical pin 34, the second bearing 341, the film touch force sensor 4, the first rotating shaft 51, the first shaft segment 511, the second shaft segment 512, the third shaft segment 513, the fourth shaft segment 514, the second rotating shaft 52, the fifth shaft segment 521, the sixth shaft segment 522, the seventh shaft segment 523, the first pin shaft 53, the second pin shaft 54, the current sensor 6, the control board 7 and the dc servo motor 8.

Detailed Description

The invention is further described below with reference to the accompanying drawings:

as shown in fig. 1, fig. 2, fig. 3, and fig. 4, the self-adaptive under-actuated finger device based on link transmission includes a proximal finger assembly 1, a middle finger assembly 2, and a distal finger assembly 3, which are sequentially arranged and hinged to each other, in this embodiment, the device is a schematic structural diagram of a single finger on a dexterous hand, and the proximal finger assembly 1, the middle finger assembly 2, and the distal finger assembly 3 respectively correspond to a proximal knuckle, a middle knuckle, and a distal knuckle of a human finger.

Further, the proximal finger assembly 1 comprises a proximal knuckle housing 11, a proximal knuckle connecting rod 12, a base joint support 13 fixed on the palm of the dexterous hand, a connecting rod 14 connected with the base joint support 13 in a sliding manner, a driving bevel gear 15 connected with a direct current servo motor, an angle sensor 16 and a gear rack self-adapting mechanism 17.

Wherein: as shown in fig. 7, the base joint support 13 includes a first support plate 131 and a second support plate 132 parallel to the proximal knuckle connecting rod 12, a base 133 connecting the first support plate 131 and the second support plate 132 is provided at the bottom of the two support plates, and the base 133 is fixed to the palm of the dexterous hand; one end of the base 133 is flush with the end surface of the first bracket plate 131, and the length of the base 133 is greater than the distance between the first bracket plate 131 and the second bracket plate 132, that is, the other end of the base 133 is located on the outer side surface of the second bracket plate 132; the first bracket plate 131 is located between the driving bevel gear 15 and the first lug plate 121, the second bracket plate 132 is located between the second lug plate 122 and the angle sensor 16, the second bracket plate 132 extends leftwards to form a plate 134 connected with the connecting rod 14, the plate 134 and the second bracket plate 132 are of an integral structure, the end of the plate 134 is provided with a first external threaded cylindrical pin 18, the first external threaded cylindrical pin 18 is provided with a first bearing 181, namely, the first external threaded cylindrical pin 18 is in threaded connection with the plate 134, the inner ring of the first bearing 181 is installed at the smooth end of the first external threaded cylindrical pin 18, as shown in fig. 8, one end of the connecting rod 14 is provided with a first kidney-shaped notch 141 matched with the first bearing 181, the first bearing 181 slides within the range defined by the first kidney-shaped notch 141, and the other end of the connecting rod 14 is hinged to the second rotating shaft 52. The proximal knuckle connecting rod 12, the plate 134, the first bearing 181 and the connecting rod 14 form a first set of slider link mechanisms, and when the proximal knuckle connecting rod 12 rotates by a certain angle, the connecting rod 14 rotates by a corresponding angle, so that the motion coupling of the proximal knuckle connecting rod 12 and the connecting rod 14 is realized.

As shown in fig. 9, the proximal knuckle housing 11 is disposed in parallel with the proximal knuckle connecting rod 12, and the driving bevel gear 15 is disposed between a first lug plate 121 and a second lug plate 122 formed at the right end of the proximal knuckle connecting rod 12; the rack-and-pinion adaptive mechanism 17 is disposed between a third ear plate 123 and a fourth ear plate 124 formed at the left end of the proximal knuckle connecting rod 12, a through groove 127 matched with the rack-and-pinion adaptive mechanism 17 in shape is formed between the third ear plate 123 and the fourth ear plate 124, an extending plate 125 forming a sliding fit with the distal knuckle connecting rod 33 extends leftwards and downwards from the end of the fourth ear plate 124, and a third kidney-shaped notch 126 is formed in the extending plate 125.

Further, as shown in fig. 10, the rack-and-pinion adaptive mechanism 17 includes a proximal knuckle slider body 171, a rack 172 disposed on the proximal knuckle slider body 171, and a spur gear 173 fixed on the second rotating shaft 52 and engaged with the rack 172, the bottom surface of the proximal knuckle slider body 171 is a rectangular plane 174 having the same width as that of the fingers, the proximal knuckle slider body 171 is provided with a second kidney-shaped notch 175 disposed in the vertical direction, the rack-and-pinion adaptive mechanism 17 further includes a first round-head pin 176 and a second round-head pin 177 vertically penetrating the third ear plate 123 and the fourth ear plate 124, the first round-head pin 176 and the second round-head pin 177 are respectively provided with a first micro bearing 178 and a second micro bearing 179, the first micro bearing 178 and the second micro bearing 175 are located in the second kidney-shaped notch, and the proximal knuckle slider body 171 can slide over the first and second micro-bearings 178 and 179 in the direction defined by the second kidney-shaped notch 175. When the proximal knuckle slider body 171 contacts an object, the proximal knuckle slider body 171 slides upward, causing the spur gear 173, the second rotating shaft 52, and the middle knuckle link 22 to rotate together, thereby causing the distal knuckle link 33 to rotate, i.e., to achieve passive adaptive motion. The first and

second micro bearings

178 and 179 function to reduce friction and allow the proximal knuckle slider body 171 to slide along the second kidney-shaped notch 175 relative to the proximal knuckle link 12.

Furthermore, the proximal knuckle housing 11 and the proximal knuckle connecting rod 12 are connected at two ends thereof through a first rotating shaft 51 and a second rotating shaft 52, respectively, the driving bevel gear 15, the base joint support 13 and the angle sensor 16 are coaxially arranged with the first rotating shaft 51, the spur gear 173 in the rack-and-pinion adaptive mechanism 17 is coaxially arranged with the second rotating shaft 52, one end of the connecting rod 14 forms a sliding fit with the base joint support 13, and the other end of the connecting rod 14 is fixed on the second rotating shaft 52.

Specifically, as shown in fig. 11, the first rotating shaft 51 includes a first shaft segment 511, a second shaft segment 512, a third shaft segment 513 and a fourth shaft segment 514, which are sequentially arranged and are integrated into a whole, wherein: the first shaft section 511 is matched with the first lug plate 121 and the first support plate 131, the second shaft section 512 is matched with the driving bevel gear 15 and the second support plate 132, the third shaft section 513 is matched with the angle sensor 16, the fourth shaft section 514 is matched with the near knuckle housing 11, the part of the second shaft section 512 matched with the driving bevel gear 15 and the third shaft section 513 are D-shaped shafts, shaft elastic check rings are arranged at the end parts of the first shaft section 511 and the fourth shaft section 514, and the first rotating shaft 51 is sequentially connected with the first lug plate 121, the first support plate 131, the driving bevel gear 15, the second lug plate 122, the second support plate 132, the angle sensor 16 and the near knuckle housing 11.

Specifically, as shown in fig. 12, the second rotating shaft 52 includes a fifth shaft 521, a sixth shaft 522 and a seventh shaft 523, which are sequentially arranged and are integrated, the fifth shaft 521 is matched with the third ear plate 123, the first rib 211 of the middle knuckle housing 21 and the spur gear 173, the sixth shaft 522 is matched with the fourth ear plate 124 and the middle knuckle connecting rod 22, and the seventh shaft 523 is matched with the connecting rod 14, the second rib 212 of the middle knuckle housing 21 and the near knuckle housing 11, wherein: the part of the fifth shaft section 521, which is matched with the first rib plate 211 and the spur gear 173 of the middle knuckle shell 21, is a D-shaped shaft, the part of the sixth shaft section 522, which is matched with the middle knuckle connecting rod 22, is a D-shaped shaft, the second rotating shaft 52 is sequentially connected with the third lug plate 123, the first rib plate 211 of the middle knuckle shell, the spur gear 173, the fourth lug plate 124, the middle knuckle connecting rod 22, the connecting rod 14, the second rib plate 212 of the middle knuckle shell and the near knuckle shell 11, and one end of the second rotating shaft 52, which is close to the near knuckle shell 11, is provided with an elastic shaft check ring.

Further, as shown in fig. 8, a cylindrical boss 143 for mounting the torsion spring 142 is provided on an end surface of the second rib 212 of the connecting rod 14 close to the middle knuckle housing, one end of the torsion spring 142 is fixed with a first locking groove 144 provided on the second rib 212, and the other end of the torsion spring 142 is fixed with a second locking groove 145 provided on the connecting rod 14; namely, the torsion spring 142 is installed on the column-shaped boss 143 at the left end of the connecting rod 14, and two movable ends of the torsion spring 142 are respectively fixed on the second clamping groove 145 on the connecting rod 14 and the first clamping groove 144 on the middle knuckle housing 21; the end surfaces of the connecting rod 14 close to the middle knuckle connecting rod 22 are respectively provided with 120-degree annular bosses 146, the axial installation positions of the two annular bosses 146 are staggered, in an initial state, the middle knuckle connecting rod 22 is attached to the connecting rod 14 in the axial direction, and the middle knuckle connecting rod 22 cannot rotate clockwise relative to the connecting rod 14 under the limit of the annular bosses 146. That is, the initial position of installation is that the middle knuckle connecting rod 22 cannot rotate clockwise relative to the connecting rod 14 around the second rotating shaft 52 due to the limiting effect of the annular boss 146, and the torsion spring 142 is used for axially fitting the connecting rod 14 and the middle knuckle connecting rod 22 together at the initial position and providing initial pre-tightening force, that is, in the initial position, the middle knuckle connecting rod 22 cannot rotate clockwise relative to the connecting rod 14, and when rotating counterclockwise, the resistance of the torsion spring 142 needs to be overcome.

Further, the middle finger assembly 2 includes a middle finger joint housing 21 and a middle finger joint connecting rod 22, two ends of the middle finger joint housing 21 are respectively connected through a second rotating shaft 52 and a first pin shaft 53, the middle finger joint housing 21 includes a first rib plate 211 and a second rib plate 212 which are arranged in parallel in the vertical direction, the bottoms of the first rib plate 211 and the second rib plate 212 are connected through a bottom plate 213,

further, the distal finger assembly 3 comprises a distal knuckle shell 31, a distal knuckle upper end cover 32 and a distal knuckle connecting rod 33, and the bottom of the distal knuckle shell 31 is provided with a film touch force sensor 4; the distal knuckle housing 31 includes a third rib 311 and a fourth rib 312 which are arranged in parallel, the front side and the bottom side of the third rib 311 and the fourth rib 312 surround a connecting plate 313, the distal knuckle upper end cap 32 includes a fifth rib 321 and a sixth rib 322 which are arranged in parallel, the upper plate surfaces of the fifth rib 321 and the sixth rib 322 are provided with a top plate 323 connecting the fifth rib 321 and the sixth rib 322, the fifth rib 321 and the sixth rib 322 are respectively located at the outer sides of the third rib 311 and the fourth rib 312, and the distal knuckle connecting rod 33 is arranged between the third rib 311 and the fourth rib 312.

Furthermore, the two ends of the distal knuckle housing 31 and the distal knuckle upper end cover 32 are connected by a first pin shaft 53 and a second pin shaft 54, respectively, one end of the middle knuckle connecting rod 22 is fixed on the second rotating shaft 52, the other end of the middle knuckle connecting rod 22 is fixed on the first pin shaft 53, one end of the distal knuckle connecting rod 33 is connected with the second pin shaft 54, the other end of the distal knuckle connecting rod 33 forms a sliding fit with the proximal knuckle connecting rod 12, and the middle of the distal knuckle connecting rod 33 is connected with the first pin shaft 53.

Further, the distal knuckle connecting rod 33 includes a horizontal rod 331 and an inclined rod 332 extending in a right-downward direction along an end of the horizontal rod 331, the horizontal rod 331 and the inclined rod 332 are of an integral structure, two ends of the horizontal rod 331 are respectively connected to the second pin 54 and the first pin 53, an end of the inclined rod 332 is provided with a second external thread cylindrical pin 34, the second external thread cylindrical pin 34 is provided with a second bearing 341, and the second bearing 341 and the third kidney-shaped notch 126 form a sliding fit. The middle knuckle connecting rod 22, the plate 134, the second bearing 341 and the diagonal rod 332 of the far knuckle connecting rod form a second set of slider link mechanisms, and when the middle knuckle connecting rod 22 rotates a certain angle, the far knuckle connecting rod 33 rotates a corresponding angle, namely, the kinematic coupling of the middle knuckle connecting rod 22 and the far knuckle connecting rod 33 is realized.

Further, as shown in fig. 14, the device further comprises a sensing system, the sensing system comprises a current sensor 6, an angle sensor 16 fixed on the first rotating shaft 51, and a film touch force sensor 4 adhered to the lower side of the distal knuckle housing 31, the sensing system is connected with the control board 7, and the control board 7 collects sensor signals to control the position and the moment of the dc servo motor 8.

Furthermore, the angle sensor 16 is an R24HS robot joint angle sensor, the central rotating shaft of the angle sensor is a hollow structure, the inner core rotor of the angle sensor is fixed on the first rotating shaft through a D-shaped shaft during installation, and the shell of the angle sensor is fixed on the base joint support; the film touch force sensor 4 is an FSR402 film pressure sensor, and the current sensor 6 is a WCS2801 current detection sensor, and is used for detecting the current of the direct current servo motor and controlling the motor torque.

As shown in fig. 6, the proximal knuckle connecting rod 12, the plate 134 of the base joint support 13, the first bearing and the connecting rod 14 form a first set of slider link mechanisms, the proximal knuckle connecting rod 12 and the connecting rod 14 are coupled in motion, and the rotation angles have an approximately linear relationship; the middle knuckle connecting rod 22, the extension plate of the near knuckle connecting rod 12, the second bearing and the inclined rod of the far knuckle connecting rod 33 form a second group of connecting rod sliding block mechanisms, the middle knuckle connecting rod 22 and the far knuckle connecting rod 33 are coupled in motion, and the rotation angle has an approximately linear relation; because the connecting rod 14 and the middle knuckle connecting rod 22 are limited due to relative rotation and are pre-tightened by the torsion spring 142, when the fingers move freely or the front ends of the fingers are stressed, the connecting rod 14 and the middle knuckle connecting rod 22 cannot rotate relatively, which is equivalent to a rod, namely the motion coupling of the near knuckle connecting rod 12, the middle knuckle connecting rod 22, the connecting rod 14 and the far knuckle connecting rod 33, so that the continuous coupling motion of the near knuckle, the middle knuckle and the far knuckle of the fingers is realized.

As shown in fig. 5, when the proximal knuckle slider body 171 in the proximal finger assembly 1 first contacts an object, the proximal knuckle slider body 171 is pressed to drive the rack 172 to move upward, so that the spur gear 173 rotates counterclockwise, and since the second rotating shaft 52, the spur gear 173, and the middle knuckle link 22 are fixed together, the middle knuckle link 22 continues to rotate downward, and the distal knuckle link 33 also moves downward in a coupling manner, the above-mentioned grabbing method is adaptive grabbing, and can adapt to objects of different shapes; in the self-adaptive gripping process, the connecting rod 14 and the middle knuckle connecting rod 22 rotate relatively, the torsion spring 142 compresses, the middle knuckle and the far knuckle are coupled in motion, the motions of the near knuckle and the middle knuckle are mutually independent, the near knuckle rotates in a small amplitude under the action of the direct current servo motor, and the middle knuckle rotates in a large amplitude due to the relative sliding of the near knuckle sliding block body 171 and the near knuckle connecting rod 12 until an object is gripped;

as shown in fig. 13, the dc servo motor drives the drive bevel gear 15 to rotate, so as to move the near knuckle connecting rod 12, and the motion is transmitted to the middle knuckle and the far knuckle through the sliding block connecting rod transmission mechanism or the gear rack self-adaptive structure;

the invention comprises two grabbing operation modes:

one is fingertip grasping. The method specifically comprises the following steps: recording related programs to an Arduino control board, sending an instruction to a direct current servo motor driving module to drive a direct current servo motor, wherein a small bevel gear is installed at the front end of the direct current servo motor to drive a driving bevel gear, a first rotating shaft and a near knuckle connecting rod to rotate together; the angle sensor is used for measuring the rotation angle of the proximal knuckle and controlling the position and the rotation speed of the direct current servo motor by matching with a Hall encoder on the direct current servo motor; when the fingertip contacts an object, the current sensor can measure the current passing through the motor, the current through the control motor can control the torque of the direct current servo motor, the film touch force sensor measures the contact force between the fingertip and the object, and the fingertip force is controlled through the signal feedback of the film touch force sensor.

Secondly, adaptive grabbing. The method specifically comprises the following steps: burning related programs to an Arduino control board, sending an instruction to a direct current servo motor driving module to drive a direct current servo motor, wherein a small bevel gear is installed at the front end of the direct current servo motor to drive a driving bevel gear, a first rotating shaft and a near knuckle connecting rod to rotate together, envelope grabbing is performed at the moment, a near knuckle sliding block body contacts an object firstly, the near knuckle sliding block body moves upwards relative to the near knuckle connecting rod, a rack drives a straight gear, a second rotating shaft and a middle knuckle connecting rod to rotate anticlockwise, a torsion spring is compressed, the middle knuckle connecting rod rotates relative to the connecting rod, the near knuckle of a dexterous finger basically does not rotate due to the blocking of the object, and the middle knuckle and a far knuckle continue to rotate until the object is grabbed; self-adaptive grabbing control can be realized by only controlling the torque of the direct current servo motor.

The above-mentioned embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solution of the present invention by those skilled in the art should fall within the protection scope defined by the claims of the present invention without departing from the spirit of the present invention.

Claims

1. The utility model provides a self-adaptation under actuated finger device based on connecting rod transmission which characterized in that: the finger-joint type finger-joint hand comprises a near finger component (1), a middle finger component (2) and a far finger component (3) which are sequentially arranged and hinged, wherein the near finger component (1) comprises a near finger-joint shell (11), a near finger-joint connecting rod (12), a base joint support (13) fixed on the palm of a dexterous hand, a connecting rod (14) connected with the base joint support (13) in a sliding manner, a driving bevel gear (15) connected with a direct-current servo motor, an angle sensor (16) and a gear rack self-adaption mechanism (17), the middle finger component (2) comprises a middle finger-joint shell (21) and a middle finger-joint connecting rod (22), the far finger component (3) comprises a far finger-joint shell (31), a far finger-joint upper end cover (32) and a far finger-joint connecting rod (33), and a thin film touch force sensor (4) is arranged at the bottom of the far finger-joint shell (31); the two ends of the near knuckle shell (11) and the near knuckle connecting rod (12) are respectively connected through a first rotating shaft (51) and a second rotating shaft (52), the drive bevel gear (15), the base joint support (13) and the angle sensor (16) are coaxially arranged with the first rotating shaft (51), a straight gear in the gear and rack self-adaptive mechanism (17) is coaxially arranged with the second rotating shaft (52), one end of the connecting rod (14) forms sliding fit with the base joint support (13), the other end of the connecting rod (14) is fixed on the second rotating shaft (52), the two ends of the middle knuckle shell (21) are respectively connected through the second rotating shaft (52) and a first pin shaft (53), the two ends of the far knuckle shell (31) and the far knuckle upper end cover (32) are respectively connected through the first pin shaft (53) and a second pin shaft (54), one end of the middle knuckle connecting rod (22) is fixed on the second rotating shaft (52), the other end of well knuckle connecting rod (22) is fixed on first round pin axle (53), the one end of far knuckle connecting rod (33) links to each other with second round pin axle (54), and the other end and the nearly knuckle connecting rod (12) of far knuckle connecting rod (33) form sliding fit, and the middle part of far knuckle connecting rod (33) links to each other with first round pin axle (53), rack and pinion self-adaptation mechanism (17) include nearly knuckle slider body (171), set up rack (172) on nearly knuckle slider body (171) and fix on second pivot (52) and with rack (172) matched with straight-teeth gear (173), the bottom surface of nearly knuckle slider body (171) is rectangle plane (174) with the finger width, sets up the second kidney-shaped notch (175) that vertical direction arranged on nearly knuckle slider body (171), rack and pinion self-adaptation mechanism (17) still arrange and perpendicularly run through the first circle (175) of third otic placode (123) and fourth otic placode (124) including being that the upper and lower direction was arranged and being The first round-head pin (176) and the second round-head pin (177), a first miniature bearing (178) and a second miniature bearing (179) are arranged on the first round-head pin (176) and the second round-head pin (177) respectively, the first miniature bearing (178) and the second miniature bearing (179) are located in the second kidney-shaped notch (175), and the near knuckle slider body (171) can slide on the first miniature bearing (178) and the second miniature bearing (179) along the direction limited by the second kidney-shaped notch (175).

2. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: the base joint support (13) comprises a first support plate (131) and a second support plate (132) which are parallel to the proximal knuckle connecting rod (12), a base (133) for connecting the first support plate (131) and the second support plate (132) is arranged at the bottom of the first support plate (131) and the second support plate (132), one end of the base (133) is flush with the end face of the first support plate (131), the length of the base (133) is larger than the distance between the first support plate (131) and the second support plate (132), the first support plate (131) is located between the driving bevel gear (15) and the first ear plate, the second support plate (132) is located between the second ear plate and the angle sensor (16), a plate body (134) connected with the connecting rod (14) extends leftwards from the second support plate (132), the plate body (134) and the second support plate (132) are of an integral structure, and a first cylindrical pin (18) is arranged at the end of the plate body (134), the first external thread cylindrical pin (18) is provided with a first bearing (181), one end of the connecting rod (14) is provided with a first kidney-shaped notch (141) matched with the first bearing (181), the first bearing (181) slides in the range limited by the first kidney-shaped notch (141), and the other end of the connecting rod (14) is hinged to the second rotating shaft (52).

3. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: the near knuckle shell (11) is arranged in parallel with the near knuckle connecting rod (12), and the driving bevel gear (15) is positioned between a first lug plate (121) and a second lug plate (122) formed at the right end of the near knuckle connecting rod (12); the gear and rack self-adaption mechanism (17) is arranged between a third lug plate (123) and a fourth lug plate (124) formed at the left end of the near knuckle connecting rod (12), a through groove (127) matched with the gear and rack self-adaption mechanism (17) in shape is formed between the third lug plate (123) and the fourth lug plate (124), an extension plate (125) in sliding fit with the far knuckle connecting rod (33) extends leftwards and downwards from the end part of the fourth lug plate (124), and a third kidney-shaped notch (126) is formed in the extension plate (125); the middle knuckle shell (21) comprises a first rib plate (211) and a second rib plate (212) which are arranged in parallel in the vertical direction, the bottoms of the first rib plate (211) and the second rib plate (212) are connected through a bottom plate (213), the far knuckle shell (31) comprises a third rib plate (311) and a fourth rib plate (312) which are arranged in parallel, the front sides and the bottom sides of the third ribbed plates (311) and the fourth ribbed plates (312) are surrounded by connecting plates (313), the distal knuckle upper end cover (32) comprises a fifth ribbed plate (321) and a sixth ribbed plate (322) which are arranged in parallel, the upper plate surfaces of the fifth ribbed plate (321) and the sixth ribbed plate (322) are provided with a top plate (323) for connecting the fifth ribbed plate and the sixth ribbed plate, the fifth rib (321) and the sixth rib (322) are respectively positioned at the outer sides of the third rib (311) and the fourth rib (312), the far knuckle connecting rod (33) is arranged between the third rib plate (311) and the fourth rib plate (312).

4. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: first pivot (51) including arrange in proper order and first shaft part (511), second shaft part (512), third shaft part (513) and fourth shaft part (514) as an organic whole structure, wherein: first shaft section (511) cooperatees with first otic placode (121) and first mounting plate (131), and second shaft section (512) cooperatees with drive bevel gear (15) and second mounting plate (132), and third shaft section (513) cooperatees with angle sensor (16), and fourth shaft section (514) cooperatees with nearly knuckle shell (11), second shaft section (512) and drive bevel gear (15) matched with position and third shaft section (513) be D type axle, the tip of first shaft section (511) and fourth shaft section (514) is equipped with axle and uses circlip, first pivot (51) connect gradually first otic placode (121), first mounting plate (131), drive bevel gear (15), second otic placode (122), second mounting plate (132), angle sensor (16) and nearly knuckle shell (11).

5. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: second pivot (52) including arrange in proper order and fifth axial segment (521), sixth axial segment (522) and seventh axial segment (523) as an organic whole structure, fifth axial segment (521) cooperate with first floor (211), spur gear (173) of third otic placode (123), well knuckle shell (21), sixth axial segment (522) cooperate with fourth otic placode (124) and well knuckle connecting rod (22), seventh axial segment (523) cooperate with second floor (212) and nearly knuckle shell (11) of connecting rod (14), well knuckle shell (21), wherein: fifth shaft section (521) is D type axle with first floor (211) and straight gear (173) matched with position of well knuckle shell (21), sixth shaft section (522) is D type axle with well knuckle connecting rod (22) matched with position, second pivot (52) connect gradually third otic placode (123), first floor (211) of well knuckle shell, straight gear (173), fourth otic placode (124), well knuckle connecting rod (22), connecting rod (14), second floor (212) and nearly knuckle shell (11) of well knuckle shell, and the one end that second pivot (52) are close to nearly knuckle shell (11) is equipped with the circlip for the axle.

6. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: a columnar boss (143) for mounting a torsion spring (142) is arranged on the end face of the second rib plate (212) of the connecting rod (14) close to the middle knuckle shell, one end of the torsion spring (142) is fixed with a first clamping groove (144) formed in the second rib plate (212), and the other end of the torsion spring (142) is fixed with a second clamping groove (145) formed in the connecting rod (14); the end faces, close to each other, of the connecting rod (14) and the middle knuckle connecting rod (22) are respectively provided with 120-degree annular bosses (146), the axial installation positions of the two annular bosses (146) are staggered, the middle knuckle connecting rod (22) and the connecting rod (14) are axially attached together in an initial state, and the middle knuckle connecting rod (22) cannot rotate clockwise relative to the connecting rod (14) under the limiting of the annular bosses (146).

7. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: the far knuckle connecting rod (33) comprises a horizontal rod (331) and an inclined rod (332) extending towards the right lower direction along the end portion of the horizontal rod (331), the horizontal rod (331) and the inclined rod (332) are of an integral structure, two ends of the horizontal rod (331) are respectively connected with a second pin shaft (54) and a first pin shaft (53), a second external thread cylindrical pin (34) is arranged at the end portion of the inclined rod (332), a second bearing (341) is arranged on the second external thread cylindrical pin (34), and the second bearing (341) and a third kidney-shaped notch (126) form sliding fit.

8. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 1, wherein: still include sensing system, sensing system include current sensor (6), fix angle sensor (16) on first pivot (51) and paste in the film touch force sensor (4) of far knuckle shell (31) downside, sensing system link to each other with control panel (7), control panel (7) gather sensor signal and are used for controlling the position and the moment of direct current servo motor (8).

9. The adaptive under-actuated finger device based on a connecting rod transmission as claimed in claim 8, wherein: the angle sensor (16) adopts an R24HS robot joint angle sensor, the central rotating shaft of the angle sensor is of a hollow structure, the film touch force sensor (4) is an FSR402 film pressure sensor, and the current sensor (6) is a WCS2801 current detection sensor.