A mechanical bionic hand

Abstract

The present invention proposes a mechanical bionic hand, comprising two first modular fingers, two first modular finger driving mechanisms, a second modular finger, and a second modular finger driving mechanism; the two first modular fingers are used to simulate the index finger and the middle finger, respectively, and the second modular finger is used to simulate the ring finger and the little finger. The finger anti-collision mechanism proposed in the present invention enhances the safety and stability of the fingers; the bionic hand adopts an under-actuated design, reduces the weight of the traditional bionic manipulator, gets rid of the bulky characteristics of the rigid manipulator, and brings a just right experience to the user.

Description

Technical Field

[0001] The invention belongs to the technical field of medical rehabilitation and relates to a bionic hand, in particular to a mechanical bionic hand. Background Art

[0002] Bionic hands are the main means to solve the problem of patients taking care of themselves after amputation. They are still a relatively new and popular product. There are varying types of products on the market, and there are no clear requirements and standards for such products in the industry.

[0003] Existing bionic hand products have rich design concepts. Flexible mechanisms and rigid mechanisms can be seen everywhere in the market, with obvious advantages and disadvantages. The service life of flexible mechanisms is limited, and the wear of driving ropes is the primary problem in the development and market expansion of such products. The bionic hands with rigid connecting rods as the motion mechanism have problems such as large mass, slow and insensitive movement, poor and inconvenient user experience, etc., which are also limitations encountered in the promotion of such products in the market.

[0004] In view of this, there is an urgent need to design a bionic hand structure to overcome the above-mentioned defects of the existing bionic hand structure. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a mechanical bionic hand that is light, convenient and has an excellent user experience: the bionic hand adopts an under-actuated design, which greatly reduces the weight of traditional bionic manipulators, gets rid of the bulky characteristics of rigid manipulators, and brings just the right experience to users.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A mechanical bionic hand, comprising two first modular fingers, two first modular finger driving mechanisms, a second modular finger, a second modular finger driving mechanism, a thumb mechanism, a thumb driving mechanism, and a thumb planetary gear transmission mechanism;

[0008] The first modular finger includes one modular finger, and the second modular finger includes two modular fingers; the two first modular fingers are used to simulate the index finger and the middle finger respectively, the second modular finger is used to simulate the ring finger and the little finger, and the thumb mechanism is used to simulate the thumb;

[0009] Each first modular finger driving mechanism is connected to the corresponding first modular finger to drive the first modular finger to move; the second modular finger driving mechanism is connected to the second modular finger to drive the second modular finger to move; the thumb driving mechanism is connected to the thumb mechanism through the thumb planetary gear transmission mechanism to drive the thumb mechanism to move;

[0010] The modular finger comprises a distal finger joint, a finger connecting rod, a proximal finger joint housing, a torsion spring, a finger linkage rod 15, and an anti-collision mechanism; the anti-collision mechanism comprises a finger tension anti-collision rod;

[0011] The distal knuckle of the finger, the finger connecting rod and the finger proximal knuckle housing are connected in pairs by 2mm bolts through interference fit to prevent axial displacement. The following 2mm bolt connection methods are all like this (i.e. connected by interference fit); the finger linkage rod and the finger proximal knuckle housing are connected by 2mm bolts; the finger linkage rod and the finger tension anti-collision rod are connected by 2mm bolts;

[0012] The front end of the finger tension anti-collision rod is connected to the finger linkage rod through a 2mm bolt; the rear end of the finger tension anti-collision rod is connected to the output shaft of the linear motor through a 2mm bolt;

[0013] The first modular finger driving mechanism includes a first linear motor; the second modular finger driving mechanism includes a second linear motor; the first linear motor and the second linear motor each include a linear motor body and a linear motor fixed end; each first linear motor can drive a corresponding modular finger movement, and the second linear motor is connected to two modular fingers included in the second modular finger, and can drive two modular fingers to move;

[0014] The linear motor body is connected to the finger tension anti-collision rod, the finger tension anti-collision rod is connected to one end of the finger linkage rod, the finger linkage rod is respectively connected to the finger connecting rod and the finger proximal knuckle housing with 2mm bolts, and one end of the finger connecting rod is rotatably connected to one end of the finger distal knuckle;

[0015] The finger linkage rod can drive the finger proximal knuckle housing and the finger connecting rod to perform circular motion under the drive of the linear motor body and the finger tension anti-collision rod. Since there is a speed difference between the circular motions of the two, the relative speed difference of the circular motion will cause the connecting rod with a faster circular speed to drive the finger distal knuckle to perform bending motion. If a bolt fixing point of the finger base knuckle is regarded as the absolute instantaneous center of velocity, the bending motion of the finger can be regarded as a circular motion around the instantaneous center. The finger connecting rod and the finger proximal knuckle housing have different radii from the first and second fixing points of the finger distal knuckle, respectively, so there is a speed difference in the circular motion under the same angular velocity.

[0016] The finger is restored by adding a torsion spring and a preload is added to keep the finger in a natural state. The torsion spring is embedded in the connection point between the proximal knuckle shell and the distal knuckle of the finger. One end of the torsion spring is embedded in the distal knuckle of the finger, and the other end is embedded in the groove of the finger connecting rod. When the finger is bent, an opposite torque is applied to the finger so that the finger returns to the extended state without the motor doing work.

[0017] When external force bends the finger, an anti-collision mechanism is added to prevent excessive external force from being transmitted from the knuckle to the motor push rod through the finger; when external force acts on the finger, the bending of the finger drives the finger connecting rod to move downward, and then the finger tension anti-collision rod continues to move downward through the linkage rod. However, since the tension anti-collision rod is provided with a slide groove on the upper part, it can only provide tension but not thrust within a limited range. In this way, the external force cannot act on the motor push rod, causing damage to the motor; when the motor works normally, the motor provides tension, which drives the finger tension anti-collision rod to move downward through the pull rod, thereby driving the bending of the finger mechanism;

[0018] The thumb mechanism includes a distal thumb joint, a distal thumb joint, a middle portion of a thumb rotating motor base, a side plate of a thumb rotating motor base, a proximal thumb joint housing, a motor fixing belt, a first bevel gear, and a transmission sheet;

[0019] The thumb planetary gear rotating mechanism includes a second bevel gear, a third bevel gear, a first bearing, a second bearing, a planetary gear of a planetary gear mechanism, a variable diameter shaft, a rotating sheet, an axial fixing member, a sun gear of a planetary gear mechanism, and an axial fixing member;

[0020] The thumb drive mechanism includes a micro reduction motor; the micro reduction motor is fixed to the middle part of the thumb base through a motor fixing belt, one end of the micro reduction motor is connected to a first bevel gear, and the first bevel gear is meshed with a second bevel gear 55; the bevel gear is installed on the first D-shaped shaft and fits together with the transmission sheet; the rotation of the bevel gear can drive the first D-shaped shaft to rotate, and then drive the transmission sheet to rotate;

[0021] The transmission sheet is arranged close to the outer shell of the proximal knuckle of the thumb, and the rotation of the transmission sheet can push the outer shell of the proximal knuckle of the thumb, thereby pushing the rotation of the distal joint of the thumb, and driving the distal knuckle of the thumb connected to the distal joint of the thumb to rotate;

[0022] The second bevel gear is meshed with the third bevel gear to drive the third bevel gear to rotate, and the third bevel gear is installed on the second D-shaped shaft, and then drives the planetary gear to rotate through the second D-shaped shaft. The first bearing and the second bearing are respectively provided on both sides of the gear to enhance the stability of its movement and limit its axial displacement. The second D-shaped shaft is designed to be a variable diameter type, so the axial displacement of one end thereof is limited, and the other end is limited by the axial fixing member 54 to limit its displacement; the planetary gear is meshed with the sun gear fixed on the palm. Different from the planetary gear, the third D-shaped shaft of the sun gear is designed to be non-rotatable, and the shaft hole of its mounting base is also D-shaped, while the shaft hole of the mounting base of the planetary gear is circular; therefore, the sun gear does not move, and moves in a circle around the sun gear under the restriction of the rotating sheet;

[0023] The bending movement and rotation movement of the thumb finger are coupled, and the degree of bending is in a set proportion to the rotation angle. When the micro reduction motor rotates, the bending direction of the thumb and the rotation direction of the thumb are both the same positive process or the same negative process. Here, the natural extension of the thumb is used as the initial state of the bending movement, and the thumb is placed on the side of the hand as the initial state of the thumb rotation movement. The process from the extension movement to the complete bending of the thumb is used as the positive direction, and the process from the side of the hand to perpendicular to the hand is used as the positive process of the rotation movement.

[0024] A mechanical bionic hand, comprising a mechanical hand part, the mechanical hand part comprising a palm mechanism, at least one modular finger, and at least one modular finger driving mechanism;

[0025] The modular finger driving mechanism is arranged in the palm mechanism, the palm mechanism is connected to each modular finger, and each modular finger driving mechanism is connected to the corresponding modular finger;

[0026] The modular finger includes a first finger joint, a finger connecting rod, a second finger joint, a reset mechanism, a finger linkage rod 15, and an anti-collision mechanism; the anti-collision mechanism includes a tension anti-collision rod;

[0027] The first finger joint is connected to the second finger joint through a finger connecting rod, and the first finger joint is connected to the second finger joint through a reset mechanism; the finger connecting rod and the second finger joint are respectively connected to the finger linkage rod;

[0028] The modular finger driving mechanism is connected to the tension anti-collision rod, and drives the corresponding modular finger to bend by driving the tension anti-collision rod; when the modular finger driving mechanism does not provide power or the power is reduced, the first knuckle and the second knuckle of the modular finger are reset or partially reset by the reset mechanism.

[0029] Furthermore, when external force acts on the finger, the finger bends and drives the finger connecting rod to move downward, and then the tension anti-collision rod continues to move downward through the finger linkage rod. However, since the tension anti-collision rod is provided with a slide groove on the upper part, when external force acts, the motor pull rod will move upward along the slide groove, so it can only provide thrust within the limited range and cannot act on the motor body. Therefore, the device can only provide tension but not thrust within the limited range. In this way, the external force cannot directly act on the motor pull rod and cause damage to the motor; when the motor works normally, the motor provides tension, which drives the finger tension anti-collision rod to move downward through the pull rod, thereby driving the bending of the finger mechanism.

[0030] The invention discloses a mechanical bionic hand, wherein underactuation means that the number of independent actuators in the system is less than the number of degrees of freedom. The bionic hand mainly consists of three parts: a motor, a wrist and a mechanical hand.

[0031] The manipulator consists of two modular fingers A, an anti-collision mechanism, a linear motor, a thumb mechanism, a thumb planetary gear rotation mechanism and one modular finger B.

[0032] The modular finger consists of a distal finger joint, a finger connecting rod, a proximal finger joint housing, a torsion spring, a finger linkage rod, a finger tension anti-collision rod, a linear motor, a modular housing cover, and a modular housing chassis.

[0033] The anti-collision mechanism is composed of a finger tension anti-collision rod, a linear motor, a finger linkage rod, a modular housing chassis, and a modular housing cover.

[0034] The linear motor is composed of a linear motor and a linear motor fixed end;

[0035] Modular finger structure of the bionic hand of the present invention:

[0036] Specifically: the finger tension anti-collision rod is driven by a linear motor and further drives the finger proximal knuckle shell and the finger connecting rod to perform circular motion through the finger linkage rod. Due to the speed difference between the two circular motions, the relative difference in the speed of the circular motion will cause the connecting rod with a faster circular speed to drive the finger distal knuckle to perform bending motion.

[0037] Furthermore, a torsion spring is added to restore the finger, and a preload is added to keep the finger in a natural state;

[0038] Furthermore, when external force bends the finger, in order to prevent excessive external force from being transmitted to the motor push rod through the finger, an anti-collision mechanism is added. Specifically: when external force acts on the finger, the bending of the finger drives the finger connecting rod to move downward, and then the finger tension anti-collision rod continues to move downward through the linkage rod. However, since the tension anti-collision rod has a sliding groove on the upper part, it can only provide tension but not thrust within a limited range. In this way, the external force cannot act on the motor push rod to damage the motor.

[0039] The beneficial effects of the mechanical bionic hand proposed by the present invention are:

[0040] 1. Long service life: It continues the durable characteristics of the rigid structure, ensuring the normal operation of the product for a long period of time;

[0041] 2. High reliability: The innovative anti-collision structure design is adopted, so that the motor and other driving structures will not be damaged when the mechanism is forced to move under the action of external force;

[0042] 3. Simple and elegant appearance: The anti-collision mechanism, linear motor and other devices are placed inside the palm, making the bionic hand simple and elegant in appearance, and the daily use of the product will not affect the precision parts from the outside;

[0043] 4. Lightweight and convenient, excellent experience: The bionic hand adopts an under-actuated design, which greatly reduces the weight of traditional bionic manipulators, gets rid of the bulky characteristics of rigid manipulators, and brings users just the right experience; BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic cross-sectional structural diagram of a mechanical bionic hand according to an embodiment of the present invention;

[0045] Figure 2 This is a front view of the mechanical bionic hand according to an embodiment of the present invention;

[0046] Figure 3 This is a schematic structural diagram of the thumb portion of the mechanical bionic hand of the present invention;

[0047] Figure 4 Another structural schematic diagram of the thumb part of the mechanical bionic hand of the present invention;

[0048] Figure 5 It is a schematic cross-sectional structure diagram of a modular finger 1 of a bionic hand according to an embodiment of the present invention;

[0049] Figure 6 A top view of a modular finger 1 of a bionic hand according to an embodiment of the present invention;

[0050] Figure 7 It is a front view of the modular finger 2 of the bionic hand according to an embodiment of the present invention.

[0051] Figure 8 It is a cross-sectional view of a modular finger 2 of a bionic hand according to an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Example

[0053] See also Figures 1 to 8 The present invention discloses a mechanical bionic hand, which may be an underactuated mechanical bionic hand, where underactuation means that the number of independent actuators in the system is less than the number of degrees of freedom. The mechanical bionic hand includes a wrist and a manipulator part; the manipulator part includes two first modular fingers, two first modular finger drive mechanisms, a second modular finger, a second modular finger drive mechanism, a thumb mechanism, and a thumb planetary gear transmission mechanism.

[0054] The first modular finger 1 includes one modular finger, and the second modular finger includes two modular fingers; the two first modular fingers are used to bionic the index finger and the middle finger respectively, the second modular finger is used to bionic the ring finger and the little finger, and the thumb mechanism is used to bionic the thumb.

[0055] Each first modular finger driving mechanism is connected to the corresponding first modular finger to drive the first modular finger to move; the second modular finger driving mechanism is connected to the second modular finger to drive the second modular finger to move; the thumb driving mechanism is connected to the thumb mechanism 4 through the thumb planetary gear transmission mechanism 5 to drive the thumb mechanism 4 to move;

[0056] The modular finger includes a distal finger joint 11 , a finger connecting rod 12 , a proximal finger joint housing 13 , a torsion spring 14 , a finger linkage rod 15 , and an anti-collision mechanism 2 ; the anti-collision mechanism 2 includes a finger tension anti-collision rod 21 .

[0057] The distal finger joint 11, the finger connecting rod 12 and the finger proximal finger joint housing 13 are connected in pairs by 2mm bolts through interference fit to prevent axial displacement. The following 2mm bolt connection methods are all the same; the finger linkage rod 15 is connected to the finger proximal finger joint housing 13 by 2mm bolts; the finger linkage rod 15 is connected to the finger tension anti-collision rod 21 by 2mm bolts;

[0058] The front end of the finger tension anti-collision rod 21 is connected to the finger linkage rod 15 through a 2mm bolt; the rear end of the finger tension anti-collision rod 21 is connected to the output shaft of the linear motor 3 through a 2mm bolt.

[0059] The first modular finger driving mechanism includes a first linear motor 3; the second modular finger driving mechanism includes a second linear motor; the first linear motor 3 and the second linear motor both include a linear motor body and a linear motor fixed end; each first linear motor 3 can drive a corresponding modular finger movement, and the second linear motor connects the two modular fingers included in the second modular finger and can drive the two modular fingers to move.

[0060] The linear motor body 22 is connected to the finger tension anti-collision rod 21, the finger tension anti-collision rod 21 is connected to one end of the finger linkage rod 15, the finger linkage rod 15 is respectively connected to the finger connecting rod 12 and the finger proximal knuckle shell 13 using 2mm bolts, and one end of the finger connecting rod 12 is rotatably connected to one end of the finger distal knuckle 11.

[0061] The finger linkage rod 15 can drive the finger proximal knuckle shell 13 and the finger connecting rod 12 to perform circular motion under the drive of the linear motor body 22 and the finger tension anti-collision rod 21. Since there is a speed difference in the circular motion of the two, the relative speed difference of the circular motion will cause the connecting rod 12 with a faster circular speed to drive the finger distal knuckle 11 to perform bending motion; if a bolt fixing point of the finger base knuckle is regarded as the absolute instantaneous center of velocity, the bending motion of the finger can be regarded as a circular motion around the instantaneous center, and the finger connecting rod 12 and the finger proximal knuckle shell 13 have different radii from the absolute instantaneous center from the first fixed point and the second fixed point of the finger distal knuckle 11, respectively, so there is a speed difference in the circular motion under the same angular velocity.

[0062] The finger is restored by adding a torsion spring 14, and a pre-tightening force is added to keep the finger in a natural state; the torsion spring 14 is embedded in the connection point between the proximal knuckle shell 13 of the finger and the distal knuckle 11 of the finger, one end of the torsion spring is embedded in the distal knuckle 11 of the finger, and the other end is embedded in the groove of the finger connecting rod 12. When the finger is bent, an opposite torque is applied to the finger so that the finger returns to the extended state without the motor doing work.

[0063] When external force bends the finger, an anti-collision mechanism is added to prevent excessive external force from being transmitted to the motor's push rod through the finger knuckles; when external force acts on the finger, the bending of the finger drives the finger connecting rod 12 to move downward, and then the finger tension anti-collision rod 21 continues to move downward through the linkage rod 15. However, since the tension anti-collision rod 21 is provided with a slide groove on the upper part, it can only provide tension but not thrust within a limited range. In this way, the external force cannot act on the motor push rod and cause damage to the motor; when the motor works normally, the motor provides tension, which drives the finger tension anti-collision rod 21 to move downward through the pull rod, thereby driving the bending of the finger mechanism.

[0064] The thumb mechanism 4 includes a thumb distal knuckle 41 , a thumb distal joint 42 , a thumb rotating motor base middle portion 43 , a thumb rotating motor base side plate 44 , a thumb proximal knuckle housing 45 , a motor fixing belt 47 , a first bevel gear 48 , and a transmission sheet 49 .

[0065] The thumb mechanism 4 includes a differential coupling mechanism, which is a mechanism for bending the thumb, and refers to most of the parts of the thumb mechanism 4 except the distal thumb joint 41 and the fixing belt 47, including the distal thumb joint 42, the middle part of the thumb rotating motor base 43, the proximal thumb joint housing 45, the thumb rotating motor 46, the first bevel gear 48, and the transmission plate 49.

[0066] The thumb drive unit is fixed to the middle part 43 of the thumb base through the motor fixing belt 47. One end of the thumb drive unit 46 is connected to the first bevel gear 48, which is meshed with the second bevel gear 55. The bevel gear 55 is installed on the first D-shaped shaft and fits with the transmission plate 49. The rotation of the bevel gear 55 can drive the first D-shaped shaft to rotate, and then drive the transmission plate 49 to rotate. The transmission plate 49 is arranged close to the thumb proximal knuckle shell 45. The rotation of the transmission plate 49 can push the thumb proximal knuckle shell 45, thereby pushing the rotation of the thumb distal joint 42, and driving the thumb distal knuckle 41 connected to the thumb distal joint 42 to rotate.

[0067] The differential coupling mechanism is based on the middle part 43 of the stationary thumb rotating motor base, and the thumb driving unit drives the first bevel gear 48, and then the first bevel gear 48 is engaged with the second bevel gear 51, driving the transmission plate 49 fixedly connected to the second bevel gear 51, thereby driving the thumb proximal knuckle shell 45 to push the joint 42 forward, thereby bending the finger.

[0068] The thumb planetary gear rotating mechanism 5 (as the thumb overall rotation transmission mechanism) includes a second bevel gear 51, a third bevel gear 52, a first bearing 53, a second bearing 54, a planetary gear 55 of a planetary gear mechanism, a variable diameter shaft 56, a rotating sheet 57, an axial fixing member 58, a sun gear 59 of a planetary gear mechanism, and an axial fixing member 510.

[0069] The thumb drive mechanism includes a micro reduction motor 46. The micro reduction motor 46 is fixed to the middle part 43 of the thumb base through a motor fixing belt 47. One end of the micro reduction motor 46 is connected to a first bevel gear 48, and the first bevel gear 48 is meshed with a second bevel gear 51; the second bevel gear 51 is installed on the first D-shaped shaft and fits together with the transmission plate; the rotation of the second bevel gear 51 can drive the first D-shaped shaft to rotate, and then drive the transmission plate 49 to rotate.

[0070] The transmission plate 49 is arranged close to the thumb proximal knuckle shell 45. The rotation of the transmission plate 49 can push the thumb proximal knuckle shell 45, thereby pushing the rotation of the thumb distal joint 42, and driving the thumb distal knuckle 41 connected to the thumb distal joint 42 to rotate.

[0071] The second bevel gear 51 is meshed with the third bevel gear 52 to drive the third bevel gear 52 to rotate, and the third bevel gear 52 is installed on the second D-shaped shaft, and then drives the planetary gear 55 to rotate through the second D-shaped shaft. A first bearing 53 and a second bearing 54 are respectively provided on both sides of the gear to enhance the stability of its movement and limit its axial displacement. The second D-shaped shaft is designed to be a variable diameter type, so the axial displacement of one end is limited, and the other end is limited by the axial fixing piece 510. The planetary gear 55 is meshed with the sun gear 59 fixed on the palm. Different from the planetary gear, the third D-shaped shaft of the sun gear is designed to be non-rotatable, and the axial hole of its mounting base is also D-shaped, while the axial hole of the mounting base of the planetary gear is circular; therefore, the sun gear 59 is stationary, and under the restriction of the rotating plate 57, it makes a circular motion around the sun gear 59.

[0072] The bending movement and rotation movement of the thumb finger are coupled, and the degree of bending is in a set proportion to the rotation angle. When the micro reduction motor rotates, the bending direction of the thumb and the rotation direction of the thumb are both the same positive process or the same negative process. Here, the natural extension of the thumb is used as the initial state of the bending movement, and the thumb is placed on the side of the hand as the initial state of the thumb rotation movement. The process from the extension movement to the complete bending of the thumb is used as the positive direction, and the process from the side of the hand to perpendicular to the hand is used as the positive process of the rotation movement.

[0073] The present invention uses the bending and rotation of the thumb as a linkage motion, abandoning the measuring and pinching motion. This linkage mode is sufficient to complete spherical grasping, columnar grasping and precise grasping, and only uses one motor, which reduces costs and can meet most daily needs. Example

[0074] An underactuated mechanical bionic hand comprises a mechanical hand part, wherein the mechanical hand part comprises a palm mechanism, at least one modular finger, and at least one modular finger driving mechanism (a thumb module may not be included, or the thumb structure is different from that in the first embodiment).

[0075] The modular finger driving mechanism is arranged in the palm mechanism, the palm mechanism is connected to each modular finger, and each modular finger driving mechanism is connected to the corresponding modular finger.

[0076] The modular finger comprises a first finger joint, a finger connecting rod, a second finger joint, a reset mechanism, a finger linkage rod, and an anti-collision mechanism; the anti-collision mechanism comprises a tension anti-collision rod.

[0077] The first finger joint is connected to the second finger joint through a finger connecting rod, and the first finger joint is connected to the second finger joint through a reset mechanism; the finger connecting rod and the second finger joint are respectively connected to the finger linkage rod.

[0078] The modular finger driving mechanism is connected to the tension anti-collision rod, and drives the corresponding modular finger to bend by driving the tension anti-collision rod; when the modular finger driving mechanism does not provide power or the power is reduced, the first knuckle and the second knuckle of the modular finger are reset or partially reset by the reset mechanism.

[0079] In summary, the underactuated mechanical bionic hand proposed by the present invention has the following advantages:

[0080] 1. Long service life: It continues the durable characteristics of the rigid structure, ensuring the normal operation of the product for a long period of time;

[0081] 2. High reliability: The innovative anti-collision structure design is adopted, so that the motor and other driving structures will not be damaged when the mechanism is forced to move under the action of external force;

[0082] 3. Simple and elegant appearance: The anti-collision mechanism, linear motor and other devices are placed inside the palm, making the bionic hand simple and elegant in appearance, and the daily use of the product will not affect the precision parts from the outside;

[0083] 4. Lightweight and convenient, excellent experience: The bionic hand adopts an under-actuated design, which greatly reduces the weight of traditional bionic manipulators, gets rid of the bulky characteristics of rigid manipulators, and brings users just the right experience;

[0084] 5. The thumb design adopts a differential coupling mechanism and a planetary gear mechanism, so that it can use a motor to control the rotation and bending of the thumb. While satisfying the requirement of a more compact structure, it does not give up the active rotation function of the thumb, instead of adopting a passive rotation structure. The designed working mode covers most of the needs of daily life.

[0085] The description and application of the present invention here are illustrative and are not intended to limit the scope of the present invention to the above-described embodiments. The deformation and changes of the embodiments disclosed here are possible, and the replacement of the embodiments and the various components equivalent to those of ordinary skill in the art are well known. It should be clear to those skilled in the art that the present invention can be realized in other forms, structures, arrangements, proportions, and with other components, materials and parts without departing from the spirit or essential characteristics of the present invention. Other deformations and changes can be made to the embodiments disclosed here without departing from the scope and spirit of the present invention.

Claims

1. A mechanical bionic hand, characterized in that: It includes two first modular fingers, two first modular finger driving mechanisms, a second modular finger, a second modular finger driving mechanism, a thumb mechanism, a thumb driving mechanism, and a thumb planetary gear transmission mechanism; The first modular finger (1) comprises a modular finger, and the second modular finger comprises two modular fingers; the two first modular fingers are used to simulate the index finger and the middle finger respectively, the second modular finger is used to simulate the ring finger and the little finger, and the thumb mechanism is used to simulate the thumb; Each first modular finger driving mechanism is connected to a corresponding first modular finger to drive the first modular finger to move; the second modular finger driving mechanism is connected to the second modular finger to drive the second modular finger to move; the thumb driving mechanism is connected to the thumb mechanism (4) via a thumb planetary gear transmission mechanism (5) to drive the thumb mechanism (4) to move; The modular finger comprises a distal finger joint (11), a finger connecting rod (12), a proximal finger joint housing (13), a torsion spring (14), a finger linkage rod (15), and an anti-collision mechanism (2); the anti-collision mechanism (2) comprises a finger tension anti-collision rod (21); The finger distal knuckle (11), the finger connecting rod (12) and the finger proximal knuckle housing (13) are connected in pairs by 2mm bolts through interference fit to prevent axial displacement. The following 2mm bolt connection methods are all connected in this way; the finger linkage rod (15) and the finger proximal knuckle housing (13) are connected by 2mm bolts; the finger linkage rod (15) and the finger tension anti-collision rod (21) are connected by 2mm bolts; The front end of the finger tension anti-collision rod (21) is connected to the finger linkage rod (15) via a 2mm bolt; the rear end of the finger tension anti-collision rod (21) is connected to the output shaft of the first linear motor (3) via a 2mm bolt; The first modular finger driving mechanism comprises a first linear motor (3); the second modular finger driving mechanism comprises a second linear motor; the first linear motor (3) and the second linear motor both comprise a linear motor body and a linear motor fixed end; each first linear motor (3) can drive a corresponding modular finger movement, and the second linear motor is connected to two modular fingers included in the second modular finger and can drive the two modular fingers to move; The linear motor body (22) is connected to the finger tension anti-collision rod (21), the finger tension anti-collision rod (21) is connected to one end of the finger linkage rod (15), the finger linkage rod (15) is respectively connected to the finger connecting rod (12) and the finger proximal knuckle housing (13) using 2mm bolts, and one end of the finger connecting rod (12) is rotatably connected to one end of the finger distal knuckle (11); The finger linkage rod (15) can drive the finger proximal knuckle housing (13) and the finger connecting rod (12) to perform circular motion under the drive of the linear motor body (22) and the finger tension anti-collision rod (21). Since there is a speed difference between the circular motions of the two, the relative speed difference of the circular motion will cause the finger connecting rod (12) with a faster circular speed to drive the finger distal knuckle (11) to perform bending motion. If a bolt fixing point of the finger base knuckle is regarded as the absolute instantaneous center of velocity, the bending motion of the finger can be regarded as a circular motion around the instantaneous center. The finger connecting rod (12) and the finger proximal knuckle housing (13) have different radii from the absolute instantaneous center to the first fixing point and the second fixing point of the finger distal knuckle (11), respectively. Therefore, under the same angular velocity, there is a speed difference in the circular motion. The finger is restored by adding a torsion spring (14) and a pre-tightening force is added so that the finger can be kept in a natural state; the torsion spring (14) is embedded in the connection point between the finger proximal knuckle shell (13) and the finger distal knuckle (11), one end of the torsion spring is embedded in the finger distal knuckle (11), and the other end is embedded in the groove of the finger connecting rod (12). When the finger is bent, an opposite torque is applied to the finger so that the finger is restored to the extended state without the motor doing work; When an external force bends the finger, an anti-collision mechanism is added to prevent excessive external force from being transmitted from the knuckle to the push rod of the motor through the finger; when an external force acts on the finger, the bending of the finger drives the finger connecting rod (12) to move downward, and then the finger tension anti-collision rod (21) continues to move downward through the finger linkage rod (15). However, since the finger tension anti-collision rod (21) is provided with a slide groove on the upper part, it can only provide tension but not thrust within a limited range. In this way, the external force cannot act on the motor push rod, causing damage to the motor; when the motor works normally, the motor provides tension, which drives the finger tension anti-collision rod (21) to move downward through the pull rod, thereby driving the bending of the finger mechanism; The thumb mechanism (4) comprises a thumb distal knuckle (41), a thumb distal joint (42), a middle portion of a thumb rotating motor base (43), a thumb rotating motor base side plate (44), a thumb proximal knuckle housing (45), a motor fixing belt (47), a first bevel gear (48), and a transmission sheet (49); The thumb planetary gear transmission mechanism (5) comprises a second bevel gear (51), a third bevel gear (52), a first bearing (53), a second bearing (54), a planetary gear (55) of a planetary gear mechanism, a variable diameter shaft (56), a rotating sheet (57), a first axial fixing member (58), a sun gear (59) of a planetary gear mechanism, and a second axial fixing member (510); The thumb drive mechanism comprises a micro reduction motor (46); the micro reduction motor (46) is fixed to the middle part (43) of the thumb rotating motor base through a motor fixing belt (47); one end of the micro reduction motor (46) is connected to a first bevel gear (48), and the first bevel gear (48) is meshed with a second bevel gear (51); the second bevel gear (51) is installed on the first D-shaped shaft and is fitted together with the transmission plate; the rotation of the second bevel gear (51) can drive the first D-shaped shaft to rotate, thereby driving the transmission plate (49) to rotate; The transmission plate (49) is arranged close to the thumb proximal knuckle housing (45), and the rotation of the transmission plate (49) can push the thumb proximal knuckle housing (45), thereby pushing the thumb distal joint (42) to rotate, and driving the thumb distal knuckle (41) connected to the thumb distal joint (42) to rotate; The second bevel gear (51) is meshed with the third bevel gear (52) to drive the third bevel gear (52) to rotate, and the third bevel gear (52) is installed on the second D-shaped shaft, and then drives the planetary gear (55) to rotate through the second D-shaped shaft. A first bearing (53) and a second bearing (54) are respectively provided on both sides of the gear to enhance the stability of its movement and limit its axial displacement. The second D-shaped shaft is designed to be a variable diameter type, so the axial displacement of one end thereof is limited, while the displacement of the other end is limited by the first axial fixing member (58); the planetary gear (55) is meshed with the sun gear (59) fixed on the palm. Different from the planetary gear, the third D-shaped shaft of the sun gear is designed to be non-rotatable, and the shaft hole of its mounting base is also D-shaped, while the shaft hole of the mounting base of the planetary gear is circular; therefore, the sun gear (59) is stationary, and moves in a circle around the sun gear (59) under the restriction of the rotating plate (57); The bending movement and rotation movement of the thumb mechanism are linked, and the degree of bending is in a set proportion to the rotation angle, and when the micro reduction motor rotates, the bending direction of the thumb mechanism and the rotation direction of the thumb are both the same positive process or the same negative process; here, the natural extension of the thumb mechanism is used as the initial state of the bending movement, the thumb mechanism is placed on the side of the hand as the initial state of the thumb rotation movement, the process of the thumb mechanism from extension movement to complete bending is used as the positive direction, and the process of the thumb mechanism moving from the side of the hand to perpendicular to the hand is used as the positive process of the rotation movement.

2. A mechanical bionic hand, characterized in that: The mechanical bionic hand comprises a mechanical hand part, which comprises a palm mechanism, at least one modular finger, and at least one modular finger driving mechanism; The modular finger driving mechanism is arranged in the palm mechanism, the palm mechanism is connected to each modular finger, and each modular finger driving mechanism is connected to the corresponding modular finger; The modular finger comprises a first finger joint, a finger connecting rod (12), a second finger joint, a reset mechanism, a finger linkage rod (15), and an anti-collision mechanism; the anti-collision mechanism comprises a finger tension anti-collision rod (21); The first finger joint is connected to the second finger joint via a finger connecting rod (12), and the first finger joint is connected to the second finger joint via a reset mechanism; the finger connecting rod (12) and the second finger joint are respectively connected to a finger linkage rod (15); The modular finger driving mechanism is connected to the finger tension anti-collision rod (21), and drives the corresponding modular finger to bend by driving the finger tension anti-collision rod (21); when the modular finger driving mechanism does not provide power or the power is reduced, the first knuckle and the second knuckle of the modular finger are reset or partially reset by the reset mechanism; When external force acts on the finger, the finger bends and drives the finger connecting rod (12) to move downward, and then the finger tension anti-collision rod (21) continues to move downward through the finger linkage rod (15). However, since the finger tension anti-collision rod (21) is provided with a slide groove on the upper part, when external force acts, the motor pull rod will move upward along the slide groove, so it can only provide thrust within a limited range and cannot act on the motor body. Therefore, the finger tension anti-collision rod (21) can only provide tension but not thrust within a limited range. In this way, the external force cannot directly act on the motor pull rod, causing the motor to be damaged; when the motor works normally, the motor provides tension, which drives the finger tension anti-collision rod (21) to move downward through the pull rod, thereby driving the bending of the finger mechanism.

3. The mechanical bionic hand according to claim 2, characterized in that: The manipulator part includes two first modular fingers, two first modular finger driving mechanisms, a second modular finger, a second modular finger driving mechanism, a thumb mechanism, and a thumb planetary gear transmission mechanism; The first modular finger (1) comprises a modular finger, and the second modular finger comprises two modular fingers; the two first modular fingers are used to simulate the index finger and the middle finger respectively, the second modular finger is used to simulate the ring finger and the little finger, and the thumb mechanism is used to simulate the thumb; Each first modular finger driving mechanism is connected to a corresponding first modular finger to drive the first modular finger to move; the second modular finger driving mechanism is connected to the second modular finger to drive the second modular finger to move; the thumb driving mechanism is connected to the thumb mechanism (4) via a thumb planetary gear transmission mechanism (5) to drive the thumb mechanism (4) to move.

4. The mechanical bionic hand according to claim 3, characterized in that: The first finger joint is a distal finger joint (11), and the second finger joint includes a proximal finger joint shell (13); The finger distal knuckle (11), the finger connecting rod (12) and the finger proximal knuckle housing (13) are connected in pairs by 2mm bolts through interference fit to prevent axial displacement. The following 2mm bolt connection methods are all connected in this way; the finger linkage rod (15) and the finger proximal knuckle housing (13) are connected by 2mm bolts; the finger linkage rod (15) and the finger tension anti-collision rod (21) are connected by 2mm bolts; The front end of the finger tension anti-collision rod (21) is connected to the finger linkage rod (15) via a 2mm bolt; the rear end of the finger tension anti-collision rod (21) is connected to the output shaft of the first linear motor (3) via a 2mm bolt; The first modular finger driving mechanism comprises a first linear motor (3); the second modular finger driving mechanism comprises a second linear motor; the first linear motor (3) and the second linear motor both comprise a linear motor body and a linear motor fixed end; each first linear motor (3) can drive a corresponding modular finger movement, and the second linear motor is connected to two modular fingers included in the second modular finger and can drive the two modular fingers to move; The linear motor body (22) is connected to the finger tension anti-collision rod (21), the finger tension anti-collision rod (21) is connected to one end of the finger linkage rod (15), the finger linkage rod (15) is respectively connected to the finger connecting rod (12) and the finger proximal knuckle housing (13) using 2mm bolts, and one end of the finger connecting rod (12) is rotatably connected to one end of the finger distal knuckle (11); The finger linkage rod (15) can drive the finger proximal knuckle housing (13) and the finger connecting rod (12) to perform circular motion under the drive of the linear motor body (22) and the finger tension anti-collision rod (21). Since there is a speed difference between the circular motions of the two, the relative speed difference of the circular motion will cause the finger connecting rod (12) with a faster circular speed to drive the finger distal knuckle (11) to perform bending motion. If a bolt fixing point of the finger base knuckle is regarded as the absolute instantaneous center of velocity, the bending motion of the finger can be regarded as a circular motion around the instantaneous center. The finger connecting rod (12) and the finger proximal knuckle housing (13) have different radii from the absolute instantaneous center to the first fixing point and the second fixing point of the finger distal knuckle (11), respectively. Therefore, under the same angular velocity, there is a speed difference in the circular motion. The finger is restored by adding a torsion spring (14) and a pre-tightening force is added so that the finger can be kept in a natural state; the torsion spring (14) is embedded in the connection point between the finger proximal knuckle shell (13) and the finger distal knuckle (11), one end of the torsion spring is embedded in the finger distal knuckle (11), and the other end is embedded in the groove of the finger connecting rod (12). When the finger is bent, an opposite torque is applied to the finger so that the finger is restored to the extended state without the motor doing work.

5. The mechanical bionic hand according to claim 3, characterized in that: The thumb mechanism (4) comprises a thumb distal knuckle (41), a thumb distal joint (42), a middle portion of a thumb rotating motor base (43), a thumb rotating motor base side plate (44), a thumb proximal knuckle housing (45), a motor fixing belt (47), a first bevel gear (48), and a transmission sheet (49); The thumb planetary gear transmission mechanism (5) comprises a second bevel gear (51), a third bevel gear (52), a first bearing (53), a second bearing (54), a planetary gear (55) of a planetary gear mechanism, a variable diameter shaft (56), a rotating sheet (57), a first axial fixing member (58), a sun gear (59) of a planetary gear mechanism, and a second axial fixing member (510); The thumb drive mechanism comprises a micro reduction motor (46); the micro reduction motor (46) is fixed to the middle part (43) of the thumb rotating motor base through a motor fixing belt (47); one end of the micro reduction motor (46) is connected to a first bevel gear (48), and the first bevel gear (48) is meshed with a second bevel gear (51); the second bevel gear (51) is installed on the first D-shaped shaft and is fitted together with the transmission plate; the rotation of the second bevel gear (51) can drive the first D-shaped shaft to rotate, thereby driving the transmission plate (49) to rotate; The transmission plate (49) is arranged close to the thumb proximal knuckle housing (45), and the rotation of the transmission plate (49) can push the thumb proximal knuckle housing (45), thereby pushing the thumb distal joint (42) to rotate, and driving the thumb distal knuckle (41) connected to the thumb distal joint (42) to rotate; The second bevel gear (51) is meshed with the third bevel gear (52) to drive the third bevel gear (52) to rotate, and the third bevel gear (52) is installed on the second D-shaped shaft, and then drives the planetary gear (55) to rotate through the second D-shaped shaft. A first bearing (53) and a second bearing (54) are respectively provided on both sides of the gear to enhance the stability of its movement and limit its axial displacement. The second D-shaped shaft is designed to be a variable diameter type, so the axial displacement of one end thereof is limited, while the displacement of the other end is limited by the first axial fixing member (58); the planetary gear (55) is meshed with the sun gear (59) fixed on the palm. Different from the planetary gear, the third D-shaped shaft of the sun gear is designed to be non-rotatable, and the shaft hole of its mounting base is also D-shaped, while the shaft hole of the mounting base of the planetary gear is circular; therefore, the sun gear (59) is stationary, and moves in a circle around the sun gear (59) under the restriction of the rotating plate (57); The bending movement and rotation movement of the thumb mechanism are linked, and the degree of bending is in a set proportion to the rotation angle, and when the micro reduction motor rotates, the bending direction of the thumb mechanism and the rotation direction of the thumb are both the same positive process or the same negative process; here, the natural extension of the thumb mechanism is used as the initial state of the bending movement, the thumb mechanism is placed on the side of the hand as the initial state of the thumb rotation movement, the process of the thumb mechanism from extension movement to complete bending is used as the positive direction, and the process of the thumb mechanism moving from the side of the hand to perpendicular to the hand is used as the positive process of the rotation movement.

6. The mechanical bionic hand according to claim 2, characterized in that: The mechanical bionic hand also includes a wrist, which is connected to the palm mechanism.

7. The mechanical bionic hand according to claim 2, characterized in that: The restoring mechanism comprises a torsion spring (14), which is used to restore the finger and add a pre-tightening force so that the finger can be kept in a natural state.

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