A multi-air chamber humanoid joint type soft thumb

Abstract

The present application belongs to the technical fields of artificial limb manufacturing, and discloses a multi-air chamber human-like joint type soft thumb, which comprises a soft shell, a silica gel tube, a bellows and an interface, wherein the silica gel tube comprises an inner silica gel tube, the inner silica gel tube comprises an upper tube and a lower tube connected in sequence, the upper end of the upper tube is sealed, the lower tube comprises a main branch pipe and two auxiliary branch pipes, the main branch pipe is through the upper tube, and the outer portions of the upper tube, the main branch pipe and the two auxiliary branch pipes are all wound with fiber lines in a symmetrical double helix form; the soft shell is arranged at the periphery of the upper tube, the bellows is arranged at the periphery of the lower tube, the upper portion of the bellows is connected with the lower portion of the soft shell, the lower portion of the bellows is connected with the interface, three openings are arranged on the interface and connected with the main branch pipe and the two auxiliary branch pipes respectively. The present application overcomes the characteristics of single function, insufficient output and poor human-likeness of the existing mechanical thumb.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field related to artificial limb manufacturing, and more particularly, to a multi-air-cavity human-imitating joint type soft big thumb. BACKGROUND

[0002] Human hands play a vital role in life, and human hands have extremely strong dexterity, which is the key to completing grasping objects and other complex tasks, but there are a large number of hand amputation patients and congenital hand deformity populations worldwide, and the lack of hands brings great inconvenience to their lives. Considering the large difference in residual limb and residual palm of each patient in this group, developing a functional and appearance-imitating artificial hand has extremely important scientific research significance and social value. In fact, in addition to humans, only a few animals have opposable thumbs. The thumb is more complex in movement and has stronger carrying capacity than the other four fingers, and the grasping ability based on the cooperation of the thumb and the other four fingers is the premise of human manufacturing and using tools. Therefore, for patients with thumb loss, a mechanical thumb with appropriate size, appearance and multiple functions is necessary.

[0003] There are currently some research and applications on mechanical thumbs, but in order to ensure the degrees of freedom and output force of the thumb, traditional mechanical fingers use multiple motors and metal structures for movement mechanisms. Multiple motors and the overall use of metal structures result in a large volume and weight of traditional mechanical thumbs. To solve the above problems, Chinese patent CN106344222A uses a worm drive to achieve flexion and lateral swing movements with only one motor, but due to the limitation of the number of drivers, the movement trajectory of the thumb is limited to a fixed plane. Chinese patent CN106965200A proposes a pneumatic soft mechanical hand, in which the soft thumb has three air chambers for bending in three directions, and the air chambers are arranged at equal arc intervals. This structure ensures high flexibility of the thumb, but the overall result and output force size are different from those of an actual human thumb, making it difficult for the mechanical finger to be accepted by hand disabled patients. Therefore, there is an urgent need to design a flexible, convenient and small thumb. SUMMARY

[0004] In view of the above defects or improvement needs of the prior art, the present application provides a human-imitating multi-joint soft thumb, which overcomes the characteristics of single function, insufficient output and poor humanization of existing mechanical thumbs.

[0005] To achieve the above object, the application provides a multi-air chamber humanoid joint type soft thumb, which comprises a soft shell, a silica gel tube, a bellows and an interface, wherein the silica gel tube comprises an inner silica gel tube, the inner silica gel tube comprises an upper tube and a lower tube connected in sequence, the upper end of the upper tube is sealed, the lower tube comprises a main branch pipe and two auxiliary branch pipes, the main branch pipe is through the upper tube, and the outer part of the upper tube, the main branch pipe and the two auxiliary branch pipes are all wound with fiber lines in a symmetrical double helix form; the soft shell is arranged on the periphery of the upper tube, the bellows is arranged on the periphery of the lower tube, the upper part of the bellows is connected with the lower part of the soft shell, the lower part of the bellows is connected with the interface, and three openings are arranged on the interface and connected with the main branch pipe and the two auxiliary branch pipes.

[0006] Preferably, the silica gel tube further comprises an outer silica gel tube, and the outer silica gel tube is wrapped on the periphery of the inner silica gel tube.

[0007] Preferably, the soft shell comprises two trapezoidal hollows, and the two trapezoidal hollows correspond to the interphalangeal joint and the metacarpophalangeal joint of the thumb respectively; and the bending modulus of the trapezoidal hollows of the soft shell is smaller than that of other parts.

[0008] Preferably, the bottom side of the trapezoidal hollow corresponding to the metacarpophalangeal joint in the soft shell is larger than the size of the trapezoidal hollow corresponding to the interphalangeal joint.

[0009] Preferably, the upper tube is in a mouth-shaped cross section, and one side of the mouth-shaped cross section is in a circular arc shape and corresponds to the outer surface of the thumb.

[0010] Preferably, the two auxiliary branch pipes are arranged on the two sides of the main branch pipe, and fiber lines are embedded on the center line of the connecting line of the two auxiliary branch pipe axes.

[0011] Preferably, the main branch pipe and the auxiliary branch pipe are in a circular truncated cone shape, and the large end is connected with the interface.

[0012] Preferably, the material of the soft shell is rubber.

[0013] Preferably, the bellows is gradually reduced in size along the silica gel tube.

[0014] Overall, compared with the prior art, the humanoid multi-joint soft thumb provided by the application mainly has the following beneficial effects:

[0015] 1. The main branch pipe can control the flexion and extension of the thumb, the two auxiliary branch pipes can control the side swing of the thumb, the soft shell and the bellows can realize the humanoid appearance of the soft thumb in the resting state and the gripping process, the appearance, function and operation correspondence of the soft thumb are guaranteed to be humanoid, and the user experience is greatly improved.

[0016] 2. The auxiliary branch of the present application only exists in the lower part, and is matched with the fiber line parallel to the axis in the silica gel tube. The axis of the main and auxiliary branches is perpendicular to the connecting line of the fiber line, which ensures that the auxiliary branch only participates in the side swing operation, so that the overall stiffness is not reduced by mutual extrusion in the composite motion. Compared with the traditional three-chamber bending soft actuator with equal-arc air cavity, the present application has higher output force and bending efficiency.

[0017] 3. The flexion and extension motion is realized by the upper tube penetrating through the thumb and the main branch, and the side swing motion is realized by the auxiliary branch only existing in the lower part of the thumb. Correspondingly, the flexion and extension motion of the human hand is completed by the wrist metacarpal joint, the metacarpal joint, and the fingertip joint, and the side swing motion is completed by the wrist metacarpal joint in the lower part of the thumb. Therefore, the joint corresponding to the chamber driving the soft thumb motion is consistent with the three joint motion functions of the human thumb, and has a human-like driving mode.

[0018] 4. The upper tube, the main branch, and the two auxiliary branches are externally wound with fiber lines in a symmetrical double helix form, which ensures that the fiber lines limit the radial expansion when inflated in the interior, realizing bending or side swing. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a schematic diagram of the external structure of the human-like multi-joint soft thumb of the embodiment of the present application;

[0020] Figure 2 is a schematic diagram of the internal structure of the human-like multi-joint soft thumb of the embodiment of the present application;

[0021] Figure 3 is an exploded schematic diagram of the human-like multi-joint soft thumb of the embodiment of the present application, wherein a is a schematic diagram of the internal silica gel tube, b is a schematic diagram of the soft shell, c is a schematic diagram of the corrugated tube, d is a schematic diagram of the interface, and e is a schematic diagram of the external silica gel tube;

[0022] Figure 4 is a schematic diagram of the silica gel tube of the embodiment of the present application, wherein a is a schematic diagram of the lower part of the silica gel tube, and b is a schematic diagram of the upper part of the silica gel tube;

[0023] Figure 5 is a schematic diagram of the installation of the human-like multi-joint soft thumb of the embodiment of the present application.

[0024] In all the drawings, the same reference signs are used to represent the same elements or structures, wherein:

[0025] 100-soft shell:

[0026] 110-tapered hollow:

[0027] 200-silica gel tube:

[0028] 210 - inner silica gel tube; 211 - upper tube; 212 - lower tube; 2121 - main branch tube; 2122 - auxiliary branch tube; 2123 - fiber line; 220 - outer silica gel tube;

[0029] 300 - bellows;

[0030] 400 - interface. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0032] The present application provides a soft-bodied multi-joint thumb, as shown in Figure 1 and Figure 2 The thumb comprises a soft-bodied shell 100, a silica gel tube 200, a bellows 300 and an interface 400.

[0033] As shown in a-e in Figure 3 The silica gel tube 200 comprises an inner silica gel tube 210, which comprises an upper tube 211 and a lower tube 212 connected in sequence, and the hardness of the inner silica gel tube 210 is preferably Shore hardness 15HA. As shown in Figure 4 The upper end of the upper tube 211 is sealed, the lower tube 212 comprises a main branch tube 2121 and two auxiliary branch tubes 2122, and the main branch tube 2121 penetrates the upper tube 211. The size of the main branch tube 2121 is larger than that of the two auxiliary branch tubes 2122, and the two auxiliary branch tubes 2122 are symmetrically arranged along the main branch tube 2121. A fiber line 2123 is embedded on the center line of the axis connecting the two auxiliary branch tubes 2122, that is, the lower tube region. In the pressurized state, the axially elongated chamber will exert a torque bending towards the fiber line. By adjusting the position of the fiber line 2123, in a further preferred embodiment, the fiber line 2123 is perpendicular to the two connecting lines of the axis of the main branch tube 2121 and the auxiliary branch tube 2122, so that the deformation forces generated by the main branch tube 2121 and the auxiliary branch tube 2122 are perpendicular to each other, which can ensure that the auxiliary branch tube 2122 will not be extruded by the main branch tube 2121 during bending, thereby preventing the main branch tube 2121 from participating in the flexion and extension movement, and improving the bending efficiency and output force of the soft-bodied thumb.

[0034] In a further preferred embodiment, the main branch tube 2121 and the auxiliary branch tube 2122 are circular truncated cones, and the large end is connected to the interface.

[0035] Further preferably, the upper tube 211 has a cross section in the shape of a square with rounded corners, and one of the rounded corners corresponds to the outer surface of the thumb.

[0036] The outer surfaces of the upper tube 211, the main branch tube 2121 and the two auxiliary branch tubes 2122 are all provided with fiber lines wound in the form of symmetrical double helixes. Further preferably, the outer surfaces of the upper tube, the main branch tube and the two auxiliary branch tubes are all provided with thread grooves for guiding the winding of the fiber lines, and the weaving inclination angle of the fiber lines wound in the form of symmetrical double helixes is a fixed value within the range of 3° to 6°.

[0037] The silica gel tube 200 further comprises an outer silica gel tube 220, which is wrapped around the periphery of the inner silica gel tube 210, and the outer silica gel tube 220 integrates the inner silica gel tube 210 by virtue of the curing property of silica gel.

[0038] The soft shell 100 is preferably made of rubber, and has a hardness of Shore 45HA. The soft shell 100 is arranged around the periphery of the upper tube 211, and has a design simulating the appearance of a human hand, with the knuckles at the bottom of the shell being raised and the distal phalangeal tips being contracted. The lower part of the soft shell 100 corresponds to the metacarpal joints, and the bending modulus of the parts corresponding to the interphalangeal joints and the metacarpophalangeal joints is smaller than that of other parts. Further preferably, the soft shell 100 comprises two trapezoidal hollows 110 corresponding to the interphalangeal joint and the metacarpophalangeal joint of the thumb, respectively. Under the condition of pressure, the axial elongation of the silica gel tube 200 causes the upper tube 211 to press and deform the soft shell 100, and the difference in rigidity of the soft shell 100 at different positions causes the shell to bend only at the notches. The difference in length of the notches ensures that the bending proportion corresponds to the fixed bending proportion of the human finger joints, and the lengths of the two joints and the soft shell correspond to the lengths of the phalangeal bones of the human hand.

[0039] The bellows 300 are arranged around the periphery of the lower tube 212, and the upper part of the bellows 300 is connected to the lower part of the soft shell 100, and the lower part of the bellows 300 is connected to the interface 400. The interface 400 is provided with three openings, which are connected to the main branch tube 2121 and the two auxiliary branch tubes 2122, respectively, and the cross-sectional size of the main branch tube is larger than that of the auxiliary branch tubes. Further preferably, the size of the bellows 300 gradually decreases along the silica gel tube, and the appearance of the bellows 300 is similar to that of the proximal phalanx of the thumb, thereby embodying the humanization of the overall appearance.

[0040] The main pipe 2121 of the silicone tube mainly undertakes the soft thumb flexion and extension movement and ensures the overall stiffness, and the two pairs of branch pipes 2122 undertake the lateral swing movement of the thumb. The soft thumb utilizes the stiffness difference of the soft shell 100 to ensure that the bending proportion at the joint is consistent with the bending proportion of the metacarpophalangeal joint and the interphalangeal joint of the human hand thumb. The proximal end of the soft thumb is used for three air chambers for bending in all directions instead of the saddle-shaped carpometacarpal joint at the base of the human finger, to realize large-range movement of the thumb. Since the carpometacarpal joint, metacarpal joint and fingertip joint of the human hand are involved in movement when the thumb is flexed and extended, the soft thumb uses the stretching and rebounding of the upper pipe 211 and the main branch pipe 2121 to replace the coordinated movement of the above three joints; since only the carpometacarpal joint is involved in movement when the human thumb swings laterally, the soft thumb uses the two auxiliary branch pipes 2122 to replace the lateral swing movement of the above joint. Therefore, under the premise of ensuring the human function of the soft thumb, the number of drivers is reduced, the motion function and the motion corresponding relationship are realized, and the humanization is realized.

[0041] The application provides a multi-joint soft thumb of an artificial hand. A hand disabled patient can replace the missing part with the soft thumb according to the self condition, such as Figure 5 As shown in the figure, after the soft finger is fixed with the palm, the artificial hand can complete daily life tasks, and the pressure equipment for controlling the soft thumb can adopt conventional air pressure and hydraulic equipment, such as an electric air compressor, a foot-driven air pump, an electric hydraulic machine and the like.

[0042] Those skilled in the art can easily understand that the above description is only the preferred embodiment of the present application, and is not used to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A multi-cavity, human-articular soft thumb, characterized in that, The thumb comprises a soft shell (100), a silica gel tube (200), a bellows (300) and an interface (400), wherein: The silica gel tube (200) comprises an inner silica gel tube (210), which comprises an upper tube (211) and a lower tube (212) connected in sequence, wherein the upper end of the upper tube (211) is sealed, the lower tube (212) comprises a main branch tube (2121) and two auxiliary branch tubes (2122), the main branch tube (2121) penetrates the upper tube (211), and the outer portions of the upper tube (211), the main branch tube (2121) and the two auxiliary branch tubes (2122) are all wound with fiber lines in a symmetrical double helix form; The soft shell (100) is arranged at the periphery of the upper tube (211), the bellows (300) is arranged at the periphery of the lower tube (212), the upper portion of the bellows (300) is connected with the lower portion of the soft shell (100), the lower portion of the bellows (300) is connected with the interface (400), and three openings are arranged on the interface (400) and connected with the main branch tube (2121) and the two auxiliary branch tubes (2122); The two auxiliary branch tubes (2122) are arranged on the two sides of the main branch tube (2121), and a fiber line (2123) is embedded on the center line of the axis of the two auxiliary branch tubes (2122); The main branch tube (2121) of the silica gel tube bears the flexion and extension movement of the soft thumb and ensures the overall rigidity, and the two auxiliary branch tubes (2122) bear the lateral swing movement of the thumb; the proximal end of the soft thumb is provided with three air chambers for bending in all directions to replace the carpometacarpal joint of the human finger root, so that a large range of movement of the thumb is realized.

2. The thumb of claim 1, wherein, The silica gel tube (200) further comprises an outer silica gel tube (220) wrapped at the periphery of the inner silica gel tube (210).

3. The thumb of claim 1, wherein, The lower portion of the soft shell (100) corresponds to the metacarpophalangeal joint, the bending modulus of the corresponding part of the soft shell (100) to the interphalangeal joint and the corresponding part to the metacarpophalangeal joint is smaller than that of other parts.

4. The thumb of claim 1 or 3, wherein, The soft shell (100) comprises two trapezoidal hollows (110) corresponding to the interphalangeal joint and the metacarpophalangeal joint of the thumb.

5. The thumb of claim 1, wherein, The upper tube (211) has a cross section in the shape of a mouth, and one side of the mouth-shaped section is in the shape of a circular arc corresponding to the outer surface of the thumb.

6. The thumb of claim 1, wherein, The main branch tube (2121) and the auxiliary branch tube (2122) are in the shape of a circular truncated cone, and the large end is connected with the interface.

7. The thumb of claim 1, wherein, The material of the soft shell (100) is rubber.

8. The thumb of claim 1, wherein, The bellows (300) gradually reduces in size along the silica gel tube.

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