Mechanical human hand

Abstract

The invention relates to robotics and medicine, and more particularly to controllable manipulators and prosthetic extremities. The technical problem of providing a reliable mechanical hand that supports dexterity is solved by a mechanical hand comprising a wrist module and a palm module, the palm module having prosthetic metacarpal bones hingedly mounted thereto, the heads of which have finger prostheses mounted thereto comprising phalanges connected by joints. Mounted on each proximal and middle phalanx and on the metacarpal bone is a servomotor having a shaft which is connected via a reduction gear to a pin of a joint for bending and straightening the phalanges and spreading and closing the fingers. The palm module is mounted to the wrist module by linear servomotors for moving the palm module in different directions, the distal and proximal ends of the linear servomotors being equipped with hinged crosspieces. A motor with a reduction gear is mounted in the palm module, an output shaft of said motor being connected to the wrist module via a support bearing. Each of the servomotors and the motor of the palm module are equipped with control modules having a microcontroller and a control driver, the control modules being connected to a microprocessor of the hand, and each joint is equipped with a position sensor connected to a control module.

Description

[0001] MECHANICAL HUMAN HAND

[0002] DESCRIPTION

[0003] The invention relates to the fields of robotics and medicine, namely to controlled manipulators and limb prostheses [A61F 2 / 50, A61F 2 / 56, A61F 2 / 68, A61F 2 / 70, B25J 9 / 00, B25J 11 / 00].

[0004] A PROSTHESIS is known from the prior art [US2013053984A1, published: 28.02.2012], comprising a tendon having a part that engages with a movable element of the device in such a way that movement of the tendon in a given direction accordingly sets in motion said movable element, in which said part engages with said movable element, the tendon has an additional part, remote from the first mentioned part, which is connected to drive means of the device, the drive means comprises a linear drive, wherein the device is additionally provided with elastic means for acting on the movable element against the action of the tendon, when the latter moves in said given direction, the movable element comprises a phalanx, which comprises or is part of a finger connected to the palm of the prosthetic device, the drive means is fixed in the palm of the prosthetic device.

[0005] A prosthesis claimed in US2013053984A1, comprising at least two parts that can be movable relative to each other, a drive connected to move one of the parts relative to the other, and a control element connected for control depending on a signal supplied to the user to the control element, in which a motion converter is connected to the control element, as well as to an actuator for supplying signals to the control mechanism indicating the amount of movement produced by the actuator, and the control element controls the actuator depending on the signals it receives from the converter, the motion converter contains a digital pulse encoder. A HIGHLY ELASTIC PROSTHESIS OF A HAND WITH 15 DEGREES OF FREEDOM is known [IN201841027703A, published: 27.07.2018], comprising prosthetic fingers, a palm, a control unit, a finger separation unit, a base hinge, a second and third hinge joints, an assembled motor holder,drive cables, a spring-loaded slider assembly, a cable, guides, a voice recognition unit, in which 15 degrees of freedom and high flexibility of the prosthetic hand are achieved by using cables and pulley systems in the position of the joints, in which a total of 15 actuators were used to obtain the full motion of the human hand, in which a high-performance microcontroller and a motor driver are used to interface with the actuators, wherein a cable transmission is used from the actuators to transmit power from the actuator to the joints, wherein the highly flexible prosthetic hand is controlled using speech recognition, and speech recognition is carried out using neural networks, and the system can be trained to recognize the user's voice, wherein the highly flexible prosthetic hand can also be used for remote control in unsafe and dangerous conditions, the connecting joint is driven by a single actuator,The base hinge is connected to the finger separator hinge present on its lower finger portion.

[0006] Also known is an EMG-BASED LIMB PROSTHESIS FOR PATIENTS WITH AMPUTATED LIMBS [IN202241072882A, published: 12 / 30 / 2022], which includes:

[0007] 1) a plurality of 3D-printed body parts 1 assembled using a plurality of strings to form a limb-like structure, wherein said structure is installed by a practicing physician in place of amputated limbs; i2) a plurality of servomotors 2 built into each joint of said structure, wherein a muscle sensor 3 is manufactured on said structure in such a way that said sensor is in contact with a muscle of said amputee to determine electrical activity of a muscle of said amputee;

[0008] and 3) a microcontroller 4, connected to said sensor, processes said electrical activity of the muscles of said amputee and, accordingly, regulates the actuation of said servomotors 2, wherein, when said motor moves, said fishing lines are stretched or compressed to impart the required movement to a part of said structure to assist said amputee in turning or moving parts of said structure.

[0009] A ROBOTIC HAND DESIGN is known from the prior art [CN208132992U, published: 23.11.2018], including a forearm, a first servomotor, a metacarpal bone, characterized in that the inner part of the forearm is equipped with a controller and a battery group, a first servomotor, the forearm is equipped with a rotary table, the rotary table is provided with a mounting plate, and the surface of the mounting plate is provided with a first bearing, a second bearing and a rotating shaft inside the second bearing, the mounting plate is equipped with a second servo drive, the output end of the second servomotor is connected by the first rotating shaft to the second bearing, and the described surface of the first shaft and the rotating shaft is provided with a metacarpal bone, the distal side of the metacarpal bone is provided with a thumb, an index finger, a middle finger, a ring finger and a little finger, each finger includes a distal phalanx, the first joint, middle phalanx, second joint, proximal phalanx and third joint,each joint includes a 3rd bearing, a mini-servo drive and a second shaft, the 3rd bearing is fixedly connected to the top of the middle phalanx, a mini-servo drive is mounted on the 3rd bearing, the output shaft of the mini-servo drive is located above the middle phalanx on the inside and engages with the second shaft to connect with the 3rd bearing.,

[0010] The closest in technical essence is the PROSTHESIS [W00069375A1, published: 23.11.2003], comprising a frame, a plurality of elements pivotally mounted on said frame, a plurality of drives mounted on said frame and connected to said plurality of elements for driving at least one of said plurality of elements independently or simultaneously relative to another, the drives being servomotors, the elements being in the form of pins provided with at least one hinge, the drives being connected to sensors for detecting a desired movement and generating a signal in response thereto, a controller responsive to said sensor signal for generating control signals for input into said at least one actuator, wherein at least one of said actuators, receiving one of said signals, causes said at least one of said plurality of signals to move independently or simultaneously relative to another.

[0011] The main technical problem of the analogue and prototype is the small number of degrees of freedom, their low maintainability and reliability.

[0012] The objective of the invention is to eliminate the shortcomings of its analogues and prototype. The technical result of the invention is to enable the creation of a reliable mechanical hand for the human hand that supports the fine motor skills inherent in a biological hand.

[0013] The said technical result is achieved due to the fact that a mechanical hand of a human being is characterized by the fact that it contains a wrist block, a metacarpal block mounted thereto, including a base and prostheses of the metacarpal bones mounted in a hinged manner to the base, a prosthesis of the thumb, index, middle, ring fingers and little finger is mounted to the head of each of the prostheses of the metacarpal bones, containing sequentially connected to each other by a hinged prosthesis of the joint, the proximal, middle and distal phalanges, on each of the proximal and middle phalanges of the fingers and on the prosthesis of the metacarpal bone a servo drive is mounted, the shaft of which is connected through a gearbox to the hinge axis of the joint prosthesis with the possibility of independent flexion-extension of each of the phalanges of the finger prostheses and adduction-abduction of the finger prostheses due to the orthogonal arrangement of the axis of the hinge metacarpal joint to the finger prosthesis,The metacarpal block is movably mounted to the wrist block using linear traction servo drives with the ability to tilt the metacarpal block in different directions, wherein the distal and proximal ends of the said linear traction servo drives are provided with articulated crosspieces, a motor with a planetary gearbox is mounted in the metacarpal block, the output shaft of which is connected to the wrist block through a support bearing in the wrist block, wherein each servo drive and the motor of the metacarpal block are provided with separate control modules with a microcontroller and a driver for controlling the servo drive and the motor of the metacarpal block and is connected to the central microprocessor of the mechanical hand, and each joint is provided with joint axis position sensors, which are also connected to the control module.

[0014] In particular, the linear traction servos are mounted at the vertices of the triangle. Specifically, a quick-release rotary lock is mounted at the proximal end of the wrist block.

[0015] In particular, the control modules are equipped with connectors for their connection.

[0016] Figure 1 schematically shows a mechanical hand of a human being, its phalanges and hinges, on which are indicated: 1 - carpal block, 2 - base of the metacarpal block, 3 - metacarpal bone prostheses, 4 - proximal phalanx, 5 - middle phalanx, 6 - distal phalanx, 7 - distal interphalangeal joint, 8 - proximal interphalangeal joint, 9 - metacarpophalangeal joint, 10 - metacarpal joint, 11 - linear traction servo drives, 12 - hinge crosses, 13 - metacarpal block motor, 14 - support bearing, 15 - servo drives, 16 - position sensors.

[0017] Implementation of the invention.

[0018] The essence of the claimed technical solution is to provide the ability to precisely control a mechanical hand through multiple servo drives integrated directly into the joints and the implementation of a control system to provide the mechanical hand with the functions of a real hand.

[0019] A human mechanical hand is constructed of metal and plastic and comprises a carpal unit 1, a metacarpal unit mounted thereto, including a metacarpal unit base 2, and metacarpal bone prostheses 3 mounted to the base of the metacarpal unit 2. The metacarpal bone prosthesis 3 comprises a head at the distal end and a base at the proximal end. Finger prostheses are mounted to the heads of the metacarpal bone prostheses 3: the thumb, index, middle, ring, and little fingers. Each finger prosthesis comprises proximal phalanges 4, middle phalanges 5, and distal phalanges 6, connected sequentially by a hinged joint prosthesis.

[0020] A servo drive 15 is mounted within each of the proximal 4th and middle 5th phalanges of each finger prosthesis, as well as within each metacarpal bone prosthesis 3. Its shaft is connected via a gearbox to the hinge axis of the joint prosthesis, providing flexion and extension of the distal 6th, middle 5th, and proximal 4th phalanges of the finger prosthesis. Phalanges 4-6 themselves serve as external housings for servo drives 15 and gearboxes.

[0021] The distal phalanx 6 of the finger prosthesis is connected to the middle phalanx 5 by the distal interphalangeal joint 7, the hinge axis of which is connected via a gearbox to the shaft of the servo drive 15 installed inside the middle phalanx 5 and is driven by it. The middle phalanx 5 is connected to the proximal phalanx 4 by the proximal interphalangeal joint 8, the hinge axis of which is connected via a gearbox to the shaft of the servo drive 15 installed inside the proximal phalanx 4 and is driven by it. The proximal phalanx 4 is connected to the head of the metacarpal bone prosthesis 3 by the metacarpophalangeal joint 9, the hinge axis of which is connected via a gearbox to the shaft of the servo drive 15 installed inside the metacarpal bone prosthesis 3 and is driven by it.

[0022] The base of the metacarpal bone prosthesis 3 is mounted to the base of the metacarpal block 2 by the metacarpal joint 10, the hinge axis of which is connected via a gearbox to the shaft of the servo drive 16, installed inside the base of the metacarpal block 2 with the ability to set the metacarpal bone prosthesis 3 in motion from side to side, ensuring the closing and opening of the finger prostheses, for which purpose the axes of the metacarpal joints 10 are oriented orthogonally to the hinge axes of the joints 7-9 of the finger prostheses. The base of the metacarpal block 2 is movably mounted to the carpal block 1 by means of linear traction servo drives 11, predominantly three, located at the vertices of a triangle, with the ability to ensure an inclined movement of the metacarpal block in different directions. The distal and proximal ends of the said linear traction servo drives 11 are provided with articulated crosspieces 12, which ensure the tilt of the metacarpal block during the operation of the linear traction servo drives 11.

[0023] Between the linear traction servo drives 11, a motor of the metacarpal block 13 is mounted with a planetary gearbox, which ensures the rotation of the metacarpal block around its axis; for this purpose, the said motor 13 is connected by its shaft to the wrist block 1 through a support bearing 14, which ensures reliable fastening of the shaft of the motor of the metacarpal block 13 to the wrist block 1 and, accordingly, the connection of the metacarpal block to the wrist block 1.

[0024] The mechanical hand is connected to the forearm using a quick-release twist lock. This quick-release lock allows the mechanical hand to be mounted on a robotic arm and used as a robotic manipulator.

[0025] Each servo drive 15, including the linear 11 and the metacarpal block motor 13, is equipped with a separate control module, made in the form of a printed circuit board, on which a microcontroller and a driver for controlling the servo drive motor 15 or the metacarpal block motor 13 are mounted.

[0026] The control modules of the servo drives and the motor of the metacarpal block are connected to the central microprocessor, which is equipped with a mechanical hand with the ability to control the microprocessor through the mentioned control modules of the servo drives and the motor of the metacarpal block.

[0027] Mounted on each axis of the joint 7-9, the hinge crosspiece 12, and the shaft of the metacarpal block motor 13 is a position sensor 16. This sensor records the position of the prosthetic finger phalanx 4-6, the metacarpal bone prosthesis 3 relative to the base of the metacarpal block 2, and the metacarpal block relative to the carpal block 1, and transmits data to the central microprocessor. Position sensor 16 can be implemented as a digital or analog sensor, for example, in the form of an encoder, potentiometer, etc.

[0028] The central microprocessor controls the mechanical brush, which is programmed and activated in several ways:

[0029] 1) a motion capture glove worn on a human biological hand, containing position sensors for each of the finger joints, signals from which are picked up, digitized by a microcontroller built into the glove and transmitted to the central microprocessor of the mechanical hand, for example, using a wireless personal area network (WPAN).The central microprocessor, based on the data received from the motion capture glove, sends corresponding signals to the control modules of the servo drives of the finger prostheses, the linear traction drives 11 and the motor of the metacarpal block 13 for controlling the said servo drives 15 and the motor 13 with the possibility of their rotation and movement of the finger prostheses, the metacarpal bones 3, the metacarpal block similar to the perfect movement of a biological human hand; 2) an image capture camera (computer vision method), mounted on a mechanical hand, for example, on the base of the metacarpal block 2 on the inner or outer side, or on the tip of the distal phalanx 6 of the finger prosthesis, with the help of which an image of the object, the capture of which is planned to be performed, is captured, the image is recognized and the object is identified (shape, weight, size and hardness of the object) using a recognition system, the operation of which is based on machine (deep) learning.Based on the results of object recognition and the activation of a proximity sensor (not shown in the figures) mounted on a mechanical hand, when the hand approaches the object or the object approaches the hand, a grip (the position of the finger prostheses, metacarpal bones 3 and metacarpal block) of the hand is automatically formed, which is recorded (programmed) in advance using preliminary machine (deep) learning for the identified object; 3) using voice control, which ensures the formation of one of the programmed grips, through voice commands transmitted to the central microprocessor through a microphone, which can be either built into the mechanical hand or be separate, but in any case connected to the central microprocessor by known methods (wired or wireless).After recognizing the voice command, the central microprocessor sends the corresponding signals to the control modules of the servo drives, linear traction drives 11, and the motor of the metacarpal block 13 for their operation;

[0030] 4) using patterns (sequences of grips) stored in the memory of the central microprocessor, to ensure standard actions (applications) using voice commands, using a mobile device application, data obtained from the results of identifying an object using computer vision, data from myosensors (when used as a prosthesis);

[0031] 5) using an application on a mobile device (phone, tablet), where one of the preset grips or patterns is selected and using the connection of the mobile device with the central microprocessor, information is transmitted, including data for each control module of the servo drives, linear traction drives 11, and the motor of the metacarpal block 13;

[0032] 6) myosensors when using a mechanical hand as a prosthesis, installed on the muscle, providing a programmed position of the hand, or acting as programmable event buttons when, upon triggering the sensor, a programmed action is performed;

[0033] 7) various combinations of the methods listed above;

[0034] 8) remotely, controlling the independent movement of the detached hand using a mobile device (smartphone, tablet, etc.) used as a remote control. The mechanical hand moves through the fingers, similar to those of a spider, and is coordinated by a camera mounted on the hand.

[0035] When used as a prosthetic, the mechanical hand is equipped with a rechargeable battery that powers the prosthesis's electrical components. The battery is charged using a charging station. Charging the battery is done manually or automatically:

[0036] a) a mechanical hand removed from a biological hand and left near a charging station determines, using a camera or a signal from the charging station transmitted in the form of a sound signal or via a communication channel supported by the mechanical hand, the location of the charging station and, moving with its fingers, similar to the movements of arachnids, independently moves to the charging station and begins the charging process.

[0037] b) replacing the battery with a charged one.

[0038] The main, previously inaccessible, capabilities of fine motor skills for various hand prostheses and manipulators become available, first of all, thanks to individual servo drives 15, which ensure the movement of all phalanges of the finger prostheses, including the distal 6, servo drives 15, which ensure the movement of the metacarpal bone prostheses 3 from side to side, linear traction drives 11, which ensure the movement of the metacarpal block in all planes, the motor of the metacarpal block 13, which ensures the rotation of the metacarpal block and the methods of interaction of the user with the mechanical hand.

[0039] The claimed mechanical hand enables fine motor skills development thanks to a separate servo drive (15) for each phalanx, particularly the distal 6, of the finger prostheses, the thumb prosthesis, and the metacarpal bone prostheses (3), which enable lateral opening / closing of the finger prostheses via individual metacarpal joints (10). The design also enables movement of the metacarpal block via linear traction drives (11) and articulated crosspieces (12), as well as a metacarpal block motor (13), which is not implemented in any similar devices to the claimed invention or in existing products. This mechanical hand design allows for highly accurate replication of the movements of a biological human hand and the implementation of fine motor skills.

[0040] By utilizing phalanges 4-6 of the finger prostheses as external housings for servo drives 1 and gearboxes, the resistance of servo drives 4 to external impacts is increased and the load on the output shafts of servo drives 15 is reduced compared to those mounted directly to the joint hinge axis, as in existing analogs and finished products. This design ensures high repairability of the finger prosthesis, as replacing a phalanx of the finger prosthesis, should its hinge or servo drive 15 (gearbox), as well as the transmission between servo drive 15 and the hinge, simply requires replacing the specified component with a serviceable one. This, in turn, allows for repairs to be performed in limited conditions, including at home, thereby reducing repair time and improving the efficiency of the hand restoration.This is also influenced by the manufacture of the servo drive and motor 13 control modules as separate elements mounted next to the servo drive 15 and motor 13. Equipping the aforementioned control modules with connectors ensures their quick-release connection / disconnection, which also affects maintainability.

[0041] The mechanical hand is a high-tech product in its manufacture, possessing 36 degrees of freedom, 20 of which are provided by servo drives 14 of the finger prostheses and metacarpal bones 3, 15 by linear traction drives 11 and articulated crosspieces 12, and 1 by the motor of the metacarpal block 13.

Claims

FORMULA 1. A mechanical hand of a human being, characterized in that it contains a carpal block, a metacarpal block mounted thereto, including a base and prostheses of the metacarpal bones mounted in a hinged manner to the base, a prosthesis of the thumb, index, middle, ring fingers and little finger is mounted to the head of each of the prostheses of the metacarpal bones, containing proximal, middle and distal phalanges sequentially connected to each other by a hinged prosthesis of the joint, a servo drive is mounted on each of the proximal and middle phalanges of the fingers and on the prosthesis of the metacarpal bone, the shaft of which is connected through a gearbox to the hinge axis of the joint prosthesis with the possibility of independent flexion-extension of each of the phalanges of the finger prostheses and adduction-abduction of the finger prostheses due to the orthogonal location of the axis of the hinge metacarpal joint to the finger prosthesis,The metacarpal block is movably mounted to the wrist block using linear traction servo drives with the possibility of tilting the metacarpal block in different directions, wherein the distal and proximal ends of the said linear traction servo drives are provided with articulated crosspieces, a motor with a planetary gearbox is mounted in the metacarpal block, the output shaft of which is connected to the wrist block through a support bearing in the wrist block, wherein each servo drive and the motor of the metacarpal block are provided with separate control modules with a microcontroller and a driver for controlling the servo drive and the motor of the metacarpal block and is connected to the central microprocessor of the mechanical hand, and each joint is provided with a joint axis position sensor, which is also connected to the control module.

2. A mechanical brush according to claim 1, characterized in that the linear traction servo drives are mounted at the vertices of the triangle.

3. A mechanical hand according to claim 1, characterized in that a rotary quick-release lock is mounted on the proximal end of the wrist block.

4. A mechanical brush according to claim 1, characterized in that the position sensor is made in the form of an encoder.

5. A mechanical brush according to claim 1, characterized in that the control modules are equipped with connectors for their connection.

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