CN109984875A

CN109984875A - A kind of bionic mechanical artifucial limb and control method

Info

Publication number: CN109984875A
Application number: CN201910359729.0A
Authority: CN
Inventors: 李辰熹
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2019-07-09

Abstract

The invention discloses a bionic mechanical prosthesis and a control method, and relates to the technical field of prosthetics, including a prosthetic palm shell, a prosthetic finger mechanism and an external airbag mechanism; a motor control end inside the prosthetic palm shell is connected to a muscle electrical signal sensor through electrical signals; The inner side of the segmented structure is provided with a first pressure sensor and a thermistor; the first pressure sensor is connected to the external airbag mechanism through an electrical signal, and the thermistor is connected to the heating element through an electrical signal; by setting the thermistor and the heating element , so that the prosthetic limb can make the other party feel a comfortable temperature during the driving etiquette action, which is convenient to properly care for the other party in the process of daily communication, and avoid the other party holding a cold machine during the handshake process; During the driving etiquette action, the user can perceive the strength of the other party and improve the user's sense of participation. By setting the muscle electrical signal sensor, the prosthetic limb can be stretched or tightened.

Description

Bionic mechanical artificial limb and control method

Technical Field

The invention relates to the technical field of artificial limbs, in particular to a bionic mechanical artificial limb and a control method thereof.

Background

In the existing artificial limb structure, the daily simple actions of the disabled can be met, for example: holding a cup to drink water, holding a spoon to drink soup, holding fresh flowers and bread and other light things and extracting articles; designers often overlook the handicapped's need for etiquette interaction, for example: handshake, the designed artificial limb structure is not humanized enough, and in addition, the process of learning and using the artificial limb by the disabled is long and difficult;

therefore, a bionic mechanical artificial limb is urgently needed at present, the etiquette interaction between disabled people and other people can be better met, the life of the disabled people is facilitated through the etiquette actions, and more confidence is added to the disabled people.

Disclosure of Invention

The invention provides a bionic mechanical artificial limb and a control method thereof aiming at the problems of the background art, which can enable the opposite side to sense the temperature and the touch strength of the opposite side, and simplify the use difficulty of the bionic mechanical artificial limb.

In order to achieve the purpose, the invention provides a bionic mechanical artificial limb, which comprises an artificial limb palm shell, an artificial limb finger mechanism, an external air bag mechanism and at least one muscle electric signal sensor, wherein the artificial limb palm shell is provided with a palm shell body; wherein,

a motor is arranged in the artificial limb palm shell, the control end of the motor is connected with a muscle electrical signal sensor through an electrical signal, the output shaft of the motor is connected with an artificial limb finger mechanism through a tensioning wire, and the output shaft of the motor rotates to drive the artificial limb finger to grab and relax; a heating body is arranged on the outer side of the limb palm shell;

the artificial limb finger mechanism comprises a plurality of finger structures, the top end in each finger structure is fixedly connected with the tensioning line, each finger structure comprises a plurality of segmented structures, the segmented structures are connected through shafts to simulate finger joints, and a first pressure sensor and a thermistor are arranged on the inner side of each segmented structure; the first pressure sensor is connected with the external air bag mechanism through an electric signal, and the thermistor is connected with the heating body through an electric signal;

the external air bag mechanism is arranged on the outer side of a hand or an arm of a user and comprises an air bag, an inflator pump and a second pressure sensor, the inflator pump is connected with the air bag through a pipeline, and the second pressure sensor is arranged on the contact surface of the air bag and a human body.

Preferably, a buffer mechanism is further arranged inside the artificial limb palm shell.

Preferably, the buffer mechanism is specifically: and the springs are connected with the tensioning lines in the finger structures.

Preferably, the first pressure sensor and the second pressure sensor both adopt flexible film pressure sensors; the thermistor adopts a thin film thermistor; the heating body adopts a flexible heating film.

Preferably, the first pressure sensor, the thermistor and the heating element are provided with antiskid silica gel on the outer sides.

Preferably, the at least one muscle electrical signal sensor, in particular arranged at the flexor hallucis longus of the arm of the user, is used for acquiring electrical signals of the thumb and electrical signals of the other four fingers, respectively.

The invention also provides a control method adopting the bionic mechanical artificial limb, which comprises the following steps:

collecting muscle electric signals of the arm of a user, processing the muscle electric signals, sending control signals to a motor, and controlling the rotation of the motor so as to drive the grabbing and the relaxation of the artificial limb finger;

collecting pressure signals of the contact surface of the inner side of the artificial limb finger mechanism and pressure signals of the contact surface of the air bag and the human body, and controlling the inflator pump by judging and comparing the pressure signals in real time;

the temperature signal of the inner side contact surface of the artificial limb finger mechanism is collected and is judged and compared with the temperature signal of the heating element in real time so as to control the heating element to heat.

Preferably, the pressure signal of the contact surface of the inner side of the artificial limb finger mechanism and the pressure signal of the contact surface of the air bag and the human body are collected, and the pressure signal is judged and compared in real time to control the inflator pump, specifically:

judging whether the pressure signal of the inner side contact surface of the artificial limb finger mechanism is greater than the pressure signal of the contact surface of the air bag and the human body, if so, controlling the air pump to inflate the air bag; otherwise, the operation of the inflator is stopped.

Preferably, the temperature signal of the inner side contact surface of the artificial limb finger mechanism is collected, and the temperature signal is judged and compared with the temperature signal of the heating element in real time to control the heating element to heat, specifically:

judging whether the temperature signal of the inner side contact surface of the artificial limb finger mechanism is greater than the temperature signal of the heating element, if so, controlling the heating element to continue heating; otherwise, the operation of the heating element is stopped.

The invention provides a bionic mechanical prosthesis and a control method, wherein the thermistor and the heating body are arranged, so that the prosthesis can sense comfortable temperature when the opposite side performs joint movement, the opposite side is convenient to be concerned properly in the daily communication process, the surface of the prosthesis is kept constant in the process of holding the etiquette, and the condition that the opposite side holds a machine which is cold ice and ice in the process of holding the hand and is not warm by people is avoided; through setting up external gasbag mechanism, realize that the artificial limb makes user self can the perception opposite side's dynamics when the etiquette action of traveling, improve the participation sense that the user used, through setting up muscle signal of telecommunication sensor, carry out muscle signal of telecommunication and gather, the action that the artificial limb extended or tightened up is carried out in the rotation of control motor.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a block diagram of a bionic mechanical prosthetic control system according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a bionic mechanical prosthesis according to an embodiment of the present invention;

FIG. 3 is a schematic illustration of a palm shell of a prosthetic in one embodiment of the present invention;

FIG. 4 is a schematic diagram of a prosthetic finger mechanism in accordance with an embodiment of the present invention;

FIG. 5 is a diagram illustrating test results in accordance with an embodiment of the present invention;

FIG. 6 is a schematic structural view of an external airbag mechanism according to an embodiment of the present invention;

FIG. 7 is a flow chart of a method for controlling a biomimetic mechanical prosthetic in one embodiment of the present disclosure;

FIG. 8 is a flowchart illustrating step S102 in accordance with an embodiment of the present invention;

FIG. 9 is a flowchart illustrating step S103 according to an embodiment of the present invention;

description of reference numerals:

1-artificial limb palm shell, 2-artificial limb finger mechanism, 3-external air bag mechanism, 4-muscle electric signal sensor, 104-buffer mechanism, 1041-spring, 105-control chip, 106-heating element, 201-finger structure, 2011-segmented structure, 2013-thermistor, 2015-antiskid silica gel, 301-air bag, 302-inflator pump, 303-second pressure sensor;

the implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The invention provides a bionic mechanical artificial limb, which is characterized in that as shown in figure 1, the structure is optimized by specially grasping articles, drinking water and the like in a handshake etiquette and life, muscle electric signals are adopted to obtain the intention of a user to act, and a temperature and pressure feedback integrated module is adopted to feed back information to the user; collected muscle electric signals, pressure and temperature are processed by the chip in a unified way and fed back to the action module to control the feedback device to work in action, pressure and temperature feedback;

the first preferred embodiment, as shown in fig. 2, comprises: the artificial limb palm shell 1, an artificial limb finger mechanism 2, an external air bag mechanism 3 and at least one muscle electric signal sensor 4 arranged on the arm of a user;

in the embodiment of the invention, the external main structures of the artificial limb palm shell 1 and the artificial limb finger mechanism 2 are made by adopting a 3D printing technology;

as shown in fig. 3, servo motors 101, 102, a tightening wire 103, a buffer mechanism 104 and a control chip 105 are arranged inside the artificial limb palm shell 1, the control ends of the motors 101, 102 are connected with at least one muscle electrical signal sensor 4 arranged on the arm of the user through the electrical signal of the control chip 105, the output shafts of the motors 101, 102 are connected with the artificial limb finger mechanism 2 through the tightening wire 103, and the output shafts of the motors 101, 102 rotate to drive the grabbing and relaxing of the artificial limb finger; a heating body 106 is arranged on the outer side of the artificial limb palm shell 1; the buffer mechanism 104 is specifically: 5 springs 1041, the springs 1041 are connected with the tightening lines 103 inside each finger structure 201;

in the embodiment of the invention, the adopted double servo motors 101 and 102 separately and independently control the thumb and the other four fingers, namely the thumb and the other four fingers are asynchronous and have different speeds; the four fingers moving synchronously adopt different springs 1041 to control the stress of the fingers to be different in magnitude; the fingers are reset by adopting different springs 1041, tension wires 103 (steel ropes) used for driving the fingers to contract and grab objects are different from the springs 1041, the objects to be grabbed are mainly stressed on a thumb, an index finger and a middle finger through adjustment among different combinations of the different springs 1041, the springs 1041 can play a role in protecting mechanisms and stress buffering, and the motion precision of the servo motors 101 and 102 can be compensated, so that the grabbing is more flexible and stable;

in the embodiment of the invention, when the hand muscle is stretched and contracted, the changed muscle is approached by the electric signal sensor, and weak electric signals are input into the electric signal acquisition rectification circuit; an integrated signal is obtained through the integrated processing of the signal, the collected signal can be filtered to compare the signal waveform by adopting a Myoware muscle electric signal collection module, and the simple signal can be output to carry out external control through a single chip microcomputer by adopting the Arduino system for analysis processing at present because the signal waveform is complex;

in the embodiment of the invention, the heating element 106 is a flexible heating film, and particularly, the flexible heating film is selected as the heating material of the product due to the fact that the heating speed is high, the power consumption is low, and the flexible heating film has a constant temperature characteristic in practice. The heating material can generate heat after being powered on, in the process of controlling the temperature, an NTC thermistor is placed on the surface of the film, and the heating stops working after the temperature reaches the requirement;

as shown in fig. 4, the prosthetic finger mechanism 2 includes five finger structures 201, the top end inside each finger structure 201 is fixedly connected with the tightening wire 103, each finger structure 201 includes a plurality of segmented structures 2011, the segmented structures 2011 are connected with each other through a shaft to simulate a finger joint, and a first pressure sensor 2012 and a thermistor 2013 are arranged inside the segmented structures 2011; the first pressure sensor 2012 is connected with the external air bag mechanism 3 through an electric signal, and the thermistor 2013 is connected with the heating body 106 through an electric signal; an anti-skid silica gel 2015 is arranged outside the first pressure sensor 2012 and the thermistor 2013;

in the embodiment of the present invention, the first pressure sensor 2012 and the second pressure sensor 303 both adopt flexible film pressure sensors, specifically: the force-sensitive pressure acquisition module adopting the FSR has the sensing range of 20 g-6 kg, and the pressure can correspond to the resistance value; the film pressure sensor is composed of a conducting wire, an external insulation adhesive film and a conducting layer, when the pressure of the conducting coil is tightly pressed with the conducting layer, the resistance value is reduced, the test result is shown in figure 5, the horizontal axis is a pressure value, and the vertical axis is the impedance of the pressure acquisition module. The chip can correspond the pressure resistance value with the voltage value that tests, then reachs the pressure value size.

In the embodiment of the invention, the thermistor 2013 is a thin-film thermistor, and the temperature acquisition speed is high when the temperature sensor is selected. And in the flexible field, the Bertran TTF-103 patch film thermistor is suitable and is mini in size, and in actual use, due to the small volume, the thermistor is not obvious and can respond to the situation of absorbing less temperature to obtain the actual temperature. In order to achieve high temperature precision, the resistance value of the temperature sensor adopted by the invention can change at every 1 ℃ along with the temperature change, and the corresponding temperature can be read through AD conversion in the circuit;

in the embodiment of the invention, the silica gel 2015 is additionally arranged on all finger surfaces contacting with an object, so that the antiskid function can be achieved; the fingers adopt a multi-joint structure, so that the action is more flexible, and the reliability of grabbing objects is ensured. Pressure and temperature sensors are arranged on finger surfaces, and the force of actions such as object grabbing and hand shaking can be ensured through the pressure sensors; the temperature sensor can sense the temperature of the contact object.

As shown in fig. 6, the external airbag mechanism 3 is disposed on the outer side of the hand or arm of the user, and includes an airbag 301, an inflator 302 and a second pressure sensor 303, the inflator 302 is connected to the airbag 301 through a pipeline, and the second pressure sensor 303 is disposed on the contact surface of the airbag 301 and the human body.

In the embodiment of the invention, the air bag 301 adopts an air bag structure similar to that in a sphygmomanometer, but adopts a mini air bag, and the air pumping speed is improved and the pressure feedback is quicker by adjusting the power of the inflating pump 302;

the invention also provides a control method which adopts the bionic mechanical artificial limb;

in a second preferred embodiment of the present invention, as shown in fig. 7, the present invention comprises:

s101, collecting electric muscle signals of an arm of a user, processing the electric muscle signals, sending control signals to a motor, and controlling the motor to rotate so as to drive grabbing and relaxing of a prosthetic finger;

in the embodiment of the invention, the system adopts an Arduino system to carry out analysis processing, and the processed data form a waveform; the test method comprises the following steps: the electromyographic signal acquisition points are arranged on the flexor hallucis longus and comprise two acquisition points which are distributed on the left side and the right side of the arm, the muscle on the right side is mainly used for measuring the four fingers, and the muscle on the left side is actually mainly used for measuring the thumb. The hand-gripping dynamometer simultaneously records the number of the data gripping strength cattle by using different gripping strengths, and obtains the relation between the muscle electrical signal and the number of the gripping strength cattle through comparison of a large amount of experimental data;

s102, collecting pressure signals of the inner side contact surface of the artificial limb finger mechanism and pressure signals of the contact surface of the air bag and a human body, and controlling the inflator pump by judging and comparing the pressure signals in real time;

as shown in fig. 8, specifically:

s1021, acquiring the pressure of the manipulator;

s1022, detecting the pressure between the air bag and the hand;

s1023, judging whether the pressure signal of the inner side contact surface of the artificial limb finger mechanism is larger than the pressure signal of the contact surface of the air bag and the human body, if so, controlling the inflator pump to inflate the air bag and feeding back to execute the step S1021; otherwise, the operation of the inflator is stopped.

S103, collecting a temperature signal of the inner side contact surface of the artificial limb finger mechanism, and controlling a heating element to heat through real-time judgment and comparison with the temperature signal of the heating element;

as shown in fig. 9, specifically:

s1031, obtaining the surface temperature of the artificial limb;

s1032, detecting the surface temperature of the human body;

s1033, judging whether the temperature signal of the inner side contact surface of the artificial limb finger mechanism is larger than the temperature signal of the heating element, if so, controlling the heating element to continue heating; otherwise, the operation of the heating element is stopped.

The invention realizes the identification of muscle electric signals of a human body, the judgment of the action state expected by the human body and the realization of the synchronous action of the artificial limb printed by 3D by utilizing the muscle electric signal acquisition module and the 3D printing technology, and has a protection system for preventing the grip force from being overlarge.

The invention adds a pressure signal acquisition module on the surface of the artificial limb to acquire the surface pressure of the artificial limb, and then adds a pressure feedback device on the hand of a person, so that the device generates corresponding pressure, and the person can know the pressure so as to make corresponding feedback.

The invention adds a temperature signal acquisition module on the surface of the artificial limb to acquire the surface temperature of the artificial limb, and then adds a temperature feedback device on the hand of a person, so that the device generates corresponding temperature to make the person know the temperature. Meanwhile, a temperature heating module is added on the prosthetic limb to synchronize the temperature of the human body, so that the prosthetic limb which can be sensed by the opposite party is not cold ice but has the temperature.

The invention compares and analyzes the myoelectric signal and the hand movement through experiments, confirms that the inevitable relationship exists between the myoelectric signal and the hand movement, finds that the grip strength and the waveform strength have a direct proportion relationship by analyzing the waveform characteristics of the electric signal, and can control the mechanical structure by extracting the waveform signal and controlling the mechanical structure by the waveform signal, thereby achieving the purpose of controlling the movement of the manipulator. In the test process, a user can hold and take the stainless steel water cup, 500ml of bottled water and the ceramic water cup through muscle electric signal control, and the action requirements of the user in the water drinking process can be met. The invention also tests the handshake with a person during daily communication, and the temperature on the surface of the artificial limb during the handshake process is not so cold as to be sensed during the contact process even if the weather is slightly cold. The temperature of the hand to be held can also be sensed by the user through the heating device arranged on the hand of the human body. Meanwhile, the opposite side adopts the process of shaking hands with different force, the user can feel the holding power of the opposite side through the artificial limb, and the process of shaking hands is more humanized compared with the traditional artificial limb.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A bionic mechanical artificial limb is characterized by comprising an artificial limb palm shell, an artificial limb finger mechanism, an external air bag mechanism and at least one muscle electric signal sensor; wherein,

the artificial limb finger mechanism comprises a plurality of finger structures, the top end in each finger structure is fixedly connected with the tensioning line, each finger structure comprises a plurality of segmented structures, the segmented structures are connected through shafts to simulate finger joints, and at least one first pressure sensor and a thermistor are arranged on the inner side of each segmented structure; the first pressure sensor is connected with the external air bag mechanism through an electric signal, and the thermistor is connected with the heating body through an electric signal;

2. The biomimetic mechanical prosthetic of claim 1, wherein a cushioning mechanism is further disposed within the palm shell of the prosthetic.

3. The biomimetic mechanical prosthetic of claim 2, wherein the cushioning mechanism is specifically: and the springs are connected with the tensioning lines in the finger structures.

4. The biomimetic mechanical prosthetic of claim 1, wherein the first pressure sensor and the second pressure sensor are both flexible membrane pressure sensors; the thermistor adopts a thin film thermistor; the heating body adopts a flexible heating film.

5. The biomimetic mechanical prosthetic of claim 1, wherein the first pressure sensor and the thermistor are provided with anti-slip silicone on the outside.

6. The biomimetic mechanical prosthetic of claim 1, wherein the at least one muscle electrical signal sensor, in particular a flexor hallucis longus muscle, disposed on an arm of the user, is configured to collect electrical signals from a thumb and four fingers, respectively.

7. A control method using the biomimetic mechanical prosthetic of claim 1, comprising:

8. The control method according to claim 7, wherein the step of collecting the pressure signal of the inner side contact surface of the artificial limb finger mechanism and the pressure signal of the contact surface of the air bag and the human body, and comparing the pressure signals by real-time judgment to control the inflator pump comprises the following steps:

9. The control method according to claim 7, wherein the collecting of the temperature signal of the inner side contact surface of the artificial limb finger mechanism and the real-time judgment and comparison with the temperature signal of the heating element are used for controlling the heating element to heat, and the method specifically comprises the following steps: