TWI885626B - Sensing system for muscle movement behavior - Google Patents

Abstract

The present invention relates to a sensing system for muscle movement behavior. The system contains a wearable unit and an electronic device. The wearable unit at least contains a wraparound band, which has a control unit and a detection unit. The detection unit is used to detect force deformation data generated by muscle movement of a testing subject, and transmit the data to the electronic device through the control unit. The electronic device has a built-in muscle sensing application. The application sets a default pressure value or/and a default shearing force value after the wraparound band contacts with the muscle and determines the movement behavior of the muscles based on the detected pressure value and the detected shear force value of the force deformation data.

Description

Muscle movement behavior sensing system

The present invention relates to a muscle movement behavior sensing system, in particular, a muscle movement behavior sensing system that detects muscle performance in a motion state through a wearable device.

The non-invasive assessment of general muscle contraction has a wide range of applications in the diagnosis of neuromuscular diseases, muscle fatigue analysis, and control of prosthetic limbs. The non-invasive assessment of muscle contraction can measure contraction by monitoring the electrical or mechanical activity of the muscle.

Surface electromyography (sEMG) is the most commonly used technique to quantify subcutaneous muscle electrical activity. Its advantages are as follows:

(1) Electromyographic measurements of voluntary muscle contractions are widely used in active prosthetic control and other human-machine interfaces (HMIs) because of their intuitiveness.

(2) Surface EMG involves the use of myoelectric electrodes, which can provide a rough assessment of subcutaneous EMG signals and obtain amplified and filtered signals directly from the electrodes through appropriate pre-processing circuits.

(3) Correct measurement of EMG signals involves correct placement of electrodes and good electrical interaction with the skin.

(4) Conductive gel electrodes can achieve good and stable electrical contact with the skin, but for long-term applications, dry electrodes are preferred.

However, the disadvantages of surface electromyography are as follows:

(1) Dry electrodes provide high electrode-skin impedance, but are also susceptible to motion artifacts.

(2) The quality of EMG signals depends on the anatomy and physiology of the muscle-skin interface and the signal conditioning circuitry of the detection unit.

(3) In addition, the acquisition of electromyographic signals is very sensitive to various noise sources, such as inherent noise, motion artifacts, electromagnetic noise, and crosstalk. Although these noises can be minimized to a large extent using appropriate pre-processing circuits, post-processing techniques, and effective training programs, they cannot be eliminated.

Additionally, muscle activity can be monitored by detecting changes in mechanical characteristics during contraction, which results in muscle shortening, changes in cross-sectional area, increased toughness, and also enhanced mechanical vibrations associated with the muscle.

Among them, mechanomyography (MMG), optomyography (OMG) and force myography (FMG) are some measurement techniques used to identify the mechanical changes that occur during muscle contraction, while MMG is measured through the mechanical vibrations generated during muscle activation. This method is considered to be the mechanical equivalent of EMG signals. In addition, there is bioimpedance or electrical impedance myography (EIM).

Accelerometers, piezoelectric inductors, microphones, and laser distance sensors are various types of sensors used to evaluate MMG signals. In some case studies, MMG signals have been used to analyze muscle function, prosthetic control, identify neuromuscular diseases, and muscle assessment during sports and medicine. Compared to EMG, MMG has several advantages, such as simple acquisition settings, high signal-to-noise ratio (SNR), and immunity to external electromagnetic interference. However, compared to EMG signals, it is more sensitive to motion artifacts, which can significantly affect the results.

OMG is another new method that utilizes photoelectric sensors to detect mechanical changes in muscles during contraction and provides a higher signal-to-noise ratio and enhanced robustness to address the undesirable characteristics and limitations of MMG and EMG.

OMG provides a low-cost, non-contact assessment of muscle contraction that can be effectively used to generate control signals for upper limb prostheses and other rehabilitation applications, but OMG signals are more susceptible to motion artifacts than EMG and also exhibit slight latency, which may affect performance in real-time control applications.

FMG is a recently developed technology that uses force-sensitive resistors (FSRs) to record changes in muscle volume during activity. Unlike EMG, FMG is inexpensive, simple to use, insensitive to external electrical interference, and does not require the use of electrodes and complex conditioning circuits.

Additionally, FMG produces more reproducible patterns and shows greater overall stability over time compared to EMG, and FMG provides an assessment of muscle contraction that can be effectively used to generate control signals for upper limb prostheses and other rehabilitation applications.

In recent applications, FMG-based control systems have attracted attention for use in prosthetic devices. The overall application cost of the FMG system is lower because it requires fewer FSRs compared to the EMG system, which involves a large number of electrodes to detect different gestures of muscle activity.

However, previous studies have reported that using FSR directly on the skin may only provide qualitative information about muscle activation. Simple FSR elements cannot provide quantitative details, such as the relationship between FSR output and contraction strength and comparative analysis with other sensors. FSR can only provide basic information about muscle activation and relaxation.

In addition, using a basic voltage divider as the FSR's adjustment circuit will produce nonlinearity, large drift errors, and sensitivity variations within its operating range. These errors and nonlinearities can be minimized by using appropriate electronic adjustment circuits and signal processing systems.

The above-mentioned knowledge technologies (EMG, MMG, OMG, FMG) have their own advantages and disadvantages, but they generally lack the ability to identify the types of muscle movements (such as axial rotation of muscles, and muscle extension or tension and pressure in all directions, even quantitatively). This may require FMG to have three-dimensional force measurement or three-dimensional deformation measurement, that is, pressure and shear force measurement.

Therefore, in order to achieve the ability to measure muscle axial rotation, muscle extension or tension and pressure in all directions, quantitative and other muscle performance, this case uses a wearable device with a sensor element to perform measurements to determine the movement behavior of the muscles in that part of the body. In this way, the present invention should be the best solution.

The muscle movement behavior sensing system of the present invention comprises a wearable body, which at least comprises a wraparound belt body, the belt body has a control unit, which has a first flexible circuit board, the first flexible circuit board has at least a microprocessor and a wireless transmission module electrically connected to the microprocessor, the microprocessor is used to transmit a force deformation data through the wireless transmission module, wherein the force deformation data at least comprises a detection pressure value and a detection shear force value; a detection unit, which is electrically connected to a second flexible circuit board, the second flexible circuit board is further electrically connected to the first flexible circuit board, wherein each detection unit is located toward a muscle of a body part, the detection unit The belt has at least one elastic body and one sensing element. The elastic body is wrapped around the sensing element. The sensing element is used to detect and obtain the force deformation data of the elastic body being squeezed by the muscles of the body part, and transmit the force deformation data to the flexible circuit board; and an electronic device is connected to the control unit of the belt body to receive the force deformation data. The electronic device has a built-in muscle sensing application. After the muscles of the body part come into contact with the belt body, the muscle sensing application can set a preset pressure value or/and a preset shear force value, and judge the movement behavior of the muscles of the body part according to the detected pressure value and the detected shear force value of the force deformation data.

More specifically, after the muscle of the body part contacts the belt, the muscle squeezes the elastic body of the detection unit, so that the sensing element detects the force deformation data generated by the deformation of the elastic body.

More specifically, the sensing element is a piezoresistive sensor, an optical sensor or a magnetic sensor.

More specifically, the elastic body is silicone or rubber.

More specifically, the wireless transmission module is capable of transmitting the force deformation data to the electronic device using a Bluetooth transmission technology or a WIFI technology.

More specifically, the control unit further includes a multi-axis inertia measuring element electrically connected to the microprocessor, and the multi-axis inertia measuring element is used to measure a movement trajectory data, a muscle rotation data, and a muscle contraction data of the muscle of the body part in contact with the belt.

More specifically, the second flexible circuit board further includes a multi-axis inertial measurement element, which is used to measure a movement trajectory data, a muscle rotation data, and a muscle contraction data of the muscle of the body part in contact with the belt.

More specifically, the movement of the muscles of the body part is muscle contraction, muscle relaxation, muscle rotation and/or muscle stretching.

More specifically, the belt body has an outer ring portion and an inner ring portion, the outer ring portion is made of a tough material that cannot be lengthened or shortened, the inner ring portion is made of a soft material, and the control unit and the detection unit are sandwiched between the outer ring portion and the inner ring portion.

More specifically, the belt body has one or more airbags located inside the detection unit, and an inflation unit is connected to the airbag, and the inflation unit is electrically connected to the control unit, and the control unit is used to control the inflation or deflation of the airbag, so that the preset pressure value and/or the preset shear force value can be generated after the muscles of the body part come into contact with the belt body.

1: With body

11: Outer Ring Department

12: Inner ring

13: Control unit

131: First flexible circuit board

1311: Microprocessor

1312: Wireless transmission module

1313:Multi-axis inertial measuring element

14: Detection unit

140: Second flexible circuit board

141: Elastic body

1411: Magnetic components

142:Sensing element

151: First joint

152: Second joint

2: Electronic devices

21: Processor

22: Computer-readable recording media

221: Muscle Sensing App

31: Biceps

32: Triceps

401~416: Detection unit

42: Control unit

5: vest

51: Body

52: Body

53: Body

6: Shorts

[Figure 1] is a schematic diagram of the belt structure of the muscle movement behavior sensing system of the present invention.

[Figure 2A] is a schematic diagram of the overall connection of the muscle movement behavior sensing system of the present invention.

[Figure 2B] is a schematic diagram of the structure of the first flexible circuit board of the muscle movement behavior sensing system of the present invention.

[Figure 2C] is a schematic diagram of the structure of the detection unit and the second flexible circuit board of the muscle movement behavior sensing system of the present invention.

[Figure 3] is a schematic diagram of the structure of the detection unit of the muscle movement behavior sensing system of the present invention.

[Figure 4] is a schematic diagram of the electronic device structure of the muscle movement behavior sensing system of the present invention.

[Figure 5A] is a schematic diagram of the arm raising state of the muscle movement behavior sensing system of the present invention.

[Figure 5B] is a schematic diagram of the muscle movement behavior sensing system of the present invention when the arm is stretched straight.

[Figure 6A] is a schematic diagram of the first force state of the detection unit of the muscle movement behavior sensing system of the present invention.

[Figure 6B] is a schematic diagram of the second force state of the detection unit of the muscle movement behavior sensing system of the present invention.

[Figure 6C] is a schematic diagram of the third force state of the detection unit of the muscle movement behavior sensing system of the present invention.

[Figure 7A] is a schematic diagram of the detection unit of the muscle movement behavior sensing system of the present invention being applied to the wearing of a vest.

[Figure 7B] is a schematic diagram of the detection unit of the muscle movement behavior sensing system of the present invention being applied to the buttocks.

[Figure 8] is a schematic diagram of the whole body wearable detection unit of the muscle movement behavior sensing system of the present invention.

[Figure 9] is a schematic diagram showing the test comparison of the superficial flexor digitorum muscle of the muscle movement behavior sensing system of the present invention.

[Figure 10] is a schematic diagram of the force changes of different lifting movements of the muscle movement behavior sensing system of the present invention.

Other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the preferred embodiment with reference to the drawings.

The muscle movement behavior sensing system of the present invention includes a wearable body and an electronic device. The wearable body includes at least a wraparound belt (or a wearable body composed of multiple belts). The belt 1 is shown in Figure 1. The belt 1 has an outer ring portion 11, an inner ring portion 12, a control unit 13 and a detection unit 14.

The outer ring portion 11 is made of a tough material that cannot be lengthened or shortened. The outer ring portion 11 is bendable, but cannot be lengthened or shortened in the long axis direction.

The inner ring portion 12 is made of a soft material.

A control unit 13 and one or more detection units 14 are disposed between the outer ring portion 11 and the inner ring portion 12.

The outer ring portion 11 is provided with a first coupling portion 151 and a second coupling portion 152. The first coupling portion 151 and the second coupling portion 152 can be coupled to each other so that the belt body 1 is wrapped around and fixed on a body part.

The first joint portion 151 and the second joint portion 152 can be made of Velcro material.

As shown in FIG. 2A, the control unit 13 is wirelessly connected to the electronic device 2, and the control unit 13 is wired or wirelessly connected to the detection unit 14.

As shown in FIG. 2B , the control unit 13 has a first flexible circuit board 131, and the first flexible circuit board 131 has at least a microprocessor 1311 (e.g., Nordic 52840), a wireless transmission module 1312 electrically connected to the microprocessor 1311, and a multi-axis inertial measurement element 1313 (e.g., ICM20948) electrically connected to the microprocessor 1311.

The microprocessor 1311 is used to transmit a force deformation data through the wireless transmission module 1312, wherein the force deformation data at least includes a detection pressure value and a detection shear force value.

The wireless transmission module 1312 is capable of transmitting the force deformation data to the electronic device 2 using a Bluetooth transmission technology or a WIFI technology.

The multi-axis inertia measuring element 1313 is used to measure a movement trajectory data, a muscle rotation data and a muscle contraction data of the muscle of the body part in contact with the belt 1.

As shown in FIG. 2C and FIG. 3, the detection unit 14 is disposed on a second flexible circuit board 140 (where each detection unit 14 is located toward a muscle of a body part), and the second flexible circuit board 140 and the first flexible circuit board 131 can be connected via a flat cable or a wire with a signal transmission function, so that the data detected by the detection unit 14 can be transmitted to the first flexible circuit board 131.

In addition to wired connection, the second flexible circuit board 140 can also have wireless transmission function, so the force deformation data sensed by the detection unit 14 can be transmitted using wireless transmission technology.

The second flexible circuit board 140 is provided with a multi-axis inertia measurement element 1313 (such as ICM20948), so that the motion trajectory data, muscle rotation data, and muscle contraction data can be transmitted through wireless transmission technology.

The first flexible circuit board 131 and the second flexible circuit board 140 can be the same circuit board or different circuit boards.

The detection unit 14 has at least an elastic body 141 and a sensing element 142. The elastic body 141 is wrapped around the sensing element 142. The elastic body 141 has a magnetic element 1411 (the magnetic element 1411 is, for example, a magnet) inside. The sensing element 142 is used to detect and obtain the force deformation data of the elastic body 141 being squeezed by the muscles of the body part, and transmit the force deformation data to the first flexible circuit board 131.

The elastic body 141 is made of silicone or rubber. The elastic body 141 can transmit the force deformation to the sensing element 142. The elastic body 141 can be designed with a gap inside.

When the muscle of the body part contacts the belt 1, the muscle squeezes the elastic body 141 of the detection unit 14, so that the sensing element 142 detects the force deformation data generated by the deformation of the elastic body 141.

The sensing element 142 is a 3D force sensor, and its element type can be a piezoresistive sensor, a capacitive sensor, a piezoelectric sensor, an optical sensor, or a magnetic sensor (three-axis magnetic sensor, such as MLX90393).

If a three-axis magnetic sensor is used, the force deformation data detected is magnetic displacement data. Afterwards, when it is transmitted to the microprocessor 1311 or the electronic device 2, the magnetic displacement data can be converted into three-axis force information (pressure value, shear force value).

For the three-axis magnetic sensor, further explanation is as follows:

(1) The value read by the three-axis magnetic sensor is the magnetic flux density (magnetic flux density is equal to magnetic flux divided by unit area). When the magnetic element 1411 (magnet) and the sensing element 142 (three-axis magnetic sensor) are close to each other, the magnetic flux increases and the magnetic flux density also increases.

(2) The magnetic flux generated by the magnet is from low to high. By applying forces in different directions to the elastic body 141 (silicone rubber), magnetic fluxes in different axial directions will be generated by the magnet. By applying forces in different directions to the silicone rubber, magnetic fluxes in different axial directions will generate different magnetic flux densities.

The three-axis magnetic sensor can read the three-axis magnetic flux and convert it into the compressive shear force on the three-axis magnetic sensor. The communication between the three-axis magnetic sensor and the microprocessor uses an integrated bus circuit (I2C) or SPI interface for communication.

In some embodiments, multiple three-axis magnetic sensors (e.g., 16 or 31) require at least one 16-to-1 multiplexer between the three-axis magnetic sensors and the microprocessor.

The electronic device 2 is connected to the control unit 13 to receive the force deformation data. As shown in FIG. 4, the electronic device 2 includes at least one processor 21 and at least one computer-readable recording medium 22. The computer-readable recording medium 22 stores at least one muscle sensing application 221. The computer-readable recording medium 22 further stores computer-readable instructions. When the processor 21 executes the instructions, the muscle sensing application 221 is executed. When the computers can read the instructions, when the muscles of the body part come into contact with the belt 1, the muscle sensing application 221 can set a preset pressure value or/and a preset shear force value, and judge the movement behavior of the muscles of the body part according to the detected pressure value and the detected shear force value of the force deformation data. The movement behavior of the muscles of the body part is muscle contraction movement, muscle relaxation movement, muscle rotation movement or/and muscle extension movement.

When the muscles of the body part contract, the first muscle group measures positive pressure and shear force, and the second muscle group relative to the first muscle group measures negative pressure and shear force.

When the muscles of the body part produce relaxation movement, the first muscle group measures negative pressure and shear force, and the second muscle group relative to the first muscle group measures positive pressure and shear force.

When the muscle groups in that body part rotate and stretch, the changes in compression/shear forces can also be measured.

The electronic device 2 is a laptop computer, a desktop computer, a tablet computer or a server device.

As shown in Figure 1, the wearable device of the present invention can be a 3D force/IMU ring. The band 1 (ring) includes at least four sensing elements 142 (3D force sensors) and at least one control unit 13 (including a microprocessor 1311, a wireless transmission module 1312, and a multi-axis inertia measurement element 1313 (IMU, such as BMX160 or MPU9250). The sensing element 142 can effectively detect the force of the muscle group at the required measurement position and can quantify the extent of progress. And because it outputs 12 signals, it is particularly helpful to judge the effect of rehabilitation and various types of sports.

When you want to know whether the strength provided by the limbs is sufficient, whether the muscle groups used are correct, and whether the correct output and training are used during fitness, if the power of hitting the ball or jumping is insufficient, you need to train specifically. By wearing the belt 1 of the present invention on the muscle parts that need to be strengthened, you can close the loop to know the output and endurance of the muscle parts.

When the belt 1 is wrapped around or worn on the muscle to be tested of one of the limbs, and corresponding numbers of sensing elements 142 are provided according to different body parts, when used, the belt 1 is tightened with the body part to generate a set preload.

When the strap 1 is tightened to the body part, as shown in FIG. 5A , the biceps 31 generates positive pressure (first preset pressure value), the triceps 32 generates negative pressure (second preset pressure value) and a first preset shear force value.

After performing the action shown in Figure 5B, as shown in Figure 6A, the biceps 31 generates negative pressure (first detection pressure value) and the triceps 32 generates positive pressure (second detection pressure value). It can be seen that the muscle pressure changes caused by the change of action can be detected.

After the movement from Figure 5A to Figure 5B, as shown in Figure 6B, the arm axial shear force (the first detected shear force value) will be generated. It can be seen that the muscle shear force changes caused by the change of movement can be detected.

As shown in Figure 6C, when the arm rotates around the X axis, a lateral Y shear force (the second detected shear force value) will be generated.

From the above, it can be seen that the changes in the three-axis measurement values of the sensing element 142 of the present invention can detect the movement direction and force size and direction of the contacted muscle, which is something that cannot be achieved by various technologies known in the past for measuring muscle movement.

As shown in FIG. 7A, multiple straps 51, 52, 53 can be worn on the upper body (including the chest muscle group and the back shoulder muscle group) and use the style of a vest 5. As shown in the figure, the outer part of the vest uses a fabric that can be bent but cannot be stretched and contracted as a base material, and the inner part of the vest is a fabric that can be attached with Velcro. The 3D force sensor can be combined with a Bluetooth transmission module to form an independent device, and its bottom surface has Velcro, so it can be attached to the position inside the vest according to the muscle to be measured. Therefore, after attaching multiple 3D force sensors, the vest can be put on and the degree of tightening can be adjusted to generate the required preload.

In some embodiments, for the lower torso, including the muscle groups of the hip joint and the waist, shorts 6 can be used, as shown in Figure 7B. The outer part of the shorts uses a flexible but non-stretchable and non-contractable fabric as the base material, and the inner part of the shorts is a Velcro-attached fabric. The 3D force sensor can be combined with a Bluetooth transmission module to form an independent device, and the bottom surface of the device has Velcro, so it can be attached to the position inside the shorts according to the muscle to be measured. Therefore, after attaching multiple 3D force sensors, the shorts can be put on and the degree of tightening can be adjusted to generate the required preload.

As shown in FIG. 8, in an embodiment of the present invention, the multiple detection units 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416 of the belt can be in the form of a sensing ring, which can be worn on the user's head, limbs, waist and chest (around the front and back) to detect the muscles of the upper arm, lower arm, thigh muscles (semitendinosus, biceps femoris), calf muscles (such as tibialis anterior, soleus), chest muscles (pectoralis major), back muscles, shoulder muscles (trapezius), waist muscles, gluteus maximus, etc.

The detection units 401~416 of the belt body are connected to the control unit 42 via Bluetooth wireless connection or electrical connection line to transmit the detection data to the control unit 42.

This case can test the "flexor digitorum superficialis" of the right forearm. The testing steps are as follows:

(1) Place the arm on a flat surface for a certain period of time (e.g. 5 seconds) to obtain a preset pressure value and/or a preset shear force value.

(2) Lift a weight (e.g. 2 kg), raise it to a certain height (e.g. 10 cm) and hold it there for a certain time (e.g. 5 seconds).

(3) Put the weight down and place your arm on a flat surface again for a certain period of time (e.g. 5 seconds).

(4) Lift the weight again to a certain height (e.g. 10 cm) and hold it for a certain time (e.g. 2.5 seconds).

(5) After putting it down for a certain time (e.g. 1 second), lift it up again and hold it for a certain time (e.g. 2.5 seconds).

(6) The above process is repeated a certain number of times (e.g. 5 times) when the sensing element is obstructed, and the average is obtained to obtain a comparison chart such as Figure 9. It can be seen from the figure that the data obtained is obviously not affected regardless of whether there is an obstruction or not.

This case can be applied to exoskeletons. It is generally known that exoskeletons often use sEMG to detect force intentions. However, its disadvantage is that the sensing electrode patch needs to be in close contact with the skin of the force-generating muscles. This is very impractical for users who are fully clothed, because relying solely on sensors such as IMU to detect angle changes between limbs and trunks or adding torque sensors to mechanisms or motors still cannot determine the user's intentions in advance.

Therefore, through the wearable device of this case, a sensitive 3D force sensor is used with IMU integration to more accurately detect the intention and posture of exertion, and the contraction of muscles is used to generate thrust, causing the elastic body to produce pressure changes, and then the pressure changes are used to judge whether the thigh muscles are exerting force.

This case uses a compressive shear force sensor instead of an airbag to detect whether the muscles are exerting force. The probe on the device measures the current muscle force state and provides lateral force to determine the force applied by the exoskeleton device to the human body.

The detection unit can be placed on the limbs and abdomen of the human body, and the different parts are described as follows:

(1) The position of the arm can use the contraction of the arm muscles to detect whether the wearer is lifting heavy objects.

(2) The abdominal muscles play a very important role in the mobility and stability of the lumbar spine, regardless of the speed, direction and load status of the movement.

(3) The abdominal muscles should begin to contract before the upper limbs move, and the detection unit can be used to detect the wearer's movement status.

(4) The position of the thigh can detect whether the thigh muscles contract during the process of the wearer bending down to lift a heavy object and standing up to help the wearer complete these two movements.

For lifting heavy objects and bending over and standing up, since the detection unit is located in the abdomen for measurement, When bending over, the abdominal muscles contract to support the upper body and maintain the stability of the body, and the pressure value measured by the sensor gradually increases, and then gradually decreases when standing up. This will be able to detect changes in waist pressure. With Figure 10, an example is given as follows:

(1) Because pre-calibration is required before testing, when the angle of the IMU (multi-axis inertial measurement unit) is 0 (judged to be in a standing position).

(2) After that, the first action is to make a 90° bend without lifting any object. Since no object is lifted, it can be observed that the angle of the back IMU sensor rises to 90°, while the waveform of MLX (sensing element, a magnetic sensor is used in this embodiment) does not change.

(3) After returning to the standing position, the IMU angle returns to 0°.

(4) Afterwards, in the second movement (second bend), the tester lifted a weight of a certain weight. At this time, we can observe that the force change of the IMU has a significant upward trend, and the angle of the IMU is also 90°.

(5) The third movement (third bend) is to lower the weight, the fourth movement (fourth bend) and the fifth movement (fifth bend) are the same as the first movement, and the fourth and fifth movements are the same as the second and third movements.

(6) Since this embodiment uses a three-axis magnetic sensor and a multi-axis inertial measurement element, the Z axis of the three-axis magnetic sensor can be used to determine the state characteristics of bending to 90 degrees, and the multi-axis inertial measurement element can be used to measure torque, angle and speed to analyze motion trajectory data, muscle rotation data, and muscle contraction data.

The circuit design of the 3D force sensor and IMU developed in this project allows the circuit board to be integrated with the exoskeleton strap, which has the following advantages:

(1) The strap is used to fix the exoskeleton to the limbs or trunk of the body. The fixing force needs to be standardized. The 3D force sensor can be used as a basis for adjusting the tightness.

(2) If the standard force of tightening is reached, it can be used as a benchmark point for the corresponding muscle not exerting force. In this way, once the muscle exerts force, it can be easily detected, and the differences between different users can be covered.

(3) The built-in IMU can simultaneously detect the movement posture and angle of the limb, which serves as the basis for the exoskeleton to provide assistance.

(4) These sensor data can be provided to the controller via Bluetooth or wired for enhanced learning or deep learning, which can effectively bring more accurate and customized personal exoskeleton robots.

The belt in this case has the following implementation forms, for example:

(1) Use a three-dimensional force sensor array, IMU, body surface impedance circuit, and sweat-wicking fabric, where the body surface impedance circuit can use AD5933.

(2) Use a three-dimensional force sensor array, IMU, surface impedance circuit, and sweat-wicking fabric, and a low-frequency generator for low-frequency therapy. Low-frequency transcutaneous stimulation can relieve acid fatigue, and its therapeutic effect can be intelligently adjusted through sEMG sensing feedback to adjust the intensity and frequency waveform of the low frequency.

(3) Use a three-dimensional force sensor array, IMU, body surface impedance circuit, and sweat-wicking fabric, and combine it with heart rate or body temperature sensors. The heart rate sensor data can be used to infer emotions.

(4) Use a three-dimensional force sensor array, IMU, body surface impedance circuit, and sweat-wicking fabric, combined with heart rate and body temperature sensors or transdermal patches.

(5) Use batteries, Bluetooth components (BLE), multi-axis inertial measurement units (IMU), body surface impedance circuits, heart rate processing circuits, and low-frequency generators to form a replaceable module.

The technology in this case can be used for the control signal of active prosthetic devices, as explained below:

(1) The technology in this case can be used to detect muscle contraction used to control hand prostheses.

(2) The detection unit is designed with a pair of FSR elements installed in the chassis of the prosthetic device, and the chassis receives muscle contraction force through a hemispherical elastic body coupler composed of PDMS. The detection unit also includes a specific regulation circuit with an appropriate power supply to generate a voltage output proportional to the contraction strength.

(3) Since the detection unit is simple, compact, sensitive, and easy to install on the amputee's stump, it can reliably capture the mechanical activity of the muscles.

(4) The detection unit generates an output signal that is equivalent to the linear response of the electromyogram. The detection data of the detection unit is used to control the prosthetic device and perform the grasping operation using a proportional scheme. Compared with traditional electromyography sensors, this technology can provide smoother and faster operation for the prosthetic device.

The technology in this case can be used to prevent muscle injuries related to sports training, as explained below:

(1) Through the analysis of golf movements, it is found that the downswing movement is the key to causing elbow injuries in golf.

(2) The time when the leading arm (non-dominant hand) extensor muscles of professional players exert the greatest force is in the early stage of the downswing, while for amateur players it is from the late stage of the downswing to the moment of impact.

(3) From the above explanation, we can see that amateur players tend to rely on arm strength to accelerate the swing in order to generate faster swing speed and explosive power, while professional players are more capable of using trunk rotation to generate power.

(4) Therefore, through the technology of this case, it will be possible to more clearly understand the swing muscle performance of professional players, and through analysis, fine-tune the swing action to avoid sports injuries.

The belt body further includes one or more airbags, which are located inside the detection unit, and an inflation unit is connected to the airbag, and the inflation unit is electrically connected to the control unit. The control unit is used to control the inflation or deflation of the airbag, so that the preset pressure value and/or the preset shear force value can be generated after the muscles of the body part come into contact with the belt body.

An airbag can be installed at any position between the outer ring and the inner ring, and the airbag can be inflated or deflated by the inflation unit. Inflation or deflation is based on whether the measurement value of the detection unit reaches the preset target starting value (preset pressure value or/and the preset shear force value).

The inflation unit includes an air pressure pump and an air valve. The control unit receives the pressure feedback value from the detection unit and outputs a command to the air pressure pump to achieve the preset target starting value. Different preset target starting values can be designed for each part of the belt.

Basically, when wearing it, the muscles should remain relaxed and in this state, inflate to reach the preset target starting value (preset pressure value and/or the preset shear force value), and then the air valve can be closed to keep the airbag at a fixed inflation pressure. The user can then perform various muscle exercises and measure the output of the muscles at each point.

The muscle movement behavior sensing system provided by the present invention has the following advantages when compared with other commonly used technologies:

(1) This case can measure muscle axial rotation, muscle extension or tension and pressure in all directions, quantitative and other muscle performances. This case uses a wearable device with a sensor element for measurement to determine the movement behavior of the muscles in that part of the body.

(2) This case can simultaneously monitor and prevent sports injuries, and can target specific muscles for fitness, identify whether rehabilitation movements are appropriate, analyze the posture of athletes in sports competitions, and treat and administer medication to aging cells in various joints of the body.

(3) This case can also detect local fatigue and soreness of the body and provide precise treatment, detect the accuracy of muscle movement, serve as a tool for controlling prosthetic limbs, serve as sensor input for exoskeleton robots, and serve as a tool for professional players to train and detect their stability and physical condition during games.

The present invention has been disclosed through the above-mentioned embodiments, but it is not used to limit the present invention. Anyone familiar with this technical field and having common knowledge can understand the above-mentioned technical features and embodiments of the present invention without making any changes or modifications.

1: With body

11: Outer Ring Department

12: Inner ring

13: Control unit

131: First flexible circuit board

14: Detection unit

140: Second flexible circuit board

Claims (10)

A muscle movement behavior sensing system includes: a wearable body, which at least includes a wraparound belt, the belt having: a control unit, which has a first flexible circuit board, the first flexible circuit board having at least a microprocessor and a wireless transmission module electrically connected to the microprocessor, the microprocessor is used to transmit a force deformation data through the wireless transmission module, wherein the force deformation data at least includes a detection pressure value and a detection shear force value; a detection unit, which is electrically connected to a second flexible circuit board, the second flexible circuit board is further electrically connected to the first flexible circuit board, wherein each detection unit is located toward a muscle of a body part, the detection unit The element has at least one elastic body and one sensing element, the elastic body is wrapped around the sensing element, the sensing element is used to detect and obtain the force deformation data of the elastic body being squeezed by the muscles of the body part, and transmit the force deformation data to the flexible circuit board; and an electronic device is connected to the control unit of the belt body to receive the force deformation data, and the electronic device is built-in with a muscle sensing application program. After the muscles of the body part come into contact with the belt body, the muscle sensing application program can set a preset pressure value or/and a preset shear force value, and judge the movement behavior of the muscles of the body part according to the detected pressure value and the detected shear force value of the force deformation data. As described in claim 1, the muscle movement behavior sensing system, wherein after the muscle of the body part contacts the belt, the muscle squeezes the elastic body of the detection unit, so that the sensing element detects the force deformation data generated by the deformation of the elastic body. A muscle movement behavior sensing system as described in claim 1, wherein the sensing element is a piezoresistive sensor, a capacitive sensor, a piezoelectric sensor, an optical sensor or a magnetic sensor. The muscle movement behavior sensing system as described in claim 1, wherein the elastic body is silicone or rubber. The muscle movement behavior sensing system as described in claim 1, wherein the wireless transmission module is capable of transmitting the force deformation data to the electronic device using a Bluetooth transmission technology or a WIFI technology. The muscle movement behavior sensing system as described in claim 1, wherein the control unit further includes a multi-axis inertia measuring element electrically connected to the microprocessor, and the multi-axis inertia measuring element is used to measure a movement trajectory data, a muscle rotation data, and a muscle contraction data of the muscle of the body part in contact with the belt. The muscle movement behavior sensing system as described in claim 1, wherein the second flexible circuit board further includes a multi-axis inertia measuring element, and the multi-axis inertia measuring element is used to measure a movement trajectory data, a muscle rotation data, and a muscle contraction data of the muscle of the body part in contact with the belt. A muscle movement behavior sensing system as described in claim 1, wherein the movement behavior of the muscle of the body part is muscle contraction movement, muscle relaxation movement, muscle rotation movement or/and muscle extension movement. The muscle movement behavior sensing system as described in claim 1, wherein the belt body has an outer ring portion and an inner ring portion, the outer ring portion is made of a tough material that cannot be lengthened or shortened, the inner ring portion is made of a soft material, and the control unit and the detection unit are sandwiched between the outer ring portion and the inner ring portion. The muscle movement behavior sensing system as described in claim 1, wherein the belt further has one or more airbags, the airbags are located inside the detection unit, and an inflation unit is connected to the airbag, and the inflation unit is electrically connected to the control unit, and the control unit is used to control the inflation or deflation of the airbag, so that the preset pressure value and/or the preset shear force value can be generated after the muscles of the body part come into contact with the belt.

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