TWI603716B - Knee joint torque calculation method - Google Patents

Description

Knee joint torque calculation method

The present invention provides a knee joint torque calculation method, in particular, the wearable device is worn on a preset wearing position of the lower leg, and the acceleration and angular velocity of the calf displacement are detected through the motion sensor to substitute for the knee joint abduction. The method of adduction and average torque, in turn, the abduction, adduction and average torque of the knee joint, to achieve the effect of not being limited by the field and monitoring at any time.

According to the current trend of sports, regardless of gender, ethnicity, ethnicity and all ages, it can promote or maintain cardiopulmonary ability and muscular endurance through normal regular exercise, while promoting metabolic rate, improving immunity, and helping Eliminate psychological stress, improve the quality of life and other benefits, so that individuals have the best physical and mental state.

In addition, the human body has a variety of body and joints, such as knee joints, hip joints, ankle joints or wrist joints, etc., which are extremely important joints for human activities in various activities, such as sitting, walking, running, jumping, going up and down stairs. Movements related to the movement of the human body, such as dance, track and field movements, etc., must be carried out by the rotation or bearing of the body joints. From the point of view of human mechanics, the body and joints must withstand most of the body during movement or movement. The weight of the part, therefore, the body joints are very prone to damage, wear or aging, so whether it is running, basketball, volleyball, football, etc., or walking, going up and down stairs, dance, etc., need to be correct Position to prevent soreness, sports injuries, joint wear or breakage caused by poor posture problem.

Among them, the knee joint in the body joint plays an important role in transmitting and absorbing power in motion or movement. The knee joint belongs to a synovial joint, and the joint between the femur, the tibia and the tibia. The knee joint is structurally a hinge joint (Hinge joint), which is an in-plane moving joint that can move up and down, but cannot move left and right, so the knee joint can only be flexed or stretched theoretically. The movement in a single axial direction, but in actual operation, the knee joint is accompanied by adduction, abduction, and rotation of the other two axial directions of the inner and outer rotations, but sometimes the posture is incorrect due to movement or movement. Or some rotation, turning, etc. to change the direction of motion is too large, resulting in the increase of the other two axial rotation angles. If the rotation angle is too large or abnormal, it will cause acute injury to the knee joint (such as tendon and ligament tissue). Break, etc.) or chronic injury (such as meniscus, cartilage wear or rupture, tendon, ligament tissue inflammation, etc.).

However, in order to prevent the posture during movement or movement from being incorrect, or to change the direction of motion such as rotation or turning, the torque generated by the knee joint during movement or movement, that is, the twisting time, can be measured and observed. The force generated to understand the condition of the joint, as well as the tension, pressure and other information of the muscles, ligaments, tendons, bones and other tissues, can achieve the correct posture through the information obtained, and thus avoid the knee cause some damages.

However, at present, it is necessary to measure the knee joint torque through the laboratory equipment. Generally, the motion capture system and the force plate are used for the measurement operation to obtain the knee joint torque. Knee joint Angle) and ground reaction force (GRF) parameters, and then the obtained parameters are substituted into the inverse kinetics (Inverse kinematics) formula, thereby calculating the knee joint torque, the motion analysis system and the force measurement Instruments such as boards have a certain volume, and require a certain space to be placed for measurement operations, resulting in many restrictions on the field, and can not be measured at any time, thereby causing inconvenience to the user.

Therefore, how to solve the above-mentioned lack of inconvenience and inconvenience is the direction that the relevant industry players in this industry are eager to study and improve.

Therefore, in view of the above-mentioned shortcomings, the inventors have collected relevant information, and through multiple evaluations and considerations, and through years of experience in the industry, through continuous trial and modification, the invention patent for this knee joint torque calculation method was designed. By.

The main purpose of the present invention is to calculate the knee joint torque by wearing the wearing device of the wearing device at the preset wearing position of the user's lower leg, and aligning the motion sensor mounted on the wearing device with the preset wearing. At the position, and connected to the electronic device, when the user starts to move, the acceleration and angular velocity of the calf displacement can be detected through the motion sensor, and the acceleration and the angular velocity are respectively calculated in the three axial directions by the electronic device. The data value and the displacement data are then used to determine the time point of the ground period on the displacement data by using the identification method of the ground period and the swing period, and the data values in the axial directions at the time point of the landing period can be taken out. Then the data value is substituted into the knee joint adduction torque abduction torque and average torque formula to obtain the knee joint outreach, adduction torque and average torque, which can be abducted after wearing the wearing device on the calf. , the adduction torque and the average torque, that is, no need to use another space, it will not be restricted by the use of the field. The user can be monitored at any time to prevent the knee joint from being damaged due to poor posture.

A secondary object of the present invention is that the overall structure of the wearing device is simple and the number of internal electronic components is small, that is, the manufacturing cost is low, and the product competitiveness is improved.

1‧‧‧Wearing device

11‧‧‧ Wearables

12‧‧‧Sports sensor

2‧‧‧ calf

21‧‧‧ wearing position

The first figure is a flow chart of the steps of the present invention.

The second figure is a usage state diagram of the present invention.

The third graph is a plot of angular velocity versus time for the present invention.

The fourth figure is a graph of the three-axis acceleration in the landing time point of the invention.

The fifth graph is a graph of the three-axis angular velocity in the landing time point of the present invention.

In order to achieve the above objects and effects, the technical means, the structure, the method of the implementation, and the like, which are used in the present invention, are described in detail in the preferred embodiments of the present invention.

Please refer to the first, second, third, fourth and fifth figures, which are the flow chart of the steps of the invention, the state diagram of use, the curve of angular velocity versus time, and the curve of the three-axis acceleration at the time of landing. And the graph of the three-axis angular velocity in the time point of the ground, as can be clearly seen from the figure, the calculation method of the knee joint torque of the present invention, especially the calculation of the knee joint abduction moment (Abduction moment), the adduction torque (Adduction moment) and Mean moment method, the steps The sudden is:

(A01) First, the wearing object 11 of the wearing device 1 is worn on the preset wearing position 21 of the user's lower leg 2, and the motion sensor 12 mounted on the wearing object 11 is aligned with the preset of the lower leg 2. The position 21 is worn and the motion sensor 12 is wired to an electronic device having an operational function.

(A02) The user starts moving (slow walking, brisk walking or running, etc.), and uses the motion sensor 12 to detect the acceleration (Acceleration) and angular velocity (Angular velocity) of the calf 2 displacement, and the acceleration is calculated by the electronic device. And the angular velocity is the data value in the three axial directions (X, Y, Z axis), and the displacement data including the acceleration versus time graph or the angular velocity versus time graph.

(A03) Re-use the Stance phase and the Swing phase to determine the displacement data to obtain the time point of the ground period (ie Heel strike to the toes off the ground). (Toe off) time point}.

(A04) After obtaining the time point of the land period, with the data value of step (A02), the maximum, minimum, average or integral value of the acceleration and angular velocity in each axial direction at the time point of the landing period is taken out. .

(A05) Substituting the maximum, minimum, average or integral values of the required acceleration and angular velocity data values in the knee abduction torque, adduction torque and average torque formula respectively to obtain the knee joint abduction torque , the value of the adduction torque and the average torque.

The wearing article 11 in the above step (A01) may be knee pads and sports pants. , trousers, straps or other wearables 11 that can be worn on the preset wearing position 21 of the lower leg 2; and the motion sensor 12 can be an IMU sensor (Inertial measurement unit) A sensor composed of a gyroscope or a magnetometer or the like is used to sense the acceleration and angular velocity generated during the movement. However, the components inside the motion sensor 12 are conventional techniques, so the details are not described in detail. .

Furthermore, the motion sensor 12 in the above step (A01) is preferably implemented by electrically connecting the electronic device directly to the electronic device to transmit the values of the acceleration, angular velocity and the like detected by the motion sensor 12 through the wire. For the electronic device, in the actual application, the motion sensor 12 may further be provided with a wireless transmission module, and the electronic device also has a wireless transmission unit therein, and the motion sensor 12 can be wirelessly The transmission method transmits the values of acceleration and angular velocity detected by the motion sensor 12 to the electronic device; the wireless transmission module and the wireless transmission unit may be a Bluetooth wireless transmission interface, and a global mobile communication system (GSM). a transmission interface such as a packet radio service (GPRS), a code division multiple access system (CDMA), or a wireless network (such as Wi-Fi, Wireless Lan, Zigbee, etc.); and the preferred implementation state of the electronic device may be a desk A computer, but in practice, it can also be a smart phone, tablet, notebook or other electronic device with computing functions.

Moreover, the predetermined wearing position 21 of the lower leg 2 in the above step (A01) is preferably the Tibial tuberosity of the lower leg 2, but in actual application, it may also be around the tibial tuberosity.

However, the method of the pre-scheduled period and the swing period in the above step (A03) was proposed by Gouwanda and Senanayake in 2011. The way, as shown in the third figure, it can be clearly seen from the figure that the vertical axis of the graph is the angular velocity, and the horizontal axis is the time. When the user moves and the calf 2 is displaced, the calf 2 is preset to wear. The angular velocity generated at position 21 will be as shown in the curve. The two highest points in the curve are the time points when the calf 2 swings in the air, and the first low point after the swing is the time point when the heel strikes the ground. The low point before the swing is the time point when the toe is off the ground. However, the time point from the time of the heel to the ground to the point where the toe is off the ground is the time point of the ground period, which can be done by the graph of the angular velocity versus time. Don't miss the time of the season and the swing period.

In addition, the abduction torque formula in the above step (A05): A=-a ₁ . B ₁ -a ₂ . B ₂ +a ₃ . B ₃ -a ₄ . B ₄ +a ₅ . B ₅ +a ₆ . B ₆ -a ₇ . B ₇ +a ₈ . B ₈ +a ₉ . B ₉ -a ₁₀ . B ₁₀ +K; A = abduction torque; a ₁ is between 5.0 and 4.4, a ₂ is between 1.0 and 0.4, a ₃ is between 6.0 and 4.6, and a ₄ is between 17.1. Between ~16.8, a ₅ is between 26.0 and 24.3, a ₆ is between 5.0 and 4.1, a ₇ is between 7.0 and 6.0, and a ₈ is between 40.0 and 38.8. ₉ is between 12.0 and 11.5, a ₁₀ is between 4.0 and 3.2; B ₁ = angular velocity Z-axis mean (mean), B ₂ = angular velocity Z-axis minimum (min), B ₃ = acceleration Z Axis minimum value (min), B ₄ = angular velocity X-axis integral value, B ₅ = acceleration X-axis average value (mean), B ₆ = angular velocity Y-axis integral value, B ₇ = angular velocity Z-axis integral value, B ₈ = acceleration Y-axis integral value, B ₉ = angular velocity X-axis average value (mean), B ₁₀ = angular velocity Y-axis average value (mean), and K is a natural number constant.

And the formula of the adduction torque in the above step (A05): C=-c ₁ . D ₁ -c ₂ . D ₂ +c ₁ . D ₃ -c ₄ . D ₄ -c ₅ . D ₅ +c ₆ . D ₆ -c ₇ . D ₇ -c ₈ . D ₈ +c ₉ . D ₉ +c ₁₀ . D ₁₀ -c ₁₁ . D ₁₁ +c ₁₂ . D ₁₂ -c ₁₃ . D ₁₃ +K; C = adduction torque; c ₁ is between 30.0 and 29.0, c ₂ is between 1.0 and 0.6, c ₃ is between 29.0 and 27.5, and c ₄ is between 3.0 Between ~1.0, c ₅ is between 115.0 and 113.0, c ₆ is between 447.0 and 445.3, c ₇ is between 52.0 and 51.0, and c ₈ is between 17.0 and 15.7. ₉ is between 47.0 and 45.3, c ₁₀ is between 39.0 and 38.7, c ₁₁ is between 502.0 and 501.6, c ₁₂ is between 16.0 and 15.6, and c ₁₃ is between 4.0 and 3.2; D ₁ = angular velocity Z-axis mean (mean), D ₂ = angular velocity X-axis minimum (min), D ₃ = acceleration Z-axis minimum (min), D ₄ = angular velocity Z-axis minimum (min ), D ₅ = acceleration Z-axis integral value, D ₆ = acceleration Y-axis average value (mean), D ₇ = acceleration Z-axis maximum value (max), D ₈ = angular velocity X-axis integral value, D ₉ = acceleration X-axis Mean, D ₁₀ = angular velocity Z-axis integral value, D ₁₁ = acceleration Y-axis integral value, D ₁₂ = angular velocity X-axis average value (mean), D ₁₃ = angular velocity Y-axis average value (mean), K is Natural number constant.

And the average torque formula in the above step (A05): E = -e ₁ . F ₁ +e ₂ . F ₂ -e ₃ . F ₃ +e ₄ . F ₄ -e ₅ . F ₅ -e ₆ . F ₆ +e ₇ . F ₇ +e ₈ . F ₈ +e ₉ . F ₉ -e ₁₀ . F ₁₀ +e ₁₁ . F ₁₁ +e ₁₂ . F ₁₂ -e ₁₃ . F ₁₃ +e ₁₄ . F ₁₄ -e ₁₅ . F ₁₅ +K; E = average moment; e ₁ is between 21.0 and 19.0, e ₂ is between 7.0 and 5.0, e ₃ is between 1.0 and 0.02, and e ₄ is between 18.0 and Between 17.7, e ₅ is between 2.0 and 0.4, e ₆ is between 62.0 and 60.5, e ₇ is between 1.0 and 0.006, and e ₈ is between 218.0 and 216.4, e ₉ It is between 24.0 and 23.0, e ₁₀ is between 11.0 and 10.1, e ₁₁ is between 51.0 and 49.2, e ₁₂ is between 28.0 and 27.9, and e ₁₃ is between 243.0 and 242.2. between, e ₁₄ is between 11.0 ~ 10.6, e ₁₅ is between 3.0 ~ 2.5; F ₁ = Z-axis angular velocity average value (mean), F ₂ = acceleration in the Y-axis minimum value (min), F ₃ = angular velocity X-axis minimum (min), F ₄ = acceleration Z-axis minimum (min), F ₅ = angular velocity Z-axis minimum (min), F ₆ = acceleration Z-axis integral value, F ₇ = angular velocity Y-axis Maximum value (max), F ₈ = acceleration Y-axis average value (mean), F ₉ = acceleration Z-axis maximum value (max), F ₁₀ = angular velocity X-axis integral value, F ₁₁ = acceleration X-axis average value (mean) , F ₁₂ = integrated value of the angular velocity of the Z-axis, F ₁₃ = integral value of acceleration in the Y-axis, F ₁₄ = X-axis angular velocity average (mean), ₁₅ = Y-axis angular velocity average value F (mean), K Natural number constant.

For example, when using the method proposed by Gouwanda and Senanayake in 2011 to obtain the time point on the angular velocity versus time curve, you can refer to the fourth and fifth figures, and land in the map. At the time point, the maximum, minimum or integral values of the acceleration and angular velocity in each axial direction are taken out and substituted into the formula of the adduction torque formula, the abduction moment and the average moment, wherein: the abduction torque formula is substituted for B. ₁ = 6.602, B ₂ = - 6.934, B ₃ = - 6.759, B ₄ = 7.235, B ₅ = 10.132, B ₆ = 67.529, B ₇ = 4.218, B ₈ = 0.311, B ₉ = 11.084, B ₁₀ = 105.328 , K = -286.11.

In the formula of the adduction torque, D ₁ =13.181, D ₂ =-62.760, D ₃ =-2.444, D ₄ =-8.679, D ₅ =3.650, D ₆ =-1.133, D ₇ =13.444, D ₈ = 12.303, D ₉ = 9.478, D ₁₀ = 9.521, D ₁₁ = -0.818, D ₁₂ = 16.681, D ₁₃ = 87.310, K = -82.88.

In the formula of the average moment, F ₁ =7.590, F ₂ =-5.982, F ₃ =-162.954, F ₄ =-5.952, F ₅ =-19.265, F ₆ =2.038, F ₇ =207.201, F ₈ =1.070 , F ₉ =12.120, F ₁₀ =10.189, F ₁₁ =9.394, F ₁₂ =4.919, F ₁₃ =0.703, F ₁₄ =14.992, F ₁₅ =91.422, K=-243.326.

When the user substitutes the above values in the formula of the abduction moment formula, the adduction torque and the average moment, the abduction torque A=-119.306 (Nmm), the adduction torque C=277.205 (Nmm) and the average moment can be calculated. E=299.421 (Nmm), the user can compare and analyze the values of the abduction torque, the adduction torque and the average torque with the preset values of the built-in database to understand the user's abduction torque, Whether the value of the adduction torque and the average torque meets the preset value, so as to understand whether the user's posture is correct when moving; as for the built-in database, the majority of people can use the conventional motion analysis system for a long time. The database of the external display torque, the adduction torque and the average torque is established by the system and the force plate. However, in actual application, the extension torque and the internal torque can be established by the wearer 1 for a long time. Average torque database.

In addition, if the user wears the wearable device 1 for a long period of time, a plurality of sets of values of the abduction torque, the adduction torque, and the average torque are obtained, so that the user can detect the presence or absence of a bad posture during the long-term movement, thereby preventing the long-term posture from being bad. And the damage caused to the knee joint.

The present invention has the following advantages:

(1) The wearing device 1 is worn at the preset wearing position 21 of the lower leg 2, that is, without using another space place, it is not restricted by the use on the field compared to the conventional instrument for use. It is convenient to carry and use, and because it is not restricted by the field, the user can be measured at any time and any place, thereby monitoring and monitoring whether the user moves with or without a bad posture, thereby preventing the posture. Poor and harmful to the knee joint.

(2) Furthermore, the wearable device 1 has a simple overall structure and few internal electronic components, so that it has the advantage of low manufacturing cost compared with the conventional instrument, thereby improving product competitiveness.

Therefore, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The method for calculating the knee joint torque of the present invention first wears the wearing article 11 of the wearing device 1 on the user's lower leg 2 The preset wearing position 21, and the motion sensor 12 mounted on the wearing object 11 is aligned with the preset wearing position 21, and the motion sensor 12 is connected to the electronic device when the user starts Moving, the motion sensor 12 can be used to detect the acceleration and angular velocity of the calf 2 displacement, and the acceleration and angular velocity are calculated by the electronic device. The data values and displacement data in the three axial directions are respectively used to determine the displacement data by using the discrimination method of the ground period and the swing period, so as to obtain the time point of the land period, the time point at the landing time can be taken out. The data value of the acceleration and angular velocity, and then the data value is substituted into the knee abduction, adduction and average torque formula to obtain the knee joint outreach, adduction and average torque, because the wearing device 1 is worn on the lower leg 2, you can get the abduction, adduction and average torque, so you can not be restricted by the field, and you can monitor the user at any time, so as to prevent the knee joint caused by poor posture, so the above can be achieved The implementations, the operation steps and the like of the effects are all covered by the present invention, and such simple modifications and variations of the equivalent implementation contents are all included in the scope of the patent of the present invention and are combined with Chen Ming.

In summary, the method for calculating the knee joint torque of the present invention can achieve its efficacy and purpose in practical application and implementation. Therefore, the present invention is an excellent research and development, and is an application for conforming to the invention patent. Applying according to law, I hope that the trial committee will grant this case as soon as possible to protect the inventor's hard work in research and development, and if there is any doubt in the audit committee, please do not hesitate to give instructions, the inventor will try his best to cooperate, and feel really good.

Claims (5)

A method for calculating a knee joint moment, the steps of which are: (A01) first wearing the wearing device of the wearing device on the tibial trochanter of the user's calf, and aligning the motion sensor mounted on the wearing object with the calf The humerus is thickened, and the motion sensor is connected to the electronic device with arithmetic function; (A02) the user starts to move, and the motion sensor is used to detect the acceleration and angular velocity of the calf displacement, and by the electronic device Calculate the data values of the acceleration and angular velocity in the three axial directions respectively, and obtain the displacement data including the acceleration versus time graph or the angular velocity versus time graph; (A03) reuse the ground period and the swing period to distinguish the displacement The data is judged to obtain the time point of the land period; (A04) after obtaining the time point of the land period, and in conjunction with the data value of the step (A02), the acceleration in each axial direction at the time point of the landing period is taken out and The maximum, minimum, mean or integral value of the angular velocity; (A05) and the maximum value of the acceleration and angular velocity data required for substituting the knee abduction torque, the adduction torque and the average torque formula respectively Minimum value, average value or integrated value, to obtain a development beyond the knee moment, and the average torque value adduction moment, the outer abduction moment formula: A = -a _1. B ₁ -a ₂ . B ₂ +a ₃ . B ₃ -a ₄ . B ₄ +a ₅ . B ₅ +a ₆ . B ₆ -a ₇ . B ₇ +a ₈ . B ₈ +a ₉ . B ₉ -a ₁₀ . B ₁₀ +K, the a ₁ is between 5.0 and 4.4, the a ₂ is between 1.0 and 0.4, the a ₃ is between 6.0 and 4.6, and the a ₄ is between 17.0 and 16.8. a ₅ is between 26.0 and 24.3, a ₆ is between 5.0 and 4.1, a ₇ is between 7.0 and 6.0, a ₈ is between 40.0 and 38.8, and a ₉ is between 12.0. Between ~11.5, a ₁₀ is between 4.0 and 3.2, then B ₁ = angular velocity Z-axis average, B ₂ = angular velocity Z-axis minimum, B ₃ = acceleration Z-axis minimum, B ₄ = angular velocity X-axis Integral value, B ₅ = acceleration X-axis average value, B ₆ = angular velocity Y-axis integral value, B ₇ = angular velocity Z-axis integral value, B ₈ = acceleration Y-axis integral value, B ₉ = angular velocity X-axis average value, B ₁₀ = angular velocity Y-axis average, K is a natural number constant; and the adduction torque formula: C=-c ₁ . D ₁ -c ₂ . D ₂ +c ₁ . D ₃ -c ₄ . D ₄ -c ₅ . D ₅ +c ₆ . D ₆ -c ₇ . D ₇ -c ₈ . D ₈ +c ₉ . D ₉ +c ₁₀ . D ₁₀ -c ₁₁ . D ₁₁ +c ₁₂ . D ₁₂ -c ₁₃ . D ₁₃ +K, and c ₁ is between 30.0 and 29.0, c ₂ is between 1.0 and 0.6, c ₃ is between 29.0 and 27.5, and c ₄ is between 3.0 and 1.0. c ₅ is between 115.0 and 113.0, c ₆ is between 447.0 and 445.3, c ₇ is between 52.0 and 51.0, c ₈ is between 17.0 and 15.7, and c ₉ is between 47.0. Between ~45.3, c ₁₀ is between 39.0 and 38.7, c ₁₁ is between 502.0 and 501.6, c ₁₂ is between 16.0 and 15.6, and c ₁₃ is between 4.0 and 3.2. D ₁ = angular velocity Z-axis average, D ₂ = angular velocity X-axis minimum, D ₃ = acceleration Z-axis minimum, D ₄ = angular velocity Z-axis minimum, D ₅ = acceleration Z-axis integral, D ₆ = acceleration Y Axis average, D ₇ = acceleration Z axis maximum, D ₈ = angular velocity X axis integral value, D ₉ = acceleration X axis average value, D ₁₀ = angular velocity Z axis integral value, D ₁₁ = acceleration Y axis integral value, D ₁₂ = angular velocity X-axis average, D ₁₃ = angular velocity Y-axis average, K is a natural number constant; as for the average moment formula: E = -e ₁ . F ₁ +e ₂ . F ₂ -e ₃ . F ₃ +e ₄ . F ₄ -e ₅ . F ₅ -e ₆ . F ₆ +e ₇ . F ₇ +e ₈ . F ₈ +e ₉ . F ₉ -e ₁₀ . F ₁₀ +e ₁₁ . F ₁₁ +e ₁₂ . F ₁₂ -e ₁₃ . F ₁₃ +e ₁₄ . F ₁₄ -e ₁₅ . F ₁₅ +K, and e ₁ is between 21.0 and 19.0, e ₂ is between 7.0 and 5.0, e ₃ is between 1.0 and 0.02, and e ₄ is between 18.0 and 17.7. e ₅ is between 2.0 and 0.4, e ₆ is between 62.0 and 60.5, e ₇ is between 1.0 and 0.006, e ₈ is between 218.0 and 216.4, and e ₉ is between 24.0. Between ~23.0, e ₁₀ is between 11.0 and 10.1, e ₁₁ is between 51.0 and 49.2, e ₁₂ is between 28.0 and 27.9, and e ₁₃ is between 243.0 and 242.2. ₁₄ is between 11.0 and 10.6, e ₁₅ is between 3.0 and 2.5, then F ₁ = angular velocity Z-axis average, F ₂ = acceleration Y-axis minimum, F ₃ = angular velocity X-axis minimum, F ₄ = acceleration Z-axis minimum, F ₅ = angular velocity Z-axis minimum, F ₆ = acceleration Z-axis integral, F ₇ = angular velocity Y-axis maximum, F ₈ = acceleration Y-axis average, F ₉ = acceleration Z-axis Maximum value, F ₁₀ = angular velocity X-axis integral value, F ₁₁ = acceleration X-axis average value, F ₁₂ = angular velocity Z-axis integral value, F ₁₃ = acceleration Y-axis integral value, F ₁₄ = angular velocity X-axis average value, F ₁₅ = angular velocity Y-axis average, K is a natural number constant. The knee joint torque calculation method according to claim 1, wherein the wearable item in the step (A01) is a knee protector, a sports trousers, a trousers or a strap. The knee joint torque calculation method according to claim 1, wherein the motion sensor in the step (A01) is an IMU sensor. The method for calculating a knee joint torque according to claim 1, wherein the electronic device in the step (A01) is a desktop computer, a smart phone, a tablet computer or a notebook computer. For example, the method for calculating the knee joint moment according to the first application of the patent scope, wherein the method of the landing period and the swing period in the step (A03) is the way of Gouwanda and Senanayake.