Research On Lower Limb Muscle Force During Human Walking

As an emerging discipline of scientific and technological progress,medical engineering intersection is favored by many disciplines such as medicine,sports,bionics and so on.In addition,in the working environment of many mechanical fields,in order to ensure human safety and improve human work efficiency,it is necessary to deeply study the interaction between human and machine.The combination of advanced medical devices and scientific information processing technology provides new ideas for human research and improving many functions of human body.Muscle is the source of biological power.The dynamic characteristics of muscle force during exercise is one of the main contents of biomechanics and bionics.However,the implementation of anatomical experiments is not easy,so it is difficult to measure muscle force directly.Therefore,this paper analyzes the mechanical properties of muscle from a theoretical point of view,which is of great significance to the development of science.Firstly,combined with the symmetrical characteristics of bilateral withdrawal cycles in the walking process,the human body is simplified into a three joint model of four limb segments including foot bone,tibia,femur and crotch bone,and three joints of hip,knee and ankle,and the positions of the starting and ending points of each muscle of lower limbs in the corresponding limb segments are marked on the model.Then,the muscle tension line is simplified into a straight-line model,and the straight-line distance between the starting point and the ending point of the muscle in space is the length of the muscle.In the process of walking,the base coordinate system is established at the toe and the local coordinate system is established at each limb segment respectively.The spatial distance of muscle starting and ending points is obtained by using the D-H parameter method in the rotation matrix.When calculating muscle force,muscle force can be divided into active muscle force and passive muscle force.Among them,active muscle force is related to muscle length,muscle contraction speed and muscle activation,while passive muscle force is only related to muscle length.The muscle force of lower limb muscles during walking is calculated by using the theoretical formulas of muscle length tension relationship and muscle speed tension relationship.Finally,the bone length of the tester is measured,and the angle sensor is placed at the joint to obtain the experimental data such as joint angle,so as to verify the calculation method of muscle length and muscle force.This research work avoids the experimental means of taking living body as the research object,but solves medical problems from the perspective of engineering.After obtaining the human gait data,based on the theoretical formula,the muscle length and muscle force of the main muscles of the lower limbs during walking are calculated,and verifies the correctness of the calculation results with the reference of the open source software opensim,so as to provide theoretical support for rehabilitation medicine such as intelligent prosthesis and walking robot.