Modeling And Analysis Of Muscle Force In The Upper A Flexing Process

Nowadays,the faster life and working pace results in people's declining physical fitness,thus more and more people choose to go to the gym for a change.However,most of people can not measure their muscle strength to intuitively understand the changes during exercise,so that it's difficult to have a scientific excises.The muscle strength changes of the main flexors(biceps,diaphragm and diaphragm)are quantitatively analyzed by establishing a muscle force model of the upper limb flexion process,providing a theoretical basis for upper limb muscle training,to make training more targeted and efficient.According to the physiological structure and movement characteristics of the upper limbs of the human body,a reasonable human upper limb rigid model is established,and the muscle is replaced by a straight line to establish a linear model of the muscle.The spatial position coordinates of each muscle start and end point are obtained by establishing the upper limb coordinate system.By refining the rigid body model of the forearm,the forearm rotation angle variable is added to the muscle force arm model to make the muscle force arm value contains two variables(elbow joint bending angle and forearm rotation angle)in order to match the established upper limb muscle force model to more training scenarios.In the human upper limb movement experiment,the motion data of the upper limb is collected by the wireless independent sensing system,which mainly includes the movement angle,angular velocity and angular acceleration of the elbow joint.The joint moment of the elbow joint was obtained by inverse dynamic analysis of the elbow joint using the Lagrangian dynamic equation.According to the principle that the nerve control muscle consumes the minimum energy,the muscle strength of the biceps,diaphragm and diaphragm is solved by the constraint optimization method through the elbow joint moment balance equation and the condition of the muscle force.While collecting the motion signal,the sEMG signal of the biceps muscle is collected.Then the muscle activation degree is obtained with the preprocessing of sEMG signal,and the muscle force of the biceps muscle is calculated by the muscle activation degree.And the biceps muscle strength calculated by the two methods is compared to verify the validity of the model.Finally,this thesis analyzes the changes of muscle force of the biceps brachii,brachialis and brachioradialis under different exercise states through multiple experiments,and provides a theoretical basis for future upper limb strength training.