Biomechanics Simulation Analysis For Typical Movements Of Human

The human body is an extremely complex system, individual differences, diversity and the limitations of in vivo experiments, making the research work about biomechanical characteristics of the human body difficult. At the same time, with the development of economy, the rising standards of people's living and the continuous improvement of medical conditions, their demand to improve quality of life themselves becomes more intense. How to prevent sports injury, improve diagnostic and treatment capacity of the neuromusculoskeletal and orthepedic disease and improve the effects of prostheses, become an important task for biomedical researchers in related fields. Biomechanical study of a human body is to study the theory of human biology and the movement mechanism from a mechanical point of view, so as to provide strong theoretical guidance and help for the development of clinics and rehabilitation.This dissertation is based on the key project‘Mechanical virtual human of China'supported by National Natural Science Foundation of China (NSFC, No.30530230) and the key international cooperation research project ‘Research on the properties of hip and knee joints and basic design of artificial joints for Asia race'supported by NSFC (No.30810103908). The three-dimensional (3D) geometrical model and biomechanical model of standard human musculoskeletal system have been established. Then, the transform method from standard human musculoskeletal system to individual human musculoskeletal system has been constructed. The software which includes dynamical calculation and muscle force estimation has been developed. The kinematic and dynamic analyses have been carried out for human typical movement. Also, activations of the related muscles have been calculated during movement. The main contents are listed as following:1) The 3D geometrical model of standard human skeleton has been established based on cryosectional image data using medical image processing technology and reverse engineering method. Then, the local coordinates of origin and insertion points of muscles on upper limb and lower limb have been determined. Also, the action force lines of the muscles have been constructed. Finally, the human standard musculoskeletal system has been constructed.2) The measurements of basic parameters of individual human, which include motion capture measurement, ground reaction force, EMG measurement and so on, have been constituted. Joint coordinate system (JCS)-based method on coordinate transformation of attachment points between muscle and bone, and the scaling and match method of the musculoskeletal system have been established. Then the standard human musculoskeletal system can be applied to analyze individual easily.3) Numerical calculation methods for kinematics and kinetic have been described in detail. A multi-functional software (including two methods: inverse dynamics-based static optimization algorithm and the EMG-based algorithm) for human muscle force estimation have been developed. The performance of this software is good. It is with strong visualization capabilities, can observe real-time three-dimensional motion and show the curve of muscle force which selected. Currently, the software is being software copyright registration.4) The motions of 40 volunteers with six typical movements (walking, running, squatting, kneeling, stair climbing), no load or weight-bearing state, have been captured. The ground reaction force and EMG of major muscles in lower limb have been measured synchronously.5) By using of the results obtained above, joint angles of hip, knee and ankle, joint forces and joint torques, and activations of main muscles during the six typical movements have been calculated and analyzed. These can help us to understand the human movement of such activities and provide scientific data for prosthesis design.In short, this dissertation has stated the human musculoskeletal biomechanical model, and the related experimental and calculated methods established by us. Lower extremity kinematics, kinetics and muscle activations during typical human movement have been calculated and analyzed. The model and methods can be applied to the research of human biomechanics widely. This work can provide a theoretical basis and useful information for the design of Asian artificial joint.