DYNAMICAL PRINCIPLE OF LIFTING ACTION

Abstract

The manual lifting is a prevalent action during daily life and professional work. So lowback pain is common among, these human. Many experts make researches on this subject in various fields with experimental method. In this paper our research and analysis based on classical dynamic method. We simulated the lifting movement in the dynamic multi-segment model and defined O (the angle between leg and ground) as generalized coordinate. Hence the equations of multi-body system were established. Through solving these equations, the angular velocity and angular accelerate of hip angle B', B'' and internal forces and moment of hip Nx, Ny, M were obtained. Especially, analytical solution of O', was be obtained, it is convenient to further research intemal mechanics of lifting 0 Based on above analysis, the conclusions show that main influence of Nx, Ny,M is the change of angular acceleration O''. The key factor to avoid injure is control the type of smooth lifting.