Non-linear Modelling of Human Body Dynamic

Adam Zawadzki , Tomasz Mirosław

Abstract

In the paper authors present a concept and a modeling method of the static and dynamic loads of human body’s parts: bones and muscles during movement. Currently the problem of human body modelling is very important for many domains of our “better life” programs e.g.: an automotive – to find the best solution for human protection during accidents, sport – to find the most efficient and least tiring movements, to the health protection or extend the active life of the elderly. The human body is not a rigid multi-body system, but elastic, flexible and varying according to time. It consists of semi-stiff bones, elastic muscles and tendons. Other parts like stomach or liver are hanging on elastic wires and move relatively to each other during the whole acceleration process etc. All those elements can be broken or fatigued under some load. So the model of human body is not linear and shouldn’t be modelled by linear equation sets. Authors present the concept of human body modelling based on three types element chain. One type are “bones” that are joined in joints and conduct loads to the support surface; the elastic tendons that keep the joints and propel bones rotation in joints, and muscles that generate forces for stabilization system or for propelling the bones. In paper the simplified model of human body built in MATLAB/Simulink software is presented. Some results of simulation e.g. load of a knee during squat or landing after jump are compared with real test results