With the development of computing technology in recent years, numerical simulation system is developed to calculate the body behavior on a computer. There are some advantages of applying numerical simulation in vehicle development. For example, the cost reduction and safety. But the validity of numerical model needs to be shown. The experiment of human behavior was performed under stationary vibration but it does not cover the body behavior such as the movement caused by the influence of lateral acceleration that can be seen in the driving car. Furthermore, motion of body may be affected Mental Workload (MWL). In this research, we have tested experiment on the relationship between MWL and motion of body.
