ABSTRACT
Loading force acting between human and the ground, called ground reaction force (GRF), can provide essential sources of information to analyze human dynamics. Force plates are believed to be the “golden standard” to measure the three orthogonal components of GRF. The use of this method, however, brings some limitations. One example is that the task may be restricted depending on the number and size of force plates which may constrain the natural movement of the subjects (Forner-Cordero et al., 2006; Oggero et al., 1999). Alternative approaches have, therefore, been considered to estimate GRF without force plates. The recent attempts include the use of positional data for vertical GRF (Bobbert et al., 1991), and pressure insoles and artificial neural networks for horizontal GRF (Savelberg & de Lange, 1999). Human body during the impact can be considered as a mechanical system with masses, springs and dampers (Liu & Nigg, 2000) and spring-damper-mass models have, therefore, been widely used to simulate human locomotion.
