Ambulatory estimation of ankle and foot dynamics and center of mass movement

Traditionally, human body movement analysis is done in socalled ‘gait laboratories’, equipped with several measurement systems such as optical position measurement systems, EMG or force plates. The measured signals are used to estimate important gait variables. An important variable is the center of mass, an imaginary point at which the total body mass can be assumed to be concentrated. Several methods exist for center of mass estimation, of which the segmental kinematics method and the double integration of ground reaction force method are the most important ones. Other important variables are joint moment and powers. These can be estimated from estimations of body movement and ground reaction forces by applying inverse dynamics methods. A major drawback of the existing systems is the restriction to the laboratory environment. Therefore research is required for the development of measurement systems to perform these measurements in an ambulatory environment. The objective of this study is to give an overview of the possibilities of the forceshoe. The forceshoe is an ambulatory measurement system able to measure the ground reaction force and movement of foot and ankle.