A new template model for optimization studies of human walking on different terrains

Human movement, as for example human gait, can be considered as an optimal realization of some given task. If the optimization criteria for different types of gait were known, this knowledge could help to improve robot motion generation and control, also for complex walking motions on slopes or stairs. Unfortunately, in general the criteria for which the naturally performed human motion is optimal, are not known. Therefore, in this article we study the relevance of different measurable quantities in human locomotion based on human motion capture data and a new template model that is able to capture the main dynamical characteristics we are interested in. To this end we introduce a three dimensional actuated walking model, with an upper body, two actuated legs and two point-masses as feet. Taking into account single and double support phases and the impact at touch down, the model is suitable to reproduce realistic three dimensional center of mass and swing foot trajectories even in constrained environments. In this article, we focus on walking up and down stairs and compare the observed quantities.