Modelling and dynamics of miliwalking robots

The results of simulation and measurement of the contact forces of miliwalking HERMES/sup TM/ robot is presented. HERMES is a six-legged miliwalking robot which incorporates high-powered processing, rich sensing and high mobility into a compact body. To develop the kinematics and dynamics of HERMES machine the model of real insect locomotion was used. In the dynamical model two contact-impact models are considered. In the first approach the model was built using general multibody formalism with differential algebraic equation the sign of the constraint force was a test to decide if the respective contact will break or not. This approach implicitly assumes that the contact forces are continuous with respect to time. The general results of the paper concern mainly with this approach. The second approach proposed by Nikravesh (1990) is based on the model which uses the general trend of the Hertz contact law. The dissipated energy in impact is represented by hysteresis form of damping function.