Exoskeleton Dynamic Modeling and Identification with Load and Temperature-Dependent Friction Model

Frictional losses within the transmission components of robotic manipulators are often modeled as a constant Coulomb friction force or/and a viscous friction force proportional to the sliding velocity. However, the variation in contact forces of lubricated surfaces of the mechanical transmission system influences the friction force. The joint temperature also has an effect on the variation of the latter. Hence, the importance of considering the parameters mentioned in the dynamic model of the robotic manipulator. This paper presents a new load and temperature-dependent model that will be subsequently identified from experimental measurements carried out on two-link robotic manipulator with different loads.