Modelling Characteristics of Human-Robot Interaction in an Exoskeleton System with Elastic Elements

In the paper, problem of modelling the human robot interactions in an exoskeleton system is investigated. In particular, a the case of a lower limb exoskeleton is considered. The interaction is supported by a special connector device featuring elastic elements and pressure sensors, allowing measuring the relative position of the human body and the mechanism links. An algorithm for calculating the position of the human body using the feedback from the pressure sensor is presented. Simulation results taking into account the noise and quantization of the sensor output showed validity of the proposed algorithm. Further simulations allowed to analyze the behavior of the control system in the case of harmonic inputs over a range of different frequencies.