Abstract: For human assistance device, the particular properties are usually focused on high precision, compliant interaction, large torque generation and compactness of the mechanical system. To realize the high performance of lower extremity augmentation device, in this paper, we introduce a novel control methodology for compact elastic module. Based on the previous work, the elastic module consists of two parts, i.e., the proximal interaction module and the distal control module. To improve the compactness of the exoskeleton, we only employ the distal control module to achieve both purposes of precision force control and human intention recognition with physical human-machine interaction. In addition, a novel control methodology, so-called high precision data-driven force control with disturbance observer is adopted in this paper. To assess our proposed control methodology, we compare our novel force control with several other control methodologies on the lower extremity augmentation single leg exoskeleton system. The experiment shows a satisfying result and promising application feasibility of the proposed control methodology.

Key words: series elastic actuator, Human-Machine Interaction (HMI), force control, model prediction control, exoskeleton, bioinspired