Development of Foot Modules of an Exoskeleton Equipped with Multiple Sensors for Detecting Walking Phase and Intent

Abstract

This paper presents design and application of foot modules in exoskeleton. Detecting the walking phase and intent is most important data for controlling the wearable exoskeleton. The zero moment point (ZMP) trajectory in the robot foot support area is significant criterion for a stability of the walk. The ZMP is calculated by measured force / torque data and Force / Torque sensor (F/T sensor) can measure that. But, the thick foot module is inconvenient to walking. For such a reason, most foot modules are developed using the film type sensors such as force sensing resistor (FSR), ground contact sensor such as tape switch and so on. In this paper, the foot modules equipped optimal design of 3-axis F/T sensor and ground contact sensor are presented and experimental application of detecting the walking phase using both sensors is introduced.