Interface Design for Physical Human-Robot Interaction using sensorless control

Abstract

The rapid increase in the usage of robots has made interaction between a human and a robot a crucial field of research. Physical human–robot interaction constitutes a relevant and growing research area. Nowadays robots are used in almost all areas of life, such as in households, for education and in medicine. Therefore, many research studies are being conducted on ergonomic human–robot interfaces enabling people to communicate, collaborate and to teach a robot through physical interaction.This thesis is focused on developing a physical human-robot interface by means of which the user is able to control a walking humanoid by exerting force. Through physical contact with the robot arm, a human can influence the direction and velocity of the robot walk. In other words, the user leads the humanoid by the hand, and the robot compensates this external force by following the user.The developed interface offers a method of sensorless force control. Instead of the traditional approach using force/torque measurement, the fact that a DC motor’s torque is proportional to the armature current was applied. Two different control algorithms were implemented and compared. Consequently, a usability test was conducted for different interfaces to find the one which was the most ergonomic.