2019 Volume 55 Issue 9 Pages 520-528
This paper presents a contact force distribution feedback control system for developing safe wearable assistive robots. In order to ensure the safety of the user wearing an assist robot being different structure from the assisting part (e.g. entire torso assist with several actuators), a control system based on contact force distribution measured via tactile pressure sensors (pressure distribution sensors) is proposed. By utilizing the tactile sensors on the robot's surface, the robot can measure physical contact force distribution as pressure distribution and control it to suppress excessive. In our previous research, a control methodology with pseudo torque generated from maximum contact force measured by tactile sensors was proposed, however, amplitude of contact force needed to reduce according to pain tolerance of human body parts. A control methodology based on inverse kinematics, a known methodology on the field of serial link-type manipulators, is presented, and confirmed to be effective to improve safety from conventional torque-base control methodology on computer simulations.
