A novel 3-DOF optical force sensor for wearable robotic arm

This paper presents a novel 3-DOF optical force sensor for the wearable robotic arm. Precise sensing of human motion is still a challenge. As human motion detection sensors are expected to generate the real time data, with simultaneous measurement of multiple degrees of freedom. The optical sensing is considered to be standard for monitoring the human motion. The optical sensor is consists of high speed camera with integrated DSP (Digital Signal Processor). The DSP use to detect the changes in the sequence of frames to calculate the direction and displacement of its motion in a plane. On the other hand optical sensor eliminates the requirement of being in contact with the subject. Hand is the end-effecter of the arm and can be controlled by a 3-DOF (degree of freedom) shoulder, 2-DOF elbow and 2-DOF wrist joint. In this paper we present a new technique to measure the human’s hand movement in 3 dimensions translation frame. An intelligent computational method for this sensory system to measure the applied force is also developed. The optical force sensor was calibrated and then several experiments were conducted to check the feasibility of sensory system with the wearable robotic arm.