Design of a joint angle measurement system for the rotary joint of a robotic arm using an Incremental Rotary Encoder

Abstract

The design of a prototype system that measures the joint angles of the rotary joint of a robotic exoskeleton is presented in this work. An incremental rotary encoder is a sensor that can be connected to any rotary joint to measure the angle of rotation, speed of rotation, direction of rotation (clockwise or counter-clockwise motion) as well as the acceleration of a joint. The measurement system using a rotary encoder which generates an electrical signal either analog or digital according to the rotation movement was designed in this work. A prototype rotary joint having a 270° range of motion was fabricated with ABS plastic using 3D printing and then connected to an incremental rotary encoder to measure its speed and angle of motion. A robotic exoskeleton was then proposed to be used with the tested and developed measurement system.