편마비 다리환자를 위한 보행보조로봇의 발목 2축 힘센서 설계

Abstract

This paper describes the design and manufacture of a ankle two-axis force sensor of a walking assist robot for hemiplegic leg patient. The walking assist robot for the hemiplegic leg patient can safely control the robot by detecting whether the foot wearing the walkingassist robot is in contact with the obstacle or not. To do so, a two-axis force sensor should be attached to the robot's ankle. The sensoris used to measure the force of a patient's ankle lower part. The two-axis force sensor is composed of a Fx force sensor, a Fy force sensor and a pulley, and they detect the x and y direction forces, respectively. The two-axis force sensor was designed using by FEM(FiniteElement Method), and manufactured using by strain-gages. The characteristics experiment of the two-axis force sensor was carried outrespectively. The test results indicated that the interference error of the two-axis force sensor was less than 1.2%, the repeatability errorand the non-linearity of the two-axis force sensor was less than 0.04% respectively. Therefore, the fabricated two-axis force sensor can be used to measure the force of ankle lower part in the walking assist robot.