Adaptive threshold for robot manipulator collision detection using fuzzy system

Abstract

The topic of collision detection was recently addressed in the literature due to the demand of safe human–robot collaboration. Several methods have been proposed for this task; some of these methods use external sensors while others do not (sensor-less). The classical sensor-less method is attained by setting a threshold to detect the change in torque/current. This method is simple and applicable for real-time implementation and does not require any prior information on the robot dynamical model. However, any wrong choices on the threshold value might lead up to undesirable performance. Therefore, in this paper we propose an evolved solution using the classical method while operating the fuzzy logic system. The enhanced system results in an adaptive collision threshold based on the variation of the robots speed and acceleration. The system is presented in this paper along with the experimental setup and the implementation steps.