Drawing Pressure Estimation Using Torque Feedback Control Model of A 4-DOF Robotic Arm.

This paper we introduce a torque feedback control (TFC) model to estimate pressure of the hand on a 4-DOF robotic arm of Betty, a humanoid robot. Based on several preliminary experiments of different stroke patterns, we measured and analysed the torque replies of Betty's servos in order to model the torque feedback. We developed a robust humanoid system to create sketch like drawing with limited hardware which has no force sensor but basic torque feedback from servos to estimate pressure apply on drawing pad. We investigated the efficiency of using the TFC in the drawing task based on several different stroke patterns. The experimental results indicate that the TFC model successfully corrected the errors during the drawing task.