Model reference fuzzy learning force control for robotized sewing

A fuzzy model reference adaptive controller for regulating the fabric´s tensional forces applied by a robot during the sewing task is developed. The adaptive fuzzy logic controller closes the loop outside the internal scara robot controller. The robot guides a piece of fabric in a conventional industrial sewing machine while its controller maintains a desired constant tensional force applied to the fabric during the sewing process. In each loop, the proposed controller calculates the appropriate robot end-effector displacement. A force sensor mounted on the wrist of the robot manipulator measures the actual force applied to the fabric, and the formulated force error is used in order to adapt the controllers´ parameters. The performance of the controller is investigated experimentally and the results show the effectiveness of the FMRL approach and its wide range of applications.