The experiment research of force control based on intelligent prediction in unknown environment

An intelligent prediction algorithm arising from conventional force control models is developed to deal with a force-controlled execution of compliant robot tasks in an unknown environment. The algorithm makes use of the three prediction factors to predict and readjust the desired trajectory given in hybrid position/force control model or reference trajectory given in impedance model when sampling in future. The last prediction shall be re-evaluated first once a prediction starts and, at the same time, the environmental change in curvature and stiffness should be taken into account. The performance of the proposed scheme is illustrated for an open architecture robot platform. The force tracking experiments for the irregular surface in different control model, different tracking velocity, different desired force, different contact stiffness are executed. The experimental results verify that the proposed method of the intelligent prediction has high adaptability to unknown environment in changing. The contact force error in steady state is within 3 percent in the constrained motion.