Velocity observer based fuzzy PD+I based hybrid force/position control of an industrial robot

A velocity observer based hybrid fuzzy PD+I (VOB-FPD+I) based force plus position controller has been proposed which works well with unspecified robot dynamics for a robot manipulator under constraint environment for unknown joint velocities. The VOB-FPD+I controller has been utilized as a principal controller to be tuned up by orthodox PID gains throughout the complete trajectory tracking process. The validity of the proposed controller has been studied using a 6-Degree of Freedom (DOF) PUMA robot manipulator. The projected hybrid VOB-FPD+I force/position controller followed the desired path closer and smoother.