an isolated force / torque sensor assembly for a force controlled robot includes an end effector for operatively attaching to an arm of the force controlled robot , the end effector having a gripping portion adapted to be gripped by a hand of a user , and a force / torque sensor adapted to be disposed between the gripping portion and the arm of the robot , the force / torque sensor having a high force end effector interface adapted to be attached to the arm of the robot , a low force end effector interface operatively attached to the gripping portion , and a transducer disposed between the high force end effector interface and the low force end effector interface for reacting to loads applied to the low force end effector interface for user controlled positioning of a surgical tool and for generating corresponding output signals , and wherein the transducer is bypassed for high loads .