Abstract: An electromechanical manipulator including gripper elements provided with a plurality of fingers and a sensing element provided for each of the fingers to sense their relative position. The sensing means includes at least one Hall effect element disposed in the body of the gripper element. A magnet element is oriented in a bipolar slide-by mode with respect to the Hall effect element and is disposed for movement with one of the fingers of a gripper element.

Abstract: An overload protection device adapted to be secured between a robot arm and a tool, comprises a floating piston (20) within a cylinder (18). Hall effect sensors (124) are spaced around the cylinder wall and mating magnets (40) are spaced around the piston wall. The cylinder is pressurized to axially align the piston with the cylinder and to position each magnet in alignment with a sensor. When an overload occurs involving either the robot arm or the tool, the magnets are moved relative to the sensors causing the sensors to signal for depressurization of the cylinder. An electronic system (FIG. 27) responsive to the Hall effect sensor signals lights an "overload" LED D1 and triggers a timer circuit T1 which generates a timing pulse of fixed duration. During the duration of the timing pulse, the robot is de-energized. A red LED R is illuminated indicating the robot system is not ready to be operated. Also, a solenoid valve L1 is energized, cutting off the pressure to the cylinder.