Robotic arm for maintaining a tool in a desired orientation

A PERFECTED ROBOTIC ARM SYSTEM (1) FOR HANDLING THE LAMINATUBE (11) LOCATED INSIDE THE WEIGHT CHANNEL HEAD THROUGH THE NUCLEUS (13) OF A NUCLEAR STEAM GENERATOR. THE SYSTEM (1) INCLUDES A ROBOTIC ARM (3) WHOSE SHOULDER AND ELBOW JOINTS (42, 44, 45, 47, 48, 49) ARE ROTABLE ONLY ON THE PLANE PARALLEL TO THE LAMINATUBE (11), TO ELIMINATE THE IMPOSITION OF TORQUE TORQUE INDUCED INTO ELECTRIC MOTORS ACTUATING THESE JOINTS, AS WELL AS TO MINIMIZE THE POSSIBILITY OF MECHANICAL INTERFERENCE BETWEEN THE ARM (3) AND THE WALLS 15 OF THE PASS-THROUGH HEAD. EACH OF THE MOTORIZED JOINT ASSEMBLIES (42, 44, 45, 47, 48, 49) OF THE ARM (3) INCLUDES REDUCERS (100, 102) THAT MOVE THE JOINT AND DRIVE THE DRIVE TRAIN (81). THE ROBOTIC ARM SYSTEM CIRCUIT CONTROL ASSEMBLY (7) INCLUDES A PROCESSING CONTROL UNIT (CPU) (273) ABLE TO SIMULTANEOUSLY DRIVE JOINT ASSEMBLIES (42, 44, 45, 47, 48, 49) AND ANY COMPUTER OPERATED MECHANISMS ASSOCIATED WITH EXTREME EFFECTORS (5, 27) DISTRIBUTED THROUGH THE ARM.