SIX-AXIS TACTILE SENSING FOR ROBOTS IN NUCLEAR ENVIRONMENTS

ROBOTIC APPLICATIONS IN NUCLEAR REACTORS CAN ENHANCE WORKER SAFETY BY MINIMIZING THEIR EXPOSURE TO RADIATION. TELEOPERATED SYSTEMS, SEMIAUTONOMOUS ROBOTS, AND PROGRAMMABLE ROBOTS CAN BE USED TO PERFORM ROUTINE INSPECTION AND MAINTENANCE TASKS, AS WELL AS REACTOR DECOMMISSIONING AND INCIDENT MANAGEMENT TASKS. BECAUSE OF THE RELATIVELY UNSTRUCTURED NUCLEAR REACTOR ENVIRONMENT, SOPHISTICATED SENSORY FEEDBACK IS REQUIRED FOR EFFICIENT ROBOT OPERATION. ALTHOUGH MANY ROBOTICS RESEARCHERS HAVE CONCENTRATED THEIR EFFORTS ON DEVELOPING VISION SYSTEMS FOR ROBOTS, THE MORE BASIC BUT EXTREMELY IMPORTANT MODALITY OF TACTILE SENSING RECEIVED LESS ATTENTION. TACTILE SENSING CAN PROVIDE CRUCIAL INFORMATION WHEN VISION MAY BE OBSCURED BY A STEAMY OR SMOKY ATMOSPHERE, WHEN REGIONS ARE INACCESSIBLE TO THE CAMERA, WHEN ILLUMINATION IS INADEQUATE,OR WHEN ROBOT OR END-OF-ARM TOOLING BLOCKS THE LINE OF SIGHT. VISION IS OFTEN OF LITTLE USE AT THE CRITICAL MOMENTWHEN OBJECT CONTACT OCCURS. THIS PROJECT SHOULD RESULT IN ASUPERIOR SIX-AXIS TACTILE SENSORY SYSTEM THAT FACILITATES OBJECT GRASPING, MANIPULATION, AND SLIP DETECTION AND CORRECTION. THIS GOAL IS BEING ACHIEVED BY INTEGRATING A ROBUST, SHEAR-FORCE-SENSING CAPABILITY INTO A UNIQUE TACTILESENSING SYSTEM TO PROVIDE SIX-AXIS TACTILE SENSING. NOT INSIGNIFICANTLY, THE SHEAR-FORCE-SENSING SCHEME ALSO DOUBLESTHE NORMAL FORCE SENSITIVITY OF THE TACTILE SENSOR WHILE INCREASING ITS DURABILITY. IN PHASE I, THE USE OF EMBEDDED RETROREFLECTORS IS BEING INVESTIGATED TO PROVIDE A SHEAR-FORCE-SENSING CAPABILITY IN TELEOPERATOR TACTILE SENSORS.