Mighty Mouse, or M2, earned its heroic name by saving the day at the White Sands Missile Range in southern New Mexico when a radioactive cylinder became jammed inside a metal sleeve. Its radiation field was far too dangerous for a human, even in a protective suit, to get near enough to free it. The White Sands team knew they needed a robot for the job and called Sandia’s High Consequence, Automation, & Robotics (HCAR) team.
Typically the cylinder moved back and forth within the metal sleeve, driven by forced air. From a safe distance, technicians tried to free the cylinder by increasing the air pressure. It turned out the cylinder hit a signal switch in the metal sleeve’s pathway and the increased pressure lodged it securely in place.
Fortunately, gamma rays decrease in intensity through distance. Past a few hundred feet the surrounding area was completely safe. Unfortunately, the lab was shut down and had to be guarded around the clock for safety reasons.
White Sands needed a robot that could withstand high level radiation long enough to dislodge the cylinder and send it back to its storage position. It needed dexterity to maneuver into the lab, drill through a protective plate, and move or remove the signal switch.
Radiation that can kill a human also can kill a robot’s electronics. It was estimated that M2 could withstand intense radiation for only about 50 minutes.
Sandia robotics engineers built the tools needed for the task, practiced, and then deployed to White Sands. M2 successfully removed the switch and returned the cylinder to its resting place after more than five hours in the lab, spread out over four days to allow for repairs. It endured the radiation much longer than expected. M2 entered the lab multiple times and completed various tasks: moving a 1500-lb. radiation shield, selecting and tugging on individual wires within a cable bundle, drilling multiple holes through a stainless steel plate, and removing both socket head and flat head screws.
M2 was 5ft long and weighed 600 lbs. Its arm structure and control system made it uniquely suited to address this problem. Additional features:
- precision motion, extended reach, and a dexterous wrist to reach into awkward places and apply force to drills and screwdrivers
- rapid tool change-out capability needed for accessing and freeing the cylinder
- high-quality zoom cameras, able to monitor the operation from a distance
- position memory, important in starting with tools at the right height and depth
M2 was designed through a teaming partnership with industry as research platform with a goal to serve as a proof-of-concept bomb-disabling unit, and can be used to support a variety of applications.
Read the full news release for more information.