Dual Arm Work Platform Teleoperated Robotics System

Category: Dismantlement > Heavy Equipment > Robotic System
Reference # : OST No 1787 , DOE/EM-0389 Model No : DAWP-1787

The Dual Arm Work Platform (DAWP) system was used to perform mechanical dismantlement of the radioactive reactor and bio-shield structures. The DAWP manipulated standard, commercially available tools (i.e., circular saws, jackhammers, etc) using two Schilling Titan III hydraulic, teleoperated manipulator arms that were controlled from a remote location. At the CP-5 reactor facility, the two arms were mounted to a steel work platform (DAWP) designed to hold the associated tooling, utilities, and cameras supporting the operation of the manipulator arms and providing a sturdy base for lifting the assembly into the reactor assembly using the facility's polar crane. Once positioned, the system segmented, dismantled and moved the radioactive material to a transfer canister. The Titan III manipulator arms are made from titanium and stainless steel. The arms provide six degrees-of-freedom and are powered by a 3000-psi hydraulic system. Each arm is capable of lifting 240 lbs. The grippers on the arms are capable of exerting a 1000 lb. crushing force and a rotational torque of 75 lb-ft.Various power tools were specially adapted for use with the manipulator arms. The tools ranged from crowbars to sophisticated saws that have built-in oil cooling systems and were operated from the control panel.

Benefits

Reduced personnel exposure to radiation. The system showed it could perform extremely delicate and intricate operations. DAWP is quite efficient in reducing the complexity down to a well-managed, concise operating structure. One operator working in an adjacent control room typically controlled the DAWP. In this way, personnel could maintain a safe distance from the radiation. Can be mounted on deployment devices such as Rosie-C, overhead cranes, telescoping booms, and remote vehicles. Remote operation removes workers from high-radiation environments, supporting ALARA principles. Accepts a variety of tooling configurations including oxy-gasoline torch, router, reciprocating saw, and electrical impact hammer. Operator control and remote viewing capabilities have been integrated with the Rosie-C audio/video capabilities.

Limitations

Although the DAWP is a viable tool, it is not a commercially available product at this time. The water-glycol used as hydraulic fluid is corrosive to electrical connections internal to the manipulator. Setup time and complexity were considerable to control trailer for the operator station. Environmentally sealed electrical connectors were used for electrical tool connection to the base platform in order to exclude contamination from the system. The cameras used to permit greater field of view coverage had some problems with glare and bloom due to the lighting in the reactor shell and also had some mechanical failures in the motorized lenses. Control tether management is one of the most difficult and critical aspects of this technology. The water-glycol used as hydraulic fluid is corrosive to electrical connections internal to the manipulator. The initial costs are high and the cost of operation can vary widely.

Comments

The development of the Dual Arm Work Platform included a consortium of national laboratories and industry manufacturers. Individual components and subassemblies were purchased from or provided by Schilling Robotics Systems, Redzone Robotics Inc., Oak Ridge National Laboratory, the Idaho National Environmental and Engineering Laboratory and Sandia National Laboratory.

Pictures

	DAWP Console
	Close-up view of the DAWP
	Dual Arm Work Platform

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