Dextre's Most Dexterous Task: Canadian Space Agency Robot Sets Record for Precision

Dextre, the Canadian Space Agency's robotic handyman on board the International Space Station (ISS), has accomplished the most intricate work ever performed by a robot in space. Over three days (March 7-9), Dextre successfully concluded the initial phases of the Robotic Refueling Mission with unprecedented precision.

Dextre, the Canadian Space Agency's robotic handyman on board the International Space Station (ISS), has accomplished the most intricate work ever performed by a robot in space. Over three days (March 7-9), Dextre successfully concluded the initial phases of the Robotic Refueling Mission with unprecedented precision. A collaboration between NASA and the Canadian Space Agency, the Robotic Refueling Mission was designed to demonstrate the ability of using robots to refuel and service existing satellites in space-especially those not designed for repair. The mission also marks the first time Dextre was used for a technology research and development demonstration on board the Station.


"The Robotic Refueling Mission required surgical precision and Dextre succeeded each task on the first attempt," said Steve MacLean, President of the Canadian Space Agency. "It's the robotic equivalent of threading a needle while standing on the end of a diving board. With thirty years of experience flowing through the iconic Canadarm, Canadarm2 and now Dextre, Canada has honed its skills in space robotics to millimetre precision."

For the Robotic Refueling Mission, NASA's Goddard Space Flight Center designed and built a mock satellite (roughly the size of a washing machine) fitted with various caps, nozzles and valves like those found on satellites. The module contains four specialized tools that Dextre can use to interact with these diverse interfaces. To conclude the initial checkout phase of the mission, Dextre's duties included: retrieving and testing three of the tools to ensure they survived the rigours of launch; releasing seven launch locks that secured four small tool adapters during the module's flight to the Space Station; and then cutting two razor-thin wires fastening valve caps to the module. One of these cuts required the 3.7-metre-high Dextre to slide a tiny hook under a wire with only about a millimetre of clearance-the most precise task ever attempted by Canada's state-of-the-art robot. Operations on board the Space Station were choreographed and coordinated by international ground crews at NASA's Goddard Space Flight Center in Greenbelt, Maryland; Johnson Space Center in Houston, Texas; Marshall Space Flight Center in Huntsville, Alabama; and the Canadian Space Agency's control center in St. Hubert, Quebec.

RRM operations will tentatively resume in May 2012 with the completion of the initial phase. Dextre will be challenged even further in the summer months with the highly anticipated RRM Refueling task, which will require the robot to transfer fuel from one of the RRM tools to a refueling port on the mock satellite.

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ST Robotics Develops the Workspace Sentry for Collaborative Robotics

ST Robotics Develops the Workspace Sentry for Collaborative Robotics

The ST Robotics Workspace Sentry robot and area safety system are based on a small module that sends an infrared beam across the workspace. If the user puts his hand (or any other object) in the workspace, the robot stops using programmable emergency deceleration. Each module has three beams at different angles and the distance a beam reaches is adjustable. Two or more modules can be daisy chained to watch a wider area. "A robot that is tuned to stop on impact may not be safe. Robots where the trip torque can be set at low thresholds are too slow for any practical industrial application. The best system is where the work area has proximity detectors so the robot stops before impact and that is the approach ST Robotics has taken," states President and CEO of ST Robotics David Sands.