A third spacewalk is scheduled for today, after a second spacewalk saw most of Dextre installed and tested, overcoming fears that the device might have to be repackaged. The Canadian space robot has been hit by a design flaw which prevented it from being properly powered through a temporary cable, but after it was bypassed everything worked as expected.

The painstaking testing, last night, of each of the seven joints of each arm has revealed only one minor problem with a braking system, which will have little consequence over the actual performance of the device. “I guess I have to say it — it’s alive!” said Pierre Jean, the acting head of the Canadian space station program.

Tonight astronauts will add a tool holster and other accouterments for Dextre. It will be a walk in the park compared to the previous one, in which Richard Linnehan and Michael Foreman had to use a pry bar and brute force to free one of the arms from the transport bed where it was latched down for launch. During the second spacewalk which lasted 7-hour, 8-minutes, the two Mission Specialists assembled the stick-figure-shaped Dextre, also known as the Special Purpose Dextrous Manipulator (SPDM), a task that included attaching its two arms.

Dextre is the third and final component of the Mobile Servicing System developed by Canada for the ISS. With advanced stabilization and handling capabilities, Dextre can perform delicate human-scale tasks such as removing and replacing small exterior components. Operated by crew members inside the station or by flight controllers on the ground, it also is equipped with lights, video equipment, a stowage platform, and three robotic tools.

The technology behind Dextre evolved from its famous predecessor Canadarm2. Dextre is the world’s first on-orbit servicing robot with an operational mission, and it lays the foundation for future satellite servicing and space exploration capabilities.

While one arm is used to anchor and stabilize the system, the other can perform fine manipulation tasks such as removing and replacing station components, opening and closing covers, and deploying or retracting mechanisms. To grab objects, Dextre has special grippers with built-in socket wrench, camera, and lights.

The two pan/tilt cameras below its rotating torso provide operators with additional views of the work area. Currently, astronauts execute many tasks that can only be performed during long, arduous, and potentially dangerous spacewalks. Delivery of this element increases crew safety and reduces the amount of time that astronauts must spend outside the station or routine maintenance. Some of the many tasks Dextre will perform include: installing and removing small payloads such as batteries, power switching units, and computers, providing power to payloads, manipulating, installing, and removing scientific payloads.

Designed for station maintenance and service, Dextre is capable of sensing forces and movement of objects it is manipulating. It can automatically compensate for those forces and movements to ensure an object is moved smoothly.

Two more spacewalks are scheduled, both of which will focus on repairing the shuttle’s delicate heat-shield tiles in space and inspecting the malfunctioning joint which was supposed to rotate one of the solar panels on the ISS to face the sun.