Space Station's New Robot in Good Shape After Tests

STS-123 Mission Updates: Part 1
A camera on the exterior of the International Space Station observes Canada's two-armed Dextre maintenance robot. (Image credit: NASA TV.)

This story was updated at 1:37 a.m. EDT March 17.

HOUSTON - Anew mechanical handyman perched outside the International Space Station (ISS)is in fine shape after a Sunday health check-up as astronauts prepare tocomplete its assembly in a spacewalk, mission managers said.

Astronautsinside the station remotely tested the brakes in the arm joints of Canada?s massiveDextre maintenance robot and geared up for a Monday spacewalk to attach itstool belt and other hardware.

?It was agood day,? said Pierre Jean, acting ISS program manager for the Canadian SpaceAgency, which built the two-armed Dextre robot.

Jean saidDextre easily passed each of its electronic systems checks, with all but one of14 intricate joints passing brake tests earlier today. The brake on a wristpitch joint at the end of the robot?s 11-foot (3.4-meter) left arm slippedslightly more than the general acceptable limit, but the glitch is not expectedto be a lasting concern.

?This issomething that we?re very confident that is not going to be an issue,? Jeansaid in a briefing here at NASA?s Johnson Space Center.

The 12-foot(3.7-meter) tall Dextre (pronounced ?Dexter?) weighs 3,440 pounds (1,560 kilograms)and sports two, dexterous hands designed to replace the role of a spacewalkingastronaut on simple fix-it jobs outside the space station. The more than $200-millionrobot is Canada?s third major contribution to the ISS and joins theCanadian-built Canadarm2 arm and a Mobile Base System for the roboticappendages.

Endeavourshuttle astronautsattached Dextre?s arms during a Saturday spacewalk after an earlierexcursion to attach hands to each of the limbs. Commanded by veteran spaceflyerDominic Gorie, Endeavour?s STS-123 crew is in the midst of 16-day mission todeliver Dextre, the firstpiece of Japan?s three-segment Kibo laboratory and spare parts to the ISS overthe course of five spacewalks.

Earliertoday, newly arrived ISS flight engineer Garrett Reisman and shuttle astronautRobert Behnken put Dextre through its meticulous brake tests, moving the sevenjoints on each of the robot?s arms in tiny increments.

?We?re just jumping the gun having fun moving the arms,? Reisman told Mission Control. ?It was reallyneat for us to see [Dextre] come to life.?

Reisman arrivedat the station aboard Endeavour last week and will stay aboard to relieve Frenchastronaut Leopold Eyharts as a member of the station?s Expedition 16 crew. Eyhartswill return to Earth with Endeavour?s STS-123 crew on March 26.

Behnken andfellow spacewalker Rick Linnehan will attach more pieces to Dextre during a Mondayspacewalk, the third of five planned for the STS-123 mission, which willinclude the addition of a tool carrier, a spare parts platform and the removalof several thermal covers. The robot has fully recoveredfrom a power glitch, since traced to a faulty cable on its carrierplatform, which delayed its activation last week. The hefty repair robot hasgained the nickname ?Mr. Dextre? from its flesh-and-blood astronaut crewmates.

?We?veworked on Dextre for about 10 years now,? said Jean, adding that the station?s Canadarm2is still referred to as ?it.? ?I guess as we started treating it like one of thegang. Dextre has become kind of an entity.?

NASA isbroadcasting Endeavour's STS-123 mission live on NASA TV. Click here for'sshuttle mission coverage and NASA TV feed.


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Tariq Malik

Tariq is the Editor-in-Chief of and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. In October 2022, Tariq received the Harry Kolcum Award for excellence in space reporting from the National Space Club Florida Committee. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. You can find Tariq at and as the co-host to the This Week In Space podcast with space historian Rod Pyle on the TWiT network. To see his latest project, you can follow Tariq on Twitter @tariqjmalik.