"Well, we do what the team tells us to do," station flight engineer Susan Helms replied.
Added Love: "I think thats the right answer, Susan."
NASA managers had considered sending Usachev and Voss outside the station to replace an electronics box that relays computer commands from inside the station to the robot arm.
Engineers initially thought a glitch within the computer unit might have caused the arms wrist joint to freeze up during a May 17 test. But the wrist joint since has been working as advertised, so managers decided that it would not be necessary to replace the so-called arm computer unit.
"We dont see any reason to change hardware on that," Love told the crew.
Still to be resolved: ongoing problems with the arms shoulder joint, which began acting up May 23 when the cranes backup operating systems were being tested.
A software glitch initially was thought to be the cause of that problem, but engineers now suspect that a backup electronics unit on the shoulder joint might have failed. An extensive effort to rectify the problem is continuing.
"Were just scratching the surface on what these issues are, and I know that the folks on the ground are going to give it a lot of attention," Helms told reporters in a space-to-ground interview.
"This is obviously something that needs some attention, and they have been working, I think, around the clock, coming up with solutions."
Considered the centerpiece of Canadas $900 million station contribution, the 57.7-foot (17.5 meter) robot arm is considered crucial to finishing the outpost, which eventually will span an area as large as two American football fields.
Circling some 240 miles (384 kilometers) above Earth, the station now stretches some 171 feet (52 meters) from end to end, and all outpost construction to date has been carried out with 50-foot (15-meter) shuttle robot arms.
The station crane, however, will be required to carry out almost all future construction because the shuttles robot arm is too short to put in place additional outpost labs, skeletal truss segments and solar power panels.
Known as the space station remote manipulator system, the station arm is designed to move end over end to various construction sites outside the outpost, "inchworming" to areas that the shuttles fixed robot arm cannot reach.
Its first big job: mounting a $164 million airlock that will serve as a staging area for spacewalks being carried out at the station when visiting shuttles are not docked at the outpost.
Shaped like a giant genie bottle, the airtight chamber is to be hauled up to the station by shuttle Atlantis on NASAs next outpost construction mission. The flight now is being delayed until early July to give station engineers more time to resolve the problem with the arms shoulder joint.
To that end, engineers from the Canadian Space Agency are developing a software patch that would essentially mask the problem with the shoulder joint when balky backup systems are being used to operate the arm.
The arm so far has been working properly when its primary power, computer control and other systems are being used to operate it.
Usachev and Voss, meanwhile, spent much of the day Friday checking out the Russian spacesuits theyll don for a so-called "internal spacewalk."
Plans call for the pair to don the suits and then enter a spherical section at the end of the stations crew quarters. The job at hand: repositioning a cone-like device that will be used to latch a new Russian docking compartment to the outpost in August or September.
That part of the crew quarters will be depressurized for the job, and while the pair wont venture outside the station, anytime an astronaut or cosmonaut suits up for work in a vacuum, Russian space officials consider the activity a spacewalk.
The internal spacewalk originally was to be conducted by the first resident crew of the international station. It was put off, however, when the planned February launch of the Russian docking compartment was delayed.
The cone-like device to be moved originally served as the receiving end of a drogue-and-probe docking device used to link the Russian Zvezda crew quarters to the stations Zarya space tug. Ultimately, it will be used to dock a Russian-made science power platform to the station.
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