Freeflying Camera

Near the end of the spacewalk, Scott and Lindsey at last got the chance to test-fly AERCam/Sprint. ''What I'm going to do is retrieve the Sprint from the airlock and I'll make my way up to the foot restraint [and] mount myself in the foot restraint,'' Scott told an interviewer before Columbia lifted off. ''Once I've done that, I'll power it on and look for a sequence of five flashing lights that tells me the power-up went well and everything's working properly. Then, when Steve gives me the 'go', I'll rotate it about one or more axes to perform another self-test. When we get the indication that the self-test is complete, I'll just stand-by. Steve will go through a series of tests and checks from his console [on the flight deck]. When he gives me the word, I'll simply release it, sit back and watch and catch it once the flight is over. He will pilot it back to my location, I'll reach out and grab it, put a tether on it, power it down and that will be the end.''

The first flight of AERCam went like clockwork and, after Lindsey had tested its tiny nitrogen-gas thrusters - which Scott described as a sensation of ''very tiny thumps'' against his spacesuit glove - the $3-million robot beachball was released into the payload bay at 12:15 pm. Spectacular images of Columbia and the blue-and-white Earth were transmitted to Mission Control from its two tiny television cameras and the robot's handling characteristics were so good that Lindsey was granted additional time to evaluate it.

''Steve's just raving about the handling qualities,'' Kregel said at one point. ''He says it's flying just like the simulator.''

''Hey, pretty cool,'' replied Capcom Bill McArthur, as he watched stunning images on his monitor in Mission Control, then suggested, ''Maybe a view a little bit higher looking down at the orbiter could play real well down here.''

After more than an hour of tests, Lindsey gently manoeuvred AERCam/Sprint back towards Scott's gloved hands at 1:27 pm. ''Keep it coming ... another couple of inches,'' he told his joystick-wielding colleague. ''I can feel the thrusters on my glove. Okay, I've got the free-flier!'' Lindsey had nothing but praise for the robot's designers and Harbaugh, too, was more than happy. ''Having this kind of 'floating eyeball' in our hip pocket, available when we need it for space station, is going to be worth its weight in gold over the next few years.''

Cliff Hess was elated, telling journalists that AERCam only used 65% of its onboard nitrogen supply and a mere 8% of the power from its lithium batteries, reaching a maximum distance of about 12 m from Columbia. ''The team is on 'cloud nine' after the wonderful performance that we had with the Sprint,'' he said. ''We think there are some improvements that could be made, as we thought there would be. We need to add more autonomy, to free up the pilot workload, so there's less [work] to actually fly it: more intelligence in the software. We can put on additional sensing in the future, depending on what we use it for, and then I think we'd like to have the capability to deploy and retrieve it without requiring an EVA crew member. We could fly it into something like a [GAS] can that could be mounted on the Shuttle or a station truss. I think it shows what can be done.'' Scott and Doi stowed the robot back in Columbia's airlock and wrapped up the final few tasks of their spacewalk, which officially ended at 4:08 pm.

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