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Video archive

STS-123 day 3 highlights

This movie shows the highlights from Flight Day 3 as Endeavour docked to the space station.

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STS-123 day 2 highlights

Flight Day 2 of Endeavour's mission focused on heat shield inspections. This movie shows the day's highlights.

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STS-123 day 1 highlights

The highlights from shuttle Endeavour's launch day are packaged into this movie.

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Launching on the shuttle

Video cameras on the boosters and tank, plus a cockpit camera show what the shuttle and its astronauts experience during the trek to space.

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STS-120: In review

The STS-120 crew narrates highlights from its mission that delivered the station's Harmony module and moved the P6 power truss.

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 Mission film

STS-123: TCDT

The STS-123 astronauts complete their countdown dress rehearsal at Kennedy Space Center.

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STS-123: To the pad

Endeavour travels to pad 39A in the overnight hours of Feb. 18 in preparation for liftoff on STS-123.

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Progress docking

The 28th Progress resupply ship launched to the International Space Station successfully docks.

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NASA '09 budget

NASA officials present President Bush's proposed Fiscal Year 2009 budget for the agency.

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Introduction to ATV

Preview the maiden voyage of European's first Automated Transfer Vehicle, named Jules Verne. The craft will deliver cargo to the International Space Station.

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Station repair job

Station commander Peggy Whitson and flight engineer Dan Tani replace a broken solar array drive motor during a 7-hour spacewalk.

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Mercury science

Scientists present imagery and instrument data collected by NASA's MESSENGER spacecraft during its flyby of Mercury.

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Expedition 17 crew

Pre-flight news briefing with the crew members to serve aboard the space station during various stages of Expedition 17.

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Station chief optimistic about Dextre software fix
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: March 13, 2008

Space station Program Manager Mike Suffredini said today he's optimistic a software patch will resolve a timing problem that engineers believe has prevented them from successfully routing power to the Canadian Space Agency's Dextre robot. Similar problems involving an electronic component common to the station's Canadian-built robot arm and its mobile transporter were resolved by similar patches that adjusted when power-up commands sent from the lab's robotic work station timed out.

Suffredini said the patch will be ready for installation Friday morning, after an overnight spacewalk by Richard Linnehan and Garrett Reisman to prepare a Japanese logistics module for attachment to the space station and to begin assembly of the special purpose dextrous manipulator, or SPDM, known affectionately as Dextre. The spacewalk was scheduled to begin at 9:23 p.m.

Dextre was launched disassembled, its arms, hands and central torso bolted to a Spacelab pallet. That pallet was moved from Endeavour's cargo bay and mounted on the station's robot arm transporter earlier today. Tonight's assembly work involves attaching hand-like grippers to each of the robot's 11-foot-long arms.

Without power, engineers will be unable to activate heaters to keep the robot's joints warm. But Suffredini said it would take at least five days without power to cause any problems and that he was confident the problem would be resolved long before then.

"From a time standpoint, we're just not real critical right now," he said.

Engineers believe the power-up problem involves the time needed for commands sent from the station's robotic work station to make their way through three amplifiers, multiple connectors and associated wiring before reaching a device known as a power distribution unit, or PDU, in the robot's torso.

"This PDU is a common component in the SSRMS (station robot arm) system and the mobile servicing system," Suffredini said. "And in fact, in both of those cases we had a timing issue and we went and made a patch to the RWS, the robotic work station, to fix the problem. The problem is, it sends out a command and says 'turn on' and then waits five seconds and starts commanding. If the thing hasn't warmed up and been ready to accept it so it can react, then (the RWS) goes 'oh, you didn't do what I asked you to do so I'm going to stop talking to you.'

"The problem is, all these things are wired differently, they go through a number of connectors, they go through a number of amplifiers. The clock starts ticking when the RWS sends out a command. In this case, it goes through three amplifiers, a bunch of wires, it gets to the PDU, the PDU starts thinking about it and meanwhile, the clock's ticking. At that point if it doesn't react right, the RWS says 'you're sick.'"

Suffredini said telemetry from the Spacelab pallet Dextre's components are mounted on shows the PDU is on and drawing power as expected. The problem, engineers believe, is in the software controlling the robotic work station. If the patch works, the issue will be resolved and the astronauts will press ahead with Dextre asssembly during a second spacewalk overnight Saturday.

In other developments, LeRoy Cain, chairman of NASA's Mission Management Team, told reporters this afternoon that analysis of launch imagery, an inspection of Endeavour's nose cap and wing leading edge panels and a preliminary assessment of the shuttle's heat shield tiles based on photographs shot by the station crew before docking Wednesday night indicate the ship's heat shield is in good shape.

No major problems have been identified and commander Dominic Gorie was told today there is no need for any additional, "focused" inspections. Cain said he expects the MMT to clear the heat shield for re-entry, after a few remaining, relatively minor questions are resolved.

One such open item is a very small depression, or ding, in the carbon composite material around the fitting that helps attach the shuttle's nose to the external fuel tank. Cain said the pit might represent a debris impact, but it is very small and not expected to require any additional attention.

"The team worked through the night, poring over the data from the scans that we get from the orbiter boom system as well as the data from the rendezvous pitch maneuver that we did. All of that data looks really good. The team has determined that we don't need any focused inspection, that is to say, we don't have any areas that we have any concern about that would require us to do a focused inspection."

He said NASA's Debris Assessment Team would continue to examine the data "and we anticipate being able to clear the vehicle for entry within a day or two."

Spaceflight Now Plus
Additional coverage for subscribers:
VIDEO: NARRATED PREVIEW OF SPACEWALK NO. 1 PLAY

VIDEO: THE FLIGHT DAY 3 HIGHLIGHTS MOVIE PLAY
VIDEO: DEXTRE PALLET MOVED FROM SHUTTLE TO STATION PLAY
VIDEO: THURSDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: SHUTTLE ENDEAVOUR DOCKS TO SPACE STATION PLAY
VIDEO: ENDEAVOUR PERFORMS THE 360-DEGREE BACKFLIP PLAY
VIDEO: VIEWS OF THE SHUTTLE APPROACHING FROM BELOW PLAY
VIDEO: NARRATED ANIMATION OF PREVIEWING THE DOCKING PLAY
VIDEO: UPDATE FROM MISSION MANAGEMENT TEAM PLAY

VIDEO: THE FLIGHT DAY 2 HIGHLIGHTS MOVIE PLAY
VIDEO: WEDNESDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: ANIMATION OF THE HEAT SHIELD INSPECTIONS PLAY
VIDEO: NARRATED TOUR OF ENDEAVOUR'S PAYLOAD BAY PLAY

VIDEO: THE FLIGHT DAY 1 HIGHLIGHTS MOVIE PLAY
VIDEO: INSIDE MISSION CONTROL DURING LAUNCH PLAY
VIDEO: THE FULL LAUNCH EXPERIENCE PLAY
VIDEO: SHUTTLE ENDEAVOUR BLASTS OFF! PLAY
VIDEO: THE POST-LAUNCH NEWS CONFERENCE PLAY
VIDEO: HIGHLIGHTS FROM ENDEAVOUR'S LAUNCH CAMPAIGN PLAY
VIDEO: HIGHLIGHTS OF THE PAYLOADS' LAUNCH CAMPAIGN PLAY

VIDEO: LAUNCH REPLAY: VAB ROOF PLAY
VIDEO: LAUNCH REPLAY: PAD FRONT PLAY
VIDEO: LAUNCH REPLAY: PRESS SITE PLAY
VIDEO: LAUNCH REPLAY: WEST TOWER PLAY
VIDEO: LAUNCH REPLAY: PAD PERIMETER PLAY
VIDEO: LAUNCH REPLAY: UCS-23 WIDESCREEN PLAY
VIDEO: LAUNCH REPLAY: CAMERA 009 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 049 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 050 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 051 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 054 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 061 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 063 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 070 PLAY
VIDEO: LAUNCH REPLAY: CAMERA 071 PLAY
VIDEO: LAUNCH REPLAY: CAMERA CS-1 PLAY
VIDEO: LAUNCH REPLAY: CAMERA CS-2 PLAY
VIDEO: LAUNCH REPLAY: CAMERA CS-6 PLAY

VIDEO: FINAL PRE-LAUNCH POLLS GIVE "GO" FOR LIFTOFF PLAY
VIDEO: ENDEAVOUR'S CREW MODULE CLOSED FOR FLIGHT PLAY
VIDEO: ASTRONAUT DOI CLIMBS INTO HIS SEAT PLAY
VIDEO: PILOT JOHNSON CLIMBS INTO HIS SEAT PLAY
VIDEO: ASTRONAUT REISMAN CLIMBS INTO HIS SEAT PLAY
VIDEO: COMMANDER GORIE CLIMBS INTO HIS SEAT PLAY
VIDEO: ASTRONAUTS ARRIVE AT LAUNCH PAD 39A PLAY
VIDEO: CREW DEPARTS QUARTERS FOR LAUNCH PAD PLAY
VIDEO: ASTRONAUTS DON SPACESUITS FOR LAUNCH PLAY
VIDEO: TIME-LAPSE MOVIE OF SUNSET OVER PAD 39A PLAY
VIDEO: MORNING PREPARATIONS AT LAUNCH PAD 39A PLAY
VIDEO: PAD GANTRY RETRACTED FOR LAUNCH PLAY

VIDEO: OVERVIEW BRIEFING ON CANADA'S DEXTRE ROBOT PLAY
VIDEO: OVERVIEW BRIEFING ON JAPAN'S KIBO FACILITIES PLAY
VIDEO: SUNDAY'S COUNTDOWN STATUS BRIEFING PLAY
VIDEO: SATURDAY'S COUNTDOWN STATUS BRIEFING PLAY
VIDEO: CREW ARRIVES AT KENNEDY SPACE CENTER FOR LAUNCH PLAY
VIDEO: FRIDAY'S COUNTDOWN STATUS AND WEATHER BRIEFING PLAY

VIDEO: STS-123 ASTRONAUT BIOGRAPHY MOVIE PLAY
VIDEO: NARRATED SHORT FILM PREVIEW ENDEAVOUR'S FLIGHT PLAY

VIDEO: STS-123 MISSION OVERVIEW BRIEFING PLAY
VIDEO: BRIEFING ON THE SPACEWALKS PLAY
VIDEO: CREW'S PRE-FLIGHT BRIEFING PLAY
VIDEO: SHUTTLE AND ISS PROGRAM UPDATE PLAY

VIDEO: CREW INTERVIEW: COMMANDER DOM GORIE PLAY
VIDEO: CREW INTERVIEW: PILOT GREG JOHNSON PLAY
VIDEO: CREW INTERVIEW: MS1 BOB BEHNKEN PLAY
VIDEO: CREW INTERVIEW: MS2 MIKE FOREMAN PLAY
VIDEO: CREW INTERVIEW: MS3 TAKAO DOI PLAY
VIDEO: CREW INTERVIEW: MS4 RICK LINNEHAN PLAY

VIDEO: FLIGHT READINESS REVIEW NEWS BRIEFING PLAY
VIDEO: TCDT TRAINING HIGHLIGHTS PLAY
VIDEO: PRESS CHAT WITH CREW AT LAUNCH PAD PLAY
VIDEO: CREW ARRIVES AT KSC FOR PRACTICE COUNT PLAY
VIDEO: ENDEAVOUR ARRIVES AT PAD 39A PLAY | XL SIZE
VIDEO: SHUTTLE ROLLS TO THE VAB PLAY | XL SIZE
MORE: STS-123 VIDEO COVERAGE
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