How to Capture a Dragon in Space

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With the upcoming historic launch of the SpaceX Dragon capsule to the International Space Station, astronauts in orbit have been getting ready for the first commercial spacecraft that will bring supplies to the station. Astronauts Don Pettit and André Kuipers will be manually capturing and berthing the Dragon capsule, using the ISS’s Canadarm2. Originally, current station commander Dan Burbank was to be the main arm operator, but with the delay in Dragon’s launch (it was originally scheduled for February 2012), Burbank will already be back on Earth by the time Dragon reaches the station, currently scheduled for May 3. So now, Pettit and Kuipers have had to take over the duties and learn their new jobs while in space. Without the high-tech simulators that NASA has at Johnson Space Center, how do the astronauts prepare and practice for this important event?

“We have a really neat capability here on Station,” Pettit said during a press conference last week. “I have it set up all the time, so I wake up in the morning and have a bag of coffee in my mouth and a cinnamon scone in one hand and flying the simulator with the other.”

The crew actually has two ways to practice for Dragon’s arrival.

“One is actually flying (practicing with) the Canadarm, which is the world’s best trainer,” Pettit said, “and then on station we have two space station computers which double as an Arm simulator, and it has a full set of the Arm hand controllers – the setup, which we call Robot allows us to fly track and capture trajectories just as if we were in the simulators in Houston.”

Initially Burbank would have been the main arm officer, with Pettit and Kuipers assisting. Now, Pettit and Kuipers will have to complete the task themselves, with the two of them doing all the things that the three of them were originally trained to do.

For the capture and berthing, Pettit and Kuipers will be in the Cupola, with Pettit as prime operator and Kuipers as second arm operator. “We will have arm operation in the (Destiny) lab as a ‘hot backup’ just in case of contingencies, and we can activate it there if needed.”

The two astronauts will use the Station’s Canadarm2 to first grab the spacecraft and then maneuver it into place to mate with the Harmony module’s Earth-facing docking port.

Pettit said the on-orbit training has been invaluable. “It is really good to have that type of capability,” he said.

The following animation from the Canadian Space Agency shows just how complex it is to capture a Dragon in space.

SpaceX’s launch and Dragon’s arrival will be the premiere test flight in NASA’s new strategy to resupply the ISS with privately developed rockets and cargo carriers under the Commercial Orbital Transportation Services (COTS) initiative. Even though it is technically a est flight, NASA isn’t about to pass up an opportunity to send supplies to the station. Dragon will carry about nearly 521 kg (1,150 pounds) of cargo, mainly food and some spare parts for the ISS. When Dragon departs, the station crew will load nearly 680 kg (1,500 pounds) of cargo to be sent back to Earth, since the Dragon capsule won’t burn up in the atmosphere like other supply ships — it will be recovered in the ocean.

NASA announces Feb. 7 launch for 1st SpaceX Docking to ISS

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Make or break time for NASA’s big bet on commercial space transportation is at last in view. NASA has announced Feb. 7, 2012 as the launch target date for the first attempt by SpaceX to dock the firms Dragon cargo resupply spacecraft to the International Space Station (ISS), pending final safety reviews.

The Feb. 7 flight will be the second of the so-called Commercial Orbital Transportation Services (COTS) demonstration flights to be conducted by Space Exploration Technologies, or SpaceX, under a contact with NASA.

Several months ago SpaceX had requested that the objectives of the next two COTS flights, known as COTS 2 and COTS 3, be merged into one very ambitious flight and allow the Dragon vehicle to actually dock at the ISS instead of only accomplishing a rendezvous test on the next flight and waiting until the third COTS flight to carry out the final docking attempt.

The Dragon will remain attached to the ISS for about one week and astronauts will unload the cargo. Then the spacecraft will depart, re-enter the Earth atmosphere splashdown in the Pacific Ocean off the coast of California.

“The cargo is hundreds of pounds of astronaut provisions,” SpaceX spokeswoman Kirstin Grantham told Universe Today.

SpaceX Dragon approaches the ISS
Astronauts can reach it with the robotic arm and berth it at the Earth facing port of the Harmony node. Illustration: NASA /SpaceX

“SpaceX has made incredible progress over the last several months preparing Dragon for its mission to the space station,” said William Gerstenmaier, NASA’s associate administrator for the Human Exploration and Operations Mission Directorate. “We look forward to a successful mission, which will open up a new era in commercial cargo delivery for this international orbiting laboratory.”

Since the forced retirement of NASA’s Space Shuttle following the final fight with orbiter Atlantis in July 2011 on the STS-135 mission, the US has had absolutely zero capability to launch either supplies or human crews to the massive orbiting complex, which is composed primarily of US components.

In a NASA statement, Gerstenmaier added, “There is still a significant amount of critical work to be completed before launch, but the teams have a sound plan to complete it and are prepared for unexpected challenges. As with all launches, we will adjust the launch date as needed to gain sufficient understanding of test and analysis results to ensure safety and mission success.”

SpaceX lofted the COTS 1 flight a year ago on Dec. 8, 2010 and became the first private company to successfully launch and return a spacecraft from Earth orbit. SpaceX assembled both the Falcon 9 booster rocket and the Dragon cargo vessel from US built components.

An astronaut operating the robot arm aboard the ISS will move Dragon into position at the berthing port where it will be locked in place at the Harmony node. Illustration: NASA /SpaceX

The new demonstration flight is now dubbed COTS 2/3. The objectives include Dragon safely demonstrating all COTS 2 operations in the vicinity of the ISS by conducting check out procedures and a series of rendezvous operations at a distance of approximately two miles and the ability to abort if necessary.

The European ATV and Japanese HTV cargo vessels carried out a similar series of tests during their respective first flights.

After accomplishing all the rendezvous tasks, Dragon will then receive approval to begin the COTS 3 activities, gradually approaching the ISS from below to within a few meters.

Specially trained astronauts working in the Cupola will then reach out and grapple Dragon with the Station’s robotic arm and then maneuver it carefully into place onto the Earth-facing side of the Harmony node. The operations are expected to take several hours.

The COTS Demo 2/3 Dragon spacecraft at Cape Canaveral. Photo: SpaceX

If successful, the Feb. 7 SpaceX demonstration flight will become the first commercial mission to visit the ISS and vindicate the advocates of commercial space transportation who contend that allowing private companies to compete for contracts to provide cargo delivery services to the ISS will result in dramatically reduced costs and risks and increased efficiencies.

The new commercial paradigm would also thereby allow NASA to focus more of its scarce funds on research activities to come up with the next breakthroughs enabling bolder missions to deep space.

If the flight fails, then the future of the ISS could be in serious jeopardy in the medium to long term because there would not be sufficient alternative launch cargo capacity to maintain the research and living requirements for a full crew complement of six residents aboard the orbiting laboratory.

Feb. 7 represents nothing less than ‘High Stakes on the High Frontier’.

NASA is all about bold objectives in space exploration in both the manned and robotic arenas – and that’s perfectly represented by the agencies huge gamble with the commercial cargo and commercial crew initiatives.