Automated Transfer Vehicle
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| Automated Transfer Vehicle | ||
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 Automated Transfer Vehicle - a look at the components |
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| Description | ||
| Role: | supply the International Space Station with propellant, water, air, payload and experiments. | |
| Crew: | unmanned | |
| Dimensions | ||
| Height: | 10.3 m | |
| Diameter: | 4.5 m | |
| Volume: | 9 tons | |
| Performance | ||
| Endurance: | docked with the ISS for six months | |
| Apogee: | 400 km | |
| Perigee: | 300 km | |
| Inclination: | 51.6 degrees | |
The Automated Transfer Vehicle or ATV is an unmanned resupply spacecraft developed by the European Space Agency (ESA)[1]. It is designed to supply the International Space Station with propellant, water, air, payload and experiments. In addition, the ATV can re-boost the station, into a higher orbit, which shrinks over time due to friction with the atmosphere.
The ATV will be launched with an Ariane 5 from Kourou, French Guiana. After approximately two days of flight it will arrive at the International Space Station and dock automatically to the Russian Service Module Zvezda. The first flight of the ATV has been delayed many times and is now scheduled for November 2007.
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[edit] Design
The ATV is designed to complement the Progress spacecraft, having three times its capacity. Like the Progress, it carries both bulk liquids and relatively fragile freight which is stored in a cargo hold kept in a pressurized shirtsleeve environment so that astronauts can have access to it without putting on a spacesuit. The ATV pressurised cargo section is based on the Italian-built Multi-Purpose Logistics Module (MPLM), which is already in service as a Shuttle-carried ‘space barge’ transporting equipment to and from the Station. Also like the Progress, the ATV will additionally serve as a container for the station's waste.
Each ATV weighs 20.7 metric tonnes at launch and has a cargo capacity of 9 metric tonnes:
- 1500 to 5500 kg of dry cargo (re-supply goods, scientific payload, etc.),
- Up to 840 kg of water,
- Up to 100 kg of gas (nitrogen, oxygen, air), with up to two gases per flight,
- Up to 4700 kg of propellant for the re-boost manoeuvre and refueling the station. The ATV propellant used for re-boost (monomethylhydrazine fuel and nitrogen tetroxide oxidizer) is of a different type from the payload Russian refueling propellant (UDMH fuel and N2O4 oxidizer).
After undocking, the ATV is led to a controlled burn-up in the atmosphere, along with up to 6.5 metric tonnes of waste.
[edit] Development
The prime contractor for the ATV is EADS Astrium Space Transportation, leading a consortium of many sub-contractors. The prime contractor office is currently located in Les Mureaux, France, and will be transferred to Bremen, Germany, once the development is completed and the production of the six initial units starts. In order to facilitate the relationship between the contractor and ESA, an integrated ESA team at the Les Mureaux site has been established for the duration of the development.
The first ATV, whose construction is now complete, is expected to be launched during the second half of 2007. Contracts and accords have been signed for six more ATVs, which should be launched about once every year.[citation needed] The Jules Verne is the first of five ATVs.[2] Astrium Space Transportation will build these six ATVs in its facility in Bremen, where the Jules Verne has already been assembled.
To this end, RSC Energia has signed a 40 million euro contract with one of the main subcontractors of EADS Astrium Space Transportation, the Italian company Alenia Spazio, to supply the Russian Docking System, refuelling system, and Russian Equipment Control System. Within the EADS Astrium Space Transportation led project, Alenia Spazio is in charge of the pressurized cargo carrier of the ATV. These pressurized cargo carriers are produced in Turin, Italy.
[edit] Missions
[edit] Jules Verne
The first flight of the ATV is scheduled for November 2007. It is named Jules Verne, in memory of the first science fiction writer of modern times.
The craft is launched into a 300-km orbit atop an Ariane 5 from the French Guiana ELA-3 equatorial launch site. After the ATV separates from the Ariane rocket, navigation systems are activated and thrusters fire to boost the ATV into the transfer orbit to the ISS.
After three days of orbit adjustments, the ATV will be about 30 km behind and 5 km below the Station. The ship's computers begin final approach manoeuvres over the next two orbits.
The actual docking will be fully automatic. If there are any last-minute problems, a pre-programmed sequence of anti-collision manoeuvres, fully independent of the main navigation system, can be activated.
With the ATV docked, the Station's crew enter the cargo section and remove the payload. The ATV's liquid tanks will be connected to the Station's plumbing and discharge their contents. The Station crew will manually release air components directly into the ISS’s atmosphere. For up to six months, the ATV, mostly in dormant mode, will remain attached to the ISS with the hatch remaining open. The crew will steadily fill the cargo section with the Station's waste. At intervals of 10 to 45 days, the ATV’s thrusters will be used to boost the Station's altitude.
Once its mission is accomplished, the ATV, filled with waste, will be separated. Its thrusters will de-orbit the spacecraft on a steep flight path to perform a controlled destructive re-entry high above the Pacific Ocean.
[edit] Abandoned ATV Evolution projects
The European Space Agency was studying potential evolutions and adaptations of the ATV, following the decision by NASA to retire the Space Shuttle around 2010. These evolutions have now all been dropped.
Most of the studies were focused on the adaptation of the ATV in order to allow cargo return to Earth's surface.
A first study was called PARES (PAyload REtrieval System), and would have included a small ballistic capsule similar to VBK-Raduga and embedded into the ATV docking interface, which would have brought back a few tens of kilograms of payload. PARES could have featured a deployable heat shield system. The European Space Agency was also proposing the system for use with the Progress spacecraft and the H-II Transfer Vehicle (HTV).
The CARV (Cargo Ascent and Return Vehicle) study was investigating a larger lifting capsule, capable of bringing back a few metric tonnes of payload, which could have been installed in place of the ATV pressurized cargo hold.
Such vehicles could have been available by 2010. However, the financial situation of ESA led to a priority given to PARES over the CARV. But finally, the PARES was not proposed by ESA for approval at the latest Ministerial conference of ESA.
Possibility of launch of the ATV on other launchers than Ariane 5 have also be investigated, in particular in the frame of COTS, but NASA chose to go for a US-only solution.
[edit] Notes
- ^ Automated Transfer Vehicle, ESA document EUC-ESA-FSH-003 Rev 1.2 (specification) [1] PDF, accessed 26 March 2007
- ^ Worldwide Testing And ISS Traffic Push ATV Launch To Autumn 2007. SpaceDaily.
[edit] See also
- H-II Transfer Vehicle - similar Vehicle by the Japan Aerospace Exploration Agency (JAXA)
- Commercial Orbital Transportation Services - NASA initiative to create a commercial cargo and crew transportation capability to and from the ISS
- Progress spacecraft - Spacecraft by the Russian Space Agency Roskosmos
- Soyuz spacecraft - Spacecraft by the Russian Space Agency Roskosmos
[edit] External links
- ESA's description of the ATV
- Space.com's Progress Made for Launch of Europe's Delayed ATV
- Alenia Spazio to build 6 ATVs
- ATV Integrated Cargo Carrier
- First ICC
- ATV spacecraft subassembly
- European companies working on ATV
- ESA: ATV Evolution Scenarios
| Unmanned resupply spacecraft |  |
|---|---|
| Progress spacecraft | TKS spacecraft | Automated Transfer Vehicle | H-II Transfer Vehicle |
