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The Automated Transfer Vehicle or ATV is an expendable, unmanned resupply spacecraft developed by the European Space Agency (ESA). ATVs are designed to supply the International Space Station (ISS) with propellant, water, air, payload and experiments. In addition, ATVs can reboost the station into a higher orbit.

The first ATV, Jules Verne, was launched in March 2008 and ESA has already contracted suppliers to produce four more to be flown until 2015. A total of seven ATVs could eventually be launched to the International Space Station, mission managers said. Approximately €1.35 billion EUR was spent by ESA on the ATV programme.

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 shirt sleeve environment so that astronauts can have access to it without putting on a spacesuit. The ATV pressurized 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.

The ATV docking system consists of two videometers and two telegoniometers built by Sodern, a subsidiary of EADS. Additional monitoring data is supplied by a redundant Russian-made antenna built for the Ukrainian-built Kurs, an automatic docking system similar to those used on Soyuz manned ferries and on the Progress re-supply ship. Visual imagery is provided by a camera on the Zvezda module.

Also like the Progress, the ATV will additionally serve as a container for the station's waste.

Each ATV weighs 20.7 tonnes at launch and has a cargo capacity of 8 tonnes:

• 1,500 kilograms (3,300 lb) to 5,500 kilograms (12,000 lb) of dry cargo (re-supply goods, scientific payload, etc.),
• Up to 840 kilograms (1,900 lb) of water,
• Up to 100 kilograms (220 lb) of gas (nitrogen, oxygen, air), with up to two gases per flight,
• Up to 4,700 kilograms (10,000 lb) of propellant for the re-boost maneuver and refueling the station. The ATV propellant used for re-boost (monomethylhydrazine fuel and N₂O₄ oxidizer) is of a different type from the payload Russian refueling propellant (UDMH fuel and N₂O₄ oxidizer).

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 four 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 arrived at the ESA spaceport in Kourou, French Guiana on 31 July 2007 after a nearly two week journey from Rotterdam harbour and was launched on 9 March 2008. The Jules Verne was the first ATV to be launched. EADS Astrium Space Transportation builds the ATVs in its facility in Bremen. Contracts and accords were signed in 2004 for four more ATVs, which should be launched about once every two years, bringing the total order, including Jules-Verne, to five.

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 (now Thales Alenia Space), to supply the Russian Docking System, refuelling system, and Russian Equipment Control System. Within the EADS Astrium Space Transportation led project, Thales Alenia Space is in charge of the pressurized cargo carrier of the ATV. These pressurized cargo carriers are produced in Turin, Italy.

In addition to its use by ESA and Russia, the ATV was in the running to service NASA under the Commercial Orbital Transportation Services program. Under the proposal, a joint venture between EADS and Boeing, an ATV would be launched from Cape Canaveral, Florida, using a Delta IV rocket. Ultimately, it was not awarded a contract.

Use

ATV Jules Verne as it re-enters Earth's atmosphere in a controlled burn-up after undocking from ISS.

ATVs are intended to be launched every 17 months in order to resupply the International Space Station. They use GPS and a star tracker to automatically rendezvous with the Space Station. At a distance of 249 m, the ATV computers use videometer and telegoniometer data for final approach and docking manoeuvres. The actual docking to Zvezda is 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 by the flight engineers aboard the station.

With the ATV docked, the station crew enters the cargo section and removes the payload. The ATV's liquid tanks are connected to the station's plumbing and discharge their contents. The station crew manually releases air components directly into the ISS’s atmosphere. For up to six months, the ATV, mostly in dormant mode, remains attached to the ISS with the hatch remaining open. The crew then steadily fills the cargo section with the station's waste. At intervals of 10 to 45 days, the ATV’s thrusters are used to boost the station's altitude.

Once its mission is accomplished, the ATV, filled with up to 6.5 tonnes of waste, separates. Its thrusters move the spacecraft out of orbit (de-orbit) and place it on a steep flight path to perform a controlled destructive re-entry high above the Pacific Ocean.

Scheduled missions

Jules Verne Automated Transfer Vehicle approaches the International Space Station on Monday, 31 March 2008

Jules Verne

The first flight of the ATV was delayed many times before its launch on 9 March 2008. It was named Jules Verne, in memory of the first science fiction writer of modern times, and carried two of the author's original handwritten manuscripts, to be received by the ISS crew as symbolic tokens of the success of the first flight.

The craft was launched into a 300-kilometre (190 mi) orbit atop an Ariane 5 from the equatorial ELA-3 launch site at the Guiana Space Centre. The ATV separated from the Ariane rocket and after weeks of tests and orbit adjustments successfully docked in the International Space Station at 14:45 UTC on 3 April 2008.

ATV Control Centre

ATV missions are monitored and controlled from the ATV Control Centre (ATV-CC) located at the Toulouse Space Centre (CST) in Toulouse, France. The centre is responsible for all planning and executing of every orbital maneuver and mission task of the ATV, from the moment of separation from its launch vehicle, until it burns up in the Earth's atmosphere. The centre has a direct communication line with the Columbus Control Center (Col-CC) in Oberpfaffenhofen, Germany. Col-CC provides ATV-CC with access to both the American TDRSS and the European Artemis communication networks in order to communicate with ATV and the space station. ATV-CC will coordinate its actions with NASA's Mission Control Center (MCC-H) in Houston and the Russian FKA Mission Control Center (TsUP or MCC-M) in Moscow, Russia as well as the ATV launch site at the Guiana Space Centre in Kourou, French Guiana.

ATV Evolution projects

An MSS could be used as a small orbital lab

Following the decision by NASA to retire the Space Shuttle around 2010, the European Space Agency launched a series of studies to determine the potential for evolutions and adaptations of the ATV. Following these studies the cargo return version has now become a serious candidate for development. The goal of this cargo return version beyond giving Europe the capability of bringing scientific data and cargo back to earth is to enhance it further into a man rated version. Though adaptations to the Ariane 5 would be necessary, target dates of 2020 are being considered for achieving manned space flight by Europe.

Mini Space Station

The MSS concept is an ATV evolution proposal under consideration for the future. It proposes multiple ATVs with two docking ports, one at each end. The current version of the ATV is already prepared for a docking port at the back, with the main propulsion system arranged in a cylindrical fashion leaving room for a tunnel through the middle. This concept would allow Soyuz, Progress and other ATVs to dock to the back of the ATV, allowing a steady flow of Russian vehicles using the available docking ports whilst an ATV is docked for an average of around 6 months at a time.

PARES capsules would be able to hold a few kg of cargo

Payload Retrieval System

The PARES would have included a small ballistic capsule similar to VBK-Raduga 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).

CARV would be used to transport a large amount of cargo to Earth.

Cargo Ascent and Return Vehicle

The CARV study investigated a larger lifting capsule, capable of bringing back a few tonnes of payload, which could have been installed in place of the ATV pressurized cargo hold. In addition, a goal was to allow CARV to dock at the US side of the station. Given the larger docking ports there, it would be possible to transfer complete International Standard Payload Racks (ISPRs) from the ATV to the station, which is not possible now. Such vehicles could have been available by 2010. However, the financial situation of ESA led to a priority given to PARES over the CARV. In the end, PARES was not proposed by ESA for approval at the latest Ministerial conference of ESA.

Crew Transport Vehicle

This was another option under consideration. Similar to the CARV variant, this would replace the current Integrated Cargo Carrier with a pressurized re-entry capsule. A significant difference with the cargo-only variant would be the presence of a Crew Escape System, consisting of a number of booster rockets able to pull the crew capsule away from the launcher and/or Service Module in the event of an emergency. The CTV variant of the ATV would be able to seat 4 or 5 crew.

Possibilities for launching of the ATV on other launchers than the Ariane 5 have also been investigated, in particular in the frame of Commercial Orbital Transportation Services, but NASA has meanwhile chosen to go for a US-only solution.

Proposed crewed version

A 3D rendering of the proposed ATV derived manned transportation system.

The aerospace company EADS Astrium and the German Space Agency (the DLR), announced on 14 May 2008 that they would pursue a project to adapt the ATV into a crew transportation system. The craft would be able to launch a 3 man crew beyond LEO via use of a modified version of the Ariane 5 rocket and would be more spacious than the Russian Soyuz. A mock-up of the proposed craft was shown at the 2008 International Aerospace Exhibition in Berlin. If the project is given ESA approval development will proceed in two stages:

• The first stage would see the development of an Advanced Return Vehicle (ARV) capable of transporting up to 1,500kg of cargo from space to earth safely (see CARV above) by 2015. This capability would be available to ESA even if further development were to be halted. It would prove useful in the ISS program as well as the proposed Mars Sample Return Mission with NASA. ARV development would make use of work done on the Atmospheric Reentry Demonstrator, Crew Return Vehicle and related projects. The budget for this stage of the ATV overhaul would reportedly be €300 million.
• The second stage would adapt the then existing capsule to be able to transport people safely as well as upgrade the propulsion and other systems in the service module and would last 4 to 5 years (till 2020) at a cost of "a couple of billion (€)" according to a senior Astrium representative.

Both ESA and EADS Astrium are also involved in the Crew Space Transportation System development program along with JAXA and the Russian Federal Space Agency. Though ESA's head of the future transport and infrastructure division, Marco Caporicci, has denied that the manned ATV evolutions project is an alternative to the CSTS, it is unlikely that ESA will pursue both projects.

In November 2008, the ESA budgeted for a feasibility study into developing a re-entry capsule for the ATV, a requirement for developing a manned version.

See also

• H-II Transfer Vehicle – a similar ISS cargo vehicle being developed by the Japan Aerospace Exploration Agency (JAXA), first flight scheduled for 2009.
• Commercial Orbital Transportation Services – NASA initiative to create a commercial cargo and crew transportation capability to and from the ISS.
• Cygnus spacecraft - an unmanned US cargo and resupply vehicle currently being developed by the COTS NASA initiative. It is expected to be operational in 2010.
• Progress spacecraft – Cargo spacecraft currently operated by the Russian Federal Space Agency Roskosmos.
• CSTS

External links

• Automated Transfer Vehicle, Rev 1.2 PDF - ESA
• ESA's description of the ATV
• ESA's ATV operations page
• ATV press kit by EADS Astrium
• 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
• BBC article about the ATV
• ESA ATV rendezvous and docking Infokit
• Europe could get manned spaceship

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Published in July 2009.

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