European Robotic Arm: Europe's grip on the International Space Station

European Robotic Arm: Europe’s Grip on the International Space Station Geert

MENNENGA

The European Robotic Arm (ERA) which is developed by Fokker Space, is a crucial piece of equipment for the Russian segment of the International Space Station. Thanks to ERA, the Astronauts will be able to perform many routine tasks outside the space station without leaving the safety and protection of the module. This intelligent space robot has several unique features - most strikingly is its ability to ‘walk’ around the exterior of the ISS, moving hand-over-hand between fixed base points, and controlling its own movements. Astronauts can control the robot from inside or outside the space station

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he ERA project is developed for the European Space Agency (ESA) by the European space industry with Fokker Space as prime contracter. The robotarm will be launched by an American Space Shuttle to be put to work in space by Russian cosmonauts, international cooperation at its best. (figure 1). The ERA programme comprises the delivery of the flight model, a qualification model, several test models as for example a mock-up for use in a water tank by trainee cosmonauts. Furthermore we

deliver the control software and the advanced simulator system for operational planning, definition of procedures and mission evaluation and cosmonaut/astronaut training purposes.

protected environment of the space station. Work on the space robot started in the eighties, and Fokker Space was the prime contractor from the outset. The ERA as an intelligent robot that consists of two symmetrical carbonfibre arm sections, each about five metres long (figure 2). A hinged joint connects the two ‘arms’. The ‘Wrists’ are fitted with

What is the ERA? The ERA’s role is to reduce to the absolute minimum the sort of work that takes the astronauts outside the

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Figure 1. Artist’s view of the European Robotic Arm. (Dot. Fokker Space B. U)

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Figure 3. The Arm components. (Dot. Fokker Space B. V)

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FIgwe 2. The ERA programmes, created and tested on ground are executed under Extra Vehicular Activity (f VA) or lntra Vehicular Activity (WA) operator system. (Dot. Fokker Space B. V)

clasping devices, the Basic End Effecters,which the ERA usesto hold on to the module.The robotic arm has an intelligent computer systemthat is in constantcontrol of the robot and decides whether a task is physically possible.The systemis able to recognisepositionsand objects.

The ERA canmove aroundthe outside of the module under its own power, using its End Effector to move from BasePoint to BasePoint. The contact betweenthe BasePoint and the Basic its End Effector acts as an interface through which data can be exchanged andenergy supplied.

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The robot is able to operate with unparalleled precision. In space,for example, the ERA is able to move massive objects weighting thousands of kilos with a positional accuracyof better that 3 mm. a

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