NASA's android astronaut assistant prepares for launch

NASA is preparing to send its first humanoid robot into space. Robonaut first twitched to life in September 1999 and, after a decade of tests, the 140-kilogram R2 model will finally be launched to the International Space Station on the space shuttle Discovery's last mission in September.

With continual maintenance work needed on the ISS, the idea is to give the crew an assistant that never tires of undertaking mundane mechanical tasks - initially inside the craft but later outside it too.

R2 comprises a humanoid head and torso with highly dexterous arms and hands. It was developed by NASA in conjunction with roboticists at General Motors. After being bolted to a piece of ISS infrastructure, R2 can use the same tools, such as screwdrivers and wrenches, as the astronauts.

One reason for the mission, NASA says, is to see how Robonaut copes with the cosmic radiation and electromagnetic interference inside the space station.

The main challenge, though, will be to ensure the robot is safe to work with, as tools can fly off easily in microgravity, says Chris Melhuish of the Bristol Robotics Laboratory in the UK. "Robots have to be both physically and behaviourally safe," he says.