Robot uses on-board tracking to catch balls autonomously

’Rollin’ Justin’, a humanoid robot, was built around two years ago to carry out everyday household tasks requiring fine manipulation. The intention was to use Justin as a research platform to retrofit new abilities — the latest being the catching of two balls simultaneously.

‘It’s not really easy to catch a ball; it’s a dynamic task that takes dexterity,’ Dr Berthold Bäuml told The Engineer.

‘A child takes quite a long time to have this feeling for a ball, especially when two balls are coming at the same time — we have a handball player in the lab who can do this but for others, like me, that’s very hard.’

The robot’s head is equipped with stereo cameras to precisely track the trajectory of the ball in 3D space. Bäuml said that the addition of an inner ear — or inertial measurement unit (IMU) — allows the robot’s head to follow the ball to the hand.