The Advantage of Compliant Arms

In December, we completed our first milestone, where a PR2 alpha robot without arms autonomously navigated throughout Willow Garage. Our next milestone takes us beyond controlling the robot base to tasks that require the arms, To successfully complete our second milestone, PR2 needs to open doors to enter rooms, and plug itself into an outlet when the battery level gets too low. This requires a fully integrated system, where both the base and the arms work together.

This video shows how PR2''s arms are designed to interact with the environment: both arm are fully compliant and force controlled. When opening a door or a refrigerator, the robot 'feels' the door motion, and follows this motion without exerting high forces on the door handle.  Although the robot tasks in this  video are teleoperated, we are making good progress toward fully autonomous door opening (preview) and autonomous plugging in.  Stay tuned for details.