Online Active Safety for Robotic Manipulators

Future manufacturing environments will see an increased need for cooperation between humans and machines. In this paper we propose a method that allows industrial manipulators to safely operate around humans. This approach guarantees that the manipulator will never collide with human operators while performing its normal tasks. This is done in an near-optimal way by considering how forward reachable sets of human operators grow with time, and by continuously updating these reachable sets based on current position estimates of the operators near the robot. An implicit active set invariance filter is then used to constrain the system—in a minimally invasive way—to stay in the complement of that forward reachable set. We demonstrate this approach in simulation on an industrial robotic arm: the ABB IRB 6640.