Model predictive control under hard collision avoidance constraints for a robotic arm

Code HAL Paper
  • 1 LAAS-CNRS, Université de Toulouse, Toulouse, France
  • 2 Artificial and Natural Intelligence Toulouse Institute, Toulouse, France
  • 3 Continental, Toulouse, France
  • 4 MiM - Machines in Motion Laboratory, New York University, USA
  • 5 CIIRC - Czech Institute of Informatics, Robotics and Cybernetics, Prague

Abstract

We design a method to control the motion of a manipulator robot while strictly enforcing collision avoidance in a dynamic obstacle field. We rely on model predictive control while formulating collision avoidance as a hard constraint. We express the constraint as the requirement for a signed distance function to be positive between pairs of strictly convex objects. Among various formulations, we provide a suitable definition for this signed distance and for the analytical derivatives needed by the numerical solver to enforce the constraint. The method is completely implemented on a manipulator “Panda” robot, and the efficient open-source implementation is provided along with the paper. We experimentally demonstrate the efficiency of our approach by performing dynamic tasks in an obstacle field while reacting to non-modeled perturbations.