The repertoire of human manipulation is filled with creative use of contacts to move the object about the hand and the environment. However, in most robotic applications the robot fixes all contact points on the object and do grasping. Reliable robot manipulation beyond grasping is still rarely seen.
The difficulties come from the inevitable modeling uncertainties and disturbances in any robotic system. It’s even worse for manipulation systems, because they tend to have multiple possible contact modes. Failure or even physical damage could happen to the execution of a motion plan if the system falls into an unexpected contact mode.
Seeing those difficulties, in this talk I will share our work on robust manipulation by utilizing robot compliance. In the first half I will introduce Hybrid Servoing, a method that computes hybrid force-velocity control to execute a given contact-rich motion plan. In the second half I will introduce Shared Grasping, a geometrical mechanical analysis tool for reliable motion planning. For both methods, we demonstrate repeatable manipulation behaviors in experiments for a variety of problems where grasping is not possible.