Sensitive Manipulation: Manipulation Through Tactile Feedback

Object grasping and manipulation in robotics has been largely approached using visual feedback. Human studies on the other hand have demonstrated the importance of tactile and force feedback to guide the interaction between the fingers and the objects. Inspired by these observations we propose an approach that consists in guiding a robot’s actions mainly by tactile feedback, with remote sensing such as vision, used only as a complement. Directly sensing the interaction forces between the object, the environment, and the robot’s hand enables it to obtain information relevant to the task that can be used to perform it more reliably. This approach (that we call Sensitive Manipulation) requires important changes in the hardware and in the way the robot is programmed. At the hardware level we exploit compliant actuators and novel sensors that allow to safely interact and detect the environment. We developed strategies to perform manipulation tasks that take advantage of these new sensing and actuation capabilities. In this paper we demonstrate that using these strategies the humanoid robot Obrero can safely find, reach and grab unknown objects that are neither held in place by a fixture nor placed in a specific orientation. The robot can also make insertions by “feeling” the hole without specialized mechanisms such as a remote center of compliance.