Human-like coordination of body-assisted arm movements for object manipulation

Abstract

Manipulation is an integral capability for service robots. The goal of this thesis is to design and develop an approach that enables a mobile robot to mimic human manipulation abilities. We consider a differential type of mobile robot that is endowed with an arm and gripper. The robot is assumed to have visual sensing so that it can determine the relative position of the object of interest. First, it is observed that hu mans exhibit various basic modes of interaction with an object of interest, including extension, flexion, gripping, release and translation. As such, the robot can be pro grammed to have similar capabilities through establishing the correspondence between the robot and a human with respect to the underlying manipulation mechanisms. More complex behaviors such as putting, pulling, pushing, and shaking are defined using a sequential composition of basic operations. Second, humans are observed to achieve these tasks through the coordination of their body and arm movements. For this, a control approach in which the movements of the robot body and manipulator are cou pled temporally and spatially is proposed. As such, if the object of interest is within the robot’s reach, then only arm movements are made. If this is not the case, the robot starts moving its body. Depending on the vicinity of the object, this may be accom panied by arm motion or not. The control algorithm results in the robot’s body and arm movements to be done in a coupled manner. The proposed approach is evaluated through an extensive set of experiments involving various manipulation tasks.