Toward a task space framework for gesture commanded telemanipulation

This paper introduces a new framework for task space telemanipulation. The TASK space grasping and MANipulation (TaskMan) concept utilizes a library of tasks based on gesture commands, which replaces the conventional mapping required between the human hand and the end effector. Task communication between the human machine interface (HMI) and the robot end effector requires two symbiotic but nonidentical state machines on the master and slave side. The task states on two sides are synchronized via a single channel communication, as opposed to multi-channel joint space or Cartesian mapped information. HAND gesture command for grasping and MANipulation (HandyMan) HMI command algorithm is proposed for the recognition of hand gestures, which incorporates a library of intuitive task gestures to be used by the teleoperator wearing a CyberGlove. The task gestures are used to drive the states of the TaskMan state machines. With the proposed concepts, this work has realized teleoperated grasp and manipulation with a 15-DoF robot hand in task space. Full 6-DoF of object manipulation was achieved with different grasp combinations, and demonstrated higher repeatability, success rate and easier operation compared to conventional joint space teleoperation methods.

I. INTRODUCTION

Remote operation of a multi-finger robotic hand has been traditionally implemented using bilateral control with visual and force feedback, such that the slave receives commands at the robot hand's joint level. Such telemanipulation requires a mapping between the human hand and a robotic hand, as the kinematics and configuration spaces of both hands are in general different. This mapping is done via the joint space, to get similar poses [1], or in the cartesian space, to get similar fingertip positions [2]. A previous evaluation of the performance of a telemanipulation system for space operation showed acceptable performance in grasping tasks, but poor behavior in fine manipulation [3], mainly due to mapping difficulties, human input retrieval limitations, and end-effector performance limitations. Furthermore, these approaches require large numbers of Degrees of Freedom (DoF) command channels, which would not meet the low bandwidth requirements in some applications such as space telerobotics [4].