Assistive grasping in teleoperation using infra-red proximity sensors

Abstract

Teleoperated grasping requires the abilities to follow the intended trajectory from the user and autonomously search for a suitable pre-grasp pose relative to the object of interest. Challenges include dealing with uncertainty due to the noise of teleoperator, human elements and calibration errors in the sensors. To address these challenges, an effective and robust algorithm is introduced to assist grasping during teleoperation. Although without premature object contact or regrasping strategies, the algorithm enable the robot to perform online adjustments to reach a pre-grasp pose for a final grasping. We use three infra-red (IR) sensors that are mounted on the robot hand, and design an algorithm that controls the robot hand to grasp objects using the information from the sensors readings and the interface component. Finally, a series of experiments demonstrate that the system is robust when grasping a wide range of objects and even tracks mobile objects. Empirical data from a 5-subject user study allows us to tune the relative contributions from the IR sensors and the interface component, so as to achieve a balance of grasp assistance and teleoperation. © 2013 IEEE.