Visual Feedback for Haptic Assisted Teleoperation of an Industrial Robot

Abstract

Haptic assistance (HA) has been shown to be useful in a wide variety of applications by providing the benefits of automation while keeping the human in the loop. In recent years, providing additional visual feedback has been found to provide benefits to HA interfaces by complementing their advantages and mitigating their weaknesses. However, the implementation and understanding of this interaction are still quite limited. In this study, we provide new insights into this interaction by extending these findings to the HA teleoperation of an industrial robot, in which the HA is comprised of a set of Virtual Fixtures (VFs). Two methods of providing additional visual feedback are implemented for the use case of dross removal and are evaluated in a human factors experiment. The first method is the implementation of a set of visual cues, designed to complement the HA and force feedback. The second method is the use of a head-mounted display (HMD), instead of a desktop monitor, providing additional depth information and an increased sense of immersion. Both methods proved to be beneficial, but only in certain aspects of the operation. The visual cues were found to significantly improve safety in terms of peak collision force, whereas the HMD significantly improves the performance. Additional analysis suggests the use of an HMD causes improvements in the manipulability of the interface. Furthermore, improved scores in the van der Laan questionnaires and the user preference indicate an increased user acceptance due to the implementation of either of the methods. This study provides additional insight into the importance of visual feedback for HA and provides two methods to take advantage of its potential benefits in the teleoperation of an industrial robot.