World Haptics Conference 2013

Our recent work in the area of model-mediated teleoperation will be presented at this years World Haptics Conference in South Korea.

Title: Dynamic Model Displacement for Model-mediated Teleoperation


In this paper, we study and extend the concept of model-mediated teleoperation (MMT) for teleaction systems which provide live video feedback from the remote side. In MMT, the haptic feed- back is rendered locally at the operator side using a simple object surface model in order to keep the haptic control loop stable in the presence of communication delays. Because the live video from the remote side is received with delay, this results into a visual-haptic asynchrony for the displayed interaction events. In addition, sud- den model parameter updates can lead to “model-jump” effects for the displayed haptic feedback. Both effects degrade the user experi- ence and system performance. To address these issues, we propose a novel approach called model-displaced teleoperation (MDT). In MDT, we adaptively shift the position of the local surface model to delay the haptic contact with the environment, thus compensating the visual-haptic asynchrony and avoiding the model-jump effect. As the haptic feedback is still rendered locally, the advantages of the MMT approach are retained and instabilities in the haptic inter- action are avoided. In our experiments, we determine the percep- tually optimal compromise between visual-haptic asynchrony, the model-jump effect and perceived distance errors and evaluate the subjective experience and objective task performance of the pro- posed MDT and the original MMT for a teleoperation setup with soft objects. Our results show that the users prefer the MDT method compared to MMT once the communication delay between the tele- operator and the operator exceeds 50ms. In addition, the task error rate is reduced by about 50% and the subjects are more capable to control their contact force for system delays larger than 200ms if our MDT method is employed.