Influences of Network Delay on Cooperative Work between Remote Robots with Force Feedback

In this paper, we deal with cooperative work between two remote robots with force feedback. A user remotely operates the two robots with a haptic interface device. We conduct an experiment of carrying a wooden stick together by the two robots as cooperative work, and we investigate influences of the network delay on the work. The user can feel reaction force which is calculated from force information sensed by a force sensor of each robot though the haptic interface device. Then, we have two calculation methods of reaction force because there are two force sensors. One is calculated from force information sensed by both force sensors, and the other is calculated from force information sensed by only one force sensor. We compare the two calculation methods. Experimental results demonstrate that the force applied to the wooden stick becomes larger as the difference in network delay between the two robots increases. Also, we show that the former method is better than the latter method.