A Decentralized Cooperative Approach to Gentle Human Transportation with Mobile Robots Based on Tactile Feedback

Cooperative transportation of objects by a group of small mobile robots is expected to work in disaster sites. In this study, we aim to transport fragile objects including humans which may move during the transport, with as little burden as possible. We propose the adoption of a flexible tri-axis tactile sensor with thickness at the top of the robot on which the object is mounted for safe support and state monitoring. We improved the leader-follower based control by adding force feedback into the leader’s control law to prevent excessive force on the object, which is the disadvantage of the typical leader-follower method. We verified the robots can transport a rigid body gently with the proposed control law by converging their speeds to the same value in a dynamical simulation and actual experiments. Additionally, we found that multijoint objects also can be transported with the proposed method, whereas the stable support of the object by each robot is reserved for future works.