A data grid strategy for non-prehensile object transport by a multi-robot system

In this paper, we propose a control strategy for non-prehensile object transport using a multi-robot system. While an object can be unmanageable for a single robot to push and transport, we demonstrate via simulations that a team of cooperative robots can be used to transport such an object. The proposed control strategy is divided into two phases: caging and cooperative transport. In the first phase, the robots start from arbitrary positions and then approach the object to be transported, forming a cage around it. The second phase consists of cooperatively transporting the object ensuring it remains caged during transport. In the proposed strategy, the robots take a decentralized approach where robots behave autonomously while being in indirect communication by leveraging distributed data structures to share their state. Our use of distributed data structures like distributed locks, sets, and maps offered by the data grid concept provides a mechanism for inter-robot communication without development of a new application-specific protocol. To our knowledge, the use of in-memory data grid (IMDG) is new to the field of multi-robot systems. We believe it could provide a promising solution to simplify inter-robot communication. In this paper, we present our design for a coordinated motion control strategy for object transport leveraging IMDG. Finally, we demonstrate our results using a realistic simulator that shows the feasibility of our approach in various environments.