A Formation Control Algorithm by Modified Next-state Approximation to Reduce Communication Requirements in Multirobot Systems

Abstract

Multiple robot systems are employed in various applications to get the complex tasks carried out by a group of robots. When Autonomous Underwater Vehicles (AUVs) are employed for underwater missions, they provide higher quality data, more coverage and reduces the mission time, thus resulting in huge cost savings. However, the formation control of such robots depends to a great extent on the communication requirements between the robots. In this paper, we propose a modified next-state approximation algorithm to control the leader follower formation of multiple AUV's which reduces the communication requirements. The controller drives each follower robot to the next desired position by eliminating the error between the next actual position of follower AUV, computed by considering its current and previous position and its next desired position by using a PID controller. Since this algorithm is independent of time step between states, the amount of information to be transmitted can be reduced by increasing the time steps. The design of the formation controller and its simulation studies for a group of AUVs are presented. The results confirm that the time step increase doesn't affect the path accuracy and hence the communication requirements get reduced.