Dispersion and Dispatch Movement Design for a Multi-Robot Searching Team Using Communication Density

Abstract

In recent years, since the cooperation of multiple robots provides numerous advantages in engineering applications, the research topics on multi-robot systems have received great attention. Due to the complexity and/or difficulty of a task, the performance by one single robot is usually limited. However, the performance limitation could be overcome by the cooperation of multiple robots. Compared with one single robot, a multi-robot team could provide advantages such as better efficiency, robustness, execution time saving, and so on, which are mainly achieved because of the characteristics of multi-robot cooperation. In a multi-robot team, the possible abilities of each robot can be usually classified as the following four types: communication, sensing, computation, and actuation. Among these abilities, the communication between robots is the most important factor for the cooperative characteristics of a multi-robot team. If every robot is considered as a networking node, the communication links between any pair of robots form a communication network. In order to guarantee the cooperative characteristics of a multi-robot team, the method of maintaining a good communication network thus becomes a critical issue. Considering the robot mobility, environmental limitation, user requests or other factors, many moving algorithms driving robots to form a good communication network are previously proposed. In most of these algorithms, robots are assumed to be well equipped with advanced sensing or positioning devices such as global positioning system, radar and/or camera. These equipments could provide enough information for the moving algorithms and hence output good performance. Sometimes, because of the computation complexity of the algorithm, other advanced processing units are also needed. These assumptions, however, are not easily implemented in real applications. Moreover, cost or retrieve would be another important design issue for the searching task by a robot team. To achieve the cooperative characteristics and information sharing, the team of robots must maintain a good communication connection while moving or performing tasks. In real implementation, sharing enough information quantity among multiple robots could be a challenging problem. In this chapter, inspired by the bacteria mobility behavior, a dispersion movement design for a multi-robot team is presented. The goal of the dispersion algorithm is to maintain the communication network among robots and enlarge the coverage area as widely as possible. Unlike other previously proposed algorithms, the O pe n A cc es s D at ab as e w w w .in te hw eb .c om