A mobile network for mobile sensors

When cooperative robots are used for exploring an environment, a key component of their task is to relay data back to a human operator and get input from that operator on exploration priorities. To do this a wireless communication network is required. This paper presents an approach to creating and maintaining an ad hoc communication network for relaying data to and from exploring robots. The network is made up of mobile robots acting as communication hubs. The approach relies on the concept of potential fields, but allows the potential fields to change dynamically depending on the current needs of the team. Specifically, aspects of the potential fields are turned on or off for particular robots, based on required connectivity. The resulting potential fields push the robots towards appropriate locations to maintain the network. Several policies for determining which aspects of the potential field to activate were evaluated, with policies focused on maintaining minimum connectivity performing best. In four distinct simulated environments, the dynamic potential fields approach was shown to effectively maintain a communications network and far out-perform a standard potential field approach.