Scalable control system for bluetooth mobile devices

Bluetooth (BT) devices are usually grouped in a star topology in small clusters called personal area networks (PANs). The population of BT PANs is limited to 8 devices, but setups in entertainment theme parks or interactive installations might want to employ a larger number of mobile devices. In those scenarios, only off-theshelf devices, without any hardware modifications, can be accepted, so a PAN must be extended to become a low-cost cellular network for consumer products. We explore the design of such a cellular network of BT nodes. The paper discusses the practical aspects of a wireless control system and reports the experience obtained from implementing a proof-of-concept system. The prototype implementation is based on BT dongles, which act as cellular base stations, and Sphero robotic balls, which are low-cost consumer mobile robots. This wireless control system allows the robots to be controlled by a single device; it is modular and scalable and offers handover and localization services typical of common cellular networks.