Biblio

Untethered microrobots actuated by external magnetic fields have drawn extensive attention recently, due to their potential advantages in real-time tracking and targeted delivery in vivo. To control a swarm of microrobots with external fields, however, is still one of the major challenges in this field. In this work, we present new methods to generate ribbon-like and vortex-like microrobotic swarms using oscillating and rotating magnetic fields, respectively. Paramagnetic nanoparticles with a diameter of 400 nm serve as the agents. These two types of swarms exhibits out-of-equilibrium structure, in which the nanoparticles perform synchronised motions. By tuning the magnetic fields, the swarming patterns can be reversibly transformed. Moreover, by increasing the pitch angle of the applied fields, the swarms are capable of performing navigated locomotion with a controlled velocity. This work sheds light on a better understanding for microrobotic swarm behaviours and paves the way for potential biomedical applications.

Applications such as fleet management and logistics, emergency response, public security and surveillance or mobile workforce management use geo-positioning and mobile networks as means of enabling real-time monitoring, communication and collaboration among a possibly large set of mobile nodes. The majority of those systems require real-time tracking of mobile nodes (e.g. vehicles, people or mobile robots), reliable communication to/from the nodes, as well as group communication among the mobile nodes. In this paper we describe a distributed middleware with focus on management of context-defined groups of mobile nodes, and group communication with large sets of nodes. We also present a prototype Fleet Tracking and Management system based on our middleware, give an example of how context-specific group communication can enhance the node's mutual awareness, and show initial performance results that indicate small overhead and latency of the group communication and management.