Observability analysis for mobile robot localization

In this paper, the problem of localize two mobile robots is considered. The robots are equipped with proprioceptive sensors (like encoders) and exteroceptive sensors able to provide relative observations between them. In these observations, one robot detects and identifies the other one and measures some relative quantity. An observability analysis is performed by taking into account the system nonlinearities and for four different relative observations. The theoretical results are validated by simulations and experiments carried out on real platforms. In these experiments, an extended Kalman filter is adopted to fuse the information coming from the encoders and the sensors performing the observations.