Cooperative Geolocation and Sensor Bias Estimation for UAVs with Articulating Cameras
Mark Campbell, William W. Whitacre · 2009
The cooperative geolocation of a point of interest (POI) using multiple UAVs with articulating camera sensors is considered. In the practical application, nonzero mean errors (biases) in the estimate of the UAV state are a significant source of geolocation error. The proposed approach is to use the onboard navigation solution in the estimator and further to consider biases across all UAVs, and jointly estimate both the biases and the unknown POI location. Furthermore, a decentralized solution is proposed which uses marginalization of the biases, thus allowing the UAVs to share only information about the POI and model only their local biases. This approach saves significant computation and scales well with the number of UAVs. Both real flight test data and hardware in the loop simulations are used to demonstrate the improvement in geolocation from bias estimation, as well as the effectiveness of the new decentralized POI and bias estimation approach, for stationary and moving POIs.