A relative pose and target model estimation framework using calibrated multicamera clusters is presented. It is able to accurately track up-to-date relative motion, including scale, between the camera cluster and the (free-moving) completely unknown target object or environment using only image measurements from a set of perspective cameras. The cameras within the cluster may be arranged in any configuration, even such that there is no spatial overlap in their fields-of-view. An analysis of the set of degenerate motions for a cluster composed of three cameras is performed. It is shown that including the third camera eliminates many of the previously known ambiguities for two-camera clusters. The estimator performance and the degeneracy analysis conclusions are confirmed in experiment with ground truth data collected from an optical motion capture system for the proposed three-camera cluster against other camera configurations suggested in the literature. 
Scale recovery in multicamera cluster SLAM with non-overlapping fields of view