Interrobot Transformations in 3-D

In this paper, we provide a study of motion-induced 3-D extrinsic calibration based on robot-to-robot sensor measurements. In particular, we introduce algebraic methods to compute the relative translation and rotation between two robots using known robot motion and robot-to-robot 1) distance and bearing, 2) bearing-only, and 3) distance-only measurements. We further conduct a nonlinear observability analysis and provide sufficient conditions for the 3-D relative position and orientation (pose) to become locally weakly observable. Finally, we present a nonlinear weighted least-squares estimator to refine the algebraic pose estimate in the presence of noise. We use simulations to evaluate the performance of our methods in terms of accuracy and robustness.