Active, lifelong sensor synchronization: A Kalman filtering approach

In robotics and in many other fields, time synchronization between a host computer and sensors or other computers is essential for many reasons. Whereas past approaches have focused on phase and frequency estimation, little discussion seems to be available in literature on adopting uncertainty on these estimates to determine whether synchronization is out of bounds and to actively decide when to synchronize again to reduce uncertainty. This paper presents an algorithm to perform such active synchronization based on a Kalman filtering approach. The performance of the algorithm is illustrated by synchronizing a Hokuyo URG laserscanner with a computer.