1. A method for identifying information about a cluster of objects in motion, the method comprising: identifying a path for a center of mass for the cluster of objects using a sequence of frames of sensor data generated by a sensor system in which the path is identified with respect to a coordinate system for the sensor data, the path for the center of mass comprising an estimation of a path along which the center of mass moves from image to image in the sequence of frames; identifying a relative path for each object in the cluster of objects with respect to the coordinate system for the sensor data using a minimization algorithm and constraints for the minimization algorithm, wherein the relative path is relative to the path for the center of mass for the cluster of objects; and identifying a final path for the each object in the cluster of objects with respect to the coordinate system for the sensor data using the path for the center of mass for the cluster of objects and the relative path for the each object in the cluster of objects, the final path comprising a sum of the path for the center of mass for the cluster of objects and the relative path for each object in the cluster of objects.