Patent 10275862 was granted and assigned to Align Technology on April, 2019 by the United States Patent and Trademark Office.
The present disclosure provides computing device implemented methods, computing device readable media, and systems for motion compensation in a three dimensional scan. Motion compensation can include receiving three-dimensional (3D) scans of a dentition, estimating a motion trajectory from one scan to another, and calculating a corrected scan by compensating for the motion trajectory. Estimating the motion trajectory can include one or more of: registering a scan to another scan and determining whether an amount of movement between the scans is within a registration threshold; determining an optical flow based on local motion between consecutive two-dimensional (2D) images taken during the scan, estimating and improving a motion trajectory of a point in the scan using the optical flow; and estimating an amount of motion of a 3D scanner during the scan as a rigid body transformation based on input from a position tracking device.