Implementing an image based control algorithm for an optomechanical image derotator

In this paper an image‐based control for an optomechanical image derotator is implemented. A derotator is an optical system to support measurements on rotating components by tracking their rotational movement. As a consequence, the position and rotational velocity of the measurement object has to be known continuously. In general this would be accomplished by measuring these variables using a rotary encoder. However, not all measuring objects are equipped for this task. As a solution universally applicable to a wide range of measuring objects, an image‐based approach is developed in the scope of this work. The object is captured with a high‐speed camera to determine its position and velocity by image processing algorithms. To proof the applicability of this concept, a controller using the data acquired with the camera and a controller using data of the rotary encoder are compared. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)