TRIGGER FOR BLADE IMAGING BASED ON A CONTROLLER

摘要

A rotating rotor in a turbine has blades attached. At least one blade is a reference blade of which a reference position is determined by a Once-Per-Rotation sensor. A camera positioned at a viewing port takes a sequence of images of all the blades during a rotation at a trigger moment determined by a controller. The controller receives a signal indicating that the reference blade passes its reference point. The controller is provided with data about the number of blades, the position of the camera and a desired dwell of an image related to the blade. The controller calculates the trigger moments and generates trigger signals to the camera. The trigger moment is adjusted for changing rotor speed by extracting a blade feature from blade images. The camera records images that are labeled and stored as image data on a storage device.