Enhance PIV results near rigid boundaries with Rigid Object Tracking and Stabilization
The presence of moving objects in PIV raw images is more a reality than exception for PIV flow investigations today. The PIV investigations focusing on flows close to the boundary require accurate masking of the moving objects, and dynamic masking techniques are quite useful in digitally removing these objects from PIV raw images.
The new Dynamic Masking add-on introduced in DynamicStudio 6.4 can be used to remove rigid objects from PIV images. This is achieved by first tracking the rigid objects in the field of view (FoV), and then stabilizing them by making a coordinate transformation from a camera-fixed coordinate system to an object-fixed coordinate system. The new masking strategy is a combination of Rigid Object Tracking (ROT), Rigid Object Stabilization (ROS) and static masking.
The Dynamic Masking tool has been applied to a vibrating airplane model in a wind tunnel (see below). The model is vibrating due to aerodynamic forces (left) and is stabilized using ROT and ROS (right). First, a sub-image that contains the rigid object is selected, secondly this image is tracked within the FoV and the sub-pixel shifts are determined (ROT). Thirdly the shifts are corrected for to stabilize the object (ROS) and finally, a static mask is applied to the ROT and ROS stabilized image.