Tracking Rectangles with Perspective Distortion

[wre136]

Hi,

I'm extremely new to vision tacking. I'm taking several pictures of an Ultimate Ascent rectangle goal (It matches the 2 point goal but is 60% the size due to lack of material) from different angles.

I'm trying to use the Vision Assistant and its shape matching function to find the shapes but it will only work if I am look straight at it and not at an angle.

I can use edge detection to detect the left, right, top and bottom edges of the rectangle and use the caliper function to find lines of intersection, angles and lengths which is very effective for giving me the info to determine distance and what not. However, then I run into the issue with having more than 1 rectangle on the screen and now edge detection no longer works.

I am trying to look into the "Vision Targets White Paper" (See attached document) and its section where it talks about Perspective Distortion (page 11). It shows where due to it, we cannot find shapes. But then by using "some work", we can detect shapes with the quadrilaterals. I'm looking for help on what this work is.

I've tried looking into Contour Analysis to try and get something I can use to match what the doc is doing but I am not making any ground on it.

I'm looking for any help on how to deal with this distortion issue or Vision Tracking in general with Vision Assistant. Thanks!