I’m starting this thread to document the Holey Triangular Calibration development process.
This process is different than the current process as it determines the exact (as exact as possible) coordinates of each “cut” location. The current process only considers the distance between two cuts at the top, two cuts at the bottom, and between the top of the work area and a cut near the top. It is based upon the assumption that the cuts are perfectly centered. The holey process measures the distances between five holes (one of which is at 0,0) as well as a mark that is directly below the center hole. Using these measurements, its possible to determine the exact coordinates of each of the holes. With these coordinates, there is no need to assume that the cuts are perfectly centered is eliminated and facilitates the use of chain stretch compensation. The hope for the holey process is to improve calibration results.
The gcode to create the holey pattern for a 4x8 sheet of plywood is here (untested as of 8/29/18):
The python code to perform the optimization is here (untested as of 8/29/18):
Right now, you have to manually enter the distances into the code as defined by this terribly exaggerated diagram: