Uses opencv to find checkboards and compute their 6D poses with respect to the image. Requires the image to be calibrated. Parameters: display - show the checkerboard detection rect%d_size_x - size of checker in x direction rect%d_size_y - size of checker in y direction grid%d_size_x - number of checkers in x direction grid%d_size_y - number of checkers in y direction There can be more than one grid%d declared, the numbers should grow consecutively starting at 0.