Bill, As an alternative to silk screening you might look at vinyl printing. It can be printed and then a transfer sheet can be used to accurately lay it down. And there are a lot of places with the ability to cut vinyl. Tully On Tue, Nov 16, 2010 at 7:19 PM, Bill Morris wrote: > On Tue, 2010-11-16 at 18:35 -0800, Radu Bogdan Rusu wrote: > > Hi Bill, > > > > Great work! > > Ivan gets the credit for this, I just helped with the rubber cement. > > > A few suggestions: > > > > * use a larger calibration pattern that covers more of the image > > * use a calibration pattern with more squares > > The glass we are using is slightly reflective to IR but it is > manageable. However, the transparency film we are using to make the > squares is much more reflective and we had to cut out the individual > black squares. We are probably going to look at silk screening the > pattern on to a larger sheet of glass to improve alignment. > > > * if the estimates of the corners (after subpixel refinement) are still > bad, an iterative fitting process (or LMedS or > > RANSAC) could help > > We will make a bag file of our calibration tests tomorrow to help move > this forward. > > > Alternatively, a calibration plate with circles would be better. We > already have code ready that we need to commit for > > finding out centers of circles/ellipses and using those for calibration > plates a la > > > http://www.mvtec.com/halcon/applications/imgs/3d-vision-example-3d-calibration01.png, > so this might improve things. > > Can this code be made available somewhere so we can test it before > resorting to silk screening? > > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users > -- Tully Foote Systems Engineer Willow Garage, Inc. tfoote@willowgarage.com (650) 475-2827