There are programs designed to correct for this for projections, although I have not researched them in the past few years and I am sure they have gotten better.
One application that probably fits your needs is correction for theatrical gobos. Gobos are used to project images from theatrical fixtures, but if the fixture is not square to the projection surface it will appear distorted. Since it is frequently not possible to position the fixture squarely, the alternative is to correct the original artwork so that when projected from the actual location it appears correct. You could use this same approach- adjust the art, then feed it into EMC. Try googling gobo correction or other combinations with the word projection, or see what might be on Source Forge. I realize that is not an answer for the issue in EMC, but it will solve the problem for this application. Perhaps there are open algorithms out there that can be applied to EMC as well. Javid ----- Original Message ----- From: "Ray Henry" <[EMAIL PROTECTED]> To: "Enhanced Machine Controller (EMC)" <[email protected]> Sent: Saturday, December 01, 2007 10:18 AM Subject: Re: [Emc-users] open loop galvanometer control > > Hi Klemen > > The distortion of the shape of the image on the wall is often referred > to as parallax by the folks that work with projectors and cameras and > images. > > In EMC2 and machine tool terms we would think of it as a non-trivial > kinematic and you are into the very recent post by Jeff. The X, Y, and > Z axes of your "machine" are not square to each other. In fact there is > interaction between them depending upon where the spot (tool) is and the > angle of the tool to the projection plane. > > If the laser were moving about in X and Y so that it's projection angle > was fixed you would remove one of the two sources of parallax. The > other source of parallax is the angle between the XY plane of the laser > motion and the XY plane of the screen or wall that the laser light is > hitting. > > Fascinating problem to think about but I have no instant, easy solution > that can be plugged into HAL. > > Rayh > > > On Sat, 2007-12-01 at 06:13 -0800, Klemen Dovrtel wrote: >> My second problem is, that I think the position signal >> from emc should be modified a bit ( >> hight_on_the_wall=constant*tangens(emc_output signal >> ), because otherwise the "drawing" on the wall will be >> stretched at the sides. How can i achieve this? > > > ------------------------------------------------------------------------- > SF.Net email is sponsored by: The Future of Linux Business White Paper > from Novell. From the desktop to the data center, Linux is going > mainstream. Let it simplify your IT future. > http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4 > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------- SF.Net email is sponsored by: The Future of Linux Business White Paper from Novell. From the desktop to the data center, Linux is going mainstream. Let it simplify your IT future. http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
