It's a SCARA. They are very common for pic-and-place machines but one of our guys a few years ago wrote a thesis while building one and testing it for stiffness. I believe the guys was from India. The current SCARA kinematic files are based on his work. Shouldn't be much of a problem to control the electrics with EMC.
Rayh On Wed, 2007-12-05 at 02:50 +0200, Roland Jollivet wrote: > Hi > > I believe that the greatest hurdle in constructing a small CNC machine > is the cost of the linear slides, and I've been trying to think of a > way to alleviate this, and come up with a 'Pivot Mill'. While this is > robotic in configuration, it is for all intensive purposes intended to > supplant a conventional 3 axis machine. (X,Y,Z) Bearings are > relatively cheap, and construction of the mechanics fairly simple. > > I have drawn and uploaded a concept picture here, of what I have in > mind. > http://www.fotothing.com/CAONgallery/photo/9e62959f5230b6745b40b5285739b62c/ > > There are still three axis, but they are mathematical functions of > each other, essentially transparent to the user, and where Z is the > most complex interaction. Also notice that the tool will stay vertical > during motion due to the dual strut. The servo's are not shown, and > would typically introduce a further non-linear relationship since they > would act indirectly, or at an angle . > > To control something like this, from what I've read here, sounds like > a task for EMC. So, how difficult would it be to implement this > inter-relation between the axis? > > As far as the user is concerned, the machine must still execute linear > moves with normal G-code, as in G1 X200. > So the machine has ROTARY AXIS, but executes LINEAR MOTION. > A JOG in the Z axis will cause all three joints to move, but the tool > will only move vertically > > Of course, there are always rigidity issues, but it's easy to beef up > a pivot arm, and this is only intended to be of the calibre of > 'dremel' type, benchtop, CNC machines. > There are other appealing factors like the inherent extended reach, > for tool changing, and if the machine were placed centrally on a > table, it could serve four work areas, as quadrants. (assuming here a > 360deg. central column) > > So, is this worth pursuing? Is the functionality required already a > sub-set of EMC, or is it a huge re-work? > > Regards > Roland Jollivet > > > ------------------------------------------------------------------------- > 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
