2013/12/26 Charles Steinkuehler <[email protected]> > I'm more concerned about being able to set coordinated acceleration and > velocity limits, so I can avoid having to perform X and Y moves at 57 % > of my available max velocity and acceleration just so the occasional XYZ > move doesn't exceed 100% of machine limits. > > Details: > Given a maximum X, Y, and Z velocity of 1.0, the maximum speed of an XY > move is 1.414 (or SQRT(2)), and the maximum speed of an XYZ move is 1.73 > (or SQRT(3)), so I have to set my limits to 1/1.73 (0.577) of the actual > limits or the machine will exceed them in the "corner" case. > (pun intended) > > There's another problem: dJ1/dX can significantly exceed 1, the same for dJ1/dY and dJ1/dZ (say J1 is the first joint). And during XYZ move dJ1 = dJ1/dX + dJ1/dY + dJ1/dZ can be very large in the worst case.
I have exactly the same with my parallel robot, even worse for 6axis. The solution I can think of: calculating each joint velocity and acceleration before each move (at several points at least for a long moves) and then decreasing XYZ velocities to fit joint velocities to their limits. Andrew ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
