Eric H. Johnson wrote: > Hi all, > > What is the maturity of the Hexapod configuration under EMC2? I have never > done anything with hexapods, but I was asked about the feasibility of using > EMC2 for implementing a control system for a hexapod. I have not seen the > actual unit, but what I have been told is that it is from a university lab, > is basically electrically and mechanically sound, but that they have never > managed to get the control system working.
I'm sure it would not be a turnkey install.... but clever enough people could certainly get it working. Things like homing will be the "fun" parts. Basic hexapod kinematics are in there, and were used back in the NIST days. They'd need some porting effort to interface with the newer motion controller, but the tough math parts should be fine. > Is the Hexapod configuration and kinematics (genhexkins) fairly universal, > or would there still be quite a bit to do to adapt to a specific > configuration / orientation? The readme in the hexapod sim configuration > references a "Minitetra" type. What is a minitetra type, and what other > types are there? The only orientation I am familiar with has three pairs of > axes centered 120 degrees from each-other. I was not aware of any other > orientations. I think the different types have to do with whether the strut lengths vary, or the strut lengths are fixed and their attachment points move. (I think one of Till Franitza's hexapods used 6 parallel vertical slides, with one end of each strut attached to each slide, and the other end attached to the "flying" platform that held the spindle. I did a quick google but can't find the info - he used to be at the Univ. of Stuttgart, but appears to have moved on from there. > Also, from the standpoint of drivers, I believe the six motors are servo > motors. Can I use two Mesa m5i20 controllers with the servo FPGA > configuration for controlling the six axes? Is there any limitation in the > mesa driver which would not permit the use of two boards simultaneously? I'm not entirely sure about the current driver, but I think it will handle multiple cards. The new driver that I'm (slowly) working on will definitely handle more than one card. It will also allow for a wider variety of "stuff". I'm sure a 6 axis servo configuration could be done with a single board and two 7i33 breakouts. Depends on your time frame though, I got sidetracked into a bunch of emc2.1 stuff, and am only now getting back to the 5i20. (I have some docs to write up tonight, then I hope to resume 5i20 work this evening.) Regards, John Kasunich ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
