Charles Steinkuehler wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > I am getting close to being able to put together one of the "delta" > style 3D printers, and I will need to put more thought into homing. > > The current state-of-the-art for this in the Arduino world is shown in > the following videos: > > http://www.youtube.com/watch?v=1eNz1l56H5E > > http://www.youtube.com/watch?v=rTuql1iJMAQ > > The process is as follows: > > * Each joint is homed to a switch at the top of the travel range (you > can barely see the belts moving for this at the beginning of the > video) which provides approximate homing > > > > Question: > How do I begin to hook in a homing procedure like this to LinuxCNC? > It seems like each vertical slide could have an optical sensor that detects a known position of that slide. Then, you home each one in joint mode, and set a home offset from that position. By making measurements, you should be able to calculate the right offset from the sensor to make the rest of the geometry work. The min and max travel limits can then be set from the home position.
The ini file parameters for homing are mostly self explanatory. You have a home search velocity, then a lower velocity for a more precise approach to the switch. Sign of these values controls which direction the slide moves toward home. Any digital input can be used to sense the home switches. See any of the common configs file sets to see how these are hooked up. There is a homing sequence to home one at a time, but with separate switches, it might actually be better to home them all in parallel, keeping the machine more centered during the home. (Note in the first video, he actually bends one of the vertical rails.) Or, am I misinterpreting what you are asking? Jon ------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
