- Joined
- Feb 25, 2021
- Messages
- 3,270
After getting pigeonholed for a year, I'm looking at this project again. Mostly because the homebuilding project is on hold til January. Can't promise this won't get randomly pigeonholed again, but ...
I decided hooking up poorly understood hardware to complex and poorly understood software was too big of a debugging bite. The VMC has Yaskawa servos and drivers, as well as a Yaskawa spindle. LinuxCNC has a software interface description that seems a bit more than trivial. Trying to guess how to integrate those, with a third unknown, the Mesa I/O boards seems like a oversize bite. You eat an elephant one bite at a time. Don't take too big of a bite. At about 8000 lbs, and with 2HP servos for X & Y, 3 HP for Z, and a 15HP spindle, this qualifies as an elephant.
I'd built the crane control board, which had the stepper outputs that worked fine. That seemed like a reasonable way to test each individual servo (X,Y,Z). From the documentation that I had, the servo controllers seem to take a pretty common pulse, dir and enable line. The spindle controller is essentially a VFD in that it is voltage controlled, that can come later, via a potentiometer. Problem in that the crane stepper control took 5v inputs, this beast wants 24v. Just spun a variant of the crane board with some 60V MOSFETs on 8 output pins, so anywhere from 5v to 48VDC should be useable. Got that PCB back from FAB and mostly soldered up. Surprising how fast my solder skills go to down the crapper...
I decided hooking up poorly understood hardware to complex and poorly understood software was too big of a debugging bite. The VMC has Yaskawa servos and drivers, as well as a Yaskawa spindle. LinuxCNC has a software interface description that seems a bit more than trivial. Trying to guess how to integrate those, with a third unknown, the Mesa I/O boards seems like a oversize bite. You eat an elephant one bite at a time. Don't take too big of a bite. At about 8000 lbs, and with 2HP servos for X & Y, 3 HP for Z, and a 15HP spindle, this qualifies as an elephant.
I'd built the crane control board, which had the stepper outputs that worked fine. That seemed like a reasonable way to test each individual servo (X,Y,Z). From the documentation that I had, the servo controllers seem to take a pretty common pulse, dir and enable line. The spindle controller is essentially a VFD in that it is voltage controlled, that can come later, via a potentiometer. Problem in that the crane stepper control took 5v inputs, this beast wants 24v. Just spun a variant of the crane board with some 60V MOSFETs on 8 output pins, so anywhere from 5v to 48VDC should be useable. Got that PCB back from FAB and mostly soldered up. Surprising how fast my solder skills go to down the crapper...