has anyone interfaced linuxcnc with an abb NextStep?

Got a used abb/Baldor nextstep on its way would like to control it with linuxcnc, have 3 matching Microflex drives to go with it.
would like to use the ethernet ports, but it has Serial and digital IO also.

Nope, your analysis is pretty fair. ABB's NextStep(or SmartMove, EuroServo, SmartStep/3, NextMove, etc etc) is a motion controller (platform-- as it integrates both the software functionality of Linux CNC on a PC (I think AB's software is called "Workbench" or something stupidly generic like that) + an industrial quality standalone unit, which end up communicating via RS232 or RJ45 to your PC. The standalone then ends up as a 'master' controller to the actual motor drivers (i.e. those MicroFlexes).The stand alone unit is pretty well designed, as one would expect, but you end up tying yourself to so many proprietary junk, that it's really not worth it unless you're building your entire career around Allen-Bradley/Baldor millwrighting.


That being said, those MicroFlex'es ain't too shabby. They're pretty old, but it's got points because it was one of the first brushless drivers in it's class and it was pretty flexible. Like, if you used the compatible Baldor motors, the drive would give you real time power analysis statistics so you can calculate the power factor, current draw for each leg, etc. Each drive basically gave you more or less all the tools needed to remotely run a full diagnostics suite to see what's generating your fault....

This is a long winded way of saying, I'd bypass the NextStep and use the Microflex(s) presuming with it I had the appropriate Baldor motors that were paired with the original setup, and those motors were spec'd to whatever requirements I had. The value proposition is in the ability to pair the drive with the motors. If not, ehhhhh... well, just look at the Ti InstaSPIN and you'll see how easy it is to design a drive to your liking with absolutely amazing performance for a weekend's worth of reading PDFs.

I think you can disconnect all from NextStep and add your pc + mesacard + Microflex Drive using X3 and X7 connector only for exe (drive with analogue signal & digital i/o + encoder simulation output as Lcnc feedback). So you can run your Machine with Lcnc and Microflex Drive ..... NextStep go to garage for a long sleeping. I did not remember this link I kept from a bit on firefox ... but maybe it is also possible to use pyprofibus ... pyprofibus for Linuxcnc ... never try.

regards
giorgio

So my nextMove e100(not a nextstep) came in, and yes seems to be a stand alone controller. the complexity is advanced, think this is how it would work. I would like for linuxcnc to run the kinematics and interface, not going to write it from scatch in ABB Mint language. would like to use mint for basic I/O and Tuning, the encoder are build to the Microflex drive then Feed into the NextMove. if i could feed them back to linuxcnc that would be cool, USB serial maybe. the NextMove has a heap of analog in and out along with some high speed Digital I/O, let it take all the Estop, limit, home, Analog I/O... I have never did a servo setup in linuxcnc do i have to have a Special card or would duel Parports work?

Anyway this is a concept machine, if anyone wants to help i will posting info here. the hardware fell in my lap so going to play with it

J

Bypass the NextMove - sell it on ebay (old PLC junk like that can often be worth close to MSRP if a company needs to replace that specific component).

Use the money to get the Mesa 5i20 or whatever as K1 said . You'll have at least a few hundred bucks left on that.

(Or if you're adventurous, this is a way better/more flexible deal, should you happen to know VHDL or Verilog. Alternatively, you could download the Xilinix 20 gig package, rip the 5i20 synthesized code, re-configure for your wire in-out for proper pinning, and then load it onto your Zynq -- www.digikey.com/product-detail/en/digile...1286-1044-ND/4840864 --- no seriously, haha don't do this unless you at least have played with FPGA's in undergrad, just get the 5i20 -- hey just throwing out options depending on what you really want to accomplish, since you didn't really define your full equipment, budget, timeline, or goals, I'm trying to hit a bit of all the bases...)

I think you're missing the point of the Microflex drive paired with a compatible Baldor motor. They're designed to offer closed-loop feedback real time (via syncro serial, or incremental encoding or whatever). That means you're really not going to be hard-up for latency since all of the high-resolution negotiation is done on the MF-drive itself with the motor. You bang out an instruction a millisecond or whatever to the MFdrive. The MFdrive then is taking care of all the microsecond resolution positioning/closed-loop velocity adjustments by directly talking to the motor. (See: MN1919.pdf re: X7 and X8).



An oversimplified version of what's happening here is HostPC (running Linux w[/img]/ your MESA board) is firing off a g-code instruction (see arrow "1").

Then there's a lot of rapid chat between the 2 and 3, with the MF drive saying 'alright go here, at this velocity' (arrow 2), and the motor is firing back (arrow 3) some info saying 'alright I'm at point x,y right now'. The drive gets that message, and goes "uh-oh, you should be a little further..you must be loaded pretty hard, let's see how you do with half an amp more". The important thing to note is that there's no computer interaction here to be the bottleneck[1]. The logic in the MFdrive + the parameters you set it to operate within continuously adjust the working parameters so you get a closed-loop process control.

[1] Serial and parallel port are actually super fast. You're just banging out bits. The information limit is pretty much how fast your square-waves can rise/fall while maintaining enough signal fidelity to keep the transmission 'eye'. Unlike USB there's no overhead for host-device negotiation and all sorts of things like that. You can get USB3 down to around 125 usec pretty reliably which is good enough for machining, no doubt, but don't under estimate

so digging in to the they have step and dir so dive just like a stepper drive. also can set up a if out of position by number of steps then send signal on general output. there is a encoder feed though for getting drive position to the nextMove or putting them in follow mode( ie 1 axis with 2 or more motors). the nextmove has four stepper motors out, think this would be good for tool changers / parts loaders whatever. anyway love all the idea maybe make some videos.
j