AXCAM

[Mike Nash]

I have been looking at AXCAM to see if it can do Traverse Winding. I've mentioned before trying to do this with the CTRIO2 and having little stutters from trying to make dynamic changes.

I don't see a video on it yet. The instruction help is pretty involved. I can't even have it in the simulator, much less run it. I don't have a BRX to try it on at this point. And I have near zero experience with electronic camming.

Basically, if I have two linear travel endpoint positions, a displacement distance to travel per one cycle of the master encoder on the spindle (which I can read as quadrature input to two input points?) can I calculate the desired linear position, populate a table and load it for the AXCAM instruction to use? There would be a dwell at each end of linear travel calculated into the table.

Of course it needs to repeat the cycle until the spool is full.

Second question, will there be similar functionality at some point for the CTRIO2 (or CTRIO3 or whatever) in the future?

[BobO]

Is the ratio between the two linear moves constant or changing? If it is changing, then I would say yeah, AXCAM should do the job, but would definitely need a short dwell at the end to set up the next cycle. If the ratio is constant and you just need to make small corrections on the fly, I'd look at AXFOLLOW. If this is a straight Y = X * variable ratio, AXGEAR might work, just compute the desired ratio for each cycle.

When following an encoder, high resolution is your friend. There is a filter that you can use to smooth out the velocity calc, but the slaving is only as good as the master's velocity. At the extremes, fast filter == rough slave and slow filter == laggy slave, so more resolution makes it easier to find the smooth enough/responsive enough compromise.

We are planning to do an AXIS module for BRX, which adds more axes as expansion I/O (and replaces CTRIO2 on BRX), but we do not envision building such for DL205.

[Mike Nash]

Is the ratio between the two linear moves constant or changing? If it is changing, then I would say yeah, AXCAM should do the job, but would definitely need a short dwell at the end to set up the next cycle. If the ratio is constant and you just need to make small corrections on the fly, I'd look at AXFOLLOW. If this is a straight Y = X * variable ratio, AXGEAR might work, just compute the desired ratio for each cycle.

In general, the ratios are all fixed once started. There should be a zero move dwell for 0-2 spindle revs worth of master pulses, a linear following ratio for x.x revs (depending on travel needed per rev) then another zero travel for 0-2 revs. Now head back to the start position taking x.x revs to get there and repeat. Nothing should change until the product is changed. The follower can't overshoot at the dwell points though and this might be an issue with the curve fitting action.* So ideally this should be a trapezoidal profile for a constant pulse rate from the master encoder _/¯\_ . In reality, the master is constantly slowing after each 1/2 cycle since the diameter is building layer by layer.

Is it possible to chain move profiles and if so, without losing track of master pulses?

We are planning to do an AXIS module for BRX, which adds more axes as expansion I/O (and replaces CTRIO2 on BRX), but we do not envision building such for DL205.

This is good, but it sounds like it must all be local? Or is this going to also be available as Ethernet remotes?

* I have been playing in offline and the equal spacing of master points seems to require a lot of data pairs to try to force the line from one slope to another without excessive curve smoothing. Funny how something that is great for one thing is problematic for another.

[BobO]

All of the coordinated moves are position based, and the master is unaffected by slave moves. So yes, moves can be sequenced.

The AXIS module will be a full coprocessor, so they will be capable of operating in remote bases. We might have to adjust the feature set when remote.