Max acceleration/deceleration AllInOneDC

[AMDlloydsp]

We had a discussion yesterday in the shop for which I could find no answers in the manuals.

How fast, in i/s/s can the AIODC accelerate and decelerate (properly, on healthy hardware)?

Off-hand, I don't remember which servos we bought, but it was for an R2E4 conversion, they are your servos and power supply, and we left all the acceleration parameters alone.

Thanks,
Lloyd

[diycncscott]

Lloyd,

Accel is determined entirely on the motor, mechanical load and inertial characteristics of the machine and is not limited by the ALLIN1DC.

For a knee mill such as the yours, you should probably set the accels to ~.300 -Though autotune would probably calculate that the motor CAN accel as fast as .05 or so, I think you'll find it's too abrupt for the machine itself as the machine/mechanicals just aren't rigid enough to handle it.

[AMDlloydsp]

Ok, that answers a 'config' question.

We let the control auto-tune itself, and we have seen no problems with overshoots or any adverse noises. One of the guys brought the question up during lunch, and I couldn't answer. It's obviously not critical to our use of the machine, but it would be nice to understand how it works, and what the values mean.

In the docs, I can only find how the set the values. How do the configuration numbers correspond to inches/sec/sec acceleration or deceleration rates?
I may presume too much, but it feels to me like a value plugged in there should equate to a specific rate-of-change. Yes? No?


Thanks,

LLoyd

[diycncscott]

Lloyd,

Our acceleration parameter is not expressed as a rate of acceleration. It is simplified to represent the time it takes for a motor/axis to reach it's maximum velocity. For example, if accel is set to .5, the control will accelerate that axis to max rate in 500 milliseconds.

[AMDlloydsp]

Thanks, Scott. That explains how it works, and what the ramp will look like. I can do the arithmetic myself <G>.

Lloyd