Topics created by 3DPMicro

@T3P3Tony thanks. I have a converter on the way

@3DPMicro Pwm to analog converter 10V

@sindarius thank you

@pjl What are you suggesting as a different control approach over PID? I agree it may not be ideal but improving inexpensive hardware (that I already have) that otherwise performs exceptonally well seems worth considering and PID, as far as I can tell is still standard for closed loop servos.
There are probably only 2 or maybe 3 desired schemes so not too bad. Getting past the software control part is only 1 element though. I would still have to sort out the hardware control of at least 3 trim pots (digipots?). At this point its simply an exploration of possibilities.

its a good thing I just bought my wife a new car because the first thing she's going to ask is why I need another Duet

@phaedrux I was looking for a way to kill the motor instantly but I think I worked past it with rubber stops. I was testing a PMDC servo on my motor test rig with 7kg's of mass simulant tungsten attached. At 42kmm/m travel speed concern was a loss of control could get ugly. All went well though. Thanks for the support

@dc42 edited to reflect that

@luke-slaboratory there is some discussion of it here https://forum.duet3d.com/topic/14441/higher-input-voltages-for-steppers

@o_lampe said in Hypothetical question regarding acceleration and latency:

@dc42
That's clever! So we don't have issues with linear acceleration, but external drivers with 'S' curved accel would be a problem?
At least when they are mixed with linear acceleration drivers

External drivers that have a latency between receiving step pulses and moving to the requested position could cause mismatches in the XY tracking. If both X and U used those drivers and they had equal and constant latency then X and Y would track properly.

@dc42 thank you Sir. Its alive and well

I sit corrected .... the feature I am talking about is in Cura and not in Duet. Furthermore, it is in an add-on to Cura.
Specifically it is an add-on for printer settings (and I installed it years ago so don't ask me how to do it). It has settings for 'heat up speed' and 'cool down speed' in degrees C per second. Given that information, for dual (or multi) extruder machines, the slicer can determine at what time to call for heat-up of the currently unused tool so that it is at or close to operating temperature when the new tool is called for. Also, it allows the current extruder to start cooling down to standby temperature before it is finished.
I am pretty sure that the calculations involve temperature minimum settings in the slicer as to what temperature is hot enough to start printing or so that it doesn't cool down below minimum temperature before stopping to print with the tool.
The setting up of this was kinda hit and miss when I tried it but it definitely reduced wait times during tool changes.

Sorry to not clarify this before.

Edit .... I am assuming that extruder temperatures and standby temperatures of all extruders have been set. The slicer will call for the standby nozzle to heat up before the nozzle is actually used. The 'when' is based on your heat-up speed and the setting of what the minimum temperature should be before starting to print.
The same thing happens on cool-down of the currently in-use tool. The cool-down happens before the current nozzle has stopped printing. Cool down is not that important because it happens quickly but heating up the new nozzle in advance can be a big time saver.

Thanks guys. I found it. Just had to actually look

I would be interested to see him test the 2660. They run well past the 500 rpm or so he's getting with the 2208's or maybe the arduino is just running out of snot. I was getting over 1800 rpm, accelerating 1.5 kg of tungsten ballast (w/ diagonal moves) on my test rig at high acceleration and 18k mm/m with Duet Ethernet set to 16x interpolated.
https://youtu.be/g2fO7k3WzwU

Thanks. I may implement the dual switches . Looks like there are solutions except for if 1 motor moves and the other doesn't say if it was at the bottom of travel going towards home. I think I have an idea that can take care of that mechanically/electrically. If it gets too far out of wack it will open/close a circuit that kills power or activates an emergency stop

Thank you Sir

Great. Thank you.

@3DPMicro
I would tackle the Haas with Linux CNC and Mesa board. The forum is very helpful. Everything I've done with it was stepper based, but lots of guys did servos.

This forum is also helpful, but I put these boards in machines that are more appropriate for it. To be honest, Linux CNC was far simpler to configure on non-printer applications... It's so printer oriented that you have to jump through hoops to do cnc things. But, sometimes a tiny board is more appropriate (portable machine), and worth the learning curve to configure.

@arhi Yes it's "normally closed", the same as all my other end stop switches. So bad contacts or wires falling off mean that it "fails safe" (triggered).