Remember Arc Lost position

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Remember Arc Lost position

Postby shad » Mon Oct 17, 2016 7:29 pm

Hello Balazs!
Is it possible to remember arc lost XY position inside controller hardware and then transmit it to the UCCNC registers?
It's working now for any THC - by controlling ArcOK input LED or pin in the plugin, but we have minimum 40 msec delay. On the 10000 m/min cutting speed it's will be 6.6 mm error. :cry:
It's will be great to make it instant in the controller and store in the UCCNC. What you think?
-- Andrew
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Re: Remember Arc Lost position

Postby Vmax549 » Tue Oct 18, 2016 9:35 pm

Auto restart to an "exact" position it not realistic as there are FAR too many variables involved. I have tested auto restart routines that get VERY close to perfect using UCCNC as is (;-).

(;-) TP
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Re: Remember Arc Lost position

Postby shad » Wed Oct 19, 2016 5:05 am

Terry, this is very realistic task. Now I have 10 msec loop time for communication with controller and UCCNC Neuron Plugin has information about arc lost position very close to the real arc lost position. It's work perfect now. But for me this is not auto restart. Operator have to understand what happens and solve problem. Only after this will start Cut recovery procedure.
This is the screen with opened Cut Recovery dialog. Operator just select recovery mode and continue to cut.

My question was for other THC controllers, because they receive ArcOK signal only from teh (as you like to say) software with 40-60 msec delay. This is very big value, especially for hi speed cutting.
I think UC has motion planner inside controller hardware and this is not problem to catch current position when ArcOK signal will lost.
IMHO it's will be very helpful for plasma cutting.
Also Interesting what to say about it Balazs :)
Attachments
NeuronCutRecoveryDialog.jpg
Neuron Cut recovery dialog
-- Andrew
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UC300ETH-5LPT
NEURON Lite THC
http://neuroncnc.com/
shad
 
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Re: Remember Arc Lost position

Postby Robertspark » Wed Oct 19, 2016 1:00 pm

How did you get 100hz loop?

Could lost arc not be done like g31.... ie monitor arc Ok signal and when lost trigger 6 axis dro dump to #vars.... that way vars can be called if you want to instigate lost arc position..... I would like the active gcode line too.... that way it makes restart very easy for me

Sounds like a useful feature... (anyone else seen such a feature before, how do the big boys do it (hyperthem etc))
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2106, Neuron Lite
UCCNC v1.2105 Macro Manual
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Re: Remember Arc Lost position

Postby Vmax549 » Wed Oct 19, 2016 2:48 pm

Hi Robert you can build a simple version of auto restart as a macro Loop . You would monitor teh arc ok and IF it goes inactive you record the XY positions AND teh current line #. Then to restart you go back to teh beginning of teh line # and restart motion then when the torch is about to cross teh Fire point you fire the torch.

THEN there is auto refire where when the arc goes out and the torch stops it will attempt to refire 3 times . IF it can refire then the macine will continue motion if after three failed attempts teh machine will STOP.

I was able to get Restart down to a tolerance of teh size of the cut kerf width. Always use teh + tolerance so that it does not leave a spot uncut.

I had this in Mach3 as well . worked fine for 99% of cutting.

Teh active line feature would be nice (;-) Although when you stop in UCCNC it does shown teh active LINE # you are on so it is easy to restart or run from here.

Also Run from here works EXTREMELY well in UCCNC compared to Mach3. Manual restarts with plasma are a piece of cake.

(;-) TP
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Re: Remember Arc Lost position

Postby Robertspark » Wed Oct 19, 2016 2:55 pm

Thanks TP, like most things with me, brain kicks in after mouth has opened... (typed) ;)

At 600ipm, 60ipsec, 100hz plugin loop, 0.1" event trigger to save dros to vars....

My cutting is around 200ipm.... hence error is negligible if the first loop I'd missed or part loop to get the dros and line number
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2106, Neuron Lite
UCCNC v1.2105 Macro Manual
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Re: Remember Arc Lost position

Postby Vmax549 » Wed Oct 19, 2016 4:40 pm

HI Robert, Shad was able to do a 100hz loop by programming it into his plugin. But to auto restart you basically are doing a FLYING restart back to teh fire point. The torch starts moving following the path and you have to GUAGE were to prefire in order for it to be cutting when it hits teh restart point.

There ARE other things you have to be aware of in the process such as you have to disable teh arkOK signal to allow teh torch to MOVE without an arcOK signal then turn it all back on AFTER you are cutting.

Things like latency, feedrate, on to arc delay time for teh torch all work as variables to the process.

SO FAR it works as well as a manual restart. I allways try to work inside the framework of UCCNC so that anything I can make work can be used by everyone. With UCCNC it is very easy to step OUTSIDE the box and create a very special feature unique to YOU. BUT then everyone else cannot enjoy being able to use it.

I am SURE there will be commercial adventures in UCCNC in the near future but i never go there. I try to help teh average Joe Chipslinger as much as I can.

(;-) TP
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Re: Remember Arc Lost position

Postby Robertspark » Wed Oct 19, 2016 4:54 pm

Instead of a macroloop I thought about writing a simple plugin which monitored the arcOK input pin, then every time the pin changed state from high to low (whichever was set as inactive), the plugin would obtain the dros and line number and pass it to a var, and call for a stop with deceleration, move the torch to the various var co ordinates x, and Y, move the gcode to the line saved in the var (or a variable in the plugin) call the touchoff macro, refire the torch and call for motion to start, allowing for all background stuff too THCOff and THCOn etc...

Anyone can use it then?

The faster plugin loop sounded interesting (sorry Andrew, did not mean to hijack your thread)
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2106, Neuron Lite
UCCNC v1.2105 Macro Manual
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Re: Remember Arc Lost position

Postby Vmax549 » Wed Oct 19, 2016 5:24 pm

HI Robert IF it were only that simple (;-) IF you react everytime teh ArcOK signal changes what are you going to do at teh end of a cut when teh arcOK changes state ??? OR before teh arc OK signal is established ?? With teh ArcOK signal active you will NOT need to issue a STOP as teh machine will STOP on loss of the ArcOK signal (;-) That is IF you are actually using the Arc OK signal on your machine. Some do and Some don't.

Also you cannot allways start teh Cutting at teh begining of the Current line because you may be cutting AIR and the arc will go back out. You have to wait until teh torch is ABOUT to cross teh refire point THEN fire torch so it is actually cutting as it crosses than point and there is METAL to maintain the arc on.

Just from experience it is MUCH easier to test a feature as a macro loop than a plugin AND they run at teh same LOOP HZs . THen when you are done playing IF you really need teh plugin transfer your code to a plugin and compile it .

Just a thought, (;-) TP
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Re: Remember Arc Lost position

Postby Robertspark » Wed Oct 19, 2016 5:38 pm

Ahh, but if the plugin dumps the values to vars, every time the arcOK is lost, you can have a button press onscreen which would allow you to do the arc lost, restart procedure which will use the vars saved. (Two stage operation, not fully automated)

I thought a plugin could be made to run at 100hz, but a macroloop can only run at 25hz?
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2106, Neuron Lite
UCCNC v1.2105 Macro Manual
Robertspark
 
Posts: 990
Joined: Sat Sep 03, 2016 4:27 pm
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