Atc spins endlessly after reboot. <resolved>

[Greg]

I just built a 10 tool carousel atc for my small milling machine. I am just starting to get this setup and I ran into a hiccup I don't know how to solve. Everything seems to function as expected until I restart the machine and the carousel just spins endlessly. I have to error out and go to (ATC Init) every time I restart cnc12. I previously had swissis probe app running a tilting rack atc and I am not sure if that made some changes to something. I have made 1 change to the PLC to spin a gecko G216 for indexing.
ATC_ENABLE under definitions and
IF ATC_CarouselForward THEN SET ATC_ENABLE
IF ATC_CarouselReverse THEN SET ATC_ENABLE
IF !ATC_CarouselReverse && !ATC_CarouselForward THEN RST ATC_ENABLE


Any help is appreciated.

[Gary Campbell]

Does your carousel have a homing switch defined? It sounds like it is "driving by" the sensor

[Greg]

Does your carousel have a homing switch defined? It sounds like it is "driving by" the sensor

I was under the impression cnc12 remembered the location of the atc. Do I need a homing switch for the atc? I read through all the documentation carefully (I thought) and many threads, never seen anything about a homing switch.

[Gary Campbell]

If you have an axis designated to rotate the carousel, then CNC12 will attempt to home it via the wizard generated homing routine. With no sensor installed, the axis will rotate until the sensor triggers. If no sensor..........

If the position of the carousel is important, I recommend adding a homing sensor

[Greg]

Thanks Gary, I have a 4th axis so thats why I am using the g216 driver its a "indexing stepper driver" controlled by a couple relays. Keith has recommended it a couple times in the facebook group and Marty did a video on it, thats why I designed around this driver. I failed to mention the atc works by turning a geneva mechanism and the arm hits the sensor every index locking it into position.

The only homing information I found was for lathe turrets using the M18 macro, but I see the turretsyncbit in my list of inputs so today I am going to see if that works with a sensor. Otherwise I have not figured out how to define and use a home sensor yet.

ATC Complete v192[/img]

[Allin1Chris]

Thanks Gary, I have a 4th axis so thats why I am using the g216 driver its a "indexing stepper driver" controlled by a couple relays. Keith has recommended it a couple times in the facebook group and Marty did a video on it, thats why I designed around this driver. I failed to mention the atc works by turning a geneva mechanism and the arm hits the sensor every index locking it into position.

The only homing information I found was for lathe turrets using the M18 macro, but I see the turretsyncbit in my list of inputs so today I am going to see if that works with a sensor. Otherwise I have not figured out how to define and use a home sensor yet.

ATC Complete v192[/img]

For a Carousel Driven by outputs which seems typical for geneva mechanism carousels, Assuming that you had followed the instructions and properly initialized the ATC, should remember bin location between power cycles without the need of a home input.

On startup when your carousel starts to move, Press Alt-I and see if any of the carousel outputs are turned on for the carousel. Ideally none of them should be Green (On) until a tool change is called.

[Greg]

No issues with the inputs or outputs as far as I can tell. I noticed a possible issue or symptom the bin number switches after acorn reboot.

CNC12 manual page 352 says:
"The current ATC carousel position is constantly monitored. When there is a change, the ATC bin field in the cncm.job
file is updated and the file is saved. The ATC carousel position is read from the PLC system variable
SV_ATC_CAROUSEL_POSITION"


My job.xml file~
<?xml version="1.0" encoding="UTF-8"?>
<job_critical_data>
<FileVersion>1.0000000000000000</FileVersion>
<modal_tool_number>5</modal_tool_number>
<atc_bin_number>8</atc_bin_number> This number is updated correctly until reboot and switches to 10 every time
<atc_error_code>1</atc_error_code>
<saved_user_variable index="0">3.0000000000000000</saved_user_variable>
<saved_user_variable index="1">0.0000000000000000</saved_user_variable>
<saved_user_variable index="2">0.0000000000000000</saved_user_variable>
<saved_user_variable index="3">0.0000000000000000</saved_user_variable>
<saved_user_variable index="4">0.0000000000000000</saved_user_variable>
<saved_user_variable index="5">0.0000000000000000</saved_user_variable>
<saved_user_variable index="6">0.0000000000000000</saved_user_variable>
<saved_user_variable index="7">0.0000000000000000</saved_user_variable>
<saved_user_variable index="8">0.0000000000000000</saved_user_variable>
<saved_user_variable index="9">0.0000000000000000</saved_user_variable>
</job_critical_data>

[cncsnw]

That is the key.

The issue is a bug in the Acorn Mill PLC program. In InitialStage (around line 2577) you have this block of code:

Code: Select all

IF (ATCType_W == 1) THEN CurrentCarouselPosition_W = SV_ATC_CAROUSEL_POSITION,
						 RequestedCarouselPosition_W = CurrentCarouselPosition_W,
						 PutBackPosition_W = SV_ATC_TOOL_IN_SPINDLE

... which is intended to load the previously-saved carousel position, and the position in which to put back the tool in the spindle, for umbrella-type tool changers (ATCType_W = P830 = 1).

Unfortunately, InitialStage only runs once, at startup; and at that point in that first scan, ATCType_W has not yet been set. So CurrentCarouselPosition_W remains 0 (to be patched up to P161 -- 10, in your case -- by later carousel rotation code); and PutBackPosition_W also remains 0. I would guess that your endless rotation comes from trying to rotate the carousel until it arrives at position 0, so it can put away the tool in the spindle. Position 0, of course, never come, because the count wraps around from 10 to 1 and from 1 to 10.

I think Chris has fixed this. You could try installing the latest beta software; or you could wait for v5.08; or you could fix it yourself by making the code in question unconditional, or making it test SV_MACHINE_PARAMETER_830 instead of ATCType_W.

[Greg]

That was the problem First I did a fresh install of v5.07 rev15 beta and that did not fix the problem. I just made a simple change to

Code: Select all

IF 1==1 THEN CurrentCarouselPosition_W = SV_ATC_CAROUSEL_POSITION,
						 RequestedCarouselPosition_W = CurrentCarouselPosition_W,
						 PutBackPosition_W = SV_ATC_TOOL_IN_SPINDLE

Now everything works perfectly. I spent 2 days scratching my head. Thanks much for your help, Its much appreciated.