GearHeads Forum

Hi Cyrille:

  Yes, regular download was updated. No rush, No hurry, its there when you need it.

Art

Hello Art,

Thanks so much for this work.

I will try it the week after next (I am away from the cnc this week and on business trip next week:-)... Sorry for the delay.

Is the latest version available from the regular download location?


Cyrille

Cyrille:

  OK, just so I never forget, I added a script call for Gcode, in future to do a very exact
zero you can drop a button on the screen, Give it a variable name of say.. ZeroToProbe.

Then in the GCode library add a function named ZeroToProbe( state ).
In it you would script..

if( state ) // buttons will send two calls, one for press, one for release, so check states..
{
  GlobalSet( "InvertProbe", 0 );  //set probe normal
  Engine.GCode( "G38 Z-25 F100" ); //slow down to touch plate or probe
  GlobalSet( "InvertProbe", 1 ); //invert probe
  Engine.GCode( "G38 Z0 F1" ); //very slow rise for 1 step accuracy.
}

        That should suffice for pretty accurate zeroing. I have not tested all
this on a machine, I'm using laser mirrors at the moment as axis, so I will
leave it to you to test as you get there. Ill release in a day or two after
more testing in the code.  The only thing I haven't verified is the actual
switch of a probe as I have none hooked up. All else seems to work fine.
  IF you get tempted to use Tool Length compensation, you can set it with
G43Hnn.nnn where nn.nnn is an actual tool length. There is no tool table.

  Be very cautious in testing this, Auggie is pretty complex after one has
not worked in there for a year or two, and getting inconvenient side effects
can happen when I do intrusive additions such as these. Try your probe in
the air to simulate it all to make sure you dont crash. Your the test
pilot.

Art

Cyrille:

  I just confirmed I didnt add and script command to execute GCode. So Ill have to add a script
command to allow a G38 call. Pretty much anything else can be scripted with calls such
as Engine.ArcTo or FeedTo(.. ) etc..

  Probe however, is only accessable by Gcode, Ive been testing it in MDI calls. Hadnt occured
to me till you asked it needed to be called by script. You can invert the probe by script
but not the probe itself. I will add that before I release it.

Art

Cyrille:

  I dont think I added a way to exectute a Gcode line from script. Though you can add
scripts to GCode. In Gcode a brace signifies a switch to script.

ex:

G0X10
{
  GlobalSet("ProbeInvert", 1 );
}
G1Y12X5

  Script can be injected to the Gcode this way. But I dont think I coded the other way to add
GCode to a script. Ill look into why I didnt, there may be technical reasons.
It may be I did add it though, Ill take a look in the code, it isnt something Ive used but
I added a great deal in there thats undocumented. 

Art

Hello,

OK, I understand now...

Obviously, the "probe to 0" is, ultimately, what I Was looking for, but I can always execute the G38, and then manually set the z axis at 0. it's not like it is a complicated operation, nor is it something that is done 10 times a minute!

Can one "script" gcode excution? I mean, I can, programatically tell auggie to execute some Gcode?

Cyrille

Cyrille:

  The way it works is the command G38 is interpreted as a G1 move, BUT the probe is set
to stop the move. We dont want to lose steps, so when the probe is hit, the Pokeys
automatically switches from Auggie's trajectory planner to its internal planner, takes control
and decelerates all axis to a stop using your max accel parameter. It then switches back to
Auggies planner.
  Auggie clears its g1 move from that point onwards, and receives a
position packet from the pokeys telling it where the probe hit at.

  I dont yet give access to the hit point. So if you do a g38 xyz..F100
you will be off the real zero by the deceleration distance of the f100 move,
so by then reversing the probe signal and probing off the point with
G38Z5F1 , you will stop when the probe releases.. and with f1 as the feedrate
youd probably be off by perhaps as little as 1 step. Perhaps less.

  Conversely you could simply do a g38Z-20F1 to start with
and get pretty much an exact zero.

Eventually Ill add a button to "Zero to Probe" where the zero will be
automatically set to a offset of the probe hit point. Pressing goto zero
will then zero you to the exact point.

Art
 

Hello,

This sounds great...

Do you have an idea of the time between signal sensing and movement stop? Just to get an idea of the precision that can be obtained (not that I need too much anyway)?

Cyrille

Cyrille:

  The new G38 command seems to work well in rough testing. It is multiaxis
so one can probe with G38X10Y10Z-10 F100 and the axis will decelerate to a
stop when probe is hit. I havent done anything as yet with the hit point
data. One can I suppose set a tool by hitting a probe plate at F100, then do
an F10 , invert the probe signal and probe off with a Z move upwards. I think
I will add a way to zero to the probe hit data before I release it.

Art

Cyrille:

  Looks to me like you cracked it fine.

Im in the process of adding a G38 for probing, and I notice I never turned on
tool length offset either, so Ill see if I can attach those hooks as well. Cant promise
anything at this point,but the process is underway.

Art