Auggie Early posts

[GlennD]

Moose
Thank you for the link.
LaserDRW. 
Have made a couple of things so far.
Etched some glass and did a rubber stamp for my wife.
Etched 20 wooded canteen faces for a charity for the local college alumni.

The company I currently work for bought a DSP controller(LO-RD5) for me to try out since I am doing some stuff for them from home.
Made a single sided board so I can go back and forth between controllers if they want it back.  [url]http://www.lightobject.info/viewtopic.php?f=8&t=2889[\url]
Not really excited about it either though it does work and the documentation is a little better.  No hasp to run the software either.

[GlennD]

Ya-Nvr-No
Looks great, my gantry not near as cool looking.

Moose
Should mention the RD5 DSP won't let you do grey scale if you have a CO2 laser selected.

Glenn

[ArtF]

Glenn:

I wonder if its a co2 limitation..or if its more that co2  lasers can be tempermental at triggering in lower power
levels.. mine wont turn on under 20% for example..

Art

[GlennD]

Art
Here is what Marco over at Light object posted.

I was told that the R5 support "gray scale" engraving but when I tried it on regular CO2 laser, I didn't see the effect. I talked to Mr.Xiao and he told me that the feature only available when running "RF" laser. The delay on CO2 won't be able to show the grayscale effectively on the engraving.

I was half tempted to try the RF setting with out pre-ignition, to see if I could do grey scale but not sure what it would do to my tube.  My tube fires with the controller set to 9%.

Glenn

[ArtF]

Glen:

  I suspect highly the problem is one of nonlinearity, something one could conceivably
correct for with proper calibration but with no guarentee's of performance which would
likely vary form tube to tube. I base this suspicion on the way my laser works, where the on/off
is very fast with as much as over 1000dots per inch, so hysterisis doesnt appear to be
the issue, but Ill bet linearity is (based on linearity tests Ive run on my glass co2 laser
vs the rf one..)...
  Ill be facinated to hear how that works out on co2 tubes vs the rf tube Ill be initially
hooking up. I also have 2 other co2 lasers, one glass and one ceramic that I can eventually
attempt to control to see the effect...

  There are other ways to get get scale though without varying power, simply varying speed
and frequency would provide a decent grey scale as power is in linear proportion to speed
in its effect. Sounds like lots to play with when we get going.  :-)

  Art

 

[Mooselake]

Kinda related, if you do some googling (start with grayscale laser photo engraving)  you can find a number of articles on how to get grayscale results with dithering (the photo variety, not the Moose version).  LaserDRW has a (undocumented, of course) "pixel" option in the engraving properties that seems to control the size of a block used to implement dithering within the software, that might eliminate the need to use external software (GIMP, for example) to preprocess images.  I've tried it for engraving glass and it looks promising.  It interacts with power and speed settings so needs more experiments.

I'm getting mixed grayscale results overall, but that's due mostly to a more random than systematic approach, my issues are more related to getting the speed and power settings just right and not having the spare time atm to do some extended sessions and sort it out.  Wanting to try engraving on every kind of odd material can find isn't helping, either.

Kirk

[ArtF]

Kirk:

lol, I get sucked into that as well. Too many cool things to see what happens on.. :)

Art

[GlennD]

Kirk
The manual for RDworks has a section on dithering, I will check it out. Thank you.
So much to learn so little free time. 
I haven't been able to touch the K40 for the last three weekends working on getting printed parts done for the laser table or doing honey do's.

I was going to say can't wait till I retire, but I don't know any one currently that is retired that has much free time.

Glenn

[GlennD]

Went back and read Arts post to my Marco post and,,,
What are you checking for linearity?
I would guess it would be the PS output versus the PWM input.
Not sure if you would check the motor speeds with that or what.

Pretty much all of the stuff you do Art is over my head but learning is fun.
My electrical training is self taught although I played and electrician in the army. :P

Glenn

[Ya-Nvr-No]

to go along with Arts recent Constant Velocity training video here is a square plotted at incremental angles, I was testing waveform consistency and that the pencil plotter tracked well at various feeds & cv settings.


https://www.youtube.com/watch?v=fKp5jbWVzUE


My code; run from the script window:

sleep(5); //gives me some time to get to the machine to watch.
Engine.RapidTo(0, 0, .2); //X,Y,Z start position
block("MotionStill");   // wait for it to get there

Z=0;
for(i = 0; i < 90; i = i + 10)
{
startang=i/2;

for( x = startang; x < (2 * (Const.PI))+startang; x += (Const.PI/2) )
&nbsp; {
&nbsp; &nbsp; &nbsp; Engine.FeedTo( 2 * math.cos(x), 2 * math.sin(x), Z, A );
&nbsp; &nbsp; &nbsp; print("X:= " + 2 * math.cos(x),"Y:= " + 2 * math.sin(x));
&nbsp; }
Engine.RapidTo(X, Y, .2);
}
Engine.RapidTo(0, 0, .2);
block("MotionStill");


Then this is a typical log file output, the X & Y are from my script print() function.
the Line : Vel:- , Accel:- &nbsp;-- Commanded - are from Auggies data stream using the current settings from my setup.


X:= 2 Y:= 0
X:= -8.74228e-008 Y:= 2
X:= -2 Y:= -1.74846e-007
X:= 2.38498e-008 Y:= -2
X:= 0.567324 Y:= -1.91785
X:= 1.91785 Y:= 0.567325
X:= -0.567325 Y:= 1.91785
X:= -1.91785 Y:= -0.567324
X:= 0.567324 Y:= -1.91785
X:= -1.67814 Y:= -1.08804
X:= 1.08804 Y:= -1.67814
X:= 1.67814 Y:= 1.08804
X:= -1.08804 Y:= 1.67814
X:= -1.67814 Y:= -1.08804
X:= -1.51938 Y:= 1.30058
X:= -1.30057 Y:= -1.51938
X:= 1.51938 Y:= -1.30057
X:= 1.30057 Y:= 1.51938
X:= 0.816164 Y:= 1.82589
X:= -1.82589 Y:= 0.816163
X:= -0.816162 Y:= -1.82589
X:= 1.82589 Y:= -0.816161
X:= 1.98241 Y:= -0.264704
X:= 0.264702 Y:= 1.98241
X:= -1.98241 Y:= 0.264701
X:= -0.2647 Y:= -1.98241
X:= 0.308503 Y:= -1.97606
X:= 1.97606 Y:= 0.308504
X:= -0.308505 Y:= 1.97606
X:= -1.97606 Y:= -0.308507
X:= -1.80738 Y:= -0.856365
X:= 0.856367 Y:= -1.80738
X:= 1.80738 Y:= 0.856368
X:= -0.856369 Y:= 1.80738
X:= -1.33388 Y:= 1.49023
X:= -1.49023 Y:= -1.33388
X:= 1.33388 Y:= -1.49022
X:= 1.49022 Y:= 1.33388
Line : Vel:5.03 , Accel: 150.80 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 8485.28 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 8485.28 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 8485.28 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:1.52 , Accel: 45.53 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6828.72 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 12565.91 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6828.72 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 12565.91 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:6.01 , Accel: 180.17 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 28758.73 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6135.01 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 28758.64 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6135.01 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:6.01 , Accel: 180.17 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6018.03 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 77560.97 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6018.03 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:1.52 , Accel: 45.53 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 16807.08 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6423.25 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 16807.02 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:1.52 , Accel: 45.53 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 7552.18 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 9879.79 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 7552.18 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:1.52 , Accel: 45.53 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 7428.35 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 10176.89 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 7428.34 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:1.52 , Accel: 45.53 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 17844.62 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6370.93 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 17844.69 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:1.52 , Accel: 45.53 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6009.19 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 90137.82 &nbsp;-- Commanded 8.33
Line : Vel:8.33 , Accel: 6009.19 &nbsp;-- Commanded 8.33
Line : Vel:0.50 , Accel: 15.00 &nbsp;-- Commanded 1666.65
Line : Vel:14.99 , Accel: 8996.32 &nbsp;-- Commanded 1666.65

[Ya-Nvr-No]

Easier for me to create in degrees; &nbsp;;D

Z=0;
start_ang=math.degtorad (0);
inc_ang=math.degtorad (60);
fullpath=360/inc_ang;
acrossflats=1.5;
toflat=(acrossflats/2);
print(start_ang);
print(inc_ang);
print(fullpath);

for( x = start_ang; x < ((2 * Const.PI)+(Const.PI/fullpath)); x += inc_ang)
&nbsp; {
&nbsp; &nbsp; &nbsp; Engine.FeedTo( toflat * math.cos(x), toflat * math.sin(x), Z, A );
&nbsp; }

Engine.RapidTo(0, 0, .5);
block("MotionStill");


8)
Note: MotionStill is a command that waits till the coordinates have been reached, pauses slightly then continues.
Even thou cv is on and radius is set to .01" in this next code example it acts more like exact stop mode.

for( x = start_ang; x < ((2 * Const.PI)+(Const.PI/fullpath)); x += inc_ang)
&nbsp; {
&nbsp; &nbsp; &nbsp; Engine.FeedTo( toflat * math.cos(x), toflat * math.sin(x), Z, A );
&nbsp; &nbsp; &nbsp; block("MotionStill");
&nbsp; }

If i was having any more fun, Art would be charging me. ;)

[ArtF]

:) .. much better.

I really must get my machine hooked up..

Art

[Ya-Nvr-No]

Hell no!&nbsp; :D your too busy coding, I have a lot more for you to do ::)

[DanL]

you boy's are having too much fun, look very cool art

[ArtF]

His machine is actually moving, I have a stepper 4th axis behind me that runs so I can listen to it.
So I swap it among axis .&nbsp; Wont be long Ill have to hook mine up to the laser arms..
:)

Art