Implementing LASER INTENSITY

Gigio

Hi all !
I'm trying to implement laser intensity routine, i have a laser driver with a TTL input so,
i try to modify source from :

WRITE(LASER_PIN,(LASER_ON_HIGH ? newIntensity > 199 : newIntensity < 200));

to

analogWrite(LASER_PIN, newIntensity);

But nothing change ! :/
PWM 255 = ON
PWM <255 = OFF

i also try
m42 p44 s254 = ON 
m42 p44 s254 = OFF

Any ideas ?

Here the simple code :

void LaserDriver::changeIntensity(uint8_t newIntensity)

{

if(EVENT_SET_LASER(newIntensity))

{

// Default implementation

#if LASER_PIN > -1

//WRITE(LASER_PIN,(LASER_ON_HIGH ? newIntensity > 199 : newIntensity < 200));

// set PWM wave to TTL laser-driver input

analogWrite(LASER_PIN, newIntensity);

#endif

}

}

Gigio

(*) typo

i also try m42 p44 s255 = ON m42 p44 s254 = OFF

Gigio

Repetier

You should implement it using the event system as described.
EVENT_SET_LASER(newIntensity) would then change intensity and return false to prevent default code from doing on/off.

2. You need to learn about PWM. The pin must have a PWM time to use analogWrite with analog value. Moreover it must be one that does not use Timer 0,1 or 2 and eventually 3 if you have beep enabled. These are already used internally.

3. Make sure to have a high PWM frequency. It will turn laser on/off and to hit every spot you need a light on phase every 50% spot diameter.

Gigio

1) Ok no problem , i was in rush so now i have implemented it with this 2 small changes

https://drive.google.com/file/d/0B7VPQ4zmKBz4Q3VkQTJBdVlLX0k/view?usp=sharing i think now the code is clean and correct write , right ?

2) ok , got it , i try one precoded library : https://github.com/chipaudette/ArduinoPolySix/tree/master/ArduinoLibraries/Timer5 and use for safety the pin 44 on timer5 (i think pin44 it will beh good and often free)

3) ok now i have all i need but the driver specs. So, i can controll frequency , duty cycle, wave form and so on.
Someone know wich values are good to use as "m3 s1" and what for "m3 255" ?
I mean, what kind of wave form, frequency etc... to use as good range ?

Thanks

when i get something good to show i'll do! Until now is a pretty "dirty working code" ;)

Repetier

No that wa snot what I meant with event system. See on github src/SampleEventSystems/Felix Pro 1

In configuration.h or in online tool in manual commands you add

#define CUSTOM_EVENTS

then it will read the files

CustomEvents.h

CustomEventsImpl.h

the first file would have your define modified liek

#define EVENT_SET_LASER(intensity) SetMyLaserIntensity(intensity);

in the latter you have code like

bool SetMyLaserIntensity(uint8_t intensity) {

// Do your work here

return false;

}

That is how the event system works.

As you see this does not alter the original repetier files at all, so you can simple download latest version and recompile. Your solution still requires modification after each update, which is what we wanted to prevent with the event system

Just for completeless, best waveform is full power and use feedrate to control power, which is the default implementation.

If you want to switch choose the wave form with the most switches if the laser can handle it. So for 50% it is better 10000 times on/off per second then 10 times.

Gigio

ok perfect i agree with the first part of you post, for this reason i didn't post any code yet :)

after that you say :

"Just for completeless, best waveform is full power and use feedrate to control power, which is the default implementation."
and now start the problem, InkScape plugin , and other laser software support in most case "pwm" instead "feedrate" , so, i think is most important to have a firmware that can handle PWM than modifiy by hand (read python scripts) an "laser Gcode" file for work with FEEDRATE !

If u know some software that produce gcode with feedrate from a greyscale image, free fell to comment ! I give u a "virtual-beer" ;)

So, thanks for all the hint, now if i find spare time i try to write a clean code and show you what i get for work with a TTL driver and use a PWM value [0..255] as input

Thanks !

Repetier

Speaking about inkscape, have a look here:

http://www.repetier.com/repetier-g-code-plugin-for-inskscape/ </div><div>

Just made today:-) Creates only contours but creates our gcode how we like it andis super easy to use.

With the grayscale image - do you have a nice plugin that does it. I'm still searching one that I can modify like the above plugin (which is a existing gpl plugin I modified to our needs). Maybe then you get one that does feedrate based.

Gigio

lol I modified the same python plugin for work with feedrate and analogue value ahahaha
was based on : J Tech Photonics Laser Tool http://jtechphotonics.com/?page_id=2012 i noticed same minor bug in gcode creation (some G0 instead G1 and some "F{value}" erroneus next to G1 code...
if i find the log i let you know

about the greyscale i used this : https://hackaday.io/project/4828-raster-2-laser-gcode-generator the code is pretty easy to hack for feedrate and the result is pretty good but maybe need to increase the resolution up to 10pixel/mm, 10 still a bit far , 15/20 maybe will be better.

Gigio

Ok as expected same bug afflict your version :

J = original plugin
R = your

Same F command next to G1 line

Gigio

and here is the gcode interpreted :

Gigio

And here a quick fix :

dirty gcode :

Fix the "F" bug

I hope this help someone with same problem !

Gigio

Still some small difference with visualizzation and actual "print" but is a good and easy plugin

About the grayscale ?
Wich one you like more ?
What about this : https://hackaday.io/project/4828-raster-2-laser-gcode-generator ?

Repetier

The F bug is a good hint. Checked the code and it was quite easy to find. Now our plugin does not have that error any more as it seems. Thanks.

The greyscale plugin will have to wait a bit. I'm currently with a other thing busy, but have it on my todos.

Gigio

No i say thanks all the repetier stuff !!!
Also my delta printer say thank to you :D

The use of HAL in the firmware put this 10time ahead the classic marlin (y)
Really, we push it around 400mm/sec 10'000 accelleration (only for test purpose) and only Repetier can handle the math needed on a poor mega+ramps 1.4 (y)

Gigio

keep talking about your plugin,
here my fix :
- insert Fcommand before g1 g2 g3 mode
- insert G28 and Custom Z on header and footer (please remove)

this help me modify the speed from repetier host , if i use your code , every speed modify seems to have no success.

http://www.g2kweb.it/public/images/repetier.rar in the maintime : Happy holidays !

PeterPeter

I have also worked on this Plugin and found the same errors. At the end, maybe we should compare our improvements :)
- Peter

NFAZ10

Is there a link to the completed code for laser intensity? I would love to beable to adjust the lasers power!

lucasss

Repetier wrote
Speaking about inkscape, have a look here:
http://www.repetier.com/repetier-g-code-plugin-for-inskscape/ </div><div> </div><div>Just made today:-) Creates only contours but creates our gcode how we like it andis super easy to use.
With the grayscale image - do you have a nice plugin that does it. I'm still searching one that I can modify like the above plugin (which is a existing gpl plugin I modified to our needs). Maybe then you get one that does feedrate based.

Not working properly on inscake 0.92.
The script does not respect the object dimension...seems a dpi problem...2
Can you pls solve? Or you could remove "Install the latest version of Inkscape" from the web page...

http://forum.inkscapecommunity.com/index.php?topic=486.0

Repetier

I have put it on my long todo list and made a notice to use 0.91 which I think should still be working.