Digital Dohicky - Laser Power Meter (Part 1)

[@madeverell]

Robert really like your videos and looking forward to the next CO2 laser video. Between you and Russ I have learned a lot about them. Thanks and keep up the work!! Mike

[@RobertCowanDIY]

Thanks!

[@petergilliard1981]

Hi Robert. Great project and right up my alley so to speak. I'm looking to develop a hand held measurement device for use in the therapeutic laser field and this fits the bill perfectly. by the way, yours is a slick professional demo.

[@MikeBramm]

Boy, this sure reminds me of the Friday New Product videos you did at Sparkfun. I miss you over there. Glad I found your channel.

[@RobertCowanDIY]

TELL ALL OF YOUR FRIENDS! ;-)

[@JonPrevost]

Measuring the tube directly is good to see about tube condition but ultimately what is more important is the power after the mirrors and before the lens. This would tell you if your mirrors are dirty.

[@mpilley22]

Where is the other video

[@Madeinoz1967]

Watch out taking a reading at the end of the tube like that, I did and reflected power killed my tube mirror, ended up getting two beams coming out of it instead of a single nice beam - had to get a new tube :(

[@sapneshnaik]

for calculating test time, you can also try and measure temperature rise per second, higher the temp lower the run time.

[@snjmedical6563]

0:14 Hello, Robert! We are a laser manufacturer from Korea. Can you let us know what a little device name is which you hold 0:14? Where did you purchase it and how we can purchase it?

[@RobertCowanDIY]

Hello. Talk to Russ at his channel: kzbin.info/www/bejne/ooCco4qipMd_kLc&ab_channel=SarbarMultimedia He custom makes them. If you are a business, you might want to just buy a 'real' laser power meter, like he shows in the video.

[@udarajayasundara7460]

why did you multiple by 2? what is the logic of two-to-one ratio

[@dacostad]

Just ordered the DoHikey so I am very interested in this project.

[@reconbuzz8141]

Where did you go to get it

[@motoguy1]

Do additional videos exist on this project?

[@RobertCowanDIY]

Nope, unfortunately. It's one of those strange projects where you really only use it once every 6 months, so I lost interest in it. I still have it in this same form though and occasionally use it just like this ;-)

[@juntendo6104]

Very informative. I feel like there's just too much inconsistancy. The laser wavelength would have different absorption spectra and heat up differently.

[@qigong1001]

Robert, what would you use to test energy/emission from infrared led diode (non-laser), in one direction. I don't need to measure all the power coming out, just the energy incident on a sensor on one side of the diode. Thanks.

[@RobertCowanDIY]

I would have no idea how to test that...

[@cnclaser3866]

Hi beautiful meter? do you sell this or can I make it myself? with info from you?

[@arzie2000]

is there a specific time you have to expose the probe to the laser beam? as far as i know, the longer you expose the probe, the higher the temperature. how would that affect the accuracy of the reading? also, are you willing to share your source code? thanks.

[@georgx7759]

Where you buy the probe with the black round case? Or is it selfmade?

[@greenacresfarms]

Where can I get the puck? I have a thermistor on my digital multimeter that I can use to measure the temp differential. Also, how long do I laze the puck?

[@RobertCowanDIY]

Check the video in the comments. All will be answered by watching that video.

[@tugaminhoto4969]

Where can buy or how maje the probe?

[@MarcelHIC]

when do you continue the stratasys series?

[@RobertCowanDIY]

Soon? I'm really busy with other projects. But I really want to get the printer working.

[@notsogreat123]

Ever think of using some kind of voltage regulator ?

[@troygamm4035]

Is there a Part 2?

[@RobertCowanDIY]

nope, sorry, I never took this any further :-/

[@TheSchnibbi]

what are durations in the laserbeam for your setup ?

[@RobertCowanDIY]

Check the links back to Russ' video. They vary depending on the wattage of your laser. There are separate programs that run a specified amount of time.

[@brian2k1]

Is there a video on those metal part boxes you have behind you? Could you give up some details on those? I see them offered by a lot of vendors but not with a nice rack and wood top like you have. Also curious or which brand you chose for the metal containers.

[@RobertCowanDIY]

No, but I might do a shop tour video and those would certainly be covered. They're made by Durham Manufacturing. I added the wood tops.

[@hyperhektor7733]

I cant find Part 2 , is it already published ?

[@SamBirchenough]

What do you do for a living? Where are you located? Keep up the great videos man!!

[@ricksantos8178]

Robert, Great Job and thank you for the shared info! Did you finish it? I'm trying to find part 2 but couldn't find.

[@RobertCowanDIY]

I didn't finish it yet, I've been busy with other projects. I hope to get to it soon, too many projects and not enough time!

[@MrEzz00]

Hi Robert I too have got the doohickey from russ and was thinking of doing the exact same thing as you would it be possible to get your scotch as I am quite a novice with arduino but do get there eventually regards Eric

[@AhmedIbrahim81]

Could you please share the wiring diagram?

[@RobertCowanDIY]

It should be all commented in the code.

[@juniunogueira3032]

How would you give us the scheme of this display paste

[@RobertCowanDIY]

I'm not sure what you're asking.

[@Aga-Bubamara]

You may check mine kzbin.info/www/bejne/kJmzm4OLi9OKotE at the very end there is another video link where I test it and calibrate it..

[@ccomito1223]

Nice work! Do you have a pinout available? I like the breadboard version... :-)

[@RobertCowanDIY]

I don't, but if you check the code, I should have all the pins defined.

[@ccomito1223]

I was able to watch your video and draw the pinout as I went. There's a green wire that goes to the upper left corner of your breadboard that I can't see. It looks like it comes off one side of the switch but I'm not sure where it goes. Any ideas? Thanks for the response too!

[@RobertCowanDIY]

I think that just goes back to ground on the arduino.

[@JonathanRansom]

Idea for version 2, servo controlled. Servo drops sensor in the laser beam and microcontroller fires laser for an amount of time. Then displays results on screen.

[@RobertCowanDIY]

Eh, it's not something you do often and there's not much room in the back of the printer. I'm opting for a hand-help device instead. I don't intend for this to be my last laser ;-)

[@JonathanRansom]

I get it. I don't have a laser (yet), I thought it was something you would want to do often.

[@RobertCowanDIY]

Nope, it's only done once in a while. You do it to just check that you're getting the right amount of output, maybe once every 6 months or so.

[@dumle29]

Instead of a fixed scaling, why not just have a target temperature, and meassure how long it takes to reach that?

[@RobertCowanDIY]

This would mean you'd have to start the program at the exact same time as the meter. You could possibly use it to detect a temperature rise, and then use that as the starting time, but that gets a bit tricky. Essentially, you always need to control or measure temperature rise over time. I chose to control this in the laser program. In every other case, you'd need to synchronize the meter and the laser, which gets trickier.

[@dumle29]

Ah, that makes sense. I suppose you could have an optical sensor looking at the puck, which could detect the laser dot, and start the timer, but that's more complex again.

[@RobertCowanDIY]

Yeah, but I'm not sure what problem that's solving. It's very easy to just run the laser for a set time and record the temperature rise. It's a very simple process that you really only need to do once a month at the most.

[@TheHelicapt]

Is this something you can make and sell ? I’m not tech enough to build one.

[@RobertCowanDIY]

I do not. But you can use the simpler one (you just do the math by hand). Check out Russ' KZbin channel, you can buy them directly from him, the link to his channel is in the description.

[@TheHelicapt]

Robert Cowan Any chance of part 2 to show how to put it together?

[@10joel1]

What laser cutter is that?

[@RobertCowanDIY]

I forget the brand, but it's a "US" made laser (basically a chinese machine with upgrades performed in the US). It's a 60W laser with linear rails, steppers, and a roughly 24x18" cutting area.

[@10joel1]

Did you have to make any modifications to the laser cutter to make it work properly?

[@RobertCowanDIY]

not really. I swapped out the controller because it was a bit dated. I got the laser used on craigslist, it retails for around $10k, so it's a higher quality laser and the components were nice. I also had one of the cheap chinese 40W lasers and it needed several modifications to be usable. I added an air assist, better exhaust fan, better pump, lights, and new focusing lens.

[@georgeyork8975]

Robert Great project I figured I could use, however when tried loading the sketch to the arduino pro mini it gives and error code of "SparkFunMAX31855k.h: No such file or directory".Arduino: 1.8.9 (Windows Store 1.8.21.0) (Windows 10), Board: "Arduino Pro or Pro Mini, ATmega328P (5V, 16 MHz)" DD_main:2:61: error: SparkFunMAX31855k.h: No such file or directory compilation terminated. exit status 1 SparkFunMAX31855k.h: No such file or directory This report would have more information with "Show verbose output during compilation" option enabled in File -> Preferences. I am thinking maybe its because the board is a clone possibly? not sure please advise on your thoughts regarding this. Thanks!

[@RobertCowanDIY]

Did you download the library? "DD_main:2:61: error: SparkFunMAX31855k.h: No such file or directory " this means you didn't install the library.

[@georgeyork8975]

@@RobertCowanDIY I thought I did ....

[@georgeyork8975]

is the library in the same area?

[@georgeyork8975]

@@RobertCowanDIY i downloaded the main code where would the library be?

[@RobertCowanDIY]

@@georgeyork8975 check the product page or use Google

[@cheerry7]

THANK YOU!!!!!

[@StuffWithKirby]

Alot smaller than the old one I use at work. Mine takes up a briefcase

[@FrankSandqvist]

A battery doesn't sound like a very good reference however? The double A's will go from 1,6 to 0,9 depending on how much juice is in 'em. I think you should add some sort of absolute reference like a diode. Unless I'm missing something. :) Anyway awesome video as always!

[@RobertCowanDIY]

It just needs to be stable and relatively low noise. It doesn't necessarily need to be a strict voltage (at least from my understanding). The USB was very noisy, which threw off the readings. A battery worked as reliably as a bench power supply.

[@FrankSandqvist]

Robert Cowan Ah, okay, I see

[@dumle29]

Microcontrollers have an internal voltage reference most of the time. A diode is actually pretty bad as a voltage reference, as their Vf varies a lot with temperature

[@RobertCowanDIY]

Yep, once again, it's not necessarily that I need a voltage reference, I just need a clean and stable voltage. The reference is done in the thermocouple chip. It just needs a stable and noise free supply.

[@blenderbuch]

Why not just wait/time how long it takes to get 10K (or 20K or whatever) raise and use this as values? After this let it beep so the user removes it before it gets to hot. No need to scale or make a UI this way.

[@RobertCowanDIY]

Good question and good idea. I guess because there's not a good way to control the laser for a set period of time... I'll think about it more, but you can't really just tell the laser to run for xx number of seconds at a certain amount of power.

[@vedranlatin1386]

Draw a big spiral all over the worktable and select slow feed? That should keep it busy for a while :)

[@ricardrinaldo4791]

Not sure if you saw Russ´s video about max power but running these chinese tubes at max (100% in the dsp) might be a bad idea. The mA output may very well be above the recommended max for the tube and in his machine there was no power output increase from 80% and above. You will end up shortening the life of your tube, just a heads up. :) Great job and a very cool project though, I wish I had more time and knowledge in programming. What laser do you have, link? Regards

[@georgeyork8975]

Or maybe it has something to do with the gitfiles such as the gitattributes and gitignore!?? Not familiar with this...maybe this is what is required!??

[@JAKOB1977]

where the f are part2 part3 part4 part5,, I know you're hiding them..come on.! get in motion.