The greatest beauty of Arduino is how cheap they are.
Are you going to be open sourcing this once you’re finished?
Beautiful work.
Well, I am done prototyping the hardware for the PKE meter and the code is almost done. There is only one thing I need to debug. While you watch the video, you may notice the one wing twitching while it’s at “rest”. That’s what the thing I need to debug. Other then that, everything works great! So expect a schematic, a list of parts, and the code to be open sourced so anyone can do it.
Here’s the video, enjoy!
Had I already told you I love you? :eyeroll:
Hear, hear!
Well the reasoning behind that decision is 2 fold. First of all, I want to share with everyone what I’ve developed for this project. Second, I am not going to build another one of these for anyone else. So if people want it, they can build it themselves but they don’t have to reinvent the wheel to do so. I just don’t have the time to be building kits for others while I have my real job and grad school to keep me occupied.
Also an update, I debugged the twitching servo, so now everything runs smoothly.
He also contractually obligated himself to do so when I asked him in chat and he agreed, and he knows I’m very litigious.
Is there any chance of getting some sound out of this as well?
There certainly is. I’m still trying to find the best buzzer for it. I had one that sounded like a duck (lol), and another one that has a nice “beep” sound to it but is too big for this application.
In fact, because you posed the question, I made a special video just for you. It highlights the larger buzzer that will probably not work in this application because of its size and the wings with no twitching.
You can check it out here.
Enjoy.
Does anyone know if the Pro Mini can do on-board playback of a sound file?
Also, I am working in conjunction with Matt to develop a shield for this thing when all is said and done, so it might become plug and play.
I don’t think there’s enough memory space. I think the best bet would be to use one of the analog pins to send a tone to a small speaker. If the analog pins are full you could use a digital pin to ping a 555 to do the same thing.
Other options would be a peizo: http://www.youtube.com/watch?v=j-FafD8TRvw
Or getting crazy: http://www.youtube.com/watch?v=liRF4alsvaI#t=3m08s
This is the buzzer I use in my PKE’s:
http://www.radioshack.com/product/index.jsp?productId=2062403
It sounds terrible normally, but it sounds like the hyperdyne one when you pulse it for a fraction of a second. I think I pulsed mine for 1/20th of a second.
You could probably get a sound ike the one in the movie out of a piezo speaker, but you’d have to record and analyze the sound of the one in the movie to figure out exactly what the waveform was shaped like. It ain’t a simple square wave, I can tell you that.
It probably can, but it would have to be a tiny sound file. There’s only 16kb of memory on it.
8000hz is probably the minimum you want to record a sound at, so that’d give you a 2 second sample. However, you have to store the program on there too, so unless you could compress it somehow it would be something less than that.
The nice thing about the PKE though is that you probably wouldn’t even need a sample thatg long. You’d probably only need a sample that is a few hundred bytes, and then you can play that back at a variable rate to adjust the pitch up and down.
Of course there are also timing issues to consider. The processor speed is only 8mhz or 16mhz depending on the model. Is that enough to play back PWM music and animate the lights? I dunno. I had a 16mhz 386 years ago and it could only just barely handle PWM.
That beep sounded fine.. I could probably downsample it for you to reduce the file size, if that is the issue…
Here’s a short video with the same buzzer that Ghost_guy has in his RGB PKE meter. I may end up using it only because of how small it is. Its a 12v buzzer but I have it pretty under powered (at 5v). Still works though, let me know what you think?
If thats what works, and fits, its good in MY book!
I’ll have to rewatch the movie to see what the actual sound sounds like.
On my PKE’s, the length of the beeps was fixed, and it was around as short as what you have when your circuit is beeping the fastest.
I’d either use fixed length beeps and go with the shorter ones, or start with the shorter ones and go faster than that. The longer beeps you have there don’t really sound like the movie meter, and might get annoying.
In fact, I’d experiment with making them much much faster. It’s possible if you keep ramping the speed up you might get a sound like the movie pke. At some point those super short pulses may begin to sound like a different note. You might get some harmonics going. Or maybe the buzzer will just get really quiet. I dunno. 
The beeping you hear is generated by the piezo buzzer, not the arduino. There’s no sample being played.
A piezo buzzer is a piezo speaker with a little chip or something in there to make it pulse at say 6500hz like that buzzer there does. All the arduino has to do to generate the sound with a buzzer is power it.
The only issue I had was that the sound was very high pitched, and my left ear hearing issue was “spidey sense tingling”
Any news?
Lots of soldering and cursing.