This will be my third year participating in science fair. So far, I’ve won at the school and district and I’ve won medals at the county science fair the first two times. This will be the first year that I can go to the state science fair! “What should I do for my science fair project?” I wondered to myself. I’d love to use my Raspberry Pi! My dad showed me a “Sound Pressure Meter” that he has to measure how loud sounds are. I wish I could turn my RPi into one of those and enter it into the Computer Science and Mathematics category.
I have a couple of USB microphones, but I don’t know how to connect to USB in Python. So, I could connect a small microphone to the GPIO pins, but I think I’d need an analog to digital converter to do that. I’d like to light a small LED if the sound level gets too loud. Then, I can go around and test bus stops, bathrooms, school concerts, and headphones to see if they’re hurting our ears. Also, I think that once I did this, then I could replace the microphone with a digital thermometer, Geiger counter, magnetic sensor, gyroscope, and other things using very similar programming.
I just ordered my mcp3008 analog to digital converter from the Adafruit store (https://www.adafruit.com/products/856). I also snuck a wireless usb device in there too. Right now, my TV is too far away from my router to be on the internet and on graphical Linux at the same time. So, I either have to be online and ssh from the laptop to command line or connect to the TV and not have any internet access. That’s a pain! Now, I can be graphical and online at the same time! I can’t wait for them to arrive!
What advice do you have for me as I work on my project? What tutorials do you recommend?
Raspberry Pi Kid 
Don’t know whether PyUSB will help http://pyusb.sourceforge.net/docs/1.0/tutorial.html in case the parts don’t arrive in time…
I’m 11 too! I was thinking about the science fair and what I could do with the raspberry pi. I will give my project some more thought, but you have definitely influenced how I might design my project. Also, I’m not sure if you knew that you could use graphical Linux over ssh. If you have never used the GPIO before, I would recommend watching this tutorial http://www.youtube.com/watch?v=q_NvDTZIaS4 Good luck, and I hope you win the science fair again!
Great! Raspberry Pi and science fair are both amazing. I decided that I can’t do the RPi project this year. I only have two weeks to finish and it is much more difficult than I thought. Don’t get me wrong, I’m still doing a project, just not with RPi. Here are some videos from my project 2 years ago: http://www.youtube.com/watch?v=RiONeNVBbk0 and http://www.youtube.com/watch?v=vjy3P7cuANw Good luck to you too!
I tried graphical linux over ssh and it didn’t work. I typed startx and the screen went black for a minute and then just went back to the command line. Maybe I’ll try it again. I have a wifi dongle for my RPi now, so I might not need to do it anymore.
I hope this is not to late.
I have been working on using startx through SSH. It hasn’t been working to well until I found xrdp. Look at this http://www.raspberrypiblog.com/2012/10/how-to-setup-remote-desktop-from.html
Hey, I know this is too late, but you might be able to use it for the next science fair. I solved the raspi to SPL meter connection problem:
http://opensource.ebswift.com/RaspiMonitor/wensn/
Wow, that’s amazing! But there’s no way that I could do all of that. It’s waaaaaaay over my head. Thanks for the tutorial, maybe I’ll try to follow it step by step.
Krystal
No worries, if you head towards the end of my article you can download the two .py files which will get you to the end result. The rest is just the methodology I used. That’s helpful if you have another device that you need to try and decode or learn how I came up with the result. It would be much easier though if you can just get hold of the model of sound level meter I used and make a modification of my sourcecode.
I hope it’s of some help for your next project :).
Cheers,
Troy
OK, I might be able to do that. I have a USB microphone, maybe I can try your files with that. Thanks!