Gas Sensor For Emergency Workers

As some new people are following this project each week I thought I'd post that last year it did end up receiving 4th place in the Hackaday Prize 2015 contest!

Fast Forward to 22:55 Here:

I reached out to MSA equipment a few times in hopes they would add the project to their line of equipment but they did not respond to a single mail. In speaking to one person I got the distinct impression they did not understand the concept of open-source and could take the project free of charge.

It may have also been the fact that now the design was in the public domain it would not be possible to protect it via patents :)

Hopefully someone will produce the gas sensor in the future and perhaps save some lives. This year I saw several instances (again) where multiple people died trying to rescue each other. Check out this recent example from January 2017

Cheers

Well here goes my Finals video submission. I want to thank everyone for the support and kind words so far on this project.

Thanks to Hackaday for such an amazing contest this year and thanks to the judges for all your hard work!

I decided since I already have full overview vieos, assembly tutorial videos, code explanation videos etc that I would do more of an overview video and some insight into how the project came to be, its uses and some history on me personally.

I think it turned out fairly good and covers some of the things I've been meaning to explain but never seemed to get around to doing.

Here is the video:

As well I placed all of the videos into one playlist on YouTube so people can find them easily here:

https://www.youtube.com/playlist?list=PLxyM2a_cfnzjRV7a1KZ0OlcB2G2En-1Dn

My hope is the project truly makes a differnece in the world. Best of luck to everyone in the 2015 Hackaday Prize. There are some amazing projects this year!

Cheers

Eric

Thanks to everyone for supporting this project! I'm really happy it made the top 10 and will hopefully make a difference in the world.

As I mentioned before in the project, the MQ2 sensor is great for a "proof of concept" but needs to be updated to a full sensor suite to replicate industry gas analyzers. One problem I have had is that when the sensor is flooded with a gas like LPG- it false triggers on the remaining ones whereby relaying potentially incorrect levels.

This isn't a huge deal for basic project sharing but I decided to simplify the code to a basic "Go" or "No-GO" indication. This would trigger anyone to be ready for all 3 situations if alert is indicated.

New code is added to GIT with a simple annunciation- it repeats safe if all are 0 levels and repeats "Alert" 3 times any time there is any indication of levels above zero from the sensor.

I really wish I could afford to get a proper sensor system but in the interim this is one more option to take the project forward.

I will try to do a final update video soon covering some "insider info" as to why I truly love this project and why I wish I could have used it in daily work for many years. It does indeed apply to many fields of industry and I can't believe a commercial unit like this is seemingly not yet available.

Enjoy!

Here is my "promo" video of sorts. My hope is that it will help others to understand the motivation and application behind the project. I am pretty happy with the way it turned out :)

I am still on the hunt for a proper sensor suite to replace the MQ2. I definitely want to make the unit capable of measuring all the standard gas and air quality levels that are used for commercial units. As the cost on these is extremely high I may just mod the code as mentioned before to give a strict go/no-go indication of levels with the MQ2 as the invidual level reporting doesn't work well when the sensor is overwhelmed.

Let me know what you think of the video and project. Take the design and make it better!

Finally got around to shooting the final assembly video and some testing. Overall I am super pleased with the results of this project. At the heart of it- I truly believe there is a product which can make a real difference to real people all around the word. Getting it out there completely open-source via Hackaday was just amazing timing and I couldn't be happier.

In the video you can see I switched around the transmitter module. In the next revisions I will need to get a better gas sensor (commercial grade) but in the interim I will just remove the individual gas readouts and make this unit transmit a simple SAFE, WARN, or DANGER call out for all 3.

Also thanks to comments here I will add an RGB LED so it will provide a visual indication as well in case the user is within sight and wishes to use that as an indicator. As well I will add some battery voltage monitoring with LED and voice call out as well. Very cool :)

Make one, make it better, share it back with the world! Cheers

Finally finished up the assembly video so others can easily reproduce this project for themselves. Between the assembly instructions, heavily commented code, design files, PCB layout and general project updates I think just about anyone should be able to build this project now.

The OSH Park PCB's worked amazing! I am super happy with the results considering I had zero experience in Fritzing before this project. The Fritzing files need to be cleaned up a bit for both my Hackaday projects but overall they do the job quite well.

There is the full assembly of all the electronics/PCB components. Enjoy!

Next video I'll show the assembly into the ball and some further testing/fun.

Build one yourself. Make it better. Share it back! Cheers

Just got back from 2 weeks of work in Europe so the project is behind a bit more than I would like. Did some more testing today and I have confirmed that the MQ-2 sensor indeed is not perfect for taking this project to the "next level" in commercial applications. It performs great but I can attest that with my code it has an annoying weakness with discriminating between the 3 levels if saturation is high.

With that said, it does perform great as long as you don't need discreet levels. It seems to trigger just fine- only the measurements can be unreliable as it canl announce a gas or level that isn't fully accurate (basically 2 levels will announce but only one is truly in the test environment). I am still trying to source a commercial grade sensor that I can afford to integrate- but for now I think I may just mod the code so it is strictly a go/no go indication of a dangerous condition. For this it seems to work great! No issues at all with even a slight amount of smoke or gas.

I will also try modding the code to attempt better resolution between the gasses. I have my doubts this can be done reliably. A proper commercial grade sensor seems to be the path forward but I am willing to try :)

This is simply the best part of inventing for me- working out minor hurdles and ending up better than the original target.

Next up a video of assembling the unit with my custom PCB's linked on this project. First test seems to work great!

Full assembly video tutorial coming soon! Cheers

Received the custom PCB's from OSH Park and they seem fantastic! The plan is to assemble a couple more prototypes and make sure the PCB version works as well as the breadboard ones. I don't anticipate any issues but will see if Mr. Murphy has found a way in...

I am still hunting for a higher quality sensor or a sensor suite as the MQ2 isn't the best choice for the longer term. Adding more gasses such as basic O2 would make this unit truly a beast. With the basics already done- these would be simple mod's. Will also add more LED lighting to make it easier to retrieve in the dark.

So far it works as inteneded and can't wait to see some other people take the design forward in the open source community.

Cheers

Finally got all the files posted to GitHub for everyone. Hopefully this will make it much easier for anyone else to take this project and make it their own!

In the repository you can find the full Arduino source code, the master Fritzing design file, PCB design files as well as the system design document.

PCB has yet to be tested and is noted in the "issues" section. I should receive the boards from OSHPark in a few days so I can do the final tests. So far the project does exactly what I desired!

Others should now be able to easily reproduce this wherever they may be. Hopefully the GIT repository will make it easier for future modifications and sharing of the project.

Enjoy!

Finally got around to designing a custom PCB for the gas sensor. I am entirely new to using Fritzing so I decided to simply use the Arduino Nano as it was without breaking out the chip, supply etc. This isn't the best use of space but should make this super easy for anyone to replicate.

The PCB design went really quickly and I was able to export the design files in an hour or so:

Off I went to the OSH Park website to use the credit I received from an early bird prize in the Hackaday 2015 contest. The PCB's were really cheap and I ordered- but 5 minutes later I found a serious error in the design- so I re-ordered again :)

Cheers

Eric