Hello!
I'm going to start a project for fire suppression with gas, using arduino, and i have some questions about the equipment i need.
Thinking of making small room/house with a series of fire sensors and electric valves trough the room/rooms.
I want to have around 6+ sensors and valves, working independently, so if a sensor detects fire, only the valve in the area tied to the sensor will open, it can be a series of sensors and valves that will be activated at once, dependig on the layout, my point is having the fire suppression system focus an the spot where the fire started only.
Would also like to make a small illumintion system that will be shut down at the point of fire detection, and other ideeas are welcomed.
Because i never worked with arduino, and i dont have much experience in this area as well, i would like help with figuring out what hardware do i need. Is 1 arduino uno board enought to support 6/8 sensors, the activation of the valves and everything else i want to do?
What sensors should i use?
Do i need something else than sensors and board?
Do you guys have an ideea to what functions should i add to the project to make it more interesting ?
This is a college project i'm trying to do in this summer, would appreciate all the help!!
This is for a small scale house btw, not the real deal.
Thank you!
Look at commercial hood designs for kitchens. They are all mechanically activated. Hard to beat physical properties as far as reliability.
Also standing pipe designs (dry pipes). I think these sense a fire, then turn on the water to the sprinklers.
Life safety systems are some tough systems to design. Any particular reason you want to do this?
Yes, besides the college project i also want to participate at a firefighter science competition with my friend(who studyes to be a firefighter) and i also like the ideea. He will take care of building the house, providing the suppresion gas, pressure regulator and things like that, i will do the command system.
Indeed you should try to avoid electronics where possible, it's not fire proof. Sprinklers and other such systems should start operating when something gets hot - which is when electronics tend to fail - but not on a simple power outage or something else that causes the electronics to go down.
All has to be battery operated (possibly mains connected to keep the batteries charged) as you can't rely on power being available in case of a fire. It may have been a short circuit that caused it in the first place.
Tough project - and one that has seen a lot of R&D over the years already.
Perhaps you need more research. What gas will you use? Have to be non-poisonous. Have to be heaver than air. Where will you store the gas? Will the storage be more dangerous than the hot fire? Do any commercial fire suppression systems still use gas? How will your gas affect electronic components, if accidentally released?
What is the FIRST thing fire fighters do in fighting a structure fire? The turn off ALL electricity to the building. So you system will need battery backup.
Paul
I think these things work under fairly high pressure. You will have to do a dry pipe design, set the valves to direct the gas flow, then discharge the gas. It is a single discharge setup. you can't turn them on and off.
The valves will have to handle the pressure. You might want to have a manifold design - home run for each room back to the gas system, with a valve controlling each room. From a fail safe point, you might want to have all valves open, then close those not needed. If the system fails to close the proper valves, then more rooms get gas than needed instead of no rooms getting gas.
For gas systems look at www.ansul.com
Lots of questions about the gas system but if you say your partner has it handled then we don't need to discuss that here.
Have you chosen sensors you want to use? Temperature, infrared or something else?
I don't understand this part...
Would also like to make a small illumintion system that will be shut down at the point of fire detection, and other ideeas are welcomed.
Ok guys, thank you for the answers!
About the gas, we've made our research, the gas is some special inert gas, wich is not poisonous but can cause asphyxiation, this system is for comercial use, because it won't damage the assets.
One of the resons i want it to focus on the are it detects fire and not the whole room is for human safety, my friend will procure teh gass and pipes, i only need to buy the electric valves norlally closed, that should be under preassure and activate at low voltage signal so teh board can handle it( preassure wont be a problem, we will use a preasure regulator as i said).
The illumination system is so i can prove that at fire dectection, the electricity will be cut out, besides our system who will have low exposure to it.
As for the sensors , this is thea reason i asked, i would want ones that can have the sensitivity ajusted , or be precise, so not all sensors in the room will go off , only the ones in close proximity to the fire( wich wont be anything over the top, maybe we just make a electrical resistance to set fire to a small piece of paper or something like this.
There are a lot of details to figure out, but for now i just need to figure out what equipment i need because once i order its going to take a while to arrive, so it will be a problem if i will discover taht one board can;t handle all the sensors and system for example.
Once again, Thank you for your help!
Your statement: As for the sensors , this is thea reason i asked, i would want ones that can have the sensitivity ajusted , or be precise, so not all sensors in the room will go off , only the ones in close proximity to the fire( wich wont be anything over the top, maybe we just make a electrical resistance to set fire to a small piece of paper or something like this.
All the adjustments will be in your software.
I am gratified that you have done some safety research.
Paul
Ok. Sensors.
It is very tempting to use infrared sensors that can "see" the fire. But if you use directional sensors then it is very difficult to point them at every part of the room. Imagine if the fire starts in a light fitting on the ceiling: all your sensors looking down at the floor won't see it.
My favorite is temperature sensors. A grid of thermometers across the ceiling will detect most fires reliably. So the problem becomes: how do you connect 5-50 thermometers to the Arduino? The DS18B20 is a "one wire" sensor that only needs one data wire to connect an unlimited number of sensors to the Arduino.
The hardest part of using the DS18B20 is programming a way to identify which sensor is in each physical position. I have a setup menu on my controller which shows all the sensors on the bus with their temperature. Heat up one with your hand and look for the one which changes. Now you know the internal ID number for that sensor.
MorganS:
Ok. Sensors.
It is very tempting to use infrared sensors that can "see" the fire. But if you use directional sensors then it is very difficult to point them at every part of the room. Imagine if the fire starts in a light fitting on the ceiling: all your sensors looking down at the floor won't see it.
My favorite is temperature sensors. A grid of thermometers across the ceiling will detect most fires reliably. So the problem becomes: how do you connect 5-50 thermometers to the Arduino? The DS18B20 is a "one wire" sensor that only needs one data wire to connect an unlimited number of sensors to the Arduino.
The hardest part of using the DS18B20 is programming a way to identify which sensor is in each physical position. I have a setup menu on my controller which shows all the sensors on the bus with their temperature. Heat up one with your hand and look for the one which changes. Now you know the internal ID number for that sensor.
Can't you have each sensor paired with the valve in it's proximity? And if i'm going to use these sensors i need only the board, sensors and some wires right?
I guess the best way would be to have the infrared sensors, and some aditional temperature sensors that cover the blind spots, Lets say aroud 6/8 infrared and 3 temperature sensors should do it, what do you guys think?
What i;m asking is kinda like a shoping list of all the parts i need to make this work.
Until now i know i need to buy the sensors, an arduino uno board, bunch of wires, a buzzer would be great, a display(maybe? just to show the state of the sensors).
As far as sensors go, how many do you want in a room? How many "zones" in a room for the gas? If you are going to use a low pressure system, I doubt it will have the ability to target a specific spot on the floor and extinguish it (like a fire extinguisher). You will have to flood the room to displace all the air.
You need to do a lot of trial and error to figure out what works. Build a test room. I don't think scaling will work. It will need to be full size. Light a fire on the floor and see how big it needs to get (or how long it needs to burn) before you can detect the heat on the ceiling.
crysty1810:
I want to have around 6+ sensors and valves, working independently,
6 valves sounds do-able.
Have you found any suitable valves yet? You are going to find they are all higher voltage than the Arduino. Like 12V or 24V. So the Arduino must control that higher voltage. The easiest way is to use relays. Modules with 1 or 4 relays are very common. I suggest you buy two modules of 4. Then use one relay as the "power cut" relay.
Directly controlling 8 relays will take 8 Arduino pins. If you are going to have a lot more then you need a different control method.
The whole thing is ment to work on a small scale, being a project, and a demonstration of concept. So let,s say im going to have 3 rooms,let's say 2 rooms around 30x30cm , a small one , half that, and a hallway maybe? or a bigger room around 80x80 cm, didnt decide yet. 8 infrared and 3 temperature sensors should be enought.
I have found some valves that work on 12v,i'll have to look it up more
Maybe i could use something like this, like 4 of them in a big room?
Not to burst your bubble, but what concept are you trying to prove?
That a temperature sensor will pick up the heat from a fire at a couple of inches? That is already done. Will it pick it up at a couple of feet? Might take a bit of work. How about 8 to 10 feet? Doubt it.
Another thing that you will have to find out is if the precharged gas system will maintain pressure or will it leak? And then if it is a low pressure system, will it supply enough gas to do the job at full scale? Easy to fill a small box, but will it fill a room with openings.
I'm not saying don't bother. Coming up with new ways of doing things is what it is all about. But physics gets in the way of a lot of good ideas. Need to put the effort on things that need overcoming, not just turning on a valve or two.
I'm not trying to prove the sensors work... I'm not trying to reinvent the wheel... I just want to put what i learned in college to practice, in a fun little project, done by me. To make a small scale fire suppression system with gas and make it as interesting as i can. And the gas system is not my area, my friend studies these kind of things, and has it all figured out. Again i dont need to prove that my small gas suppresion system will work on full scale with the same equipment, ofc it wont, its ment to work on my small room, for full scale you would need a whole different system.
I just want to make the whole thing work on my small scale room/s, and i dont know what hardware do i need, that's why i need your help :).
I will figure out the obstacles later, for now i just need to know what parts to order to start my project.
MikeLittle:
Not to burst your bubble, but what concept are you trying to prove?
That learning for the sake of learning is a laudable goal.
At least that's what I see.
It is a good idea. Big difference between just trying to do something for the sake of doing it and having to deal with industry constraints. Doesn't need to be battery operated, which impacts valves used for example. It is a scaled model, so sensors won't be an issue.
