Growth chamber with Arduino?

Hi,

First of all, I'm a complete beginner to arduino, I have no idea how anything works, I just need to make sure what I want to do is possible before I statrt. Sorry about stupid questions, I will be very grateful to anyone who can help me here.

I want to build a growth chamber to do experiments with plants, my current setup will need to control:

14 (or 11) solenoid air valves (DC, 12V)
4 (or 3) pressure and humidity sensors
5 (or 4) air pumps (the ones for aquarium water oxygenation)
3 (or 4) lamps
1 vacuum pump
1 oxygen sensor (Seeedstudio Grove O2 sensor for example)

Will arduino be able to control all of those? I'm assuming it's just simple on/off input, but maybe I'm wrong.
Will it all fit into one arduino?
What else would I need? Somebody mentioned an amplifier for the sensor, or some additional controllers for the valves?

Thank you so much!
Peter

Will arduino be able to control all of those?

Not a hope in hell. The pressure and humidity and oxygen sensors will do what they want, with no regards to what the Arduino is telling them to do.

I'm assuming it's just simple on/off input

The air valves (controlled by solenoids) and vacuum pump are not inputs. They are outputs.

Will it all fit into one arduino?

The Arduino has no "inside", so fitting everything INTO one Arduino doesn't make sense.

A Mega can read all the sensors AND control all the outputs.

Somebody mentioned an amplifier for the sensor

Which one? What was the person smoking?

Yes, an arduino can do all of that. You have a lot of outputs, so it will need to be one with a lot of pins e.g. Mega, Due. There are ways to do it with a smaller device but for simplicity, more pins is better.

You will likely need a real time clock as well so you can follow a schedule.

Your outputs are indeed just on & off, but you'll need some external hardware to do the switching - relays or power transistor. Some of them are likely to be mains voltage (aquarium pumps?), so some means of encapsulating that would be nice e.g. power switch tail.

Your oxygen sensor does indeed need an amplifier circuit.

This is not a trivial project, especially for a novice. I'd suggest that you get a smaller arduino such as an Uno and try some learning projects where you switch a single solenoid etc. until you can see how to use each piece of hardware in isolation. Then gradually build up to your target device. The reason for using a lesser arduino is that it'll be cheaper to replace when you destroy it through some wiring error :wink:

Thanks for the answer!
That's what I was thinking about the on/off, basically the way the pumps and valves work is that if they are plugged in they pump/open, and I need another transistor that is controlled by the arduino and based on the signal, transmits power to the pump/valve (do I understand it correctly?).

I will need to turn the lamp on/off at, say, 12 hour intervals. So I need an external clock? Can you tell me what to look for? And the amplifier, what kind would I need to get?

Peet79:
Thanks for the answer!
That's what I was thinking about the on/off, basically the way the pumps and valves work is that if they are plugged in they pump/open, and I need another transistor that is controlled by the arduino and based on the signal, transmits power to the pump/valve (do I understand it correctly?).

That's it. Take a look in the playground to see how to wire such things.

I will need to turn the lamp on/off at, say, 12 hour intervals. So I need an external clock? Can you tell me what to look for? And the amplifier, what kind would I need to get?

The arduino can keep track of elapsed time, but it knows nothing about time of day, so you will need a clock. Check Adafruit or Sparkfun or Amazon - they'll all have them.

The data sheet for your oxygen sensor at seeedstudio provides you a circuit for reading it.

Ok, I'll see what they say about it, Thanks again!

First of all, I'm a complete beginner to arduino, I have no idea how anything works, I just need to make sure what I want to do is possible before I statrt.

Start with and work through the simple examples that come with the Arduino program development software, in order to learn the language and the special features of the Arduino.

If you don't, be prepared for endless frustration and destroyed equipment, with the project you have chosen.

Finally, avoid Instructables. Most of them are crap, written by people who have no idea what they are doing, but want to show that off anyway.

No absolutely, I'm in no rush :slight_smile: I will try to avoid ruining stuff as much as possible, but anyway the more I look into the electric part (the wires voltages and whatnot), the more it makes sense, it should be okay for me.
To ask one more question: if a relay or a valve is turned on (from the arduino, with the 5V output), does it stay on until I turn it off? Or do I need to look for some special ones? I need to keep some valves activated while the vacuum pump or oxygen sensor do their jobs.

An Arduino output stays in the last state you command.

If that pin is controlling a relay or valve, the same applies, as long as power is available.