Multiple Arduino installation (don't need to be communicating with each other)

Hi all,

I’m quite new to using Arduino. Anyway, I have an exhibition coming up and here’s what I’m proposing:

12 Arduino units placed around the room, each connected to either a motor, turning on or off a speaker, or on or off a light.

They will all be connected to a master which will give them an order to play in. The individual units do not need to communicate with each other, they are all performing individual functions regardless of what else is going on.

MAIN QUESTION:

How feasible is this project?

SUB QUESTION:

Suggestions for a way to host 12 arduinos following the same command lines. I’m imagining each will be given an identifier and will respond to that when it appears in the sequence. Each will be active for 5 minutes or will perform it’s function (lights on) until the ID comes up in the sequence again (lights off).

I have had quite a look for something like this around the internet and these forums but couldn’t find much (maybe I didn’t look hard enough). Like I said, I’m relatively new to using Arduino and the turnaround for this exhibition is quite quick so I don’t feel I have a huge amount of time to be teaching myself how to get to this point on my own.

Any help would be massively appreciated!

Robin

What does “Arduino unit” mean? Controlers and, or driver boards?

Sounds totally feasible.

Build one, make it work, copy 11 times (I assume they're all the same kits, just maybe different sound & different light sequence). Write your code smartly so you can easily make small changes to the output without affecting the command receiving parts.

Use some kind of identification - a separate wire to each, or if you go wireless a serial number.

How do you plan on having the master send the commands to the slaves? Wired or wireless? What protocol?

Railroader: What does "Arduino unit" mean? Controlers and, or driver boards?

Controllers. Sorry, I'm quite new to this so my terminology is 'under construction' and maybe a bit all over the place. Thanks for bearing with me.

wvmarle: Sounds totally feasible.

Build one, make it work, copy 11 times (I assume they're all the same kits, just maybe different sound & different light sequence). Write your code smartly so you can easily make small changes to the output without affecting the command receiving parts.

Great! Yes, the same kits just different components. And nothing talking to anything else, only 'master - slave(x) - master'

wvmarle: Use some kind of identification - a separate wire to each, or if you go wireless a serial number.

How do you plan on having the master send the commands to the slaves? Wired or wireless? What protocol?

The room is quite large and the installation will be spread out so I was thinking wireless. I have been looking into using an RS485 shield with Modbus for the communication. https://www.hackster.io/hwhardsoft/how-to-use-modbus-with-arduino-6f434b

Again, thanks for bearing with me. I realise these descriptions and explanations are quite loose and open so your replies are very much appreciated. Got to start somewhere!

As long as it's in the same room and not more than some 50m apart the nrf24l01 modules should do the job. Much easier (and cheaper) than stringing wires around. You may even be able to run your nodes off a battery (easiest: mobile phone powerbank) for a full day. There are pretty big powerbanks available.

wvmarle:
As long as it’s in the same room and not more than some 50m apart the nrf24l01 modules should do the job. Much easier (and cheaper) than stringing wires around. You may even be able to run your nodes off a battery (easiest: mobile phone powerbank) for a full day. There are pretty big powerbanks available.

Thanks for the advice! I’ve ordered a couple of the nrf24l01 modules for a trial run and will search around for some more specific run-throughs for linking them. The room is relatively small so they should stay well within range. And that’s a good tip for the powerbanks, thanks.

I should add: powerbanks switch off when power draw drops below a certain threshold. Having a few LEDs lit all the time should do the trick to keep them alive if you run into this problem. As a result they will do well for an installation like yours (always drawing quite some power, not expecting to last longer than a day), not for a low power battery solution that's supposed to run for months or years on a single set of batteries.

Good luck with your project.

Have a look at this Simple nRF24L01+ Tutorial.

Wireless problems can be very difficult to debug so get the wireless part working on its own before you start adding any other features.

The examples are as simple as I could make them and they have worked for other Forum members. If you get stuck it will be easier to help with code that I am familiar with. Start by getting the first example to work

... R