Pulling lots of wire vs remote monitoring via wifi

Hello, I'm looking for advice on how you would set this up.

My situation: I have a boat with a bridge where my electronics, steering and control is located. This is where I spend my time while piloting the boat. I am looking to install many sensors below deck in various locations. The wiring for them would all aggregate in the engine room where it would all come up a conduit to the bridge. Pulling wire through that conduit is not easy. I was looking at pulling one multiple strand wire (or two or thee) rather than 12,24 or 36 individual paired strands.

Then I thought... This is dumb,. Why not run it all into one or more arduinos that would connect wirelessly to the bridge rather than pull all this wire.

Ideally I want to set up something like Statusboard that will allow me to monitor all this sensor info on a ipad. So I'm going to have to aggregate the signals somewhere, process them and make available to Statusboard. It would be nice to sit on the bridge to do a lot of the connecting, programming and testing rather than the dungeon engine room. But pulling all that wire will suck big time.

Just looking for thoughts as to how you would approach it.
Many thanks
Michael

I don't know what sort of environment your boat will be in, but a radio network would be vulnerable to interference from devices around you. When you're out in the middle of nowhere that shouldn't be a problem, but I guess you want this thing to keep working when you're moored up and who knows what other radio sources will be in that environment. If you have the means to run a cable, I suggest that an Ethernet cable would be the way to go. It means you have effectively unlimited bandwidth available for sensor readings or anything else you want to use - it also gives you the option to use standard Ethernet devices such as web cams, digital entertainment systems and so on. Preferably keep power and data cables separate, but if you can achieve that then with power and Ethernet available you have the potential to do almost anything.

You haven't told us how many "many sensors" is. 10, 100, 1000, 1,000,000? A guestimate would help.
You haven't told us what these sensors are and how often they need to be read. A temperature sensor probably only needs to be read once a minute, whereas an accelerometer, to measure pitch and yaw, would have to be read almost continuously.

To echo PeterH's reply, an Ethernet cable would probably do what you need and also have the capability for 2 way communications - you could send data/instructions back to your Arduino.
Ethernet cable is about 4 - 5mm ( ~1/5") in diameter and remember, it's much easier to pull it down your conduit than to pull it up. You've got gravity to help you that way. :slight_smile: Pull slowly so as not to damage the other cables (through friction) already in the conduit.
If the conduit is plastic, and not metal, tie a small iron object (like a very small bolt) to a cotton thread and drop it down your conduit. If it gets stuck you can 'jiggle' it with a magnet to free it or even draw it along a horizontal length of conduit. When your thread appears at the bottom, tie some thin string to the top and pull that through. Now you can attach your cable to the string at the top and pull it through. With metal trunking, tie a small piece of cotton wool to your thread and, if you've got a compressor, blow it through. Either way, it's a job that requires two people and much patience!

Henry_Best:
Now you can attach your cable to the string at the top and pull it through.

And make sure to pull another string through in parallel with the new cable so that, when you are finished there is a string that can be used to pull a future cable through without all the fiddling.

...R

Robin2:
And make sure to pull another string through in parallel with the new cable so that, when you are finished there is a string that can be used to pull a future cable through without all the fiddling.

Obvious thing to do, but sometimes forgotten.

Could you use WiFi? I ask the basic question back: Do you need it to be reliable - or not?

There are many ways to skin this cat, but first one must identify each sensor type and will it have its own uC? Or, will a uC (Arduino) manage multiple sensors. While this soundselementary, it plays into how you will multiplex or "post" sensor data. You can use Ethernet over cable to post to a webserver on the bridge or use a non-web protocol to aggregate the data below deck and just do an uplink over serial to the bridge, storing the received datagram in local Arduino memory (a data structure.)

I would likely opt for a non-web design initially and then maybe evolve the final, final design to a web front-end. Reason is that you are contemplating Statusboard for initial deployment. So, you want to make sure below deck work is ONLY done once.

Ray

Paul__B:

Robin2:
And make sure to pull another string through in parallel with the new cable so that, when you are finished there is a string that can be used to pull a future cable through without all the fiddling.

Obvious thing to do, but sometimes forgotten.

Yes it is obvious and yes I did forget it. :blush: