Hello, I’m currently working on a project for our sailing club, and a friend pointed me towards meshtastic. I’m not really a DIY electronics person, but so far it looks like a close match; I thought I’d briefly outline our plans, and would be grateful for any feedback, especially whether meshtastic would be suitable for this.
We are racing dinghies on a small reservoir in the centre of Birmingham (UK). The idea is to equip each boat with a GPS tracker, to allow not only live-tracking for the purpose of running the race, but also for replays and post-mortem analysis (eg identifying where one boat is slower than another; this can be used for coaching purposes). The reservoir’s maximum dimensions are 800x550 metres.
There are commercial solutions, but they use SMS for data transmission, and are quite expensive. Our main feature is that we sail in a restricted area only, so SMS seems overkill. We have around 20 boats in a normal race, up to about 30 boats for bigger events. The maximum upper limit will probably be 40-50 boats. We have 7 marker buoys spread around the water which indicate the course; each of them would also have a tracker on it, so that we can check boats sail the proper course. They would also act as further mesh relays.
Each tracker would (after being switched on) regularly send its position to the mesh. A ‘base station’ on the shore receives the positions and stores them in a database for later processing (on a web server); at the same time the boats’ positions would be plotted on a screen. Each race lasts just over an hour, so power is not an issue. The trackers would need to be waterproofed, as boats do occasionally capsize (through they wouldn’t be underwater for very long, and not very deep). They would not need a screen, simply a couple of LEDs to indicate operating status. You switch them on, and they start broadcasting until you switch them off. Each device would have a unique id to link them to a boat. No pairing with phones would be required.
So my first question is whether meshtastic would be a good match for this. My feeling is that it would be ideal for this purpose, as we have a smallish number of units in close proximity, and only for a short duration at a time, and a very simple and small payload for each message.
Second, what would the transmission rate be? If each tracker sends out its position every n seconds, how low can n be without swamping the mesh?
Third, how accurate is the location information? It’s inner city, but under an open sky (except for the odd clouds). Would this typically be in the range of metres, or tens of centimetres? If we have a start line defined (with two marker buoys with trackers on), could we reliably identify if a tracker had crossed the line at a given time?
And finally, as I mentioned, I’m not really an electronics person (though I do have a soldering iron), so how easy would it be to assemble the units and use them in a race situation? The software side would not be an issue.
Thank you very much in advance,
Oliver