Chris just shared a new tutorial: "Pycom LoPy Overview"
The two main standards at work in the low-power long-range radio game are LoRa and Sigfox. I discussed Sigfox in the Pycom SiPy Overview so I won’t do that again here. The Pycom LoPy is the device that adds LoRa technology to the basic features seen …
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How can I change my Lopy4 to work on 433Mhz
Hi Joaquin,
You just set the frequency when you initialize the radio in the code.
Be sure to connect an antenna to the board before transmitting or it will damage the board!
I’m thinking about using LoPy 4 for a fleet of about 6 USVs. Although Ardupilot running on a dedicated FC might be the obvious choice, I have an open source marine autopilot that is suitable for the very limited requirements of our system. That could run on the ESP32 component of the LoPy4. The comms requirements are rather greater than typical IoT, but not really very much. From controller to USV, data flow will just be occasional positions (perhaps a sequence of way points to define a course - but usually only 1). Data flow in the opposite direction will be monitoring battery SoC and position. Frequency from USV to base could be as low as once per minute and from base to USV would be perhaps 10 positions over the course of several hours.
Range will typically be 2km with the possibility of having the base station set at some height, perhaps 5m, and the USV LoRa modules (and antennae) at a height of order 1m above the water.
Is LoPy4 likely to be suitable?
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Hey Trevor,
Welcome!!
Sounds awesome. It should (I’ve heard LoRa doesn’t work great over large bodies of water) work as long as you have line of sight and keep the antenna roughly pointed towards your base station/use an omni directional antenna.
You’ll have to bake in some level of signal reliability, such as a heartbeat signal, and make use of Ardu pilots return to home.
I’m keen to see how you go!
PS: if you have some photos of the USVs I’d love to see them.
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Line of sight should be good. I was looking at a standard antenna (CE04928). Do you recommend something else? Directional could be made to work but would make things more complicated - omni-directional would be a lot easier.
Advice re heartbeat and RTH noted.
Vessels not constructed yet. Earlier version that is working was short range for RC sailing - examples here: https://www.facebook.com/search/top?q=buoybot . Next version is for open water - ie USVs are to be semi-autonomous rounding marks for dinghy/catamaran/kite foil racing. Hence need for longer radio range so considering LoRa.
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