3d printable means that parts are never out of stock and upgrades are relatively straight-forward to implement (assuming you have the cad/STEP files. modifying STL/Mesh files is a pain in the ass)
Agree, though; for not that much $, you can get a pretty nice kit from Ali Express that'll spit out measurements over a serial port for use with APRS / LoRA or even just an arduino / raspbery pi ... etc.
During COVID lockdown I learnt 3D modelling via Blender and so STLs are my lifeblood for 3D printing!
After that experience, I replaced it with a Davis Instruments Vantage Vue, which has been running for 10 years without a single issue. Just needs periodic cleaning and battery replacements. Someone also made a device that goes inside the console to provide local access to the weather station (for Home Assistant integration, for example). It's called WifiLogger2. Pricy, but recommended if you want to pull the data from the console easily. I've also set up two more of these weather stations for family, and they've been similarly stable. So my experience with Ambient Weather left a bad taste. I'd rather pay the higher cost for Davis Instruments hardware that I know will work for a long time, than roll the dice with Ambient Weather ever again.
It's also telling that a search for "davis instruments weather station" on Amazon suggests the WS-2902, followed by actual Davis Instruments products. I imagine Ambient Weather is spending a lot of money for that search placement.
https://www.davisinstruments.com/products/vantage-vue-wirele...
Looks really nice! Thank you for the suggestion
Honestly, if you're in town, you're probably within radio range of someone else's station already for free.
Therefore for comparable, calibrated data for real meteorological use, there are standards (unfortunately national, so there might be differences in some places) for all the above. The sensor housing has to be white, provide shade and total rain protection, but well-ventilated by grills on all sides. It has to be mounted above a patch of lawn of at least 10x10m, no shade, no significant nearby wind barriers, at a height of 1.2m. All sensors have to be at least 10cm from the internal walls of the housing.
If you don't care about strictly calibrated scientific data to use in your weather model, of course a simpler device will do. Also, nowadays, it is possible to account for deviations of certain stations due to the aforementioned factors.
Another factor is also serviceability. A cramped tiny housing that is hard to open and inspect isn't ideal when you have people touring the country servicing weather stations all year.
It would be interesting if they could get some input from some industry experts to cost reduce and simplify for a few iterations. From a quick look at the files this appears to be what I’d expect from the dev board proof of concept stage of a project, before it was iterated on to be simplified for wider use. Hopefully they can get some time to do a few more cycles
Speaking from my experience.. the actual plastic body of the equipment is the easiest and most irrelevant part. You can 3D print it.. or even just get a bottle and cut it in half? The actual tipping bucket is also kind of ridiculous to make from scratch. There are plastic ones that are injection molded and made for pennies in China. (you'd probably need to contact the manufacturer and make an order of >1K of them). Much more interesting would be a system for calibrating them (hat's not as labor intensive as what they present
Real concerns that need solutions are going to sounds ridiculous but are actually really challenging:
- Moisture will penetrate any enclosure and fry your electronics relatively quickly if you're in the tropics. It's very very challenging to seal things completely. All sealing solutions degrade over time
- People will steal the solar panel within 48 hours. The reality is that nothing about this station needs more than a coin cell (depends a bit on how often you measure the anemometer I guess). Power solutions are not easy or cheap. Weird power issues and making your logging equipment resilient to that is hard
- Most plastics are not happy in direct sunlight. We tried some small 3D printed parts. They all "melted" and fell apart quite quickly (I'm sure some alternate 3D printing material would hold up better)
- A bird takes a massive shit in your rain gauge, what now?
- cockroach crawls into your tipping bucket mechanism and dies. what now?
- Electronics? You know loves electronics? Ants! You're gunna have a nest in all that void space
- free standing plastic enclosures. You will likely have a wasp nest within 6 months
- Exposed cables? Rats will chew through them. Plastic box? Rats will chew through them. Metal box? It'll rust through in 4 months. Where I've tested the largest animal we had to deal with were monitor lizards. I imagine in Africa you have larger animals...
Making an actual low power logger? Surprisingly challenging. The ones you can buy online are 100 USD minimum and use shitty proprietary cables/software. Have terrible power performance and aren't very waterproof
For a more serious look at this space, I'd look here:
https://thecavepearlproject.org/
Also, the most popular rain gauge manufacturer has shifted to tipping buckets to a tipping spoon design.
https://www.davisinstruments.com/products/rain-collector-tip...
I have no special insight in to why. I've look at the internals of both designs and the new mechanism is more complicated (has more component parts). But they no longer sell the tipping bucket design, so I'm guessing there is good reason they did that and there is some advantage (maybe in terms of calibration?)
Yes, tipping buckets are less exact than tipping spoons, especially in low-rain season. The bucket is never perfectly symmetrical and the mounting is never perfectly level, so one side of the bucket will hold more water than the other before tipping, leading to asymmetric tips.
The two bucket design doesn't seem overly problematic though. Often you can see this in the record as time-to-tick will follow a sawtooth pattern. I haven't tried it myself, but .. assuming you don't have any skips in your record.. I imagine you could periodically use a long syringe and measure the exact volume that triggers a tick on each side. And then correct the record in software.
A bit of a tangent.. but I've also not found any software or algorithm for correct interpolation of rain volume. Maybe you know of something? ChatGPT suggests a few things :)) but I wonder if there is some standard method people use
Calibration will also be drifting off for dirt accumulation and evaporation. Different fill states of each bucket lead to different evaporation in each bucket (smaller will evaporate faster, deviating towards even smaller amounts), and different resting times lead to more dust and algae settling in the bigger bucket, making it even heavier.