Rainfall seriously over reported

OK, so first the obvious problem. As stated, serious overestimation of rain.

Just to illustrate take a look at August 14th on my Rain graph:

https://smartweather.weatherflow.com/share/4199/graph/10941/rain/4

Then look at August 14th on the local weather station:

http://www.bom.gov.au/climate/dwo/201808/html/IDCJDW7021.201808.shtml

The weather station measured no rain and the Sky, well as much as 2m (yes meters!) of rain in an hour. Hmmmm.

Go figure. Now I know that it’s a haptic sensor, and I know that I have a scheduled check for and fix of any loose bits and sources of vibration. Got that. Even went up recently and did half that and decided it needed a fix. For context here is the station:

https://community.weatherflow.com/t/photos-of-sky-and-installation/132/193

Basically there’s a TV aerial (A), and I slid an aluminum post over the top of it taller than the aerial by about 300mm (B). Snuggly inside that is another aluminum post, that is about 600m long ©, that sits snuggly on top of the aerial and finally there’s a 3m length (D) snuggly around that and atop that is the Sky.

To be clear B is a little loose on A, so at base has two orthogonally situated clap screws through it holding it tight and no wobble. At the top because the aerial is attached to the top of the aerial pole (A) with a U-bolt, that’s now around B and A. B has two vertical slots cut into it so it compresses tight and snug on A.

That junction between B and A at the top of A, has a wobble in it I found. I have to tighten the U bolt and/or dismount and cut another slot so that aluminum post (B) can close tightly around the aerial post (A).

The whole rig is tall and aluminum so sways in the wind (has no guy wires) but it is aluminum tubing form an old aerial structure and I am indeed still waiting for the strongest gusts of the year to see if it survives well without bending. If I trust Sky the peak gusts since installation have been around 80 kph (on Aug 15, surprise surprise around the day of that extreme rain measure above though the max win gust agrees well with local weather station that recorded a peak of 85 kph that day, certainly within microclimate tolerance).

All that aside, I know that on my list is to remove that wobble from the A-B connection at top of A.

BUT, my real question is this: Clearly if there’s a wobble or vibration in that joint that is travelling back up the post to the sky and tricking the haptic sensor into thinking raindrops be falling I’d be interested in the salient question of … wait for it … calibration. I’m curious what kind of signal is counted as a drop and how (actually as an engineer with a background in signal processing I’d be curious how it worked full stop, imagining a running time series correlation against a typical raindrop signal, though the different sizes of drop and angles would provide a family of candidate signatures methinks and my experience and recollection runs a bit dry). But I am curious what the haptic tract looks like and would love to see a graph of that, annotated with detected drops as a kind of insight into Sky’s innards.

So my question is in a sense, if nay such thing is possible in the field, or if you (devs) would agree that some kind of drill down into this data might have appeal and use to a sector of your market?

Not least because often the human eye remains a good deal better at interpreting such signals and differentiating signal from noise, and it would be nice to see clear noise. In a case like this as a before/after look at the sensor readings, before and after I fix this observed vibration between the poles.

Because I remain concerned that once that’s fixed, that there is still an issue present. We shall see.

6 posts were merged into an existing topic: Rain Gauge Reading - Wrong (auto-calibration system not yet deployed)