wishlist for interfacing / new sensors

Hi,

Taking the first steps in getting my FK50 to work. After my short experience of a few hours playing with this unit, I would like to request for a few options (mostly software/firmware related).

First a few words about my ‘use-case’ : I have an autonomous observatory with relatively unreliable internet connectivity. As such, we need a weather monitoring setup which would be in direct communication with the computers controlling the observatory. The control computer monitor the weather condition and then depending on safety parameters open the dome and startup the telescope for a night of observations. Weather remains a continuous parameter to watch out for through the night.

With this in mind, here are a few ‘wishlist’ points:

  1. USB or other connectivity to obtain ‘real-time’ data independent of a mobile app.
  2. Additional sensors for light level and cloud cover. Is there a template for adding new sensors (software as well as for the pcb)?

Looking forward to hearing your take on the above points.
Thanks!
Shashi

Hi @shashikiran.ganesh !

Your first request has sparked a pretty lively conversation on our team about different ways we could approach getting data off the station without using the app. Since the station itself can serve as a wireless access point, we were wondering if having the computer directly “talking” to the station over its own WiFi would work as an alternative to the USB solution you propose?

Otherwise, we’re investigating what it would look to to develop the capacity for real-time USB data uploads (and someone else on my team may send a couple of exploratory questions your way) and whether that is something we might want to pursue.

As for adding light level and cloud cover to the weather module, those are both good suggestions–I wonder if other FieldKit Weather users might find that useful. @jbentley @dkastl @jtkerb @JoGoyes @nabba – what do you think?

Hi @lindsaystarke,

Thanks for the reply. Yes, talking to the station directly via its own WiFi would be a quicker route I guess. Once my laptop connects to the station’s AP, I am able to read the two lines via a browser at http://192.168.2.1/
So it should be relatively straightforward to have a url where the current weather parameters could be put down in a simple ascii format. Every new access to that url could provide the latest read values.
We may need to have some security mechanism to allow only a recognized computer to connect with the station’s AP.

Thanks for considering it!

Best wishes,
Shashi

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@lindsaystarke - if there is a solar panel, is there a way to measure power coming out of that / recharge rate as an index of cloud over?

That’s an interesting idea to use the recharge rate as a proxy for cloud cover. Will require some amount of calibration/modelling to see how the rate changes as a function of time of the day and with season. It won’t work at night.

In the past, I had used an MLX90614 chip as a cloud sensor - this is commonly used in the infrared non-contact thermometers. It works by sensing the temperature of the sky towards which it should be pointed. Something similar is used in commercial cloud sensors such as the Boltwood cloud sensor.

A TSL235R sensor is suitable as a light level detector. I had used these two sensors along with an SHT11 temperature sensor all interfaced with an Arduino using a custom shield.

@lindsaystarke could you please let me know what specification solar panel would work with the FK? I will try to source it locally.
Thanks!
Shashi

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Hi there @shashikiran.ganesh – the solar panels that we supply are 10W 12V panels (specs available here) so that would be a good place to start. The most important thing to note is that the power cable is terminated with a JST connector that will connect to the header on the lower board marked “SOLAR” (not the one marked “BATTERY”), so whatever panel you use will need to work with that setup. I hope that helps–please let me know if you have further questions!

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circuit solar panel voltage is actually measured by the system, though we don’t currently push that data out to the portal. That said, because it’s not open circuit and the demand on the panel varies, it’s not even a great proxy for insolation, and insolation isn’t a great proxy for cloud cover. A dedicated solution like measuring diffused sky temperature against ground temperature is probably much more appropriate.

Bradley