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Topic: solar tracker using RTC (Read 5 times) previous topic - next topic

AWOL

I just compiled it for a Linux box for speed of testing and simplified I/O, so the size is irrelevant, I'm afraid (FWIW it's a 36kB executable on a Xeon W3530).
Accuracy should be maintained for an Arduino, though.
At the moment, I don't have the time to go through and move the tables to PROGMEM for AVR, but I'm pretty certain it would work as-is on a Due (64 bit doubles - yay!)
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

Nick_Pyner


whole idea is i wanna do with cheaper solution , I wanna use only rtc, linear actuator  and arduino board  for the project.
If i am using above component is it possible to it??
if yes how can i do it??
how can calculate sun elevation angle??
i don't have any sensor to locate and control the position.



Obviously, it is possible to do it, but it isn't advisable. What you are talking about is altitude but, if you are only going to control one axis, you will be better off putting the device on an equatorial mount and controlling the azimuth. I have already told you where the calculations are but, when I said what I said about a lookup table, I didn't realise it would be so compact, and I think you would be better off trawling for an on-line service, or a freebie programme that can provide the data for same, thereby saving you from calculating anything.

AWOL

Update:
The SPA source compiles for the Due (64 bit doubles) and produces correct results.
The size of the main tables comes to 17532 bytes, so even halved for 32 bit floats won't fit in RAM on a Mega.
It compiles, but doesn't run (see above), on a Mega, with a sketch size of 29K, so I'd be surprised if it squeezed into a Uno, even with the tables in ROM.
A challenge.
I'm on it.   :)
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

PeterH

How accurately are we trying to track the sun's position? Some of the solutions being discussed seem to be aimed at very high accuracy indeed - which might be justified if we're trying to aim a telescope but would be ridiculously over the top if we're just trying to point a solar panel in the right general direction.
I only provide help via the forum - please do not contact me for private consultancy.

Nick_Pyner


How accurately are we trying to track the sun's position? Some of the solutions being discussed seem to be aimed at very high accuracy indeed - which might be justified if we're trying to aim a telescope but would be ridiculously over the top if we're just trying to point a solar panel in the right general direction.


Indeed, and so absurdly so that a lust for intellectual exercise by the ignorant is the only explanation. At  this 1x magnification, an astronomer would be seeing it as so trivial it is a potential use for that old iron frame falling weight siderial clock gathering dust in the attic.  The Arduino/RTC/linear actuator could then be used just to lift the weight at midnight. No calculations needed - probably.   

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