Here is my third heliostat prototype. Believe it or not, this one actually worked! Finally! Woo Hoo!
Here is a 8.5 hour time lapse video of its first run.
You can see that it does drift to the right slightly as the day goes on, but that really isn’t a big deal. I just had to adjust the settings in the Sun-Tracker program to fix it.
I’m not going to go into too much depth here because I am going to write some more in depth heliostat building tutorials in the future (Or maybe I already have. Check under heliostat projects).
At this point in time, I have already scrapped this heliostat for parts because I needed the stepper motors for my heliostat array project.
I do have a few pictures that I can show you though.
In the picture below, you can see how the threaded rods are set up to move the mirror. This was much easier to do than it was with the worm gears I was working with in the previous prototypes.
You can also see that the mirror is able to tilt either backwards or forwards through the use of a couple of door hinges.
Additionally, one problem I had was that water would get in to the soda container protecting the altitude stepper motor when it rained. This was easily fixed by switching it around so that the stepper motor was on top of the mirror.
In this picture, you can see how the mirror is set up to rotate along the azimuth. I used an old lawn mower tire rim to give the heliostat something to turn on. This was a pain to get level, but it was what I had on hand at the time. I have since switched to using lazy Susan bearings.
The stepper motors never seemed to have much trouble moving the weight of the mirror. Even if there was a problem though, it would have been easy to correct simply by using a counter balance.