Solar Tracker

This is a solar tracker that I’m working on. It’s a stationary robot that will keep a pair of solar panels perpendicular with the sun so that they can charge batteries. I only have one panel on it, but in the end, there will be two. By the time I was able to test it, it was already dark so I walked around with a high powered halogen lamp in order to simulate the sun and have the robot track me. I still have a bit of testing to do, but for the most part, it works.

Tracks the sun and moves a solar panel

  • Actuators / output devices: 2X Tamiya Wormgears
  • Control method: autonomous
  • CPU: Picaxe 40X
  • Power source: 12V Battery
  • Sensors / input devices: Photoresistors
  • Target environment: Outdoors

This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/solar-tracker

that’s really neat, could

that’s really neat, could you make a more in-depth description? I’d love to make something like this, but I’m not that good with electronics.

how is you charging circuit designed?

how are your photoresistors set up?

does it measure the max current it gets from the solar panel to center it?

 

Is it actually a "solar
Is it actually a “solar tracker” (sun) or just a photovore?

Sure, I’ll be updating it

Sure, I’ll be updating it with more information soon. But to answer your specific questions…

1.) Right now, it is a “dumb” charger. Meaning, that the solar panels will simply be hooked up in parallel with the batteries. I will however, eventually hook up a peak power tracker, and then a smart charger to it in order to maximize the amount of power I get from the sun.

2.) If you look closely at the picture, I you can see that the sensor has four photoresistors set up in pairs. There is also a pyramid looking thing that divides all of them. If the sun casts a shadow on one of the photoresistors, the tracker simply tries to fix it so that there is no shadow.

3.) I don’t measure max current from the solar panel, I use the sensor described in 2. I do however, measure currents, voltages, etc, using a data acquisition module, and a program called LabView.

Gabe

Well, it can probably be

Well, it can probably be fooled into tracking a source of light that is not the sun. (Kind of like what I did in the video) The sensor simply checks all four photo resistors and tries to balance the amount of light hitting each one. But when I made it, I assumed that the sun would be the brightest source of light out there, and would be the only source of light casting shadows on the sensors.

Gabe

Focus

Do you suppose this could be modified with a parabolic reflector in order that it would always focus the sun’s light onto a fixed point? I have a plan (Heh heh heh.)

That sounds like a cool

That sounds like a cool idea. Maybe use a newtonian telescope configuration like this one: http://upload.wikimedia.org/wikipedia/en/e/e0/Newtonian.PNG

Gabe

Dishes…

I was thinking of silvering a satellite dish. A bit of aluminium foil ought to di the trick. I happen to have one going spare. The way I understand this reflector is that it assumes radio waves are coming directly onto it in parallel and focuses them to a point (normally an LNB).

Wouldn’t that be, like, many hundreds of degrees celcius?

Not with Al foil

Doncha watch MythBusters? :wink:

I think they (or others, i forgot) had better luck with ordinary glass mirrors cut in many tiles. Or Mylar. Or polished metal sheet (silver, brass). Or packaging material for crisps (I think Americans call those Aluminum chips :wink:

Rik

Yes, I would think that the

Yes, I would think that the temperature would get pretty hot. I think the mythbusters episode was a bigger version. Didn’t they want to focus all that light to make a boat in the water burn or something? I believe that a smaller version works. Those solar ovens are based on the same principle. But yeah, now that I think about it, it probably wouldn’t be good to focus the light on the panels if they get that hot.

Gabe