The panel is mounted to a frame, which is attached to two bike wheels. The wheels are mounted to a larger wooden frame, and the wheels and panel are moved by a 12 volt linear actuator. The sensor is an LED model and is purchased from Redrok Energy.
The LED sensor senses the path of the sun and tells the actuator how much to move to keep the panel properly oriented. At the front of the tracker are two legs that can be adjusted to the proper altitude for seasonal changes.
I used bicycle wheels because they are durable, strong enough to handle some weight, and best of all, in my case, free!
Step 1: What do you need?
*Several treated 2x4's (Lowes)
*Two wheels from a free bicycle- free or almost free bikes are pretty easy to find from the local landfill or thrift store
*A piece angle iron with pre-punched holes (Lowes)
*A 12 volt linear actuator-(~$75?)- (Ebay)
*An LED tracking sensor- (~$40)( http://www.redrok.com/led3xassm.htm#led3xforsale )
*Various nuts, bolts, screws, cable and wire -(scrounging around my workshop)
Step 2: Making the base, and mounting the wheels
I cut a couple of small pieces of angle iron with a hacksaw, found the mid point on the cross members, and attached them exterior woodscrews. I put the wheels through the holes, and spun them with satisfaction.
Here is a picture of the top wheel being mounted.
Step 3: Adding the wooden frame to the wheels
The 2 x 6 isn't wide enough to mount the panel to, so I added some smaller 2 x 4's to the top and bottom of the board, cut to the size of the panel. Each 2 x 4 board is as long as the solar panel is wide, and was attached to each end of the 2 x 6 with screws and bolts.
This allows a nice flat place on which to mount the panel. I attached small pieces of angle iron to the holes on the end of each panel, and then screwed them to the wooden frame. This secured the panel to the frame.
Step 4: Adding the linear actuator
I mounted it on the one side of the frame with a through bolt, and attached it to the movable solar panel frame. To mount it to the side of the frame holding the solar panel I just used a staple on the board that moves on the bicycle wheels. A short piece of cable goes through the hole on the linear actuator and the staple, and iIused a small cable clamp to secure it. This allows everything to move around and flex as needed when it's moving. When hooked to the battery the actuator moves the panel all the way to one side, and reversing it moves it all the way back.
The next step is giving the tracker the smarts to know when and how much to move.
Step 5: Adding the LED tracker
Go to http://www.redrok.com/led3xassm.htm#led3xforsale to purchase one if you want to try this yourself. There are plenty of pictures of how other folks have mounted them at http://www.redrok.com/electron.htm#led3x . I put mine in an empty peanut butter jar and mounted it to a 2 x 4. I attached the 2 x 4 to the side of the unit to get the LED tracker up above the panel to give it an unobstructed view of the sun.