Solar Cell Tracking

thingiverse

**Affordable Solar Cell Tracking Project** I recently purchased a couple of small solar cell modules on eBay for under $10, and they work perfectly. It's time to take it to the next level with some tracking. The 3D printed parts are simple and straightforward, so I thought I'd share them with you. I haven't written the code yet, but I'll probably use an Arduino module as I have plenty of experience with them (code added). To track the sun, I don't rely on LDRs; instead, I measure the solar cell's voltage and adjust its position accordingly. It's not rocket science – just simple measurements. **Electronics Enclosure** The test enclosure is designed to hold one or two PCBs and up to two 18650 batteries. The top is secured with four screws, and there are cut-outs for the Solar Cell cable, horizontal servo cables, and a circular on/off button. The wall thickness is 3mm. **Parts Suppliers/Cost** Solar Cell: €2.80 (available at Banggood) Charger Module: €1.10 (available at eBay) Micro Servo: €2.26 (available at eBay) Servo Test Unit: €1.50 (available at eBay) The total cost for the electronics should be around €6, not including the Arduino Pro/Mini. Any microcontroller can be used, and the code is simple to port. **Servos** I purchased low-cost servos and decided to test them using an inexpensive servo tester from eBay. The servos worked perfectly and can handle the weight of the printed parts and solar cell chosen. To extend the rotation of any analogue servo, you can add a couple of resistors to the feedback potentiometer. However, this was not necessary in my case, as I achieved ~180° rotation with the Arduino and servo example code. **Code Update** I wrote some code to manually test the design using two servos, a couple of 10K pots, an Arduino Uno, and a few lines of code. It works a treat! **Updates** * Removed the original small enclosure as it was not adequate. * Added a second Solar Cell Housing with a center support section for attaching battery cables to prevent wear at solder joints. * Added cable-tie clip prints to attach battery and servo cables to prevent fraying or breaking from their solder points. * Updated the tracker code to update every three minutes (tracker1.05.ino.txt). * Added an image of the full-sized version using MG09R Servos.