Single Axis Solar Tracker

Our client for a team design course at Fort Lewis College requested a single axis, passive, solar tracking system that operated on a stand-alone power system. I designed the mechanical and electrical systems:

The prototype electrical control was provided by an ATTiny85 microcontroller, coupled with an off-the-shelf bi-directional H-bridge IC. A novel power supply design accounted for both inductive loads from the driven motor, and voltage variation from PV arrays. Firmware was developed in Arduino, using additional hardware plug-ins to port the software for the ATTiny family.

Mechanical design was performed using Autodesk Inventor. A robust but inexpensive 12-volt gear motor was coupled directly to the center mount which held the PV arrays. This simple system provided high torque actuation with very low power dissipation.

Data acquisition for design validation was implemented using low current Hall Effect sensors and simple voltage measurement. An Arduino performed filtering, processing, and data logging to an SD Card.

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