Starting to build a sun tracker - or how to find North

A project log for SunTracker 2 Revision 3

A learning platform for optimizing solar systems energy output through alignment to our suns path across the sky.

FrankFrank 08/03/2019 at 03:230 Comments

The first steps on the solar tracking project were taken in April, when I was reading about building a digital compass. There are various project descriptions on the net, and I was interested what sensor is best suited for that task. Based on what I can source locally, I zeroed in on modules with the LSM303 chip, made by ST Microelectronics. Below shows the first breadboarding tests with the MM-TXS505 module from Sunhayato.

The MMTXS505 modules uses the LSM303D chip released in 2012. It is quite stable, and offers the ability to select one of two possible I2C addresses. I noticed that later chip revisions (e.g. LSM303DLHC) only hardcode one address, which prevents using more than one sensor on a single I2C bus. Now that I can determine North, I can plan for adding the modules that would add the sun position information and provide the tracking output.