In the course Basics of Mechatronics we learned how to use and program the National Instruments myRIO microcontroller in the LabView software environment. We used many sensors, peripherals and motor control with the help of pulse width modulation, but we never touched or mentioned communication protocols. The main topic of this thesis are various communication protocols (SPI, I2C) enabled by the microcontroller in question and the resulting peripheral control (stepping servomotors). The emphasis is on upgrading existing knowledge with the help of an application that we can see in everyday life. That is a light source tracker or more commonly known as solar tracker.
I decided to make the tracker with the help of four light sensors and two stepper servomotors, which enable the platform to move in two directions (up-down and left-right, also known as pan and tilt). I used pulse width modulation to control and move the stepper servomotors and the SPI protocol to communicate with the sensors.
Initially I planned to make the platform out of plastic with the help of 3-D printer, but I ended up making it out of cardboard and rigid foam. The challenge was to ensure relatively accurate tracking of the light source, which I solved by using an upright cube mounted in the center of the four light sensors, which creates a shadow when the platform is not perpendicular to the light (sun). A shadow over the sensor means that the platform needs to move. A practical field test in sunlight (and indoors with a flashlight) was successful and the intended tracking accuracy was achieved. The tracker in question can then be used in a completely practical and currently very relevant application, namely as a sun tracker for photovoltaic panels that produce electrical energy. The more these panels are aligned with the sun, the more electrical energy they produce and, as a result, their efficiency is greatly increased.
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