Solar Tracker
Its about how an Arduino based dual axis solar tracker was made.
In modern solar tracking systems, the solar panels are fixed on a structure that moves according to the position of the sun.
We designed a solar tracker using two servo motors, a light sensor consisting of four LDRs and Arduino UNO board. Four LDRs and Four 100KΩ resistors are connected in a voltage divider fashion and the output is given to 4 Analog input pins of Arduino.
Working
LDRs are used as the main light sensors. Two servo motors are fixed to the structure that holds the solar panel. The program for Arduino is uploaded to the microcontroller. The working of the project is as follows.
LDRs sense the amount of sunlight falling on them. Four LDRs are divided into top, bottom, left and right. For east — west tracking, the analog values from two top LDRs and two bottom LDRs are compared and if the top set of LDRs receive more light, the vertical servo will move in that direction.
If the bottom LDRs receive more light, the servo moves in that direction.
For angular deflection of the solar panel, the analog values from two left LDRs and two right LDRs are compared. If the left set of LDRs receive more light than the right set, the horizontal servo will move in that direction.
If the right set of LDRs receive more light, the servo moves in that direction.
Servo Motor SG-90
LDR (Light Dependent Resistor)
An LDR is a component that has a (variable) resistance that changes with the light intensity that falls upon it. This allows them to be used in light sensing circuits. Some uses are listed below.
Lighting switch
The most obvious application for an LDR is to automatically turn on a light at a certain light level. An example of this could be a street light or a garden light.
Camera shutter control
LDRs can be used to control the shutter speed on a camera. The LDR would be used to measure the light intensity which then adjusts the camera shutter speed to the appropriate level.
Jumper Wire
A jump wire (also known as jumper wire, or jumper) is an electrical wire, or group of them in a cable, with a connector or pin at each end (or sometimes without them — simply “tinned”), which is normally used to interconnect the components of a breadboard or other prototype or test circuit, internally or with other equipment or components, without soldering.
Individual jump wires are fitted by inserting their “end connectors” into the slots provided in a breadboard, the header connection of a circuit board, or a piece of test equipment.
Arduino Uno
The Arduino UNO is an open-source microcontroller board based on the microchip ATmega328P microcontroller and developed by Arduino.cc. The board is equipped with sets of digital and analog input/output (I/O) pins that may be interfaced to various expansion boards (shields) and other circuits.The board has 14 Digital pins, 6 Analog pins, and programmable with the Arduino IDE (Integrated Development Environment) via a type B USB cable.
So we did a lot of connections and for the making of the body we used metal strips and did soldering to complete the circuits.
There were a lot of issues and we had to rewire it many times. Finally it worked. Below are images of it at various angles of projecting light from a flash light.
The shadows make it clear that the solar tracker was moving in the direction of the incident light. The work was well implemented.
It was a team effort , teammates include my college classmates.
