Students

Andrew LeRoux
Economics, 2020

Project Description

This project is a 10×10 matrix of RGB LED lights, each individually controllable through the use of an Arduino board. Each LED light is part of a LED strip. These LED strips are flexible circuit boards that have LED’s imbedded within the circuit board. The LED’s are RGB (red, green, blue) and have a variety of color combinations that are possible. Each strip has 10 LED’s in it, and each strip is laid out side by side and connected through the use of wires. All of the LED’s are then connected to an Arduino board that had preloaded code that is used to control each individual light. The LED’s and the Arduino are powered through the use of a 12 volt power source that is connected to the Arduino. The frame of the board is made out of wood with a glass panel in front. This glass panel has been coated with glass frosting spray in order to diffuse the light and give the display a more cohesive look.
The main purpose of this project is to display information through the use of a grid of lights. Almost any type of display is possible (within the constraints of a 10 by 10 grid), such a text displays, symbols, or light displays.

Technical Background

LED’s are light emitting diodes, which are semiconductors that emit light when an electric current passes through them. There is a wide variety of LED’s that can be used, many having different functionalities and forms. One variety is individually addressable LED strips. LED strips are essentially flexible circuit boards with built in LED lights than can be cut to adjust their length in order to achieve the correct amount of lights and strip size for your project. These strips can come in a single color or be RGB (red, green, blue) which gives them the ability to change colors. Single color LED’s emit one specific certain wavelength of light, while RGB LED’s are actually a combination of 3 LED’s in one, where each LED will emit red, green, or blue at varying intensities. The combination of these 3 emissions together will produced the desired color. Each color has 255 different output, achieved by varying the voltage given to each input power rail. Therefore by combining all three colors, there are more than 16 million different color combinations.
However, in order to use LED lights it is necessary to understand how basic circuits work. LED’s are a type of diode, which Is a semiconductor device that typically conducts current in one direction. LED’s needs to connected in a circuit in order to be functional. A circuit is a closed path in which electricity can flow through. In a circuit electricity flows through a material that is conductive, such as copper wire, and typically enter and exit at the same place (the power source). A very basic type of circuit could contain a power source such as a battery, an LED, and a resistor. The power source is used to supply power to the system, and the resistor is used in order to decrease the current. LED’s are connected in the circuit using the cathode and anode. In a simple circuit, current would flow from the power source, through the resistor, to the anode, through the LED, to the cathode and the back to the power source. The resistor is necessary since most power sources supply far more current than is necessary to power the LED, and the resistor reduces the current flow. If there is to much current supplied to the LED, the LED could burn out. It is important to wire a circuit properly since if the circuit is not fully connected, or one of the wires is crossed (in this example if the current was trying to flow into the cathode), the circuit may not work or it could short circuit.

Aasvik, Mads. “Programming Digital RGB LED Strips with Arduino and the FastLED Library.” Norwegian Creations, Norwegian Creations, 16 Jan. 2018, www.norwegiancreations.com/2018/01/programming-digital-rgb-led-strips-with-arduino-and-the-fastled-library/.

Buckley, Ian. “Ultimate Guide to Connecting LED Light Strips to Arduino.” MakeUseOf, MakeUseOf, 25 May 2017, www.makeuseof.com/tag/connect-led-light-strips-arduino/.

“LED Strip Lights: Everything You Need to Know.” Waveform Lighting, Waveform Lighting, 2019, www.waveformlighting.com/led-strip-lights.

“Lesson 2 – Resistors.” A Rough Guide to Electronics – Lesson 2, MadLab, 2010, www.madlab.org/electrnx/lesson2.html

Design Drawings

Fabrication Process

Final Result