Abstract

Have you ever seen clothing with built-in lights? This might sound like something out of a science-fiction movie, but electronic textiles (>e-textiles for short, also called wearable electronics or sewable circuits) really exist. Instead of using hard surfaces for circuits (like what goes inside your computer or cell phone), e-textiles weave electrical parts like batteries, wires, and lights directly into clothing that you can wear to make the clothing do fun, interesting things like light up, respond to sound, or even serve medical purposes (like a shirt that monitors heart rate and breathing patterns). In this science project, you will build a light-up "dance glove" that you can use to put on your very own light show!

Objective

Design and build an LED glove.

Introduction

Clothing that lights up might sound like something out of a science-fiction movie, but electronic textiles (or e-textiles for short), are actually used in the real world for both decorative and practical purposes. Clothing with built-in lights (also called "wearable electronics") can be used in light shows and artistic or dance performances. For example, all of the photos in Figure 1 were taken in a dark room by waving a glove with built-in lights in front of a camera. Since the room is so dark, the camera takes a longer time to take the picture, letting in more light; this lets you "draw" shapes in midair using the glove! While the pictures in Figure 1 are pretty amateur, there is actually an International Gloving Championship, a competition where people "dance" using their hands with LED gloves. Do you think you can make gloves that are good enough to win a competition?

Once you build your own LED dance glove, you can take pictures like the ones in Figure 1, make movies, and show them off to your friends. This science project will teach you how; but first, you will need to learn a little bit about electrical circuits.

Electricity is what powers many of the devices that we use every day, like computers, TVs, lights, and phones. You can read more about electricity in the Science Buddies Electricity, Magnetism, & Electromagnetism Tutorial. Materials that let electricity flow easily are called conductors. Conductors are usually metals like copper, aluminum, or steel. Materials that prevent electricity from flowing are called insulators. There are many types of insulators, including most rubbers and plastics. Conductors, insulators, and other special components that you will learn about later are combined to make up electrical circuits, which allow electricity to flow through these components in a careful, controlled way, usually to power something like a light or a motor, or to do calculations inside a computer. Most electronic devices that you use every day have specialized circuits inside them. In this science project, you will build your own circuit to light up a glove that you can wear.

The circuit you will build in this science project can be represented by a circuit diagram. Circuit diagrams are the "language" that engineers and electricians use to represent physical circuits with drawings. They use symbols to represent physical objects. Figure 2 shows three different representations of the same simple example circuit: a photograph, a computer drawing, and a circuit diagram.

There are three circuit components shown in the circuit diagrams in Figure 1:

• Battery: The power supply for your circuit. Batteries have a positive terminal marked with a "+" sign, and a negative terminal (the symbol for negative is "-", but this is usually not marked on the battery).
• Light-emitting diodes (or LEDs for short): The lights in your circuit. LEDs have two wires sticking out of them, called leads (pronounced "leeds"), one positive and one negative. LEDs are like one-way valves for electricity; they only work when electricity flows through them in one direction.
• Resistors: Circuit components that resist the flow of electricity. They are important to use because they decrease the total amount of electricity flowing through a circuit, which is important because too much electricity flowing through an LED can cause it to burn out or break. Resistors also have two leads sticking out of them, but electricity can flow through them in either direction.

The circuit you will build in this science project is slightly more complicated than the one shown in Figure 1. To continue, you will need to understand a few more concepts: open and closed circuits, and series and parallel circuits.

In a closed circuit, there is a complete conductive path through which electricity can flow. In a simple circuit with an LED or lightbulb and a battery, this means that the lightbulb will light up. In an open circuit, the conductive path is broken somehow; for example, by a disconnected wire. This prevents electricity from flowing, so the lightbulb will not light up. A switch can be used to control whether a circuit is open or closed, allowing you to perform functions like turning lights on and off. Figure 3 shows simple open and closed circuits.

What if you want to hook up more than one light to a battery, like putting multiple LEDs onto a dance glove? There are two primary ways to do this: in series and in parallel. In a series circuit, all of the lights are connected to the battery in a single "loop," which means the electricity must flow through each light in order. In a parallel circuit, there are multiple "loops," so the current "splits up" and flows through each light individually. Figure 4 shows diagrams of series and parallel circuits. When using lightbulbs or LEDs, it is better to attach them in parallel; that way, even if one light goes out, the rest of them will stay on. So when you design your LED glove, it will be important to connect all your LEDs in parallel.

So, now that you have a basic understanding of circuits, let us show you how to apply it when you build the LED dance glove. In this electronics science project, your goal is to build a wearable glove with a battery, multiple built-in LEDs, and an on/off switch. Figure 5 shows a circuit diagram for the circuit you will build.

And last but not least, in this science project you won't be designing a circuit that will go inside an electronic device like a computer; your circuit will go on a piece of clothing that you will wear! This means your design must be ergonomic. Ergonomics is the study of how devices and products comfortably fit the human body. For example, office chairs must be comfortable and ergonomic for people who sit in them for 8 hours a day. Consumer electronic devices like cell phones, MP3 players, and video game controllers must be ergonomic and fit easily into the human hand. As another example, can you see the design differences in three successive generations of Nintendo® video game controllers in Figure 6?

Can you think of more examples of everyday products that were designed to be ergonomic? Use what you've learned to start thinking of important design criteria for your LED dance glove that involve ergonomics. Luckily, some products have already been designed with e-textiles in mind. For example, the LEDs and batteries in this science project were designed to be sewn directly into fabric, and you will use conductive thread instead of copper wires. This will make the job of designing an ergonomic glove a little easier. For a preview about the process of building the LED glove, watch this video before you move on to the Procedure section:

Terms and Concepts

• Electronic textiles or e-textiles
• Electricity
• Conductor
• Insulator
• Circuit
• Circuit diagram
• Symbol
• Battery
• Light-emitting diode or LED
• Resistor
• Closed circuit
• Open circuit
• Switch
• Series
• Parallel
• Ergonomic

Questions

• What is a circuit diagram, and how do its symbols represent real-world circuit components?
• Why is it important to also use a resistor when hooking up an LED to a battery?
• What is the difference between an open and a closed circuit? How can a switch be used to control whether a circuit is open or closed?
• Is it better to connect multiple LEDs in series or in parallel?

Materials and Equipment

Many of the supplies needed for this science project can be ordered from SparkFun Electronics.

• LilyPad LEDs (1 pack of 5); available from SparkFun Electronics in various colors. Note that these LEDs contain built-in resistors, so you do not need to purchase resistors separately.
• LilyPad coin-cell battery holder with built-in switch; available from SparkFun Electronics
  • Alternatively, you can purchase a coin-cell battery holder and a power switch separately, but this will be more expensive.
• CR2032 coin-cell battery; available from SparkFun Electronics
• Sewing needle. A needle set is available from SparkFun Electronics or at local arts and crafts stores.
• Conductive thread (1 spool); available from SparkFun Electronics

You will also need to gather:

• Lab notebook
• Lightweight gardening or winter glove. We recommend using a fabric that can be sewn to easily, e.g. do not use heavy leather work gloves or thick, insulated winter gloves.
• Sewing thread (1 spool), color of your choice; available at local arts and crafts stores
• Fabric paint, color of your choice; available at local arts and crafts stores
• Optional: Digital camera to take pictures/videos of your LED dance glove performance.
• Someone who has experience with basic sewing

Experimental Procedure

Variations

Careers

If you like this project, you might enjoy exploring these related careers:

Related Links

• Science Fair Project Guide
• Other Ideas Like This
• Electricity & Electronics Project Ideas
• Technology of Art Project Ideas
• My Favorites

Cite This Page

General citation information is provided here. Be sure to check the formatting, including capitalization, for the method you are using and update your citation, as needed.

MLA Style

APA Style