From a roller coaster to a fun house, and even an electric guitar, here are 10 projects designed by kids who took the LED challenge.
Over the past few years, we here at EE Times have joined up with Digi-Key and Microchip on a series of student design challenges. Our intent was to inspire middle and high school students to learn about electronics and how to use a microcontroller to control colorful light-emitting diodes. Truth be told, we were unexpectedly inspired by the hard-working teachers and parents (some of whom were just learning about electronics themselves) who led the initiatives at their schools.
Hopefully, some of these great mentors will have changed the course of education for some students.
In fact, whether they were entry-level or more advanced, students described the great learning experience they had. As one fifth grader noted on the entry form: "During the LED club I have learned a lot about lights and electricity. Before I didn't know that you had to have a way for the electricity to go in and out. I learned about resisters that slow down the flow of electricity. I also learned that the bigger the resister, the more it slows down the flow of electricity. I learned how to make an LED light up. I learned that LED stands for light emitting diode, not little electrical device."
Competing teams -- ranging from fifth to twelfth graders -- received a free materials kit containing all the electronic parts needed for a project (although some chose to augment the BOM.) At the conclusion of the contest, each team had to submit a description and photos of their project, circuit schematics, code, additional drawings and photos showing their progress, and an optional video of the entry in action.
Here, we present a compilation of some of the incredible ways that students incorporated LEDs into a design -- from a roller coaster to a fun house, and even an electric guitar.
Click on the schematic to start the slideshow.
LED Christmas Tree and Star
LED Christmas Tree and Star: The LED Christmas Tree and Star project designed by The Spectacular Seven, a team of students from Oak Canyon Junior High in Lindon, Utah, won first place in the EE Times/IGEN Community Pride LED Contest. It features a small tree made from PVC piping, festooned with flashing LEDs on the branches and a star on the top, with a 7-segment display counting down to the New Year. The project uses not one but two microcontrollers, one each for the tree and the star.
Student notes: When we started this project as a group of friends, we had no idea how challenging it would be. We didn’t even know what 'LED' stood for. Now we know all about light-emitting diodes, resistors, the difference between NPN and PNP transistors, and much more. We learned how to measure voltage, program lights, solder, and how to use quality control. No one in our group really could have pulled this off on their own. It took a lot of "boring" videos, whiteboard diagrams, and lots of notes to scratch the surface of understanding the LEDs.
We wanted to control all of the LEDs individually from the microcontroller so that we could do some fun light patterns. After counting the LEDs (32 of them) we found that we did not have enough control lines from the microcontroller. We discussed ideas and learned about a way to multiplex. Each of the eight branch levels would be tied to eight transistors on one side and each of the four sides of the tree would be tied to four more transistors. We also learned about persistence of vision that helped us to have more than one LED appear to be on at a time.
The programming of the lights was the most challenging part of the project. Only a little part of the programming system is tangible. From going from our heads to the lights on the tree, there are many steps to take. First, identify every light. In order to know which light is which, every one needs a name. Second, create a sequence. A sequence is a binary code that turns certain lights on (1) or off (0). Third, type the sequence patterns into the computer.