Introduction to Rapid Prototyping and Physical Computing

This class provides an introduction to modern rapid prototyping techniques such as laser cutting, 3D printing, and microcontroller programming (such as the Arduino system). Using these tools, small multidisciplinary groups conduct the hardware project of their choice exploring topics as varied as: Universal Access, tangible interfaces, toys, personal or medical assistants and new musical instruments

INFO 4320: Welcome

In-class Projects

These are the three projects I have built throughout the semester.

RGB LED

I designed a jack in the box with two mickey mouses spin inside of it. The idea is to use a photoresistor to sense the light in the box. If the box is closed, with no light coming in, everything remains quiet. However, when the box is open, the lights come in. The lights trigger the photoresistor; therefore, the photoresistor receives the lights and triggers the stepper to move. The laser-cut mickey mouse then spins. With the RGB LED behind the stepper, it reflects three lights on the side of the box through the transparent mickey mouses. I have set the colors into different light sensitivity to express the best color out of the RGB LED.

Jack in the Box
(Laser Cutter)

3D printed Mechanical Automaton

The idea is to have the cat interact with the mouse while spinning the handle in the back. The project contains 12 parts. Inside of the mechanism, I have placed three gears on the tubes to attach to each other. The idea is to spin any of the tubes to trigger the gears to move. Therefore, 3 of them can move simultaneously. For the design, in order to show some part of the largest gear, I cut off the middle of the yellow board. One thing to point out is that the size of the gear differs from each other. For example, I organized them by having the smallest gear on the top and the largest at the bottom.

INFO 4320: Projects

Behind the Scene

RGB LED

The principle of operation

I basically collected an RGB LED, a speaker, a range finder, and two wires for this project. I connected the RGB LED into the ground, pin 32, pin 14, and pin 22. I connected the buzzer into pin 23 and ground. I also connected the range finder into an analog pin, a USB pin since it needs 5 volts and to be grounded. I connected the short uncoated wire into a 3.3V pin on the breadboard, so when it touches another wire, it brings the voltage to the longer wire to change its voltage. In the end, the longer wire is connected to I/O pins where it does not receive any current or signals.

Jack in the Box

The principle of operation

In order to operate the box, I applied potentiometer associates with the servo. Then, the servo turns depending on the value of the potentiometer.
I used analog read for the potentiometer to trigger the servo. Also, I used analog read for the photoresistor depending on whether or not it senses the light. I added a resistor for the photoresistor to adjust the value. RGB LED is output and in digital read mode. The servo and the stepper have connected to the breadboard.

3D printed Mechanical Automaton

Assemble the Box

I designed a 0.5 cm diameter for the smallest gear for the tubes to go through. A 1 cm diameter for the middle gear and the largest gear. The length of the front and back is close to 17 cm. The distance between the yellow object is 5.4 cm to fit the white front and white back objects. The length of the cat is close to 8 cm while the thickness is 0.8 cm. The same thickness for the mouse, but the length of it is 3 cm. With this length, the cat would be able to catch the mouse; however, in the video demonstration, I placed the two apart from each other, so it’s easier to see how the cat and the mouse interact with each other.