Inspiration
When we were freshmen, someone kept stealing our chicken nuggets from the community fridge on our floor. We wanted to make sure no one would ever suffer from thievery the way we had, at least without the thief getting verbally berated.
What it does
Our device uses an Arduino Pro Mini and connected accelerometer to measure minute changes in motion. When a change is detected, the Arduino plays a .wav audio clip from an attached SD card reader over a simple audio amplifier and speaker. The sound alerts bystanders or the owner of the food (or valuable) to the attempted theft.
How we built it
We first prototyped our device with a breadboard and programmed the Arduino using the Arduino IDE. Since the accelerometer is an analog sensor, we only had to import libraries to support the SD card reader and audio playback function. To measure changes in motion, we wrote a program that stores accelerometer measurements in 3 separate integer variables (X,Y, and Z), waits for a user defined delay period, and then takes 3 more measurements. By calculating the difference (dX, dY, dZ) in motion along each axis and determining if said difference is greater than a user defined threshold, we can determine if the object is being moved. The threshold and delay period variables allow us to adjust the sensitivity of the device. After prototyping with a breadboard, we designed the circuit in Autodesk EAGLE and milled a 1 sided PCB to accommodate all of the components of the device.
Challenges we ran into
We had some difficulty exporting the Eagle board file as the proper CAM files, but eventually we got everything sorted thanks to a very helpful PI at the Invention Studio.
Accomplishments that we're proud of
We're really proud that our device actually works. We did a hackathon recently where we ran into tons of issues that ultimately lead to an incomplete and unsatisfying final product. Beyond that, we're really excited that our device is very reliable. In our tests the audio alarm was triggered on nearly every attempt at theft. We were also able to set up a speaker and amplifier, troubleshoot circuit problems, and use a PCB mill. All of these things neither of us had a significant amount of experience with, especially outside of classes, so it was really exciting to be able to realize our project with components we had never used before.
What we learned
Apart from the infinitely powerful bond of friendship and teamwork, we learned and developed a number of maker-related skills, including using new machines like a PCB mill, drill press, and audio amplifier. Additionally, we were able to learn about effective and efficient solutions to troubleshooting Arduino issues, amplifier power shortages, speaker malfunctions, PCB board errors, and a number of other problems. Building in a competitive setting only increases the stress of finding solutions and the cost of delays and malfunctions, so we learned a great deal about keeping our cool and adjusting to new situations.
What's next for STOOPID IM NOT EVEN GONNA LET YOU GET THE CHANCE
We see great opportunities for our brainchild. One thing that we didn't have the chance to do due to time constraints was extend the project by adding compatibility with other devices. We hope to be able to control the device from a mobile device or desktop, allowing us to program messages, arm and disarm the device, and adjust other settings based on the desires of the user. We also hope to extend the device to other products, such as valuable objects and allowing for the programming of even more phrases, both positive and negative. In terms of hardware, given more time and resources we hope to make the device a bit more compact as well as design a cool enclosure for the device.
Built With
- accelerometer
- arduino
- cookie
- drill-press
- love-<3
- pcb
- soldering-iron
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