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Birdcam

Live stream
I decided to build a bird feeder with a live-streaming camera for my significant other’s birthday. It seems to work pretty well! The system is based on a Raspberry Pi Zero W running the Motion firmware, with an image mask and motion trigger set to activate when birds land on the feeder. Every night, a shell script runs the imagemagick utility to convert all images with the same minute time stamp into fun little combined gifs. This project is a work in progress–automatic image tweeting and imgur uploads should be coming soon! In the meantime, if anyone needs an absolutely massive number of tiny bird gifs, I’m happy to share!

Parts List

Code

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3D Printer Enclosure Fan Controller

Overview

After building my 3D printer enclosure, I ran into the issue of my printer enclosure getting too warm. Temperatures during extended prints were climbing above 130 degrees Fahrenheit, which was causing my printer electronics to overheat, leading to extrusion issues and missed steps. I remedied this by propping the door open with a rag, but that removed the noise damping benefit of the enclosure. An overcomplicated but fun solution in the form of a PID fan controller was devised. This controller uses and Arduino nano to PWM control a logic-level N-channel MOSFET that feeds into a low-pass filter in order to control a 12V radial blower fan with a varying analog voltage. Bit-shifting in the Arduino Nano code takes advantage of the built-in timers in the Atmel Atmega 328p processor in order to generate PWM frequencies at 25kHz, which is outside the range of human hearing and thus less annoying. Initial attempts to control the fan using straight PWM without a low-pass filter proved to be unreliable, but the current setup with the low-pass filter has been running strong for over 6 months as of the writing of this post.

Code

Parts List

Pictures

Electronics
Main menu
Config screen 1
Config screen 2
Controller and fan

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LED Trumpet

Overview

This is my second iteration of my LED trumpet.  The first iteration used an Arduino Nano, but I upgraded to a Teensy this time around for more processing power (gotta get all them FFT’s).  The system is powered by Lipo batteries (from my rc aircraft projects) feeding a Castle 10A SBEC that provides 5V to the Teensy and SK6812 individually addressable LEDs.  There’s an Adafruit microphone module buried inside the 3D printed electronics housing, allowing the LEDs to run an FFT pattern and volume-activated effects.  Three buttons on the side of the electronics housing allow the user to change modes (or play snake, in one of the modes), and a power switch allows the user to easily flick the system on or off with their thumb.  The top of the electronics housing has an LED voltmeter built in to allow the user to monitor the battery voltage of the trumpet.

Code

Parts List

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Fire Alarm Pull Light Switch Cover

I got bored during finals and measured the fire alarm pull outside my dorm room.  Adding a slot to the back allowed me to fit it over my room’s existing light switches, and a dual-color print from PETG gave it a somewhat realistic look.  Shenanigans ensued.

Thingiverse Link

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