The Sentry

Inspiration

The idea was basically a simple alarm system, and a rubber band gun seemed like a fun twist. Name inspired by the Sentry Gun from Call of Duty.

What it does

It's an alarm system with a built in rubber band gun and a web panel that allows you to arm/disarm it, toggle it's laser, and change the color of it's LED. It uses an ultrasound distance sensor for detecting motion. When the alarm is tripped, it can fire up to two rubber bands at intruders.

How I built it

All the electronics are breadboarded/jumper wired together, code for the ESP32 is written in CircuitPython, and all CAD was done in OnShape

Challenges I ran into

Aside from minor hardware challenges, a major programming issue I ran into was CircuitPython's lack of support for asynchronous/threaded python.

Accomplishments that I'm proud of

• Simple, easy-to-use web UI
• Easily 3d printable case
• Laser for alignment

What we learned

Touched up on CircuitPython, and his was my first time using an ESP32.

What's next for The Sentry

Probably a lot of software upgrades, mainly to give you more control over how it operates.

Built With

• circuitpython
• css
• html
• javascript
• onshape
• python