Imagine the scene: a humble Python script, operating much like the digital eyes of our operation, tirelessly retrieves visual frames from a webcam in real-time. Then, in a triumphant demonstration of machine learning, it meticulously scans these frames, engaging in a relentless pursuit for the identification of specific objects.
Upon the triumphant detection of our predefined object classes, it doesn't just celebrate quietly. Oh no, it promptly dispatches a directive, reminiscent of a sci-fi communique, to the waiting, ever-ready Arduino board. This board, the unassuming nexus of our setup, controls an actuator - a rather nifty servo, to be precise.
And what's that, you ask, connected to this servo? It's no less than the water pistol of destiny! Now imagine employing this intricate setup to playfully deter a host of intruders - birds, cats, perhaps even an unsuspecting passerby. With this awe-inspiring fusion of Python, Arduino, and a bit of creative water usage, your space is your fortress, and you, the techno-wizard of its defense!
┌──────────────────────┐ ┌────────────────────┐ ┌──────┐
│ │ Webcam Frame │ │ ┌┘ │
│ sentry.py ◄───────────────────────────┤ ├────┘ │
│ │ USB │ Webcam │ │
│ │ │ │ │
│ Running on a PC │ │ ├────┐ │
│ │ │ │ └┐ │
│ │ │ │ └──────┘
└───────────────┬──────┘ └────────────────────┘
│
│ /dev/ttyACMXX USB serial
│ ┌─────────────────────┐
│ │ ├──┐ Water
│ │ Water Pistol │ ├───────────────►
▼ │ ├──┘
┌────────────────┐ └─┬─────┬──┬──┬───────┘
│ │ │ │ │ │
│ │ Pin 9 (PWM) │ └──┴──┤
│ Arduino ├───────────────────────────┼─────►Servo│
│ │ +5V, GND │ ┌─────┘
│ │ └─────┘
└────────────────┘
Install the required Python modules (assuming Python 3 is installed on your system):
pip install pyserial
pip install opencv-python
pip install numpy
Download the YOLOv3 network:
wget https://pjreddie.com/media/files/yolov3.weights
wget https://github.com/pjreddie/darknet/raw/master/cfg/yolov3.cfg
Download the Arduino IDE
https://www.arduino.cc/en/software
Upload the Arduino sketch in the following subfolder to your Arduino board:
arduino_sentry/arduino_sentry.ino
The Arduino is connected to the servo motor (yellow cable) via PIN9. Black is ground and red is connected to 5V.
Connect the Arduino via USB to your computer. Check the serial port, it should normally be something like
/dev/ttyACM0
If not, modify sentry.py and adjust the following variable:
TRIGGER_SERIAL
Run the main script:
python3 sentry.py
- Arduino Board. I'm using a M0 Pro, but probably any Arduino that can control a servo should work.
- Electric Water Pistol
- Webcam. Most USB webcams should work.
- A servo motor with PWM control
- Two cable ties to attach the servo motor to the trigger of the water pistol
The overengineered solution to a pidgeon problem by Max Nagy: https://maxnagy.com/posts/pigeons/
Another improvement would be the direct control of the trigger pins. Then no servo motor is required.
