ServoVis

Vision + ESP32 2‑servo controller.

Video: https://youtu.be/oHfYfc69wVg

ServoVis has two parts:

• ESP32 hosts a tiny web server with a /set endpoint that sets servo angles.
• Python reads an IP camera stream, finds a dark dot in the image, and (optionally) sends angles to the ESP32.

Repository contents

• esp32code.ino — ESP32 Wi‑Fi web server + servo control
• pythonscript.py — OpenCV dot detection + optional tracking

Quick start

1) Hardware

• ESP32
• 2× hobby servos (base + joint)
• External 5V supply for servos (recommended)

Default pins (edit in esp32code.ino if needed):

• Base servo: GPIO 15
• Joint servo: GPIO 13

Important: share GND between ESP32 and the servo power supply.

2) Flash the ESP32

1. Open esp32code.ino in Arduino IDE.
2. Set ssid and password.
3. Upload.
4. Open Serial Monitor @ 115200 and note the printed IP address.

You can also visit http://<esp32-ip>/ to use the built‑in UI.

3) Install Python deps

python3 -m pip install -r requirements.txt

4) Run

Update the ESP32 and camera URLs (CLI flags shown here):

Demo mode (default): shows video and moves through 3 hardcoded poses.

python3 pythonscript.py --mode demo --esp32 http://192.168.10.5 --camera http://192.168.10.3:4747/video

View only: just see detection overlays.

python3 pythonscript.py --mode view --camera http://192.168.10.3:4747/video

Track mode: follow the detected dot (press q to quit).

python3 pythonscript.py --mode track --esp32 http://192.168.10.5 --camera http://192.168.10.3:4747/video

How the /set endpoint works

Supported query formats:

• /set?base=<0-180>&joint=<0-180> (used by the Python script)
• /set?joint=base&angle=<0-180> (used by the ESP32 web UI)

Calibration notes (optional)

The function pixel_to_angles() in pythonscript.py linearly interpolates angles using corner_angles. If your mechanics differ, adjust corner_angles to match the angles needed when the dot is in each corner.

Troubleshooting

• ESP32 UI loads but buttons do nothing: ensure the ESP32 is on the same network and you’re visiting http://<esp32-ip>/.
• Servo jitter / brownouts: power servos from a separate 5V supply and share GND with the ESP32.
• No video: confirm the IP camera URL plays in a browser/VLC.
• Detection is noisy: adjust the contour area filter and thresholding settings in pythonscript.py.

Safety

This can move unexpectedly. Keep hands clear and start with low-power / small servos while tuning.