Robotic Rover

An ESP32-based robotic rover project combining a WiFi-controlled driving platform, a live camera feed, and a servo-driven robotic arm. The rover is operated from a phone or computer browser over WiFi — no app required.

Note: This is a partially confidential project; only the firmware sketches in this repository are shared publicly.

Overview

The project is split into three independent Arduino sketches, each flashed to an ESP32 / ESP32-CAM board. They expose simple web interfaces and a lightweight key,value text protocol over WebSockets for control.

Sketches

CAM_Router.ino

The main rover controller for an ESP32-CAM (AI-Thinker) board. It:

• Drives a two-motor differential-drive chassis through an H-bridge (forward / backward / left / right / stop).
• Serves a self-contained mobile-friendly control web page at /.
• Streams live camera frames to the browser over a /Camera WebSocket.
• Receives drive, speed, and light commands over a /CarInput WebSocket.
• Also exposes a simple HTTP /control?command=forward|backward|left|right|stop endpoint for scripted control.
• Controls an on-board LED/light via PWM.

Robot_Arm_router.ino

Controls a 4-servo robotic arm (Base, Shoulder, Elbow, Gripper) on an ESP32:

• Serves a browser slider UI at / for live control of each joint.
• Communicates over a /RobotArmInput WebSocket.
• Supports record and playback of arm motion sequences (record joint moves, then replay them with their original timing).

OpenCV_Cam.ino

A minimal MJPEG/JPEG image server for an ESP32-CAM (AI-Thinker), intended as a camera source for OpenCV / computer-vision pipelines on a host machine. It serves still JPEG frames at three resolutions:

• /cam-lo.jpg — 320x240
• /cam-mid.jpg — 350x530
• /cam-hi.jpg — 800x600

RoverUtils.h (helper library — added)

A header-only collection of reusable, opt-in helpers shared across the sketches:

• clampServoAngle() / clampPwm() / clampInt() — keep servo angles (0–180) and PWM duty values (0–255) within safe limits so a bad command can never drive hardware out of range.
• parseKeyValue() — parse the project's key,value command protocol with malformed-input rejection.
• connectWiFi() — connect to WiFi with a timeout instead of blocking boot forever when the access point is unreachable.

See the file header in RoverUtils.h for usage examples.

Hardware / Wiring Overview

Component	Notes
ESP32-CAM (AI-Thinker)	Camera + WiFi for CAM_Router.ino / OpenCV_Cam.ino
ESP32 dev board	Runs Robot_Arm_router.ino
L298N / TB6612 H-bridge	Drives the two chassis motors
2x DC gear motors	Differential drive (left / right)
4x hobby servos	Robot arm: Base, Shoulder, Elbow, Gripper
LED / light	PWM-controlled illumination

Motor pins (CAM_Router.ino):

• Right motor: EnA 12, IN1 13, IN2 15
• Left motor: EnB 12, IN3 14, IN4 2
• Light: GPIO 4

Servo pins (Robot_Arm_router.ino):

• Base 27, Shoulder 26, Elbow 25, Gripper 33 (all default to 90°)

Camera pins: standard AI-Thinker ESP32-CAM pin map (see sketch source).

Configuration

Before uploading, set your WiFi credentials at the top of each sketch:

const char* ssid     = "YOUR_WIFI_SSID";
const char* password = "YOUR_WIFI_PASSWORD";

Build & Upload (Arduino IDE)

1. Install the Arduino IDE (1.8+ or 2.x).
2. Add the ESP32 board support URL in File → Preferences → Additional Boards Manager URLs: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json then install esp32 by Espressif Systems via Tools → Board → Boards Manager.
3. Install the required libraries via Sketch → Include Library → Manage Libraries:
   • ESPAsyncWebServer and AsyncTCP (for CAM_Router.ino and Robot_Arm_router.ino)
   • ESP32Servo (for Robot_Arm_router.ino)
   • esp32cam (for OpenCV_Cam.ino)
4. Select the correct board:
   • AI Thinker ESP32-CAM for CAM_Router.ino / OpenCV_Cam.ino
   • your ESP32 dev board for Robot_Arm_router.ino
5. Open the desired sketch, set WiFi credentials, then Upload. (For ESP32-CAM, hold/wire the board into flash mode as required by your USB-to-serial adapter.)

Usage

1. After upload, open the Serial Monitor at 115200 baud to read the device's assigned IP address.
2. Rover / Arm: browse to http://<device-ip>/ from a phone or computer on the same network and use the on-screen controls.
3. OpenCV camera: request frames from http://<device-ip>/cam-lo.jpg (or -mid / -hi) in your CV application.

Repository Layout

Robotic_rover/
├── CAM_Router.ino          # Rover drive + camera streaming web controller
├── Robot_Arm_router.ino    # 4-servo robot arm controller with record/playback
├── OpenCV_Cam.ino          # Multi-resolution JPEG camera server for OpenCV
├── RoverUtils.h            # Shared, opt-in safety/parsing/WiFi helpers
├── .gitignore
└── README.md