Esp32-cam hw

ESP32-Cam Autonomous MQTT Camera

Concept

This circuit realizes an autonomous, battery-powered surveillance camera based on the ESP32-Cam (AI-Thinker model).

Functionality

• Autonomous Operation: Designed for long-term battery use.
• Interval Capture: The ESP32 wakes up at defined intervals, captures a photo, and sends it via WiFi/MQTT to a Home Assistant instance.
• Power Efficiency: Uses Deep Sleep mode between cycles to minimize power consumption.
• Manual Trigger: A tactile button allows manual image triggering at any time.
• Status Indication: Two LEDs provide visual feedback for status or errors (e.g., connection issues).

Project Structure

The repository is organized to separate hardware design from firmware development while maintaining a unified workspace.

esp32-cam-system/           # Root directory (Open this in VS Code)
├── .gitignore              # Global ignore rules for PIO and KiCad
├── platformio.ini          # Central configuration (redirects to firmware/)
├── README.md               # Project documentation
├── .vscode/                # VS Code specific settings
│   ├── settings.json       # IntelliSense and include paths
│   └── tasks.json          # Build and Upload shortcuts
├── firmware/               # Firmware source files
│   └── src/                # .cpp and .h files (Logic & Headers)
├── hardware/               # KiCad PCB project
│   ├── esp32-cam-hw.kicad_pro
│   └── libraries/          # Local Footprints and Symbols
└── docs/                   # Datasheets, 3D models (STL), and images

Development Environment & Settings

PlatformIO & VS Code

To maintain a clean root directory while keeping firmware in a subfolder, the central platformio.ini is configured as follows:

• Custom Paths: Redirects src_dir and include_dir to the firmware/ folder.
• Hardware Abstraction: PSRAM is explicitly enabled via build flags (-DBOARD_HAS_PSRAM) to handle image processing.
• IntelliSense: The .vscode/settings.json includes ${workspaceFolder}/firmware/src to ensure header files are recognized without errors.

KiCad Workflow

• Portability: All custom footprints and symbols are stored in hardware/libraries/.
• Path Variables: Library paths should use the ${KIPRJMOD}/libraries/ variable to ensure the project remains functional when cloned to different machines.

Hardware Description

Components

Main Board

• U1 (ESP32-Cam AI-Thinker): Core module containing the ESP32-S SoC, camera, and SD card slot.
• J1 (Power Supply): 2-pin JST-XH connector for 5V external power.
• J2 (Programming): 5-pin header for FTDI flashing and UART debugging.
• J3 (Front Panel Link): 4-pin socket to connect the daughterboard.

Daughterboard (Front Panel)

• SW1 (Button): Manual capture trigger, push button DTR 7/RT (Connects IO12 to GND).
• D1 (Red LED): Error indicator (MQTT/WiFi failure).
• D2 (Status LED): Activity indicator (Capturing/Processing).

Connections and Pinout

PCB Milling Specifications (Isolation Milling)

Optimized for CNC isolation milling on copper-clad boards.

Manufacturing Parameters

• Track Width: 0.5 mm to 0.8 mm (Signals); 1.0 mm (Power).
• Clearance (Isolation Gap): 0.4 mm to 0.6 mm.
• THT Pads: Standard 2.0 mm outer diameter (1.0 mm drill). Custom footprints (e.g. SW1 DTR 7/RT) use 2.6 mm pads with 2.0 mm drills to maintain isolation gaps.
• Thermal Reliefs: Required for all pads in copper zones.
• Antenna Cutout: Instead of a standard keepout zone, a rectangle is drawn on the User.Drawings layer. This area under the ESP32-S PCB antenna will be completely milled out (freigefräst) to avoid WiFi signal attenuation.

Milling Constraints

• Tooling: 30° Engraving Bit.
• Depth of Cut: 0.05 mm to 0.1 mm (Auto-leveling highly recommended).