Example Projects

Complete worked examples demonstrating MetaForge workflows

Table of contents

1. Drone Flight Controller
   1. Project Overview
   2. Requirements (PRD.md)
   3. Generated Artifacts
2. IoT Temperature Sensor
   1. PRD
   2. Workflow
3. Solar Battery Charger
   1. Key Features
   2. Workflow Highlights
4. Smart Home Hub
   1. Architecture
5. Comparison Table
6. Example Repositories
7. Learning Path
   1. 1. Start Simple
   2. 2. Add Complexity
   3. 3. Advanced Project
   4. 4. Your Project
8. Contributing Examples

Drone Flight Controller

A complete example of designing a quadcopter flight controller from PRD to manufacturing files.

Project Overview

flowchart LR
    A[PRD] --> B[Requirements]
    B --> C[Architecture]
    C --> D[Schematic]
    D --> E[BOM]
    E --> F[Manufacturing]

    style A fill:#E67E22,color:#fff
    style F fill:#27ae60,color:#fff

Requirements (PRD.md)

# Drone Flight Controller

## Overview
A flight controller for a 5" freestyle quadcopter with GPS and telemetry.

## Specifications
- 4x motor outputs (DShot600)
- IMU: 6-axis gyro + accelerometer
- Barometer for altitude hold
- GPS for position hold and RTH
- OSD chip for camera overlay
- Telemetry: 2.4GHz (ELRS) + 900MHz (backup)
- Input voltage: 7-26V (2-6S LiPo)
- USB-C for configuration
- SD card for blackbox logging

## Constraints
- Size: 36mm x 36mm (30.5mm mounting holes)
- Weight: < 15g
- 4-layer PCB
- All SMD components
- Cost target: < $30 BOM

Generated Artifacts

constraints.json:

{
  "electrical": {
    "supply_voltage": { "min": 7, "max": 26, "unit": "V" },
    "motor_outputs": 4,
    "protocols": ["DShot600", "ELRS", "GPS"],
    "interfaces": ["USB-C", "SD", "SPI", "I2C", "UART"]
  },
  "mechanical": {
    "dimensions": { "x": 36, "y": 36, "unit": "mm" },
    "mounting_pattern": "30.5mm",
    "pcb_layers": 4,
    "max_weight": 15
  },
  "performance": {
    "gyro_update_rate": 8000,
    "loop_frequency": 4000
  },
  "cost": {
    "target_bom": 30,
    "currency": "USD"
  }
}

architecture.md (excerpt):

# Architecture

## Block Diagram

## Component Selection

### Microcontroller
- **Part**: STM32H743VIT6
- **Rationale**:
  - 480MHz Cortex-M7
  - Sufficient I/O for all peripherals
  - Hardware floating-point for PID loops

### IMU
- **Part**: BMI270 (gyro) + BMP390 (baro)
- **Rationale**:
  - Low noise, high update rate
  - Proven in flight controllers

### Motor Drivers
- **Part**: 4x DRV8323RS
- **Rationale**:
  - Integrated gate drivers
  - Supports DShot protocol

IoT Temperature Sensor

Simple battery-powered WiFi temperature sensor.

PRD

# WiFi Temperature Sensor

## Requirements
- Temperature range: -40°C to 125°C
- Accuracy: ±0.5°C
- WiFi 2.4GHz
- Battery: CR2032 coin cell
- Sleep current: < 10µA
- Sample every 60 seconds
- Target battery life: 1 year

## Form Factor
- < 30mm diameter (fit in standard enclosure)
- Single-sided PCB

Workflow

# 1. Setup
forge setup
forge onboard

# 2. Requirements
forge run spec
# → Generates constraints.json

# 3. Architecture
forge run architecture
# → Selects ESP32-C3, BME280, coin cell holder

# 4. Power Budget
forge run power
# → Calculates 8 months battery life with CR2032
# → Suggests CR2450 for 12+ months

# 5. Schematic Plan
forge run schematic-plan
# → Outlines circuit topology

# 6. BOM
forge run bom
# → Gets pricing: $4.50 BOM @ 1000 units

Solar Battery Charger

Solar panel battery charger with MPPT.

Key Features

• 18V solar panel input
• Charges 12V lead-acid or LiFePO4
• MPPT algorithm for efficiency
• LCD display for voltage/current
• Temperature compensation

Workflow Highlights

Power Budget Agent:

{
  "input_power": {
    "solar_max": 100,
    "solar_typical": 60,
    "unit": "W"
  },
  "charging_profiles": {
    "lead_acid": {
      "bulk": { "voltage": 14.4, "current_max": 7 },
      "float": { "voltage": 13.6, "current_max": 1 }
    }
  },
  "efficiency": {
    "mppt": 0.96,
    "converter": 0.92,
    "overall": 0.88
  }
}

Smart Home Hub

Central controller for home automation.

Architecture

flowchart TB
    A[ESP32-S3] --> B[WiFi/BLE]
    A --> C[Zigbee Radio]
    A --> D[Ethernet]
    A --> E[USB Host]

    C --> F[Zigbee Devices]
    D --> G[Router]
    E --> H[Peripherals]

    A --> I[Display]
    A --> J[SD Card]

    style A fill:#3498db,color:#fff

Comparison Table

*Dev time with MetaForge vs. 2-5x longer manually

Example Repositories

Each example project is available as a complete repository:

• drone-fc - Flight controller
• iot-sensor - Temperature sensor
• solar-charger - MPPT charger
• home-hub - Automation hub

Each repository includes:

• Complete PRD.md
• All generated artifacts
• KiCad schematic and PCB
• BOM with supplier links
• Manufacturing files (Gerbers, pick & place)
• Firmware skeleton

Learning Path

1. Start Simple

Begin with the IoT Temperature Sensor - demonstrates core workflow without complexity.

2. Add Complexity

Move to Battery Charger - introduces power electronics and multiple agents.

3. Advanced Project

Tackle Drone Flight Controller - full complexity with high-speed design.

4. Your Project

Apply learnings to your own hardware idea.

Contributing Examples

Have a cool MetaForge project? Share it!

1. Fork metaforge-examples
2. Add your project
3. Include complete documentation
4. Submit PR

← API Reference • Contributing →