🚀 Architectural Analysis of ESP32 and STM32 for Low-Cost Drone Flight Controllers

At OrbeezLabs, we're building more than just another drone—we're developing a fully custom, open-source flight controller to explore how microcontroller architecture impacts real-world flight performance.

Our research compares two popular embedded platforms:

🟢 ESP32 DevKit (Dual-core, up to 240 MHz)

🔵 STM32F401 Blackpill (ARM Cortex-M4 with deterministic hardware FPU)

The key question we're investigating is:

Does a higher clock speed always outperform a dedicated Floating-Point Unit (FPU) in real-time drone control? 🤔

🎯 Project Objective

To answer this, we're building two nearly identical flight controllers. Both versions use the same:

• 🧩 Sensors (MPU6050 & BMP280)
• ⚡ Power circuitry
• 🔋 Power Distribution Board (PDB)
• 🚁 Motors & ESCs
• 📐 PCB design
• 🧠 PID control algorithms

The only major difference is the microcontroller, allowing us to fairly compare their real-world performance.

📊 What Are We Measuring?

Instead of synthetic benchmarks, we're focusing on practical flight performance, including:

✅ PID loop execution time

✅ Flight stability

✅ Control latency

✅ CPU utilization

✅ Floating-point computation efficiency

✅ Power consumption

Our goal is to determine which architecture offers the best balance of performance, reliability, and cost for low-cost UAV applications. 🚁

🛠️ Hardware Progress

The hardware development is well underway!

✔️ Custom schematic design

✔️ PCB design & manufacturing

✔️ Component sourcing

✔️ Hardware assembly

✔️ Sensor integration

✔️ Prototype development

Both the ESP32 and STM32 flight controllers have been designed with nearly identical hardware to ensure a fair comparison.

💻 Firmware Development

We're currently developing the software that powers the flight controller, including:

🧠 PID flight control

📡 Sensor drivers

📈 Sensor fusion

⚙️ ESC communication

⚡ Performance optimization

🛡️ Flight stability testing

Every module is designed to keep the software consistent across both platforms so that only the processor architecture influences the results.

🌍 Why Open Source?

We believe innovation grows through collaboration. Once the project reaches a stable stage, we'll release:

📂 PCB design files

📜 Schematics

💻 Firmware source code

📖 Documentation

🔧 Build instructions

🎥 Flight demonstrations & technical reports

Whether you're a student, researcher, hobbyist, or embedded systems engineer, you'll be able to study, build, and improve the platform.

🚀 What's Next?

The next phase includes:

✈️ Firmware integration

🧪 Ground & flight testing

🎯 PID tuning

📊 Performance comparison between ESP32 and STM32

📹 Sharing development updates and technical insights

Our mission is simple: build an affordable, transparent, and research-driven flight controller that helps the embedded and drone development community better understand how microcontroller architecture influences real-world UAV performance.

Stay tuned there's much more to come! 🚁✨