Modified MultiWii flight controller firmware with DHT humidity sensor integration (2014)

Part of Daniel Dieser's drone and IoT experimentation period in Puerto Madryn, Patagonia.

A custom modification of the MultiWii flight controller firmware that integrates a DHT temperature and humidity sensor into the flight system. This was an experiment in adding environmental sensing capabilities to drone platforms -- making drones not just fly, but observe and measure their environment.

In 2014, the idea of drones as environmental monitoring platforms was still emerging. This modification represented an early experiment in:

• Environmental data collection from the air -- temperature and humidity at altitude
• Sensor fusion -- integrating non-flight sensors into a flight controller
• IoT meets aviation -- the same sensors used in weather stations, now flying

This was particularly relevant in Patagonia, where weather changes rapidly and environmental monitoring is critical for fire detection and vegetation analysis -- work Daniel would later pursue with computer vision and YOLO models.

• MultiWii 2.4 -- Open-source flight controller firmware
• QUADX configuration -- Standard X-frame quadcopter
• MPU6050 IMU -- Gyroscope + accelerometer for flight stabilization
• I2C communication -- 100kHz standard mode

• DHT22 -- Digital temperature and humidity sensor
• Connected via GPIO pins on the flight controller
• Data logged alongside flight telemetry

• Motor throttle range: 1150-1850
• ESC protocol: Standard PWM
• Supports multiple board types (Arduino Pro Mini, Naze32, etc.)

• MultiWii/MultiWii.ino -- Main firmware entry point
• MultiWii/config.h -- Hardware configuration and sensor setup
• MultiWii/Sensors.cpp -- Sensor reading and processing (including DHT)
• MultiWii/IMU.cpp -- Inertial measurement unit calculations
• MultiWii/Output.cpp -- Motor output and mixing

This was one of several MultiWii modifications I made during my robotics period. Each mod taught me something different:

• This one (humidity) -- environmental sensing from drones
• Sonar version -- altitude hold for indoor flight
• Sonar v2 -- improved altitude stability

These hardware experiments laid the groundwork for my later computer vision work: if a drone can sense humidity, it can also sense fire, vegetation health, and eventually... network attacks.

GPL v3 -- MultiWii open-source firmware.

Daniel Dieser -- Puerto Madryn, Patagonia, Argentina Telegram: @mrmoz33