SENSOR ARCHITECTURE
Hardware integration deep dives. Understanding drivers, bus priorities, and fusion logic for GPS, Rangefinders, and IMUs.
Hardware Integration
Airspeed Sensors (Pitot)
For fixed-wing aircraft, Airspeed is life. While GPS gives "Ground Speed", only a Pitot Tube measures "Airspeed" (the speed of air over the wings)....
Barometer Physics
The Barometer is the primary source of relative [altitude](/field-manual/mavlink-interface/altitude.html) for most drones. It measures atmospheric ...
GPS Integration
Global [Navigation](/field-manual/navigation-mission/navigation-architecture.html) Satellite Systems (GNSS), commonly referred to as GPS, provide t...
IMU Architecture & Fusion
The Inertial Measurement Unit (IMU) is the heart of the [flight controller](/field-manual/build-guide/flight-controllers.html). It consists of **Gy...
Magnetometer Management
The Magnetometer (Compass) is critical for heading, but also the most problematic sensor due to electromagnetic interference. ArduPilot supports mu...
Optical Flow: Sensor Drivers & Quality
Optical Flow sensors (like the PX4Flow or HereFlow) give drones the ability to hold position without GPS. They work like an optical mouse, tracking...
RPM Sensors: The Harmonic Notch
[Vibration](/field-manual/log-analysis/vibration-analysis.html) is the enemy of stability. Propellers create massive vibration spikes at specific f...
Rangefinders: Tilt Compensation
Rangefinders (Lidar, Sonar, Radar) provide the critical "Height Above Ground" (AGL) metric needed for automated landing and [terrain following](/fi...