Flight testing for Dual GPS Support on PX4

Ascend Engineering has conducted the official testing of the dual GPS configuration for heading determination included in PX4 1.16. This important validation of Jacob Dahl's bugfix ensured this feature update made it into the latest release of PX4.

The implementation uses two GPS units connected via CAN bus through a CAN splitter into the flight controller. The system designates one receiver as the rover (Instance 0) and the other as the moving base (Instance 1). Heading data flows from the moving base GPS to the rover, which then generates and stabilizes the heading for the flight controller.

Why Dual GPS Heading Matters

Dual GPS heading allows operators to calculate heading when the compass is near large metal objects or machinery, where magnetometer performance is degraded. This makes a dual antenna setup well-suited for surveying and urban inspection applications, as well as powerline inspections or other environments with electromagnetic interference. The configuration also provides more accurate and repeatable turns compared to compass-based heading, which benefits any mission where precise orientation matters.

Example Field Test Results

We expect to continue testing and supporting development through 2026, with findings contributed back to the open source drone developer community.