Multi-Platform Flight Control Stack Tuning and Troubleshooting
Flight Control Tuning
AOS RC provided remote diagnostic log analysis and on-site field tuning to resolve stability, control, and vibration issues across three distinct commercial drone platforms. We optimised the flight control stacks to improve operational safety and pilot handling precision.
Technical challenge
The client faced separate technical bottlenecks across three unique airframe configurations. The first platform exhibited high noise on the yaw axis and severe propeller blade flutter at high throttle settings. The second platform suffered from critical pitch oscillations that made the aircraft difficult to control, alongside motor saturation where the power plants frequently reached maximum output. The third platform experienced vertical instability and altitude oscillations when vertical acceleration parameters were increased.
Engineering approach
We used a structured troubleshooting workflow combining telemetry log analysis with iterative on-site flight tests using enterprise open-source flight stacks.
Vibration Filtering and Input Response: For the first platform, log analysis isolated the yaw axis noise to mechanical tolerances within the folding arm mechanism. We resolved this by applying a targeted 100Hz gyroscopic filter on the yaw axis. To improve slow response to stick inputs, we increased feedforward gains on pitch and roll, which restored sharp tracking.
Control Loop Diagnostics: For the second platform, flight logs showed that the flight control algorithms were executing commands accurately, indicating an external hardware issue rather than a tuning error. Physical inspection revealed asymmetrical motor tilt angles that reduced yaw authority. Once corrected, we changed the speed controller configuration from velocity control to direct pulse-width modulation (PWM) mode, reducing peak motor saturation from 100 percent to 90 percent. Continuous telemetry tracking isolated the remaining oscillation to a faulty component in the ground control station unit, which was replaced.
Altitude and Position Tuning: For the third platform, we optimised the vertical tracking loops. To eliminate oscillations caused by aggressive vertical acceleration, we adjusted the altitude controller by adding a derivative term, reducing the proportional gain, and applying feedforward compensation. Position-hold parameters, including horizontal acceleration and jerk limits, were also calibrated to improve positional accuracy.
Outcomes
Resolved critical flight instabilities across three distinct commercial product lines, establishing stable aircraft handling in all primary flight modes.
Eliminated motor thrust saturation on the secondary platform, restoring a 10 percent power margin to protect the aircraft during high-velocity manoeuvres.
Optimised vertical and horizontal tracking precision through systematic control loop and notch filter configuration.
Delivered fully validated configuration parameter files and technical documentation to support the client's internal operations.