MEMS electrochemical angular accelerometer: a paradigm shift for attitude detection and control in rotorcraft UAVs

Area of Science:

• * Aerospace Engineering
• * Mechanical Engineering
• * Sensor Technology

Background:

• * Accurate attitude estimation in Unmanned Aerial Vehicles (UAVs) is crucial for dynamic control.
• * Conventional methods using gyroscope signal differentiation suffer from phase lags and noise amplification, impacting flight stability.
• * There is a need for direct, high-fidelity angular acceleration measurement to overcome these limitations.

Purpose of the Study:

• * To propose and develop a high-performance MEMS-based electrochemical angular accelerometer (EAA).
• * To enable direct and low-latency measurement of angular acceleration for improved UAV attitude control.
• * To validate the performance of the EAA through theoretical modeling, fabrication, and flight testing.

Main Methods:

• * Theoretical modeling and finite element optimization were used to design a compact plate-type electrode structure.
• * A Glass-on-Silicon (GOS) package was employed for the Micro-Electro-Mechanical Systems (MEMS) device.
• * Performance was evaluated using open-loop turntable tests and closed-loop flight tests with an Incremental Nonlinear Dynamic Inversion (INDI) controller.

Main Results:

• * The fabricated EAA achieved a sensitivity of 4.5 V/(rad/s²) and a noise floor of 3.12 × 10⁻⁶ (rad/s²)/√Hz.
• * Ultra-low power consumption of 2.4 mW was recorded.
• * Flight tests demonstrated faster command responsiveness and reduced tracking errors compared to gyroscope-derived estimates, with a compensated bandwidth up to 10 Hz.

Conclusions:

• * The developed EAA offers a direct sensing paradigm for high-fidelity angular acceleration measurement.
• * This technology significantly enhances the dynamic control and attitude estimation accuracy of UAVs.
• * The EAA addresses the limitations of conventional methods, paving the way for more stable and responsive flight control systems.