A research team led by Prof. ZOU Xudong from the Aerospace Information Research Institute of the Chinese Academy of Sciences (AIRCAS) has proposed a new solution to address two longstanding challenges in Micro-Electro-Mechanical Systems (MEMS) resonant accelerometers: temperature drift and measurement dead zones. By implementing a dual-mode operating scheme that effectively decouples the operating frequencies of the device's differential beams, the team has achieved improvements in the sensor's accuracy and performance.

Their findings were recently published in Microsystem & Nanoengineering.

The study revealed that driving one beam in its first resonant mode while operating the other in its second resonant mode can enhance temperature compensation and mitigate the modal localization effect that typically causes measurement dead zones. The dual-mode design also preserves the geometrical symmetry of the beams, which is critical for minimizing temperature-induced errors and maintaining stable sensor performance.

Experimental data confirms the solution's effectiveness that the dual-mode method reduces temperature-induced drift by more than 280 times compared to conventional approaches. Specifically, after differential compensation, the temperature drift was cut from approximately 342 mg to 1.19 mg. Additionally, analyses of Allan deviation and power spectral density (PSD) revealed a notable reduction in low-frequency noise, which boosts the accelerometer's precision and long-term stability.

Furthermore, the design eliminates frequency overlap between the two differential beams, resolving the dead zone issue that commonly occurs when the beams' operating frequencies intersect.

The researchers emphasized that this dual-mode technique provides a cost-efficient way to enhance MEMS accelerometer performance, making it valuable for applications such as inertial navigation and vibration monitoring.