Thorsten Balslink

100 kHz MEMS Vibratory Gyroscope

The behavior of MEMS rate gyroscopes depends on the sensors resonance frequency f0. Key features like robustness against external vibrations and ease of integration can be optimized by increasing f0. We designed and fabricated a device with f0=100 kHz for experimental and theoretical investigation of MEMS vibratory gyroscopes with increased f0. The frequency of 100 kHz is significantly above the typical f0 of current gyroscopes which is in the range of 10 kHz to 30 kHz. Measurements prove that key parameters that are theoretically derived from a 15 kHz reference model can be scaled to 100 kHz with good accuracy. It is shown that the increase of f0 to 100 kHz has-on the one hand-design trade offs like a much lower sensitivity and higher quadrature and-on the other hand-major advantages like the significantly improved vibration robustness.

A 3-Axis Gyroscope for Electronic Stability Control With Continuous Self-Test

Gyroscopes and accelerometers form the core of Electronic Stability Control (ESC) systems [1], which are mandated for new vehicles in many countries. Gyroscopes for ESC applications require higher performance specifications than those of consumer gyroscopes available in the market today. In addition, they require continuous safety monitoring so that changes in the output, which happen in the field due to MEMS and circuit malfunctions, are flagged and are not misconstrued for legitimate signals. This work presents a low-overhead approach for implementing accurate continuous safety monitoring by augmenting the function of already existing sub-systems. In addition, the paper discusses circuit architecture and design techniques, which achieve the stringent ESC specifications for noise, robustness to parasitic resonant modes in the sensor element and offset drift due to temperature and Electro-Magnetic Interference (EMI).

A 100 kHz vibratory MEMS rate gyroscope with experimental verification of system model's frequency scaling

The working frequency f0 of vibratory MEMS angular rate sensors is a main optimization parameter. To investigate the specific challenges of increasing f0 we designed a new device with f0=100 kHz. Key parameters of the 100 kHz device are theoretically and experimentally compared with those of a 15 kHz reference sensor. The experimental results show the validity of the theoretical frequency scaling of the key parameters. The measurements show benefits and disadvantages of MEMS vibratory gyroscopes with increased f0>;>;30 kHz.