Substrate-decoupled, bulk-acoustic wave gyroscopes: Design and evaluation of next-generation environmentally robust devices
When selecting a MEMS gyroscope, systems engineers and application developers focus on a few key performance parameters. The most common include device sensitivity and bias stability. Sensitivity is important because it refers to the projected output of the device to a certain input rotation. Bias stability, however, has been long considered the “gold standard” specification for gyros and describes the resolution floor of the gyroscope and thereby specifies the detection limitations. The bias of a vibratory gyroscope is the average output recorded from the gyroscope when it is not undergoing any rotation. It is often referred to as the Zero Rate Output (ZRO) and is typically expressed in units of deg/hr or deg/s. Bias stability measurement describes how the bias of the gyroscope may change over a specific period of time under fixed conditions (i.e. constant temperature and pressure).
Engineers now design systems and products that include MEMS sensors, particularly MEMS gyroscopes, as essential components. These applications range from portable and wearable devices to industrial robots and critical automotive safety systems. Their requirements for lower power, smaller form-factor, environmental tolerance and lower cost are growing. To satisfy these needs, today’s design engineers are considering new solutions and new partners who can bridge theory and practice, and connect the lab to the production line. They are looking for innovation and scale.