Identification and Closed-Loop Control of High-Performance Accelerometers

We are reporting on interfacing methods for low-noise, wideband accelerometers. The open-loop system is designed to operate with a high-quality factor to improve its noise performance. To circumvent the practical issues related to using high-Q systems, we investigated and implemented methods to identify the device characteristics in real-time and used them to develop an adaptive, frequency-selective controller. This approach not only enables the use of these high-Q devices but also allows for compensating the changes in device response over its life. We demonstrated that the approach could be successfully implemented on devices with quality factors as high as 120.