Dynamic Modeling of a novel microfluidic channel angular accelerometer

摘要

The angular accelerometer is a versatile inertial instrument, with applications ranging from vehicle stabilization to navigation and satellite pointing. A novel angular accelerometer is proposed, which is able to improve on contemporary angular accelerometers and micro-electromechanical system gyroscopes. The sensor consists of micro-machined spiral channels, fabricated on multiple wafers and used to construct a spiral-helix fluid column that generates high pressure during angular acceleration round the sensitive axis. The two ends of the fluid column are joined at a central measurement chamber, where a diaphragm-based pressure transducer produces a signal proportional to the angular acceleration applied. This article presents the dynamics of the sensor, and then investigates its potential. A discrete multiple-degree-of-freedom model simulates pressure generation and propagation, and was verified experimentally. Channel flow is simulated by means of a model derived from Szymanski's theory of unsteady laminar flow. The pressure transducer diaphragmmodel is based on linear flat plate theory. The sensor theory is synthesized in a linear sensor model and the dynamic response optimized by means of the Kuhn-Tucker method. A simulation study demonstrated that a sensor with a resolution of 15 mu rad/s(2) and a bandwidth of 50 Hz can be packaged with a diameter of 22 mm and a height of 22 mm, when referenced against a noise level of 1 mu V/root Hz.