Improving the Performance of MEMS GYROS via Redundant Measurements: Theory and Experiments

A redundant sensor array is a device composed of more than one sensor of a given type, for example an array of rate gyroscopes. Previous work has shown that redundancy can enhance the failure tolerance of the sensor suite and can also be leveraged to improve the accuracy of the measurements. This thesis further explores the possibility of improving the performance of low-cost micro-electro-mechanical MEMS gyroscopes using the redundancy concept. To this end, an experimental sensor array test bed is constructed that allows data from up to 12 three degrees of freedom MEMS gyroscopes to be acquired and combined under various geometric configurations. By organizing the MEMS gyroscopes in ideal geometric configurations, it is shown how the effects of sensor noise can be reduced in order to increase the precision of the measurements. Experiments using the constructed sensor array test bed show that the 1-sigma sensor noise can be reduced by nearly 65 percent through the proper combination of multiple measurements using ten 3 degrees of freedom gyros. It is further observed that realizing this improvement relies, in part, upon accurate estimation of the sensor bias. This aspect motivates future work on bias estimation schemes for arrays of sensors.