Ultrafast Mode Reversal Coriolis Gyroscopes

Mode reversal is an advanced technique that can effectively improve the performance of the Coriolis vibratory gyros (CVGs). In this article, we propose and demonstrate a modified mode reversal scheme to reduce the measurement dead zone limitations of state-of-the-art mode switching in CVGs. The dynamic model and working principle of the mode reversal gyro are first reviewed. Theoretical analysis and experimental verification are conducted to describe nonlinearity, mode coupling, and time-varying characteristics. A reversal scheme based on iterative learning control (ILC) is then presented. The experimental results showed 145% improvement in reversal speed and 90% reduction in overshoot when compared to other popular controllers and robustness to environmental variations.