Improving the accuracy of a platformless inertial navigation system for an aircraft during rapid roll rotation

The article addresses the problem of enhancing the accuracy of an autonomous strapdown inertial navigation system (SINS) for aircraft with rapid rotation about their longitudinal axis. This rapid rotation stabilizes the aircraft's position along the longitudinal axis while imposing strict requirements on the roll gyroscope's scale factor (SF) error in the SINS. This is essential to ensure that the roll angle error remains on par with the pitch and yaw angle errors. A novel method for periodic correction of the roll gyroscope's SF within an autonomous SINS is proposed. The method utilizes signals from a single-axis indicator gyrostabilizer based on a microelectromechanical system (MEMS) gyroscope. The correction involves determining the numerical value of the roll gyroscope's SF error during flight and subsequently compensating for its influence on the roll angular velocity measurements. The functional scheme of the method is presented, along with formulas for calculating the correction coefficient. The efficiency of the proposed approach in improving the accuracy of the SINS is evaluated using a typical inertial module and an indicator gyrostabilizer with a MEMS gyroscope as an example. The method significantly enhances the accuracy of roll angular velocity and coordinate measurements in an autonomous SINS without requiring expensive precision gyroscopes.