Optimized Design of an Anti-Rotation and Anti-Overload Structure Based on Missile-Borne Semi-Strap-Down Inertial Navigation System

Abstract

The Semi-Strapdown Inertial Navigation System (SSINS) provides a new solution to attitude measurement of a high-speed rotation missile. However, high dynamic and high overload test environments present significant challenges for attitude measurement systems. As a key component inside the SSINS, the Top-to-top Hemisphere Structure (THS), the rationality of its design greatly affects the navigation accuracy of the SSINS. First of all, this paper abstracts the new optimized THS into the equivalent cantilever beam structure stress model. For the first time, the relationship between the critical condition of plastic deformation at the top of the cavity and the structure parameters of the THS is obtained. Then, starting from the structural design angle of the lower hemisphere, the parameter extraction principle for effectively protecting the top hemisphere and improving the anti-rotation ability of the SSINS is obtained for the first time; furthermore, the uniform sampling method is used to obtain structural parameters satisfying the set conditions. Finally, the THS before and after optimization will be tested for anti-overload and anti-rotation in the same environment. The test results show that the optimized THS can increase the anti-rotation ability of the system to twice that before optimization. In addition, the first proposed THS' s structural optimization method opens up a new idea for the better application of the sensor in SSINS and the improvement of the positioning accuracy in the missile-borne environment.