In order to further improve the performance of dual-band infrared and magnetic fusion attitude measurement method, an interactive multi-model extended Kalman filter(IMMEKF) attitude fusion algorithm is proposed to calculate the rotating missile's full attitude angle by using the data collected from dual-band two-axis infrared sensors and three-axis geomagnetic sensor. Four filtering models are used to solve the problem of inaccurate in the single model filtering process. The interactive multi-model (IMM) and extended Kalman filter (EKF) attitude estimation algorithms are combined by the probability density function, and is used to update the model probability in real time. Each model's probability weights are modified to achieve the optimal attitude angle estimation according to the environment. The semi-physical experiments results show that IMMEKF algorithm has higher accuracy and reliability compared with other latest state-of-the-art fusion estimation algorithms under normal infrared and geomagnetic conditions. In the case of infrared or geomagnetic anomalies, only the IMMEKF algorithm can avoid using the affected sensor data and calculate an accurate value of attitude angle. The reliability of the dual-band infrared and geomagnetic combined attitude estimation method is improved, which provides an effective technical implementation for the rotating missile attitude measurement.

Concerning on the problem of low measuring precision of the current micro-inertial sensors, a novel attitude measurement method is proposed to dismiss the drift for remarkable attitude error. According to the output of the onboard three-axis magnetic sensor in the process of projectile flight, a low-cost attitude detection system is designed by using the intersection ratio of the sensor. First, the output model of the onboard three-axis magnetic sensor is established. The mathematical relationship between the characteristic ratio of magnetic sensor output and the pitch angle is then derived. Then, the solution and correction algorithm of the attitude angles are studied. Finally, the effectiveness of the attitude measurement method has been validated by carrying out the semi-physical experiments. The experimental results indicate that the error of attitude angles is within ±1° and the attitude angle error of the combined magnetic sensors is not cumulative. Meanwhile, the geomagnetic field strength is dispensable during the whole calculation process. Compared with the “Zero Crossing Method”, the proposed method has shown a nearly two-times higher accuracy and has no limitation of “MAGSONDE window”. What is more, this method proves to be more simple and has a doubled update rate in attitude angle calculation.

As this study examined the issue of surface acoustic wave (SAW) torque sensor which interfered in high rotational speed, the gyroscopic effect generated by rotation was analyzed. Firstly, the SAW coupled equations which contained torque and rotation loads were deduced, and the torque calculation error caused by rotation was solved. Following this, the hardware of the SAW gyroscopic effect testing platform and the turntable experiment were designed to verify the correctness of the theoretical calculation. Finally, according to the experimental data, the gyroscopic effect was compensated by multivariate polynomial fitting (MPF), Gaussian processes regression (GPR), and least squares support vector machine algorithms (LSSVM). The comparison results showed that the LSSVM has the obvious advantage. For improving the function of LSSVM model, chaos estimation of distributed algorithm (CEDA) was proposed to optimize the super parameters of the LSSVM, and numerical simulation results showed that: (1) CEDA is superior to traditional estimation of distributed algorithms in convergence speed and anti-premature ability; (2) the performance of CEDA-LSSVM is better than genetic algorithms (GA)-LSSVM and particle swarm optimization (PSO)-LSSVM. After compensating by CEDA-LSSVM, the magnitude of the torque calculation relative error was 10⁻⁴ in any direction. This method has a significant effect on reducing gyroscopic interference, and it lays a foundation for the engineering application of SAW torque sensor.