Research On Rocket Attitude Measurement Technology Based On The Combination Of Geomagnetism And GPS

With the continuous progress and improvement of national defense science and technology,modern rockets technology are moving towards the development of intelligence and precision guidance.At present,Missile body measurement and control has become an important development direction,real-time accurate measurement of projectile attitude has become the basic technical requirements.In navigation,magnetic detection technology has the characteristics of high stability,no cumulative error.At present,dual-antenna of GPS can offer high-precision attitude angle measurement with short baseline.Based on these two kinds of technology advantage,a scheme of geomagnetic/GPS combination is presented for rocket attitude measurement.In other words,three-axis magnetometer and double GPS antenna combination attitude measurement.Study the magnetometer calibration technology and the method of attitude determination algorithm.And verify its accuracy effect by simulation.Firstly,this paper introduces the development background and research value of projectile body pose measurement technology,analyzes the research status of geomagnetic detection technology and global satellite positioning technologySecondly,the measurement error of three axis magnetic sensor is analyzed and a unified error model is established.The least square calibration method is studied and the calibration scheme is designed.For the ellipsoid calibration method,there propose two hypotheses of that Ell-col and Ell-row.And an iterative method for error correction matrix is designed.Through numerical simulation of five calibration methods,results are shown that the least square method has high precision,and the ellipsoid calibration method is independent,among which the upper triangular ellipsoid method has the best calibration effect.Then,according to the magnetic sensor and dual-antenna of GPS measurement characteristics,design the basic structure of integrated navigation and two kinds of attitude solution methods are deduced:the electronic compass solution algorithm,TRIAD,its improved algorithm,and the optimized vector TRIAD algorithm based on the reconstructed vector.Finally,flight simulation tests were carried out for the rocket.The attitude calculation method was used to solve the rocket’s flight attitude.The results show that the geomagnetic/GPS combined attitude measurement scheme could measure the full attitude angle of the rocket in real time,which realized the complementary advantages of the two technologies.The attitude accuracy of the algorithm with optimization effect is higher than that of the traditional electronic compass and TRIAD algorithm.