The Design Of Geomagnetic/Gyro Attitude Measurement Combination System

Navigation technology is a comprehensive cutting-edge technology involved withmulti-disciplinary and multi-field, which is the key to realize the precision guided missile.The design of the navigation system not only can track measurement and control of the flyingbody attitude, but also can guarantee the flying body into the expected track to complete thetask. Taking the rotating ammunition attitude measurement system for the engineeringbackground, aiming at the existing problems of mounting complexity, high accuracyinstallation and solving complex, a combination of magnetism, gyro attitude test system isdesigned combined with low cost, miniaturization, high speed real-time computing capacityrequirement. The high-performance digital signal processor TMS320F25338is used in thissystem and the GPS and Kalman filter information fusion technology is also used to furtherimprove the system accuracy.In the beginning, this paper briefly describes the research background and thedevelopment of the inertial navigation system, meanwhile gives a detailed overview of thebasic theory which is used in the attitude measurement system. Then the hardware circuit ofgeomagnetic and gyro attitude measurement system is designed. The system’s signalacquisition unit includes the high overload resistance geomagnetic sensor and high resistanceMEMS gyro inertial devices and high-performance A/D converter. A high-performancedigital signal processor TMS320F25338is used in the system, which realizes navigationcalculating system through the DSP control A/D and provides the hardware conditions for thecomplex algorithm of the navigation system. Finally, on the basis of the above, underlyingcontrol software is designed.This paper studies the selected MEMS gyro through experiment at a high rate turntable,calculates the scale factor, nonlinear, bias, bias stability and bias repeatability. Through theleast squares fitting method, the gyro calibration curve is obtained and analyze the date fromthe calibration curve is analyzed and calculated. This gyro’s accuracy is very high and usingthe MEMS gyro for attitude test is of great value.