Study On The Attitude Measurement System Based On Variable Parameters Complementary Filter

Attitude angle, as an important information, is indispensable in navigation, it is also an important parameter to ensure carrier safe operation, and the carrier attitude measurement has attracted much attention in the aerospace, aviation, marine, military and industrial fields. Aiming at the problem that the multi-sensor complex complementary filter could not adapt to the motion state change with simple cut-off frequency method in the multi-sensor attitude measurement system, and the magnetic field disturbance detection relies on the gyroscope, a variable parameters complementary filter algorithm is designed, moreover, a multi-sensor attitude measurement system is constructed, which verified that the algorithm could realize the multi-sensor data fusion with high precision, and could reduce effectively the influence of the motion state change and the magnetic field disturbance. The main research content is presented as follows:1. Analyzing the current development situation of attitude measurement system, and aiming at the problem in the MEMS multi-sensor integrated attitude measurement system, a variable parameters complementary filter design ideas is put forward.2. The basic coordinate system and the mathematical symbols are introduced, moreover, the coordinate system transformation matrix, the gyro attitude solving with Quaternion, the accelerometer attitude solving and electronic compass attitude solving are studied.3. The noise of MEMS gyro, MEMS accelerometer and electronic compass are analyzed in frequency domain, and, based on the noise frequency complementary characteristic, a complementary filter is constructed. The motion state and the magnetic field are monitored with the accelerometer and the electronic compass, and the variable parameters are analyzed and designed.4. The attitude measurement system hardware design. The system hardware includes the sensor module, the control & operation module, the communication module, and the power module. Based on the hardware platform, with the MicroBlaze as the core, the system on chip is constructed in the FPGA chip.5. The attitude measurement system software design. The system software includes the data acquisition module, the attitude solving module, the data transmission module, and the host computer software design.6. The experimental verification of variable parameters complementary filter. The complementary filter output and the AHRS measurement result are compared in the attitude measurement experiment, that verifies the effectiveness of the complementary filter, and the complementary filter could maintain the high accuracy of the system. In the variable parameters experiment, it shows that the variable parameters method could reduce effectively the influence of the motion state change and the magnetic field disturbance, and improve the system anti-interference ability.