Determination of Vector Acceleration for Airborne Vector Gravimetry
|School||PLA Information Engineering University|
|Course||Geodesy and Survey Engineering|
|Keywords||Airborne Vector Gravimetry Acceleration Vector Gravity Disturbance Vector Attitude Error SIMS DGPS Orbit Errors Coriolis Acceleration|
Airborne gravimetry is an efficient technique in obtaining the precise and mid-high frequency information of the earth’s gravity field. After the airborne scalar gravimetry system CHAGS (Chinese Airborne Gravimetry System) has been developed successfully and put into field production, it promotes the research on airborne vector gravimetry prominently. The main work is summarized as follows:1. The differential equations of coordinate conversion matrix were derived in detail. The windows lowpass filter was designed and its parameters were determined.2. On the basis of Newton’s second law of motion, the mathematic model was established for airborne vector gravimety, and the error model of gravity disturbance vector was obtained. Then the effects caused by main errors including precise acceleration, Coriolis acceleration, normal gravity, attitude, lever arm corrections, and time synchronization on gravity disturbance vector were investigated and analyzed. The system structure and data processing flowchart for SINS/DGPS airborne vector gravimetry system were described simply.3. The mathematical models of velocity vector and acceleration vector by double-difference were established. The main errors in DGPS that include orbit errors, multipath errors, measurement noise, and the attenuation of position precision were analyzed.4. The precision of the determination of the velocity vector and the acceleration vector under stable and kinetic conditions was analyzed using the Doppler frequency shift method and the phase difference method respectively based on CHAGS observation.