Research On Initialalignment And Orbiting Correction Method

The navigation system of vehicle is very important and it is the premise ofOrbit Maneuvering, release and earth observation. So the navigation system ofvehicle must be a high-accuracy position system. The navigation accuracy isdecided by alignment accuracy and calibration accuracy, therefore, alignment ofINS must be accomplish before takeoff. This dissertation aims at solving problemof initial alignment in quick-launch situation, researching initial alignment onstationary base and orbiting alignment using auxiliary information.Specific to different alignment method, this essay defines navigationcoordinate systems, builds up models of disturbance, dynamics and kinematics.Then the dissertation analogs output of gyroscope and accelerometer, and designstrajectory of ascent and orbit.The equations arranging of INS is based on analytical INS’s error. Thendissertation deduces error propagation function of attitude, station and velocity.Specific to aircraft structures and rocket features of launching environment,initial alignment of INS is researched. The method to calculation initial attitudematrix is given. By formula derivation of misalignment angles and INS’s output,initial alignment scheme is presented. Then Kalman equation is established andinitial alignment workflow is given.In order to meet the requirements of high-accuracy navigation, errorcharacteristics of GNSS and CNS are analyzed. Alignment principle of usingGNSS and CNS is researching.With the purpose of improving dynamics and reliability of navigation, andmeeting the needs of smooth handoff, the dissertation presents a new adaptivefault-tolerant filter having the functions of smooth handoff and adaptiveadjustment. This new method can improve the dynamics and adaptation in thecomplex environment.At last, basing on initial alignment programs the project operation ofMATLAB, the dissertation conducts simulations by setting the parameters. Theinitial alignment programs are validated.