| Navigation leads the vehicle to the destination from the origination along specified course within the defined span. To many vehicle that needs navigation system, the high accuracy and the low costs is incompatible, but the balance can be realized by integrating different kinds of navigation system.MEMS is the abbreviation of Micro Electronic Mechanical Systems. MEMS inertial sensors are excellent at the performance of small size, light weight, low cost, low power, high reliability, large measure range and high degree of integration. In this paper, a navigation system integrated by MINS, GPS and Electric Compass is introduced.The structure of Inertial Navigation System, Global Position System and Electrical Compass is discussed, and it put emphasis on their basic theory. Modeling of MEMS inertial sensors and Inertial Measure Unit is illustrated, and the method to obtain the model by experiments is designed. Data of MEMS sensors is simulated, and the algorithm of strap inertial navigation system is described in detail. Kalman Filter is designed to process the information from multi-sensors, which are SINS, GPS and EC. To implement the subject, the hardware is designed first, and the CPU for navigation is FPGA from the first generation of Cyclone. The MEMS sensors ADIS16355 is from Analog Company, the GPS receiver is iTrax02 form Fastrax, and the EC is HMR3000 from Honeywell. Then the soft ware structure is designed on the basis of hardware. The algorithm is realized by programming in C language on theμC/OS-II operation system. And last, experiments are carried out on Tri-Axis Positioning and Rate Table. The results show that the integrated navigation system is better than any of the three subsystems in accuracy and reliability. |
