Development Of Testing System For Inertial Measurement Unit Based On RTX

SINS (strapdown inertial navigation system) has been the latest development trend of INT (inertial navigation technology) in recent years, which is widely used in missile guidance systems because of its advantages. IMU (inertial measurement unit) is the core device of SINS, and the accuracy of its functions is very important for precision-guided missiles. A high-performance real-time test system for the IMU of a missile with SINS is researched and designed in this thesis.Firstly, the overall design is proposed. High performance IPC (Industrial Personal Computer) based on PXI bus is used as hardware platform and IMU measurement board based on PXI and FPGA is developed to complete the test. In order to obtain the real-time performance of test system, real-time extension (RTX) module is added into Windows as software platform according to the comparison and analysis.Secondly, the realization of IMU measurement board is presented in details, including chips selection, hardware circuit design, PCB design and board debugging. And the design of hardware circuit includes PXI bus circuit, FPGA circuit and external auxiliary circuit.Afterward, the software design of test system is specified with 3 parts: driver programmer of IMU measurement board under RTX, communication method between window process and RTX process, application programmer of the test system.Finally, the IMU in a certain missile is tested with the system. The results indicate that the test system achieves the requirements perfectly.The features of this thesis are importing Windows+RTX as software platform, and implementing the IMU measurement board with special functions. The test system developed in the dissertation achieves good real-time performance (1.25ms), high accuracy, easy maintenance, compact structure, and easy expansion.