Reasearch On Testing Technique For Reliability Of Hardare Platform In Fiber-Optic Trap-Down System

The FOG Strapdown Inertial Navigation System is an important trend in the development of marine navigation system. This paper researched on the application of high-performance floating-point digital signal processor(DSP) in SINS. And a new scheme to design the strapdown information processing hardware platform, which is based on the TMS320C6713B, was proposed.The application of fiber-optic gyroscope trap-down inertial navigation system has a wide range in both military and civil areas because of its increasing precision and availability.Researches on techniques for trap-down inertial navigation system have been a worldwide topic. However, there is a huge gap between domestic manufacture level of fiber trap-down system and advanced world standard level, and the problem are mainly reflected on the reliability and precision of ours which cannot reach the advanced standard. Especially in military application field, there are extremely high standards and tough condition tests including temperature, magnetic field, mechanical vibration and some other kinds of tests set before for the fiber strap-down system which was for the military application purpose. This dissertation contains some basic research work for the reliability test of fiber trap-down system, and acts as fundament for practical application and production in near future.Firstly, the basic principle of fiber-optic gyroscope was presented, then discussed the principle of trap-down navigation system and its mathematic model particularly. Employed DSP and FPGA techniques to achieve the information processing hardware for fiber trap-down system, the hardware board can acquire the data from temperature block, gyro block and accelerometer block and store them into the memory or send them to the computer. Also, some research was focused on the method of storing data, concrete testing plan was designed and programs for interruption, initialization and testing the memories such as RAM, external FLASH and AT24C02 were given. Analyzed reliability characteristics, method of reliability information collection, effectiveness of reliability model and probability distribution of time intervals where faults might happen unexpectedly. According to the data of faults record of some kind of fiber trap-down system made domestically, found that the probability distribution obeys Weibull distribution and derived the values of mean time periods between two faults, and between two maintenance and inherency useable degree, respectively.Totally designed a testing system for the fiber trap-down system. To send regular and effective testing signals through the testing system, designed signal generator based on the principle of DDS by using VHDL and FPGA, and simulated the main functions corresponding to those basic blocks in the signal generator through MODELSIM as well. In order to acquire the data of user's tracking record and various reliability test results and to estimate reliability characteristics effectively, analyzed and planed the testing scheme, polling block and initialization of testing condition for the reliability information management system and analysis system in fiber trap-down system in details. Finally, derived some suggestions of improvement for the system based on work mentioned above and shortcomings which have been encountered.