Application Of FOG SINS Based FPGA

FOG strapdown inertial navigation system which replaced a solid platform withmathematical platform, is a kind of very advanced inertial navigation system. comparedwith the platform inertial navigation system, it has the advantages of small volume, lightweight, low cost, high reliability. therefore, there are many domestic and internationalresearchs about this area. The FOG is applied widely because of its long service life, simplestructure, instantaneous starting, all solid state. This thesis with practical engineering projectas the background, researched the FOG strapdown inertial navigation system, completed thecore board hardware design and software design.The traditional FOG strapdown inertial navigation system board hardware design basedon DSP+FPGA, appeared a large volume, interface communication complex, large powerconsumption and other problems. this paper put forward a new hardware design based onSmartfusionFPGA aimed at the traditional hardware problems.the chip integratedFPGA+ARM. The FPGA is the core to Each hardware unit,completing the FPGA minimumsystem design, SPI, UART, I2C, TIMER, and FPGA are accomplished in FPGA, andachieved pulse acquisition in the FOG. Accelerometer as part of a measurement unit, thedata acquisition is very important, this article aiming at the NV.QA101accelerometercurrent signal designed amplifying circuit, using with high precision24bit AD conversionchip,collecting datas.To make sure the inertial sensor for a given application adaptability, this papercalibrated for the FOG inertial measurement unit, firstly establishing three axis FOG andaccelerometer error model, ideally derived model in various related quantity calculationformula, put forward twelve position method to measure FOG bias and accelerometer bias,scale factor, installation error, the two item coefficients,considering the influence oftemperature, establishing the temperature three order model for the zero bia and installationerror. Using robustfit function in matlab to fit out the coefficients. Finally, through theenvironmental test, verified the error model and the effectiveness of the calibration method.In the process of debugging and testing system, the system worked reliably, realizedthe FOG Strapdown Inertial navigation function, and has good practical engineeringreference and application value.