The Design And Realization Of Control Loop Of Terrestrial Gimbaled INS

Along with the development of inertial technology, the inertial navigation system ofplatform （PINS） has been widely used in navigation, aerospace, aviation and other fields.Compared with the PINS, the strapdown inertial navigation system and combinationnavigation system are obtained rapidly development. However, in the vehicle navigationsystem, due to the cost performance, technology maturity, navigation accuracy and otherreasons, the PINS is still used extensively.This thesis mainly research on the control loop of the PINS, which includs stablizingloop, correction loop, navigation computer system, temperature control loop and the forcefeedback loop, etc. And this paper mainly study on stablizing loop, correction loop andnavigation computer system. Stablizing loop and correction loop work together can makethe navigation system track the geographical coordinate system. Navigation computersystem is not only the man-machine interactive platform of the whole navigation system,but also is the control center, and at the same time controls the correction loop.This thesis researches the structure, model, functional simulation, schematic designand board level debugging of stablizing loop of inertial navigation system. In engineeringfield, the analog method is still used to design the stablizing loop which is relative closely tothe stability and the precision of inertial navigation system. This thesis adopt the classic PIDmode to correct the stablizing loop, in order to improve the adaptive capacity and reduce theresponse time of the system, the Fuzzy-PID controller is introduced to do simulationresearch on the stablizing loop.CycloneIII-EP3C16Q240C8of the company of Altera is adopted to design thenavigation computer. Because it’s better properties in power, volume, speed, real-time, andcost-effective than the traditional single-chip microcomputer. The system allows user to userepeatedly, and it can be done more complex work in the bad environment conditions.Sothis chip is adopted to design the navigation computer system which can increase theoperation speed of the inertial navigation system.On the basis of accomplishment of the computer system design, then the developmenttool of FPGA can be used to design the sine wave excitation signal generator. In addition,axis-angle digital conversion system is designed to measure the shell and the gyroscopespindle deflected angle, which could make the system inversion fastly.Considering the rotation of the earth, in order to make the PINS track the geographic coordinate system, we need to design correction loop, with the help of navigation computer;this correction loop can correct the system without delay, which can enhance the precisionof inertial navigation system.