| The gyroscope is the measuring equipment which sense the angular motion that vehicle relative to the inertial space, it has a extremely widespread application in the aviation, astronautics, the navigation, the weapon as well as other some domains. Along with inertia technical development, The laser-gyro, the optical fiber gyroscope as well as the tiny-silicon gyro is more and more accounted of, But the DTG which have simple structure, cheap cost still held certain superiority, Although its technology already quite mature, some countries still extremely attach importance to its development, Studies mainly emphasis on increases the precision, the dynamic performance, Reduced noise and power dissipation, Realization miniaturization .The Dynamic Tuned Gyroscope which apply in the Strapdown system must work in the closed loop condition through the Rebalance loop. the function of Rebalance loop have two: first, provides to the gyroscope moment the moment electric current, causes its rotor move along with the carrier; Second, carries on the precise quantification of the moment electric current, and provides as the carrier angular motion information to CPU, the precision of rebalance loop affect directly the gyroscope precision, therefore research to the rebalance loop have the extremely vital significance. According to the difference of executes the moment way, it may divide into the analog rebalance loop and the digital rebalance loop. This article design a digital pulse rebalance loop, through the DSP control the A/D to sample the gyro signal, and realize digital PID control, then outputs two PWM to the gyroscope moment.North seeker is one kind of equipment which use to find the north, it uses the gyroscope and accelerometer to sense the component of velocity of the Earth rotation and acceleration of gravity, then calculates the angle between the projection that the reference axial of the carrier in the horizontal and the geographic north direction, namely northerly angle. This article uses the two-position seeking plan, combine the high accuracy and high stable rotate mechanism, it has a short seeking time, simultaneously may eliminate the constant drifting of the gyroscope, and the gyroscope stochastic drifting influence is also small.It use TI Corporation TMS320F2812 DSP and XILINX Corporation Series FPGA as the hardware electric circuit core to digitized the Rebalance Loop of DTG and the North Seeker, and it also has designed the DSP related hardware electric circuit as well as its software procedure.Finally, it gave the test data of the North Seeker, including duplication, high temperature, low temperature and so on, through these experimental, we have get that the system performance has improve several times than the analog system, its proof shows the accurate of the system hardware and software algorithm as well as digitized system control superiority. |
