【摘要】 采用直流力矩电动机和数字控制技术,拖动一个装有挠性陀螺、石英挠性加表的转盘连续转动四个位置,测量每个位置上陀螺和加速度计的输出,从而计算出定位面和北向的夹角。推导了北向角计算公式、方位角增量计算公式,分析了系统组成,给出了原理框图。为了缩短寻北时间,克服地基抖动和风扰等影响,采用数字滤波、平稳过程建模、小波滤波、Kalman滤波等技术对陀螺信号进行预处理。试验证明:求平均和经典数字滤波可减小陀螺数据方差10倍左右,Kalman滤波可以减小30倍。目前该系统样机已经研制成功,控制器和计算平台采用PC104,显示器为可在野外使用的EL屏,4×4小键盘采用不锈钢防水设计,具有抗低温能力,系统内置GPS接受机、蓄电池,可实现野外定位定向自动化。测试表明:样机定向精度优于2 mil,定向时间小于2.5 min。更多还原

【Abstract】 Digital motor control technology was employed to drive a turntable to four locations.On the turntable a dynamically tuned gyroscope and a quartz accelerometer were fixed.The outputs of the gyroscope and the accelerometer were tested on every location,and then the azimuth angle could be calculated.The principle and formulas were given.Some digital signal processing methods,such as IIR filter,AR(2) compensation model,wavelet filter and Kalman filter,were used to improve the data accuracy.The test data suggest that all of those methods could reduce errors,but Kalman filter is the best method,which could increase the precision by about 30 times.The system prototype has been successfully developed,which include an embedded computer PC104,a 4×4 stainless steel keyboard,an embedded GPS receiver and a storage battery.The tests show that the north orientation error of the system is less than 2 mil(σ) and the orienting time is just 2.5 min.更多还原