两次步进预置北限幅设计

Design of twice stepped limiting program by presetting on north

针对陀螺经纬仪存在限幅效率低的工程问题,设计了一种两次步进预置北限幅方案。介绍了传统步进限幅方法原理,分析了陀螺摆动平衡位与静摆零位的关系。将传统步进限幅法中的静摆零位跟踪更改为平衡位跟踪,通过两次步进使陀螺主轴摆动迅速限幅并以小摆角在真北附近运动。推导了两次步进转动角度及时刻的数学公式,分析了误差因素,并针对不同的摆幅和悬挂带扭转系数与陀螺力矩系数的比值进行了仿真运算。采用该方法改进了一个陀螺经纬仪的限幅,实验结果表明,该方法能在一个陀螺不跟踪摆动周期内完成限幅,限幅精度达到1′。提出的限幅方法保留了传统步进限幅法不需要增加系统硬件的优点;提高了限幅效率,满足工程应用对寻北时间和精度的要求。

A twice stepped limiting program by presetting on north was designed to improve the efficiency of limiting process of a gyrotheodolite.The principle of traditional stepped limiting was introduced,and the relationship of the swing balance and the zero position of gyrotheodolite was analyzed.Then,the traditional program of zero position following was redesigned to a balance position following now,so that the gyro could quickly limit the swing of the gyro and allow it to campaign with a small swing near north through stepping twice.The mathematical formulas for two stepping angles and time were derived,the error factors on the limiting effect were analyzed and the different swing ranges and the coefficient ratios of suspensory torsions to gyro torques were simulated.Finally,the program was applied to a pendulous gyroscope.The theory and experiment results show that the limiting is implemented in an un-following gyro precession circle with a limiting precision of 1′.The program proposed reaches the precision index and time demand of north-finding without adding any software,and improves the efficiency of limiting.