基于变量控制的太阳影子定位

Solar Shadow Location Based on Variable Control

太阳影子定位技术通过观察物体的影子变化来确定日期时间和物体所在的地理位置。建立影长与各参数的数学模型,研究影长分别随其变化规律,采用控制变量法,利用已建立的数学模型分别求解出影长随相应参数的变化关系式,并绘制曲线寻找规律。根据已有数据拟合相应曲线变化,求得影长最小值处所对应的北京时间为12:36,根据两地的时差为36分钟求得影子所在地的经度为110°E。以太阳方位角和实际测量方位角的误差为切入点,利用最小二乘法推算更精确的纬度范围,并进行迭代确定出最优解为19.50°N和19.68°N。

Solar shadow location technology determines the date,time and location of objects by observing their shadow changes.Mathematical models of shadow length and each parameter are established to study the law of shadow length changing with its parameters.Using the control variable method,the relationship between shadow length and corresponding parameters is solved by the established mathematical model,and the curve is drawn to find the law.According to the existing data fitting the corresponding curve changes,the Beijing time corresponding to the minimum shadow length is 12:36,and the longitude of the shadow location is 110°E according to the time difference between the two places is 36 minutes.Taking the error of solar azimuth and actual azimuth as the breakthrough point,the more accurate latitude range is calculated by least square method,and the optimal solution is 19.50°N and 19.68°N by iteration.