基于物体影长数据的定位方法研究

Positioning method based on length of object's shadow

根据物体在太阳光下的影子变化数据来判断其所在的地点和日期,是一项具有现实意义的研究。通过分析时角、赤纬角及当地的经纬度与物体影长的物理学关系,将地点的空间定位问题转化为数学上的优化问题并建立模型进行求解。在日期已知时,利用确定性的两阶段空间搜索算法进行模型求解;在日期未知时,改进模型,利用细菌觅食优化算法(bacterial foraging optimization,BFO)进行求解。经检验,两种定位方法的效果均良好,可具体应用于解决现实生活中的地点定位。

It is a meaningful research topic to find out w hen and w here an object is by analyzing the trace data of its shadow under the sun .T he spatial localization problem can be converted to an optimization issue under appropriate framework ,and be solved by building a mathematical model ,which is based on the relationship between shadow’s length and such factors as hour angle ,declination angle ,longitude and latitude .Besides ,a two‐phase space search algorithm can be implemented to solve the model when given priori information about date ;otherwise ,the model can be rectified and then be figured out by utilizing the bacterial foraging optimization . The performance of these methods are well‐behaved ,and can be used in real‐world applications .