基于数据加权融合的wMPS系统定向方法

Transmitter parameter calibration of the workspace measurement and positioning system based on data weighted fusion

为了提高室内空间测量定位系统(wMPS)的定向精度,提出了一种数据加权融合实现wMPS各发射站间定向的新方法。方法引入激光跟踪仪控制场三维坐标约束和wMPS发射站光平面约束,将测量不确定度转化为权重进行优化分配,推导了误差传递函数,将摄影测量中的坐标系转换方法用于单个wMPS发射站与全局坐标系间的坐标转换初值的计算,最终建立数据加权融合的定向数学模型并实现解算。仿真表明,利用本文方法,定向平移量误差在0.09 mm以内,用四元数表示的旋转角误差在2.4"以内。按照本文方法定向后的系统,在8m×5m×4m的范围内进行实验,点位测量精度优于0.21mm,基准尺长比对精度优于0.1mm。实验表明,本文方法与传统的利用已知控制点进行定向的方法相比,定向精度得到了明显提高。

In order to improve the orientation precision of the workspace measurement posit ion system （wMPS）,a new calibration method based on data weighted fusion is prop osed in this paper.The method adds three-dimensional coordinate constraint of laser tracker and light plane constraint of wMPS to obtain a higher orientation precision.The error transfer function is derived .The uncertainty of laser tracker and wMPS is converted into weight to orientate.The DLT algorithm which is usually used in photogrammetry coordinate transformation is used creatively to calculate the ini tial value of the RT from the single wMPS transmitting station coordinate to the global coordinate.The al gorithm is proved effective and is used successfully.Finally the data weighted fusion method is c ompleted .Simulation results show that with this method,error of translation is within 0.09mm and er ror of rotation is within 2.4＂.The experiment is performed in a 8m×5m×4m space with wMPS orientated by this method. The accuracy of point measurement is better than 0.21mm,while the accuracy of r uler length measurement is better than 0.1mm.The results of experiment show that method proposed in this p aper has higher orientation precision compared with traditional orientation method which uses kn own control points.