彩色大面阵航空测绘相机前向像移补偿分析及误差纠正

Analysis of Forward Image Displacement Compensation and Error Correction for Area Scan Color CCD Airborne Mapping Camera

为了提高彩色大面阵航空测绘相机的成像分辨率和测绘精度,对其前向像移补偿的可行性进行了分析,并设计了前向像移补偿机构。根据航空成像的中心投影模型,研究了前向像移补偿下航空测绘相机内、外方位元素的变化对成像过程的影响,证明了前向像移补偿的可行性;设计了一套基于等径共轭凸轮机构的前向像移补偿机构,并分析了各种误差因素对测绘精度的影响;提出了基于仿射变换的误差纠正方法。实验结果表明,提出的前向像移补偿方法正确,机构引入误差的纠正精度可以达到0.001mm。

A forward image displacement compensation device is designed and its feasibility for area scan color CCD airborne mapping camera is researched to improve the ground pixel resolution and the mapping accuracy.The effect of intrinsic and extrinsic parameters on image point during forward image displacement compensation is emphatically analyzed based on imaging relation of central projection,and the feasibility of the forward image displacement compensation for airborne mapping camera is verified.The compensation device,which is based on constant-diameter conjugate cam is designed and factors′ affecting the accuracy of aerial photogrammetry are studied.The rectified method is proposed by using affine transformation.Experimental results show that the rectified accuracy is 0.001 mm,and the proposed method of forward image displacement compensation is correct.