摘要
为了提高双CCD摄影测量系统对大口径且具有反射表面物体的近场三维测量精度 ,提出用最小二乘广义逆法解决成像系统的非线性问题 ,分析比较了用最小二乘广义逆法和Levenberg -Marquart2种方法解决成像系统的非线性问题 ,并采用投影生成特征点法 ,对圆抛物面形卫星天线进行测量 ,重构其面形。实验表明 ,该系统操作简单、实用性强 ,消除系统的非线性问题后 ,测量精度提高 2 0 % ,测得面形与理论面形相当吻合 ,可用于大型物体的面形测量。针对被测物具体条件 ,选择合适的算法消除系统的非线性问题及合适的光照条件有助于提高系统性能及其实用性。
In order to reduce the mean error of double CCD closed photogrammetric system used in measuring large caliber object with reflective surface , the architecture and principle of a visual measurement system based on photogrammetry are described——the method of general reversion of least square. The method of general reversion of least square and that of Levenberg Maraquart are compared in solving nonlinear system problem,and the former is used to compensate the aberrance of lens . The projected spots is presented as latent spots. An antenna which is paraboloid is measured and reconstructed.Experimental result shows that the system can meet the need of the 3 D measurement of large object. After the aberrance of lens is compensated,the mean error is deduced to 80%.In the light of actural project measured,a suitable method which can solve the nonliear problem under proper light circumstances will help to enhance the system function and practicality.
出处
《北京机械工业学院学报》
2001年第1期36-39,49,共5页
Journal of Beijing Institute of Machinery
关键词
摄影测量
非线性方程组
最小二乘广义逆法
特征点
photogrammetry
nonlinear equations
general reversion of least square
latent spots
