光学精密工程
光學精密工程
광학정밀공정
OPTICS AND PRECISION ENGINEERING
2010年
3期
685-691
,共7页
机器视觉%姿态求解%圆%二义性%角度约束%误差分析
機器視覺%姿態求解%圓%二義性%角度約束%誤差分析
궤기시각%자태구해%원%이의성%각도약속%오차분석
machine vision%pose estimation%circle%duality%angular constraint%error analysis
为了消除视觉测量中单个圆姿态识别中存在二义性的问题,提出了一种基于空间角度约束消除二义性的方法,并且对姿态求解算法进行了误差分析,为准确进行姿态估算给出了指导性的实验结果.在摄像机已标定的前提下,根据圆特征在图像上的投影椭圆曲线确定了圆心位置和圆平面姿态参数,计算结果存在二义性;利用欧式空间中的角度不变量,识别出圆平面的真实姿态参数,同时确定圆心的真实位置;最后,根据误差传播理论对基于单圆特征的位姿估计算法进行了精度分析.实验结果表明,圆平面姿态角的测量绝对误差在0.2°以内,圆心的定位误差为0.5%,根据圆平面的位姿参数计算的共面直线的距离误差为0.8%.该方法能够准确地识别圆平面的位置和姿态,计算过程简单,结果稳定可靠且具有较高的精度.
為瞭消除視覺測量中單箇圓姿態識彆中存在二義性的問題,提齣瞭一種基于空間角度約束消除二義性的方法,併且對姿態求解算法進行瞭誤差分析,為準確進行姿態估算給齣瞭指導性的實驗結果.在攝像機已標定的前提下,根據圓特徵在圖像上的投影橢圓麯線確定瞭圓心位置和圓平麵姿態參數,計算結果存在二義性;利用歐式空間中的角度不變量,識彆齣圓平麵的真實姿態參數,同時確定圓心的真實位置;最後,根據誤差傳播理論對基于單圓特徵的位姿估計算法進行瞭精度分析.實驗結果錶明,圓平麵姿態角的測量絕對誤差在0.2°以內,圓心的定位誤差為0.5%,根據圓平麵的位姿參數計算的共麵直線的距離誤差為0.8%.該方法能夠準確地識彆圓平麵的位置和姿態,計算過程簡單,結果穩定可靠且具有較高的精度.
위료소제시각측량중단개원자태식별중존재이의성적문제,제출료일충기우공간각도약속소제이의성적방법,병차대자태구해산법진행료오차분석,위준학진행자태고산급출료지도성적실험결과.재섭상궤이표정적전제하,근거원특정재도상상적투영타원곡선학정료원심위치화원평면자태삼수,계산결과존재이의성;이용구식공간중적각도불변량,식별출원평면적진실자태삼수,동시학정원심적진실위치;최후,근거오차전파이론대기우단원특정적위자고계산법진행료정도분석.실험결과표명,원평면자태각적측량절대오차재0.2°이내,원심적정위오차위0.5%,근거원평면적위자삼수계산적공면직선적거리오차위0.8%.해방법능구준학지식별원평면적위치화자태,계산과정간단,결과은정가고차구유교고적정도.
In order to solve the duality problem in pose estimation of a single circle in machine vision, an approach based on Euclidean angular constraint is presented to identify the unique pose result. The accuracy of pose estimation is analyzed, which provides constructive suggestions on achieving accurate pose estimation of circles based on experimental results. The pose of single circle is recovered from its projection in an image with a calibrated camera, though the result is ambiguous, only two possible results exist. Then, the unique pose is identified based on the Euclidean angular invariant. Finally, the accuracy of pose estimation is analyzed based on the theory of error propagation. Experimental results indicate that the absolute error of pose angle of the circle plane and the relative error of position determination are within 0.2°and 0.5% m respectively,and the absolute error of reconstructed distance between the two lines is within 0.8%. These results show that the approach can identify correctively poses and positions of circle planes and can offer a high measuring accuracy and reliable results by a simple computing process.