The technology of visible light positioning (VLP) has the advantages of low cost, high precision, no electromagnetic interference, convenient deployment, and the advantage of taking into account both communication positioning and lighting which makes this technology has potentially useful application prospects in the field of indoor positioning. In this paper, two indoor positioning methods based on visible light communication (VLC) called imaging and non-imaging method are summarized, meanwhile, their key technologies, research development, applications and trend are analyzed and discussed. A VLP light source matching identification method based on autocorrelation sequence is proposed, what's more, a method of constructing a positioning system based on the common imaging sensor and rectangular flat-panel light source is introduced. Finally, the research and development direction of indoor VLP technology is prospected.

基于可见光通信与矩形平板LED光源,提出一种室内视觉高精度定位方法,为室内移动机器人提供一种精度高、速度快、成本低的室内定位系统方案.该方法首先利用可见光通信技术获取LED光源的坐标信息,利用单个视觉传感器对矩形LED光源进行成像测量,同时使用IMU传感器记录成像测量的倾斜姿态角辅助单像空间后方交会解算;然后设计并仿真分析了4种单像空间后方交会算法在高精度倾斜姿态角辅助下定位误差随角点提取误差的变化情况,并研制了定位模块进行验证.测试结果表明,当采用800像素×600像素分辨率的图像和0.58 m×0.26 m的矩形平板LED光源时,定位模块可在2 m×2 m×2.5 m室内环境中实现cm级移动定位,并且定位频率大于30 Hz;在IMU姿态辅助下,定位模块可以实现优于5 cm的定位精度和优于1°的定向纠正;该方法还能为室内移动机器人提供厘米级定位导航服务.

为了满足地下工程中精密坐标传递的需求,设计了一种高精度三维导线测量及数据处理方法.受三联脚架法的启发,提出了利用三联全站仪法构建精密三维导线的思路.利用U型卡扣将球棱镜靶座固联到全站仪提手上,标定出球棱镜中心与仪器中心的空间关系,据此改化观测值;以仪器中心之间的连线构成三维导线,避免了人工测量仪器高和棱镜高带来的误差.设计了一种实用的铅垂线不平行性改正模型,利用Helmert方差分量估计合理确定了多类观测值的权,使三维导线平差过程更为严密.以某隧道工程测量为实例,利用三联全站仪法建立了由15条导线边构成的三维闭合导线.与传统三维导线平差结果相比,经铅垂线不平行性改正和方差分量估计后,单位权中误差明显减小,导线点坐标精度明显提高,精度优于±0.5 mm;用数字工业摄影测量系统进行验证,点位外符合精度达±0.32 mm.通过采取各项有效技术措施,所提方法经受了短边、大垂直角等严峻条件的考验,有推广应用价值.

In order to improve the correctness and robustness of existing stable points selection methods of reference network when there are many unstable points, a robust stable points selection method using squared Msplit similarity transformation is proposed. This method still works when the number of unstable points is close to or even more than the number of stable points. Firstly, the reference points are divided into two groups with square Msplit estimation in the process of calculating the similar transformation parameters of two measurement epochs. Then, by taking the group with more points as stable one, the stable points group is divided into two groups continually until the similarity transformation parameters of the two groups have little difference. Finally, deformation analysis is conducted with the similarity transformation parameters which are calculated with the final stable points group. Experiments are carried out to compare the effect of traditional S transformation, robust S transformation and the proposed method under the condition that there exists some points with large deformation in reference network or the number of unstable points is close to or even more than the number of stable points. And the experimental results show that the proposed method has the highest correctness rate of stable points determination, gets the smallest difference between the calculated deformation and the simulated deformation, and gains the smallest root mean square of coordinates difference of the stable points group between two measurement epochs, which means that the result of the proposed method can correctly reveal the deformation of control points.

针对传统天线测量数据处理中粗差剔除和定权不合理问题,提出了一种结合粗差剔除和一次范数最小法定权的天线反射面多仰角测量数据处理方法.首先,根据反射面自重变形的特点,通过构造统计量对粗差点予以剔除,提高了测量数据的可靠性;其次,顾及测量点的变形特点,引入了抗差估计中的一次范数最小法对不同变形点进行定权,解决了等权最小二乘拟合的"虚假面型"问题.经过某口径13m天线反射面测量数据的实例计算,对比其他方法,新方法拟合结果能够合理、准确地反映出反射面的实际变形偏差,更适用于天线反射面自重变形数据的处理.

提出一种基于可见光通信与双目视觉测量的高精度室内定位方法,旨在为室内移动机器人提供一种精度高、成本低、不易受干扰的室内定位方案.该方法利用双目视觉传感器对LED光源进行成像测量,利用惯性测量单元传感器记录成像测量的三维姿态角,并通过可见光通信技术获取LED光源的坐标信息,最终计算双目视觉传感器相对于LED光源的三维坐标.根据该方法研制了一款基于可见光通信与成像的定位模块,该模块可以利用单个或两个LED光源进行成像定位.当定位模块采用1 280×720分辨率的图像时,在2 m×2 m×3 m室内环境中可实现厘米级移动定位,定位频率大于5 Hz;当利用两个相距60 cm的LED光源进行定位时,在三维方向上的定位误差均小于5 cm,同时能够提供小于1.4°的定向纠正.该方法可以为室内移动机器人提供厘米级定位导航服务.

With regard to the inferior techniques and low accuracy of phase center calibration of an antenna array,this paper proposes a new calibration method considering the actual antenna pointing by introducing a precise engineering surveying technique to measure the real state of antennas. First,an industrial photogrammetric system is utilized to obtain the coordinates of points on antenna panels in different postures,and the actual pointing of the mechanical axis is obtained via least-squares fitting.Then,based on this,the coordinates of antenna rotation center are obtained by seeking the intersection of mechanical axes via using the matrix method. Finally,the mechanical axis in arbitrary postures is estimated based on the inverse-angle weighting interpolation method,and the reliable phase center is obtained by moving a fixed length from the projective center along the mechanical axis. An uplink antenna array including three 3 m antennas is taken as experimental object,and all photogrammetric coordinate systems are unified by the engineering control network,with each antenna phase center precisely calibrated via the proposed method. The results of electrical signal synthesis indicate that this method can effectively overcome the influence of gravity deformation and mechanical installation error,and enhance the synthetic signal magnitude of the uplink antenna array.

针对大尺寸物体位姿实时精密测量的需求,基于单像空间后方交会原理,设计一种基于单相片的位姿测量方法.位姿重复测量实验表明,在6 m范围内,文中方法位置重复测量精度优于0.021 m m,角度重复测量精度优于0.0036°.与激光跟踪仪测量结果的公共点转换实验表明,文中方法位置测量精度优于0.060 m m,角度测量精度优于0.0052°.文中方法操作简单,设备成本低,适用性好,能实时、高精度测量大尺寸物体的位姿.

针对传统天线旋转中心测量时,俯仰轴生成方式不严密对其精度和可靠性产生不利影响的问题,提出了俯仰轴相交和球拟合两种新的旋转中心测量方法.对不同方位下标志点绕俯仰轴的运动轨迹进行圆拟合,得到含有方位信息的俯仰轴,多条俯仰轴求交点作为旋转中心,称之为俯仰轴相交法,较传统方法可靠性更高.对标志点的运动轨迹进行球拟合,取所有球心的均值作为旋转中心,称之为球拟合法,避免了圆拟合及求交点的过程,方法更为严密.以3台φ3 m上行阵天线为实验对象,应用全站仪和工业摄影测量技术获取标志点在规划姿态下的坐标,采用两种新方法处理观测数据,均得到了内符合精度达亚毫米级的旋转中心.

数字工业摄影测量中,十参数模型是目前应用最广泛的相机畸变模型,但也存在过度参数化问题.相机标定以像点坐标为观测值,当标定模型同时受到复共线和观测异常的影响时,相机标定结果也会受到影响.为提高相机标定精度,提出基于抗差岭估计的相机标定方法,该方法不仅可以改善模型中由于过度参数化导致的复共线问题,而且可以有效抵制观测值异常的影响,提高相机参数求解精度.

In digital industrial photogrammetry, the image point coordinates obtained from the different photos taken by the camera are regarded as the observations of the equal precision. The weights of the observations are defined as the unit weights in the adjustment process. The self-calibration bundle adjustment method can effectively com-pensate system error, but there are still inevitable errors and random errors in the measurement process. In order to further improve the accuracy of the calculation results of digital industrial photogrammetry adjustment, taking into account the robust estimation with making full use of effective information, restricting the use of useful information and eliminating harmful information, the self-calibration bundle adjustment method is modified and a new method based on IGG3 is proposed in this paper. The common point conversion experiment and repeated measurement ex-periment are carried out to evaluate the inside precision and outside precision. The experimental results show that the modified method is more accurate than the original method.

For the urgent demand for mould scribed line detection in the mould industry,single-camera position and orientation measurement system based on measuring pen is used in scribed line detection.Based on the principle of single space resection,the relationship between the measuring pen coordinate system and the world coordinate system is established.The coordinates of the tip of the measuring pen which touches the scribed line are calculated using three-dimensional coordinate transformation.The detection precision is obtained comparing all measurement points with CAD model.The method is flexible and convenient,and has high measuring precision.Practical engineering results demonstrate that the mean square deviation is less than 0.5 mm in the range of 3 m,which can completely satisfy the demand for the scribed line detection in large size measurement.

提出了一种精确测定数码相机投影中心位置的方法,详细介绍了其工作原理和实施方法.利用MetroIn经纬仪三坐标测量系统和MetroIn-DPM数字工业摄影测量系统的高精度测量特点,提高了控制点坐标测量精度、控制点标志中心像点坐标量测精度并实现了相机的高精度标校.在一个试验里完成了高精度相机标校和投影中心位置精确测定,实现的投影中心位置测定精度优于5mm.

The appropriate mathematical model is chosen to reduce the effects on the accuracy by comparing the differences of the displacement distribution before and after applying the glasses. The experiment shows that the protective cover glass of camera has an influence on the measurement accuracy, and the biggest variation of the coordinate of the image point is approximately 5 micrometers and the distribution of the variation consists with the radial distortion. Finally, the influence could be replaced by a radial distortion model and the experiment shows that this method can effectively reduce the effects of the glass on the measurement accuracy.

The installation measurement of a 9 m×36 m antenna is introduced in the paper.Both the direction and planeare adjus?ted according to the measurement data of GPS,total station instrument,double?theodolite and industrial photogrammetry.The geodetic azimuth of the antenna is acquired through GPS.The construction control network is built by total station instrument.The frame and pan?els of the antenna are laid out through double?theodolite system.Industrial photogrammetry system is used to adjust the panels of the an?tenna precisely.The final accuracies of the direction and plane of the antenna are 0. 016° and 0. 304 mm respectively, meeting the design requirements.

针对双相机数字工业摄影测量中的人工标志点自动匹配问题,设计了一种基于相对关系不变性的图像匹配算法,根据平缓过渡曲面上相邻点间相对关系在两张像片上一致的原理,解决了两张像片的标志点自动匹配问题.3组实验表明,该算法匹配正确率高,匹配速度快,能够满足动态测量数据处理的需求.

The multi window recognition algorithm was proposed after research on the problem of moving target rec-ognition method in single camera online vision position and orientation measurement. The algorithm processed the next frame using the measurement results of last frame as a priori information to increase computing speed and avoi-ded the problems of match of target number. It also provided the calculation formula of the search-window threshold value. A new direct recognition algorithm without start-pixel searching was presented based on Affine Transform. The results of the experiment showed that these two methods can promote efficiency of target recognition without de-pressing the accuracy. It proved to be useful in practice.

针对数字工业测量相机检校问题,在10参数相机畸变模型的基础上,提出一种基于有限元模型的二次检校方法,利用10参数模型补偿相机可预见性畸变差,剩余的不可预见性畸变差则利用有限元模型进行二次补偿。通过对INCA3量测型相机和CanonEOS 5D Mark Ⅱ、Nikon D2H非量测型相机的检校试验发现,量测型相机的机械结构稳定、成像噪声低、测量精度提高显著,但非量测型相机的精度提高不明显。

The Australian SKA Pathfinder ratio telescope (ASKAP) comprises an array of up to 45 dish antennas with diameter of 12 meters. ASKAP is situated at Australia's candidate site for the International Square Kilometre Array telescope in Western Australia. It is intended to be a fully-functional radio telescope, with a science case based on its wide-field-of-view capabilities at centimeter wavelengths. The paper reports the photogrammetric measurement of the first ASKAP antenna reflector surface. Deformation of the reflector surface was measured with photogrammetric system V-STARS at six different elevation and polarization angles. The maximum RMS of orthogonal distance residuals from the best-fit paraboloid is 0.58mm, less than the design accuracy of 1mm.