Results from a Precise Photogrammetric Densification of Urban Control Network

1982 ◽  
Vol 36 (2) ◽  
pp. 165-172
Author(s):  
S. F. EL-HAKIM

Adjustment of a photogrammetric block located in the city of Sudbury, Ontario, demonstrates that an accuracy of 2 cm in planimetric coordinates can be achieved using a minimum number of control points if additional constraints in the form of observed spatial distances are combined with the photogrammetric mathematical model to reduce the control point requirement. This accuracy has been estimated by error ellipsoids of the adjusted ground coordinates, and by independent field checking. The data have also been used to compare different mathematical functions for the compensation of systematic errors in the method of bundle adjustment with self-calibration.

2017 ◽  
Vol 921 (3) ◽  
pp. 43-47
Author(s):  
Yu.I. Golovanev

The article deals with the fact, that the state or special geodetic networks points identified on the aerial photographs, control network and aerial photographs field control surveys points including contour points with coordinates taken from the topographic map of larger scale and defined when creating topographic maps can be used for exterior orientation of photogrammetric networks during the implementation of works on topographic maps revision. Besides planimetric points of the map that has been revising can also be used. The ground control point (reference point) coordinates are not of equal accuracy, as their values were got from the sources that have different plane coordinates accuracy. This fact has a significant influence on the point coordinates planimetric position of the route photogrammetric network that is developed. There is some information in the article about the control points unequal accuracy influence on the point planimetric position of the route photogrammetric network. This fact occurs when part of control points was obtained by means of accurate surveying methods but other control points plane coordinates due to their unavailability have to be obtained from the topographic map. The results of the experiment are given as evidence.


Author(s):  
K. Di ◽  
B. Liu ◽  
M. Peng ◽  
X. Xin ◽  
M. Jia ◽  
...  

A lunar global control network provides geodetic datum and control points for mapping of the lunar surface. The widely used Unified Lunar Control Network 2005 (ULCN2005) was built based on a combined photogrammetric solution of Clementine images acquired in 1994 and earlier photographic data. In this research, we propose an initiative for construction of a new-generation lunar global control network using multi-mission data newly acquired in the 21<sup>st</sup> century, which have much better resolution and precision than the old data acquired in the last century. The new control network will be based on a combined photogrammetric solution of an extended global image and laser altimetry network. The five lunar laser ranging retro-reflectors, which can be identified in LROC NAC images and have cm level 3D position accuracy, will be used as absolute control points in the least squares photogrammetric adjustment. Recently, a new radio total phase ranging method has been developed and used for high-precision positioning of Chang’e-3 lander; this shall offer a new absolute control point. Systematic methods and key techniques will be developed or enhanced, including rigorous and generic geometric modeling of orbital images, multi-scale feature extraction and matching among heterogeneous multi-mission remote sensing data, optimal selection of images at areas of multiple image coverages, and large-scale adjustment computation, etc. Based on the high-resolution new datasets and developed new techniques, the new generation of global control network is expected to have much higher accuracy and point density than the ULCN2005.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jianying Yuan ◽  
Qiong Wang ◽  
Xiaoliang Jiang ◽  
Bailin Li

The multiview 3D data registration precision will decrease with the increasing number of registrations when measuring a large scale object using structured light scanning. In this paper, we propose a high-precision registration method based on multiple view geometry theory in order to solve this problem. First, a multiview network is constructed during the scanning process. The bundle adjustment method from digital close range photogrammetry is used to optimize the multiview network to obtain high-precision global control points. After that, the 3D data under each local coordinate of each scan are registered with the global control points. The method overcomes the error accumulation in the traditional registration process and reduces the time consumption of the following 3D data global optimization. The multiview 3D scan registration precision and efficiency are increased. Experiments verify the effectiveness of the proposed algorithm.


2020 ◽  
Vol 206 ◽  
pp. 03025
Author(s):  
Junze Wang ◽  
Maohua Yao ◽  
Wenting Zhou ◽  
Xiangping Chen

In this paper, 24 C-level control points under different terrain conditions were selected to be the testing points. The binary-satellite system (GPS+GLONASS) and the triple-satellite system with BeiDou Navigation Satellite System (BDS) (BDS+GPS+GLONASS) were adopted for static measurement; and the observation data from BeiDou Ground-based Augumentation System (GBAS) base stations in Guangxi were collected for solution. By comparing the residuals of GPS tri-dimensional baseline vectors and the internal accord accuracy of each control point under the binary and triple-satellite systems, the effect of data collected by different satellite systems under different terrain conditions on measurement accuracy was studied. According to the results, (1) the triple-satellite system with BDS showed more stable measurement accuracy; (2) in plane, the two systems were of equivalent measurement accuracy in mountainous and flat areas; in elevation, the triple-satellite system showed higher and more stable measurement accuracy.


Author(s):  
M. V. Peppa ◽  
J. P. Mills ◽  
P. Moore ◽  
P. E. Miller ◽  
J. E. Chambers

Landslides are hazardous events with often disastrous consequences. Monitoring landslides with observations of high spatio-temporal resolution can help mitigate such hazards. Mini unmanned aerial vehicles (UAVs) complemented by structure-from-motion (SfM) photogrammetry and modern per-pixel image matching algorithms can deliver a time-series of landslide elevation models in an automated and inexpensive way. This research investigates the potential of a mini UAV, equipped with a Panasonic Lumix DMC-LX5 compact camera, to provide surface deformations at acceptable levels of accuracy for landslide assessment. The study adopts a self-calibrating bundle adjustment-SfM pipeline using ground control points (GCPs). It evaluates misalignment biases and unresolved systematic errors that are transferred through the SfM process into the derived elevation models. To cross-validate the research outputs, results are compared to benchmark observations obtained by standard surveying techniques. The data is collected with 6 cm ground sample distance (GSD) and is shown to achieve planimetric and vertical accuracy of a few centimetres at independent check points (ICPs). The co-registration error of the generated elevation models is also examined in areas of stable terrain. Through this error assessment, the study estimates that the vertical sensitivity to real terrain change of the tested landslide is equal to 9 cm.


Author(s):  
P. Trusheim ◽  
C. Heipke

Abstract. Localization is one of the first steps in navigation. Especially due to the rapid development in automated driving, a precise and reliable localization becomes essential. In this paper, we report an investigation of the usage of dynamic ground control points (GCP) in visual localization in an automotive environment. Instead of having fixed positions, dynamic GCPs move together with the camera. As a measure of quality, we employ the precision of the bundle adjustment results. In our experiments, we simulate and investigate different realistic traffic scenarios. After investigating the role of tie points, we compare an approach using dynamic GCPs to an approach with static GCPs to answer the question how a comparable precision can be reached for visual localization. We show, that in our scenario, where two dynamic GCPs move together with a camera, similar results are indeed obtained to using a number of static GCPs distributed over the whole trajectory. In another experiment, we take a closer look at sliding window bundle adjustments. Sliding windows make it possible to work with an arbitrarily large number of images and to still obtain near real-time results. We investigate this approach in combination with dynamic GCPs and vary the no. of images per window.


Fractals ◽  
2010 ◽  
Vol 18 (03) ◽  
pp. 271-286 ◽  
Author(s):  
HOUSSAM HNAIDI ◽  
ERIC GUÉRIN ◽  
SAMIR AKKOUCHE

This paper presents two self-similar models that allow the control of curves and surfaces. The first model is based on IFS (Iterated Function Systems) theory and the second on subdivision curve and surface theory. Both of these methods employ the detail concept as in the wavelet transform, and allow the multiresolution control of objects with control points at any resolution level.In the first model, the detail is inserted independently of control points, requiring it to be rotated when applying deformations. In contrast, the second method describes details relative to control points, allowing free control point deformations.Modeling examples of curves and surfaces are presented, showing manipulation facilities of the models.


1981 ◽  
Vol 35 (4) ◽  
pp. 373-386 ◽  
Author(s):  
S. F. El-Hakim

A special bundle adjustment program has been developed with a built-in automatic gross-error detector which uses the data snooping approach. The program computes, in an efficient way, the exact value of the redundancy numbers for each image point. Using actual data, many of the factors affecting the reliability of bundle adjustment and the ability of the technique to detect gross errors are studied. The effects of different block parameters, point type and location, and the use of additional constraints are presented.


1981 ◽  
Vol 37 (1) ◽  
pp. 1-13
Author(s):  
Einari Kilpelä ◽  
Jan Heikkilä ◽  
Keijo Inkilä

Sign in / Sign up

Export Citation Format

Share Document