Precise calibration of a rotation photogrammetric system

Rotation photogrammetric systems are widely used for 3D information acquisition,where high-precision calibration is one of the critical steps.This study first shows how to derive the rotation model and deviation model in the object space coordinate system according to the basic structure of the system and the geometric relationship of the related coordinate systems.Then,overall adjustment of multi-images from a surveying station is employed to calibrate the rotation matrix and the deviation matrix of the system.The exterior orientation parameters of images captured by other surveying stations can be automatically calculated for 3D reconstruction.Finally,real measured data from Wumen wall of the Forbidden City is employed to verify the performance of the proposed calibration method.Experimental results show that this method is accurate and reliable and that a millimetre level precision can be obtained in practice.

A NEW APPROACH TO THE DESIGN OF A SYSTEM FOR FEATURE EXTRACTION BASED ON HUMAN-COMPUTER COLLABORATIVE TACTIC

We are involved in an embarrassing situation that the limited capability of automated feature extraction in digital photogrammetric systems cannot satisfy the increasing needs for rapid acquisition of semantic information for applications. Facing this challenge, a new tactic, Human-Computer Collaborative (HCC) tactic, and a corresponding new method, Operator-Object Directed (OOD) method, are proposed for the design of a system for feature extraction from large scale aerial images. We hold that in almost all technical complex systems, full automation will be neither technically feasible nor socially acceptable. The system should be designed to optimize through the cooperative operation with two agents in the system: the hurtan and the computer.

Digital close-range photogrammetric application to small-scale physical simulation experiment

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

Photogrammetric Analysis of Multiple Implant Abutment Impressions under Different Conditions

Purpose: The aim of this investigation was to evaluate and compare the dimensional accuracy of hydrophilic polysiloxane, vinyl polysiloxane (VPS), and polyether (PE) impression materials under dry, moist and wet conditions. Methods: An acrylic master model including 6 implants was formed, and 108 impressions were made up of this acrylic model at total. In this study, the materials of hydrophilic polysiloxane impression material, 1 hydrophilic vinyl polysiloxane impression material and 1 polyether impression material were tested. Twelve impression of each material were created under dry, moist and wet respectively. Two reference distances were evaluated on each study model by using a graphics-editing program whereas for comparison of mean dimensional changes one-way analysis of variance and Student t-test were used. Results: One-way analysis of variance revealed significant differences between impression materials and conditions (P P Conclusions: All impression materials showed a statistically significant difference under dry, moist and wet conditions.

THE SCHEME FOR THE DATABASE BUILDING AND UPDATING OF 1∶10 000 DIGITAL ELEVATION MODELS

The National Bureau of Surveying and Mapping of China has planned to speed up the development of spatial data infrastructure (SDI) in the coming few years.This SDI consists of four types of digital products,i.e.,digital orthophotos,digital elevation models, digital line graphs and digital raster graphs.For the DEM,a scheme for the database building and updating of 1∶10 000 digital elevation models has been proposed and some experimental tests have also been accomplished.This paper describes the theoretical (and/or technical) background and reports some of the experimental results to support the scheme.Various aspects of the scheme such as accuracy,data sources,data sampling,spatial resolution,terrain modeling,data organization,etc are discussed.

Numerical analysis and experimental studies of membrane wrinkles

Wrinkling patterns and the rules of wrinkling formation and expansion were analyzed in this paper. Direct disturbing method,a numerical method for membrane wrinkling analysis,was established based on finite element programme. The experimental results using photogrammetric procedure were compared with numerical analysis results. It is shown that the reasonable wrinkling deformation can be obtained by rational mesh density and timely removes the initial flaw during analysis. Wrinkles firstly appear on the left and right sides then extend to the membrane center,and the wrinkling amplitude increases with shear displacement. Results from both of the experiments and numerical analysis have a good agreement,which verifies the rationality of the numerical analysis method.

The Effectiveness of Different Methodologies in Gathering Information for Developing BIM Models to Support the Operation and Maintenance of Existing Buildings

Systematic, preventive and corrective maintenance is essential for existing buildings in order to retain their original functionality and appearance and satisfy the needs of the users. Essential input for maintenance is information about buildings. This paper discusses the assessment of the advantages and limitations of using photogrammetry and a low-cost 3D scanner to collect information from existing buildings and create, through integrative software, BIM models as information systems to support the operation and maintenance functions. Also, these methodologies were compared with one another as well as with a manual information survey conducted at a university campus. The main conclusion is that a combination of methods must be used to obtain geometrical information on existing buildings for their operation and maintenance functions, depending on which ones are the most suitable for the case at hand.

Photogrammetry and deep learning for energy production prediction and building-integrated photovoltaics decarbonization

Building-Integrated photovoltaics(BIPV)have emerged as a promising sustainable energy solution,relying on accurate energy production predictions and effective decarbonization strategies for efficient deployment.This paper presents a novel approach that combines photogrammetry and deep learning techniques to address the problem of BIPV decarbonization.The method is called BIM-AITIZATION referring to the integration of BIM data,AI techniques,and automation principles.It integrates photogrammetric data into practical BIM parameters.In addition,it enhances the precision and reliability of PV energy prediction by using artificial intelligence strategies.The primary aim of this approach is to offer advanced,data-driven energy forecasts and BIPV decarbonization while fully automating the underlying process.To achieve this,the first step is to capture point cloud data of the building through photogrammetric acquisition.This data undergoes preprocessing to identify and remove unwanted points,followed by plan segmentation to extract the plan facade.After that,a meteorological dataset is assembled,incorporating various attributes that influence energy production,including solar irradiance parameters as well as BIM parameters.Finally,machine and deep learning techniques are used for accurate photovoltaic energy predictions and the automation of the entire process.Extensive experiments are conducted,including multiple tests aimed at assessing the performance of diverse machine learning models.The objective is to identify the most suitable model for our specific application.Furthermore,a comparative analysis is undertaken,comparing the performance of the proposed model against that of various established BIPV software tools.The outcomes reveal that the proposed approach surpasses existing software solutions in both accuracy and precision.To extend its applicability,the approach is evaluated using a building case study,demonstrating its ability to generalize effectively to new building data.

Everything moves:The rapid changes in photogrammetry and remote sensing

Changes in technology are coming at an ever increasing pace.This holds for photogrammetry and remote sensing as well.“Everything moves”-this is why I chose this topic to shed some light on some of the recent developments.Naturally,this undertaking can never be complete in the sense of covering all developments in Photogrammetry and Remote Sensing.Besides,the impact of Deep Learning in photogrammetry is not mentioned in this paper.This is a very personal account.People may not agree with some of my findings,but this is in the nature of science.In any case,this contribution is meant as a tribute to Gottfried’s successful lifelong work.It is not a scientific paper in the traditional sense but rather a collection of thoughts that emerged over the 50 years of my professional career.It is also meant for an audience who has not necessarily a deep photogrammetric expert know-how.

Prediction accuracy of reservoir break flood simulation model using finite volume method and UAV

Methods for producing high-resolution digital topographic maps using an unmanned aerial vehicle(UAV),and 3D fluid dynamics simulation to estimate the flooded areas caused by a collapsed reservoir,were proposed in this paper.The UAV flight path for photographing damaged areas was divided into two sections considering the drone flight time and overlapping range of the images in the x-and y-directions.The metadata taken by the drone were transferred into world coordinates by tracking the key features of the photographs of nearby areas using a 3D rotation matrix.The point cloud data with a 3D space were extracted from the registered images,and a digital surface map(DSM)was produced using a point cloud classification geometric mapping technique.To amend the serious elevation errors caused by natural or artificial obstacles,a kriging interpolation method was used to reproduce the DSM.A transient computational simulation that considers both the complex geometric topology and hydrodynamic energy of flowing water was conducted using FLOW-3D software to deal with an renormalization group(RNG)turbulence model.The flooded areas calculated through visual reading using images taken by the UAV were compared with the 3D simulation results for verification.The flooded areas estimated through the simulation were approximately 18.3%larger than those found by visual reading.Turbulent flows were mainly observed in obstacles or curved areas of the stream,and the differences in the water depth could be further increased.However,the villagers confirmed that the flooded areas were much greater than what was seen through the visual reading.Therefore,the combination of UAV surveying and the 3D simulation method based on the RNG turbulence model is recommended to accurately estimate flooded areas,and it will support an administrative policy aimed at minimizing the economic costs of damage caused by future reservoir collapses.

Investigating the influential post-disaster factors in determining the optimal location of shelters:A case study,Sarpol-e Zahab,Kermanshah province,Iran

A proper location is one of the most influential factors in shelter performance.Although considerable research focuses on finding a suitable site for temporary shelters,only a few address the effect of post-disaster circumstances on discovering the optimal location.This study primarily aims to investigate the influential factors in determining a suitable place for temporary shelters after a crisis.Therefore,an algorithm is proposed.This algorithm is achieved by analyzing and computing the post-crisis urban route and facility accessibility based on photogrammetric photographs taken by an unmanned aerial vehicle/satellite.

Architectural survey of historical buildings:The orders of classical architecture in the Baptistery of Florence

The survey of historic buildings is very important for architectural conservation.An integral survey allows perpetuating the building historical memory,deciphering it for future generations,and recovering it in case of accidental loss.The Baptistery of Florence survey was done with four measuring methods:the"direct"one,which employs traditional measuring tools;the"indirect"one,which expedites the dimension-gathering process with more preci-sion;and the"photogrammetric"one,which uses snapshots to facilitate the representation process with computers.An innova tive measuring concept,known here as the"recovery sur-vey",synthetizes graphical reality so that irregularities--due to the project materialization and deterioration over time-disappear;therefore,retrieving the building original design.Col-umns with their bases,shafts and capitals,as well as entablatures with their architraves,friezes and cornices were under study.The three Greek orders(Doric,lonic and Corinthian)together with the two roman orders(Tuscan and Composite)unveiled the classical architecture significance.These constituents,which reoccur inside and outside the baptistery,were measured as part of these holistic survey and recovery process,to achieve the objective of this research study:the recording of this world historical building through an integral survey and rilievo to decode its significance and symbolism.

An improved approach for the production of satellite-based geospatialreference imagery

An innovative and practical satellite image product is described that is ideal for applications in Northern Canada because of its wide area coverage and mappingquality features.This product is generated from a new procedure developed at the Canada Centre for Remote Sensing(CCRS)for processing Landsat 7 imagery,and by extension,imagery from other Earth Observation satellites.By working with multiple satellite passes,each containing the equivalent of multiple scenes,the new procedure could dramatically reduce the turn-around time for generating georeferenced image products,and also increase their geometric and radiometric accuracy compared to those produced by the current methods.The objective of the process has been to generate satellite image mosaics covering large areas(e.g.>500000 km^(2))with uniformly distributed errors at sub-pixel resolution.The paper discusses the theoretical basis of a photogrammetric adjustment for satellite imagery and the results obtained from several tests.The process is generic,involving a sensor model,a satellite orbit model and ground control information;thus it may be easily adapted to any satellite that allows for repeat coverage with overlapping paths.By performing an adjustment to correct the satellite position and attitude data prior to the production of orthoimage products,it is possible to create a mosaic with a single resampling process which minimises both the radiometric and geometric resampling artifacts.The results from three separate tests are presented,along with a discussion of the procedures that were followed in each case.All three tests have successfully demonstrated that sub-pixel sample size errors may be consistently obtained over large areas.A by-product process developed to support the measurement of ground control point coordinates for the satellite adjustment was the automatic matching of geographic features such as lakes and islands in vector data format.This has been a significant development in that it has eliminated manual intervention in the measurement of these features in the imagery,allowing the ground control for entire passes containing several scenes to be obtained in minutes instead of hours.

On the Possibilities of using Some Modern Three-dimensional Modeling Means in Forensic Examination

Background:The paper examines the state and prospects of using 3D modeling in solving identification,classification,diagnostic and situational tasks of forensic examination.Aims and Objectives:The aim of this study is to analyze the world expert practice of using scientific and technical means of three-dimensional modeling in solving problems of forensic examination,using the example of our country,the leading countries of Europe,as well as the United States.Materials and Methods:The empirical basis of the study is the results of the systematization of scientific and technical means for 3D modeling in solving identification,classification,diagnostic and situational problems of forensic examinations used in the expert practice of Ukraine,the United Kingdom,France,Germany,and the USA.Results:The systematization of modem scientific and technical means for 3D modeling,used in solving identification,classification,diagnostic and situational tasks of forensic examination,has been carried out.We analyzed and identified 3D modeling software that most fully meets the requirements of effective forensic expert activities.The features of the use of effective 3D modeling mean for solving identification,classification,diagnostic and situational tasks of forensic examination,namely the software systems"ToolScan"and"TrasoScan",and the SketchUp program have been disclosed.Conclusion:The introduction of the SketchUp 8 software into forensic expert activities will increase the effectiveness of the modeling method in forensic examinations,which,in turn,will have an impact on the effectiveness of expert conclusions,increase their evidentiary value and,as a result,contribute to the entire process of a criminal investigation.