Automatic alignment of piping system components and generation of CAD models of industrial site plants

The ability to (semi-)automatically obtain CAD models from physical installations has two important benefits: (i) it can be used to identify, as soon as possible during a con struction process, any deviations from the original designs; and (ii) it can be used to document complex installations for which CAD representations are outdated or inexis tent. Both scenarios have important practical and economic value. An ongoing project in our research group aims to reconstruct CAD representations from point clouds of in dustrial sites. However, pose estimation of pipes and piping system components is not perfect, resulting in misalignments in the reconstructed scene, which is unacceptable for a CAD model. For this undergraduate thesis, I propose to use optimization techniques to fix these misalignments. I also propose to convert the detected pipes and piping system components into actual CAD model representations for a popular commercial CAD soft ware, namely AutoCAD Plant 3D

Reconstruction of industrial piping installations from laser point clouds using profiling techniques

Includes abstract.Includes bibliographical references (leaves 143-152).As-built models of industrial piping installations are essential for planning applications in industry. Laser scanning has emerged as the preferred data acquisition method of as built information for creating these three dimensional (3D) models. The product of the scanning process is a cloud of points representing scanned surfaces. From this point cloud, 3D models of the surfaces are reconstructed. Most surfaces are of piping elements e.g. straight pipes, t-junctions, elbows, spheres. The automatic detection of these piping elements in point clouds has the greatest impact on the reconstructed model. Various algorithms have been proposed for detecting piping elements in point clouds. However, most algorithms detect cylinders (straight pipes) and planes which make up a small percentage of piping elements found in industrial installations. In addition, these algorithms do not allow for deformation detection in pipes. Therefore, the work in this research is aimed at the detection of piping elements (straight pipes, elbows, t-junctions and flange) in point clouds including deformation detection

Semi automatic construction progress measurement using a combination of CAD modelling, photogrammetry and construction knowledge

Project managers are lacking up-to-date information about the current stage of the work on the site and they are unable to take corrective measures for the planning variations promptly. It is proposed that the method created within this thesis will reduce this problem greatly by supplying project managers with the data they need to understand schedule and cost variances as early as they occur. This gives them the power to step in and act in good time against the problems by identifying the reasons of the variations much earlier. This thesis is one of the attempts within academia about integrating computer based solutions to monitor and visualise construction progress. Photogrammetric measurements offer reliable results at the cost of more human intervention. This approach offers the possibility of using a hand held camera as a measurement tool. This method also offers complete independence from reliance on the planning and design stage information. Hence, it can be used to re-evaluate, or monitor changes during the project life-cycle. Visible physical body of a superstructure level reinforced concrete frame structure consists of walls, floors, beams, and columns. The building regulations and local construction traditions impose the types and the shapes of these structural elements. The manufacturing industry produces building materials such as bricks and floor blocks in standard sizes. Therefore, it can be seen that knowledge about the design criteria of structural elements or the standard sizes of materials available on the market for construction can be used to create 3D models of building components. A Visual Basic for Applications (VBA) code was created to support these theories and presented in this thesis. The code then was tested and proven to be useful. After comparing the manual measurement results against the outcomes of the case study done for testing the proposed model, it has been revealed that the proposed model can produce 3D model of construction with accurate sizes within similar mistake margins which can be achieved manually

Doctor of Philosophy

dissertationThree-dimensional (3D) models of industrial plant primitives are used extensively in modern asset design, management, and visualization systems. Such systems allow users to efficiently perform tasks in Computer Aided Design (CAD), life-cycle management, construction progress monitoring, virtual reality training, marketing walk-throughs, or other visualization. Thus, capturing industrial plant models has correspondingly become a rapidly growing industry. The purpose of this research was to demonstrate an efficient way to ascertain physical model parameters of reflectance properties of industrial plant primitives for use in CAD and 3D modeling visualization systems. The first part of this research outlines the sources of error corresponding to 3D models created from Light Detection and Ranging (LiDAR) point clouds. Fourier analysis exposes the error due to a LiDAR system's finite sampling rate. Taylor expansion illustrates the errors associated with linearization due to flat polygonal surfaces. Finally, a statistical analysis of the error associated with LiDar scanner hardware is presented. The second part of this research demonstrates a method for determining Phong specular and Oren-Nayar diffuse reflectance parameters for modeling and rendering pipes, the most ubiquitous form of industrial plant primitives. For specular reflectance, the Phong model is used. Estimates of specular and diffuse parameters of two ideal cylinders and one measured cylinder using brightness data acquired from a LiDAR scanner are presented. The estimated reflectance model of the measured cylinder has a mean relative error of 2.88% and a standard deviation of relative error of 4.0%. The final part of this research describes a method for determining specular, diffuse and color material properties and applies the method to seven pipes from an industrial plant. The colorless specular and diffuse properties were estimated by numerically inverting LiDAR brightness data. The color ambient and diffuse properties are estimated using k-means clustering. The colorless properties yielded estimated brightness values that are within an RMS of 3.4% with a maximum of 7.0% and a minimum of 1.6%. The estimated color properties effected an RMS residual of 13.2% with a maximum of 20.3% and a minimum of 9.1%

OPEN SOURCE HBIM FOR CULTURAL HERITAGE: A PROJECT PROPOSAL

Actual technologies are changing Cultural Heritage research, analysis, conservation and development ways, allowing new innovative approaches. The possibility of integrating Cultural Heritage data, like archaeological information, inside a three-dimensional environment system (like a Building Information Modelling) involve huge benefits for its management, monitoring and valorisation. Nowadays there are many commercial BIM solutions. However, these tools are thought and developed mostly for architecture design or technical installations. An example of better solution could be a dynamic and open platform that might consider Cultural Heritage needs as priority. Suitable solution for better and complete data usability and accessibility could be guaranteed by open source protocols. This choice would allow adapting software to Cultural Heritage needs and not the opposite, thus avoiding methodological stretches. This work will focus exactly on analysis and experimentations about specific characteristics of these kind of open source software (DBMS, CAD, Servers) applied to a Cultural Heritage example, in order to verifying their flexibility, reliability and then creating a dynamic HBIM open source prototype. Indeed, it might be a starting point for a future creation of a complete HBIM open source solution that we could adapt to others Cultural Heritage researches and analysis

Generating bridge geometric digital twins from point clouds

The automation of digital twinning for existing bridges from point clouds remains unsolved. Extensive manual effort is required to extract object point clusters from point clouds followed by fitting them with accurate 3D shapes. Previous research yielded methods that can automatically generate surface primitives combined with rule-based classification to create labelled cuboids and cylinders. While these methods work well in synthetic datasets or simplified cases, they encounter huge challenges when dealing with realworld point clouds. In addition, bridge geometries, defined with curved alignments and varying elevations, are much more complicated than idealized cases. None of the existing methods can handle these difficulties reliably. The proposed framework employs bridge engineering knowledge that mimics the intelligence of human modellers to detect and model reinforced concrete bridge objects in imperfect point clouds. It directly produces labelled 3D objects in Industry Foundation Classes format without generating low-level shape primitives. Experiments on ten bridge point clouds indicate the framework achieves an overall detection F1-score of 98.4%, an average modelling accuracy of 7.05 cm, and an average modelling time of merely 37.8 seconds. This is the first framework of its kind to achieve high and reliable performance of geometric digital twin generation of existing bridges

Automation, Digitalization, and Changes in Occupational Structures in the Automobile Industry in Germany, the United States, and Japan: A Brief History from the Early 1990s Until 2018

In the current public discussion, it is considered certain that we are living in a time of rapidly advancing automation, which is driven in particular by the use of robots. Accordingly, many academic publications use robot density as the central indicator of automation. The present study challenges this perspective. It examines two central questions: First, what approaches to automation and digitalization have been pursued in the automotive industry in Germany, Japan and the USA? Second, how have employment and its occupational composition in the automotive industry developed in the three countries? The first part of the study focuses on the development of automation and digitalization approaches in the automotive industry from the early 1990s until today. It combines a qualitative analysis of press articles and a quantitative evaluation of the development of the stock of industrial robots from 1993 to 2018 based on the statistics of the International Federation of Robotics. The second part of the study focuses on the change in employment structures using occupational statistics from the Bureau of Labor Statistics (USA), the Federal Employment Agency (Germany) and the Statistics Bureau of Japan. The study questions the perception of an automation-related threat to employment and especially to production employment. At the same time, it discusses developments in Germany, Japan and the USA in comparison and highlights differences in automation and digitalization approaches as well as different paths of change in employment structures

Building Information Modeling (BIM) for existing buildings - literature review and future needs

Abstract not availableRebekka Volk, Julian Stengel, Frank Schultman