Comparison of automated post-processing techniques for measurement of body surface area from 3D photonic scans

Body surface area (BSA) measurement is important in engineering and medicine fields to determine parameters for various applications. Three-dimensional scanning techniques may be used to acquire the BSA directly. Nevertheless, the raw data obtained from 3D scanning usually requires some manual post-processing which is time-consuming and requires technical expertise. Automated post-processing of 3D scans enables expedient BSA calculation with minimal technical expertise. The purpose of this research was to compare the accuracy and reliability of three different automated post-processing techniques including Stitched Puppet (SP), Poisson surface reconstruction (PSR), and screened Poisson surface reconstruction (SPSR) using manual post-processing as the criterion. Twenty-nine participants were scanned twice, and raw data were processed with the manual operation and automated techniques to acquire BSAs separately. The reliability of BSAs acquired from these approaches was represented by the relative technical error of measurements (TEM). Pearson’s regressions were applied to correct BSAs acquired from the automated techniques. The limits of agreement (LOA) were used to quantify the accuracy of BSAs acquired from the automated techniques and corrected by regression models. The reliability (relative TEM) of BSAs obtained from PSR, SPSR and SP were 0.32%, 0.30%, 0.82% respectively. After removing bias with the regression models, the LOA for PSR, SPSR and SP were (-0.0134 m2, 0.0135 m2), ±0.0131 m2, ±0.0573 m2 respectively. It is concluded that PSR and SPSR are good alternative approaches to manual post-processing for applications that need reliable and accurate measurements of BSAs with large populations

An approach for real world data modelling with the 3D terrestrial laser scanner for built environment

Capturing and modelling 3D information of the built environment is a big challenge. A number of techniques and technologies are now in use. These include EDM, GPS, and photogrammetric application, remote sensing and traditional building surveying applications. However, use of these technologies cannot be practical and efficient in regard to time, cost and accuracy. Furthermore, a multi disciplinary knowledge base, created from the studies and research about the regeneration aspects is fundamental: historical, architectural, archeologically, environmental, social, economic, etc. In order to have an adequate diagnosis of regeneration, it is necessary to describe buildings and surroundings by means of documentation and plans. However, at this point in time the foregoing is considerably far removed from the real situation, since more often than not it is extremely difficult to obtain full documentation and cartography, of an acceptable quality, since the material, constructive pathologies and systems are often insufficient or deficient (flat that simply reflects levels, isolated photographs,..). Sometimes the information in reality exists, but this fact is not known, or it is not easily accessible, leading to the unnecessary duplication of efforts and resources. In this paper, we discussed 3D laser scanning technology, which can acquire high density point data in an accurate, fast way. Besides, the scanner can digitize all the 3D information concerned with a real world object such as buildings, trees and terrain down to millimetre detail Therefore, it can provide benefits for refurbishment process in regeneration in the Built Environment and it can be the potential solution to overcome the challenges above. The paper introduce an approach for scanning buildings, processing the point cloud raw data, and a modelling approach for CAD extraction and building objects classification by a pattern matching approach in IFC (Industry Foundation Classes) format. The approach presented in this paper from an undertaken research can lead to parametric design and Building Information Modelling (BIM) for existing structures. Two case studies are introduced to demonstrate the use of laser scanner technology in the Built Environment. These case studies are the Jactin House Building in East Manchester and the Peel building in the campus of University Salford. Through these case studies, while use of laser scanners are explained, the integration of it with various technologies and systems are also explored for professionals in Built Environmen

Measuring volume of stockpile using imaging station

It is crucial to know cutting and filling volumes in many surveys, mining, quarry and engineering field of works like dredging and embankment project. Generally, volume calculation is completed using conventional surveying methods. The trapezoidal method and classical cross sectioning have been presented in the literature. In other way around, by using conventional surveying methods, the volume calculation required a lot of time, laborers and risky as the big machineries running around the work areas. Digital close range photogrammetry has been insufficient for the volume calculation of the material need to calculation of volume in risk areas or in short time. In this case, long range surveying and scanning method is an alternative method to volume calculation. By the development of scanning and imaging technologies, Topcon Imaging Station (IS) used for three dimensional modeling (3D) surveying of objects in many field such as topographic survey, mining, construction and as-built survey, etc disciplines has become a productive, faster and accurate method. This study concern is getting the stockpile volume by using Topcon IS known as advanced technology instrument which promotes both scanning and long-range surveying. The instrument, a highly-developed technology specialized with Image Master Software; distinctive software that provides capabilities to reconstructed 3D modeling after the volume data was processed. Three dimensional (3D) surfaces are created through Triangulated Irregular Network (TIN) method that supports time saving and more accurate volume calculation. The volume calculated by Image Master (IM) then compared with the volume calculated by 12D software which the data obtained by using total station and prism. The results have been analyzed with respect to different volumes, density factor, three dimensional (3D) models of stockpile and time taken for data acquisition and data processin

3D FEM model development from 3D optical measurement technique applied to corroded steel bars

Understanding the mechanical effects of the corrosion pits on the steel surface requires an accurate definition of their geometry and distribution along the rebar. 3D optical measurement technique is used to obtain the outer geometry of artificially corroded bars tested under cyclic or monotonic loads. 3D FEM model development from the 3D scanning results were carried out in order to investigate the failure process and local effects on the pits, which are responsible of the variation of the mechanical properties in corroded steel reinforcement. In addition, a validation of a simplified model, which allows the mechanical steel properties determination given an estimated corrosion level, is presented. 3D models were convenient to observe and measure the local effects on the pits.Peer ReviewedPostprint (author's final draft

Point Cloud Framework for Rendering 3D Models Using Google Tango

This project seeks to demonstrate the feasibility of point cloud meshing for capturing and modeling three dimensional objects on consumer smart phones and tablets. Traditional methods of capturing objects require hundreds of images, are very slow and consume a large amount of cellular data for the average consumer. Software developers need a starting point for capturing and meshing point clouds to create 3D models as hardware manufacturers provide the tools to capture point cloud data. The project uses Googles Tango computer vision library for Android to capture point clouds on devices with depth-sensing hardware. The point clouds are combined and meshed as models for use in 3D rendering projects. We expect our results to be embraced by the Android market because capturing point clouds is fast and does not carry a large data footprint

An experimental study to test a 3D laser Scanner for body measurement and 3D virtual garment design in Fashion education

Artists, scientists, anthropometrists and tailors have accurately measured the human body with traditional tools, such as tape measures, callipers and accumulated visceral experience for centuries. Due to the progressive acceleration in the quality of 3D graphics technology and computer processing power, many product industries that traditionally use 3D software as a 3D design and prototyping tool, are also successfully measuring, customizing and re-engineering the products they design and manufacture through the integrated use of 3D Laser scanning technology. In the changing world of Fashion, 3D graphics technology has at last emerged from the shadows of academic research projects and hit the high streets. 3D body measurement surveys, using mobile 3D laser scanners, have mapped the true shape and body sizes of the UK and USA populations. Virtual fit and 3D visualisation technology has expanded out from the Internet, into the physical world, and is now available for shoppers to visualise made to measure garments. The acceptance of three-dimensional body-scanning and 3D digital design tools into our everyday experiences can be seen as a significant move toward encouraging and developing new, innovative learning and teaching methods in Art & Design education. This paper describes an experimental study into the application of 3D laser scanner technology for use in learning and teaching of undergraduate and postgraduate fashion and textiles design; clothing manufacture, fashion marketing, merchandising and promotion. The study focuses on testing the 3D scanning equipment with a student sample group. The use of the sample group attempts to simulate a range of body shapes, categorised by the traditional standard size chart specification method, currently used to design new fashion collections for high street clothing retail and UK fashion education. The methods applied for evaluation and testing of the 3D laser scanner for body measurement are described, and the results of the initial user experiences are discussed. The study seeks to establish the overall efficiency of 3D scanning technology and investigates the potential value for integration of the 3D Laser scanner with 3D clothing design and construction software. Conclusions provide recommendations on the potential effectiveness of connecting the results of the 3D body measurement study to the fashion curriculu

An intelligent real time 3D vision system for robotic welding tasks

MARWIN is a top-level robot control system that has been designed for automatic robot welding tasks. It extracts welding parameters and calculates robot trajectories directly from CAD models which are then verified by real-time 3D scanning and registration. MARWIN's 3D computer vision provides a user-centred robot environment in which a task is specified by the user by simply confirming and/or adjusting suggested parameters and welding sequences. The focus of this paper is on describing a mathematical formulation for fast 3D reconstruction using structured light together with the mechanical design and testing of the 3D vision system and show how such technologies can be exploited in robot welding tasks

Determination of stress concentration factors in offshore wind welded structures through a hybrid experimental and numerical approach

Offshore wind turbine (OWT) monopile support structures generally consist of steel cans connected together through circumferential welding joints. One critical factor to evaluate the localised increase in stresses is the stress concentration factor (SCF) which depends on the welding quality. The complex welding profiles in OWT monopiles makes the accurate calculation of SCF quite challenging. In this work, an innovative approach for the calculation of SCFs in offshore welded structures is proposed based on combined 3D (three-dimensional) laser scanning technology (LST) and 3D finite element analysis (FEA). The precise geometry of the welded specimens is captured using 3D LST, and then imported into a finite element software to perform 3D FEA modelling to accurately calculate SCFs. A 2D (two-dimensional) FEA model of a typical offshore welded structure with ideal geometry is also developed in this work. In addition to numerically calculate SCFs, the 2D FEA model is further combined with non-linear RSM (response surface method) to derive analytical equations, expressing SCFs of offshore welded structures in terms of key welding parameters. Both LST-FEA3D and RSM-FEA2D models are applied to calculate SCFs in large-scale S-N fatigue welded specimens. The results indicate that the LST-FEA3D approach is capable of capturing the variation of SCFs along the width of the welded specimens and identifying the critical points where fatigue crack is most likely to initiate; and the RSM-FEA2D is valuable and efficient in deriving analytical parametric equations for SCFs

Development of a viable concrete printing process

A novel Concrete Printing process has been developed, inspired and informed by advances in 3D printing, which has the potential to produce highly customised building components. Whilst still in their infancy, these technologies could create a new era of architecture that is better adapted to the environment and integrated with engineering function. This paper describes the development of a viable concrete printing process with a practical example in designing and manufacturing a concrete component (called Wonder Bench) that includes service voids and reinforcement. The challenges met and those still to be overcome particularly in the evaluation of the manufacturing tolerances of prints are also discussed