scholarly journals An Integrated Reverse Engineering Approach for Accuracy Control of Free-Form Objects

2016 ◽  
Vol 63 (4) ◽  
pp. 647-663
Author(s):  
Vimal Kumar Pathak ◽  
Chitresh Nayak ◽  
Amit Kumar Singh ◽  
Himanshu Chaudhary
Keyword(s):  
Reverse Engineering ◽  
Three Dimensional ◽  
Fem Analysis ◽  
Point Clouds ◽  
3D Models ◽  
Digital Model ◽  
Surface Generation ◽  
Free Form ◽  
Accuracy Control ◽  
Prosthetic Socket

Abstract Computer-aided tools help in shortening and eradicating numerous repetitive tasks that reduces the gap between digital model and actual product. Use of these tools assists in realizing free-form objects such as custom fit products as described by a stringent interaction with the human body. Development of such a model presents a challenging situation for reverse engineering (RE) which is not analogous with the requirement for generating simple geometric models. Hence, an alternating way of producing more accurate three-dimensional models is proposed. For creating accurate 3D models, point clouds are processed through filtering, segmentation, mesh smoothing and surface generation. These processes help in converting the initial unorganized point data into a 3D digital model and simultaneously influence the quality of model. This study provides an optimum balance for the best accuracy obtainable with maximum allowable deviation to lessen computer handling and processing time. A realistic non trivial case study of free-form prosthetic socket is considered. The accuracy obtained for the developed model is acceptable for the use in medical applications and FEM analysis.

A VIRTUAL REVERSE ENGINEERING METHODOLOGY FOR ACCURACY CONTROL OF TRANSTIBIAL PROSTHETIC SOCKET

2016 ◽  
Vol 28 (05) ◽  
pp. 1650037 ◽  
Author(s):  
Vimal Kumar Pathak ◽  
Chitresh Nayak ◽  
Amit Kumar Singh ◽  
Himanshu Chaudhary
Keyword(s):  
Reverse Engineering ◽  
Fem Analysis ◽  
Point Clouds ◽  
3D Models ◽  
Digital Model ◽  
Surface Generation ◽  
Free Form ◽  
Accuracy Control ◽  
Difficult Situation ◽  
Prosthetic Socket

Computer-aided tools help in shortening and eradicating numerous repetitive tasks that reduce the gap between digital model and the actual product. Use of these tools assist in realizing free-form objects such as custom fit products as described by an stringent interaction with the human body. Development of such model presents a difficult situation for reverse engineering (RE), which are not analogous with the requirement for generating simple geometric models. Hence, an alternating way of producing more accurate three-dimensional models is proposed. For creating accurate 3D models, point clouds are processed through filtering technique, segmentation, mesh smoothing and surface generation. These processes help in converting the initial unorganized point data into a 3D digital model and simultaneously influence the quality of the model. This study provides an optimum balance for the best accuracy obtainable with maximum allowable deviation to lesser computer handling and processing time. In this paper, a realistic nontrivial case study of the free-form prosthetic socket is considered. The accuracy obtained for the developed model is acceptable for the use in medical applications and FEM analysis.

Rapid Prototyping Design of 3D Models by Reverse Engineering

2012 ◽  
Vol 215-216 ◽  
pp. 648-651
Author(s):  
Dong Sheng Wang ◽  
Xin Feng Wang
Keyword(s):  
Reverse Engineering ◽  
3D Model ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Back Cover ◽  
Engineering Software ◽  
Feature Lines ◽  
Measuring Machine ◽  
Data Point

The digital measurements of the back cover of a telephone receiver were carried out by a three dimensional measuring machine and the data point clouds of the contours were got. Using reverse engineering software, Imageware, the data point clouds were processed, including of data smoothing, data reducing, data point clouds resample, feature lines extracting and curve fitting. Based on the shape features of the research object, the 3D model of the back cover of the telephone receiver were reconstructed with the boundary curves and the scanning data point groups successfully. Precision evaluation was carried out to the 3D model and the error controlled within 0.2mm.

scholarly journals Weighing trees with lasers: advances, challenges and opportunities

2018 ◽  
Vol 8 (2) ◽  
pp. 20170048 ◽  
Author(s):  
M. I. Disney ◽  
M. Boni Vicari ◽  
A. Burt ◽  
K. Calders ◽  
S. L. Lewis ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Large Scale ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Tree Form ◽  
Form And Function ◽  
Challenges And Opportunities ◽  
And Function ◽  
Non Destructive

Terrestrial laser scanning (TLS) is providing exciting new ways to quantify tree and forest structure, particularly above-ground biomass (AGB). We show how TLS can address some of the key uncertainties and limitations of current approaches to estimating AGB based on empirical allometric scaling equations (ASEs) that underpin all large-scale estimates of AGB. TLS provides extremely detailed non-destructive measurements of tree form independent of tree size and shape. We show examples of three-dimensional (3D) TLS measurements from various tropical and temperate forests and describe how the resulting TLS point clouds can be used to produce quantitative 3D models of branch and trunk size, shape and distribution. These models can drastically improve estimates of AGB, provide new, improved large-scale ASEs, and deliver insights into a range of fundamental tree properties related to structure. Large quantities of detailed measurements of individual 3D tree structure also have the potential to open new and exciting avenues of research in areas where difficulties of measurement have until now prevented statistical approaches to detecting and understanding underlying patterns of scaling, form and function. We discuss these opportunities and some of the challenges that remain to be overcome to enable wider adoption of TLS methods.

scholarly journals Integration, Processing and Dissemination of LiDAR Data in a 3D Web-GIS

2019 ◽  
Vol 8 (3) ◽  
pp. 144 ◽  
Author(s):  
Marek Kulawiak ◽  
Marcin Kulawiak ◽  
Zbigniew Lubniewski
Keyword(s):  
Survey Data ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Web Gis ◽  
Data Organization ◽  
3D Model Reconstruction ◽  
Open Standards ◽  
3D Lidar ◽  
The City

The rapid increase in applications of Light Detection and Ranging (LiDAR) scanners, followed by the development of various methods that are dedicated for survey data processing, visualization, and dissemination constituted the need of new open standards for storage and online distribution of collected three-dimensional data. However, over a decade of research in the area has resulted in a number of incompatible solutions that offer their own ways of disseminating results of LiDAR surveys (be it point clouds or reconstructed three-dimensional (3D) models) over the web. The article presents a unified system for remote processing, storage, visualization, and dissemination of 3D LiDAR survey data, including 3D model reconstruction. It is built with the use of open source technologies and employs open standards, such as 3D Tiles, LASer (LAS), and Object (OBJ) for data distribution. The system has been deployed for automatic organization, processing, and dissemination of LiDAR surveys that were performed in the city of Gdansk. The performance of the system has been measured using a selection of LiDAR datasets of various sizes. The system has shown to considerably simplify the process of data organization and integration, while also delivering tools for easy discovery, inspection, and acquisition of desired datasets.

scholarly journals Three-Dimensional Reconstruction of Structural Surface Model of Heritage Bridges Using UAV-Based Photogrammetric Point Clouds

2019 ◽  
Vol 11 (10) ◽  
pp. 1204 ◽  
Author(s):  
Yue Pan ◽  
Yiqing Dong ◽  
Dalei Wang ◽  
Airong Chen ◽  
Zhen Ye
Keyword(s):  
Classification Tree ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Surface Model ◽  
Reconstruction Method ◽  
3D Point Clouds ◽  
Surface Models ◽  
Structural Surface ◽  
Better Than

Three-dimensional (3D) digital technology is essential to the maintenance and monitoring of cultural heritage sites. In the field of bridge engineering, 3D models generated from point clouds of existing bridges is drawing increasing attention. Currently, the widespread use of the unmanned aerial vehicle (UAV) provides a practical solution for generating 3D point clouds as well as models, which can drastically reduce the manual effort and cost involved. In this study, we present a semi-automated framework for generating structural surface models of heritage bridges. To be specific, we propose to tackle this challenge via a novel top-down method for segmenting main bridge components, combined with rule-based classification, to produce labeled 3D models from UAV photogrammetric point clouds. The point clouds of the heritage bridge are generated from the captured UAV images through the structure-from-motion workflow. A segmentation method is developed based on the supervoxel structure and global graph optimization, which can effectively separate bridge components based on geometric features. Then, recognition by the use of a classification tree and bridge geometry is utilized to recognize different structural elements from the obtained segments. Finally, surface modeling is conducted to generate surface models of the recognized elements. Experiments using two bridges in China demonstrate the potential of the presented structural model reconstruction method using UAV photogrammetry and point cloud processing in 3D digital documentation of heritage bridges. By using given markers, the reconstruction error of point clouds can be as small as 0.4%. Moreover, the precision and recall of segmentation results using testing date are better than 0.8, and a recognition accuracy better than 0.8 is achieved.

scholarly journals INTEGRATION OF GEODATA IN DOCUMENTING CASTLE RUINS

2016 ◽  
Vol XLI-B3 ◽  
pp. 345-349
Author(s):  
P. Delis ◽  
M. Wojtkowska ◽  
P. Nerc ◽  
I. Ewiak ◽  
A. Lada
Keyword(s):  
Laser Scanning ◽  
Three Dimensional ◽  
Digital Camera ◽  
Terrestrial Laser Scanning ◽  
Point Clouds ◽  
3D Models ◽  
Digital Imagery ◽  
Historical Structures ◽  
Three Dimensional Models ◽  
Different Sources

Textured three dimensional models are currently the one of the standard methods of representing the results of photogrammetric works. A realistic 3D model combines the geometrical relations between the structure’s elements with realistic textures of each of its elements. Data used to create 3D models of structures can be derived from many different sources. The most commonly used tool for documentation purposes, is a digital camera and nowadays terrestrial laser scanning (TLS). Integration of data acquired from different sources allows modelling and visualization of 3D models historical structures. Additional aspect of data integration is possibility of complementing of missing points for example in point clouds. The paper shows the possibility of integrating data from terrestrial laser scanning with digital imagery and an analysis of the accuracy of the presented methods. The paper describes results obtained from raw data consisting of a point cloud measured using terrestrial laser scanning acquired from a Leica ScanStation2 and digital imagery taken using a Kodak DCS Pro 14N camera. The studied structure is the ruins of the Ilza castle in Poland.

scholarly journals APPLICATIONS OF PANORAMIC IMAGES: FROM 720° PANORAMA TO INTERIOR 3D MODELS OF AUGMENTED REALITY

2015 ◽  
Vol XL-4/W5 ◽  
pp. 189-192 ◽  
Author(s):  
I.-C. Lee ◽  
F. Tsai
Keyword(s):  
Augmented Reality ◽  
Focal Length ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Exterior Orientation ◽  
3D Point Clouds ◽  
Panoramic Images ◽  
Main Station ◽  
Orientation Parameters

A series of panoramic images are usually used to generate a 720° panorama image. Although panoramic images are typically used for establishing tour guiding systems, in this research, we demonstrate the potential of using panoramic images acquired from multiple sites to create not only 720° panorama, but also three-dimensional (3D) point clouds and 3D indoor models. Since 3D modeling is one of the goals of this research, the location of the panoramic sites needed to be carefully planned in order to maintain a robust result for close-range photogrammetry. After the images are acquired, panoramic images are processed into 720° panoramas, and these panoramas which can be used directly as panorama guiding systems or other applications. <br><br> In addition to these straightforward applications, interior orientation parameters can also be estimated while generating 720° panorama. These parameters are focal length, principle point, and lens radial distortion. The panoramic images can then be processed with closerange photogrammetry procedures to extract the exterior orientation parameters and generate 3D point clouds. In this research, VisaulSFM, a structure from motion software is used to estimate the exterior orientation, and CMVS toolkit is used to generate 3D point clouds. Next, the 3D point clouds are used as references to create building interior models. In this research, Trimble Sketchup was used to build the model, and the 3D point cloud was added to the determining of locations of building objects using plane finding procedure. In the texturing process, the panorama images are used as the data source for creating model textures. This 3D indoor model was used as an Augmented Reality model replacing a guide map or a floor plan commonly used in an on-line touring guide system. <br><br> The 3D indoor model generating procedure has been utilized in two research projects: a cultural heritage site at Kinmen, and Taipei Main Station pedestrian zone guidance and navigation system. The results presented in this paper demonstrate the potential of using panoramic images to generate 3D point clouds and 3D models. However, it is currently a manual and labor-intensive process. A research is being carried out to Increase the degree of automation of these procedures.

scholarly journals Modelling and Visualization of Three Dimensional Objects Using Inexpensive Digital Cameras

2018 ◽  
Author(s):  
Ismail Elkhrachy
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Bundle Adjustment ◽  
Control Points ◽  
Digital Cameras ◽  
Three Dimensional Objects ◽  
Spatial Positioning ◽  
And Control

This paper analyses and evaluate the precision and the accuracy the capability of low-cost terrestrial photogrammetry by using many digital cameras to construct a 3D model of an object. To obtain the goal, a building façade has imaged by two inexpensive digital cameras such as Canon and Pentax camera. Bundle adjustment and image processing calculated by using Agisoft PhotScan software. Several factors will be included during this study, different cameras, and control points. Many photogrammetric point clouds will be generated. Their accuracy will be compared with some natural control points which collected by the laser total station of the same building. The cloud to cloud distance will be computed for different comparison 3D models to investigate different variables. The practical field experiment showed a spatial positioning reported by the investigated technique was between 2-4cm in the 3D coordinates of a façade. This accuracy is optimistic since the captured images were processed without any control points.

Dynamic Multi-Sensor Platform for Efficient Three-Dimensional-Digitalization of Cities

2020 ◽  
Vol 20 (4) ◽  
Author(s):  
Angel-Iván García-Moreno
Keyword(s):  
Three Dimensional ◽  
3D Models ◽  
Urban Environments ◽  
Surface Generation ◽  
Laser Sensors ◽  
Post Process ◽  
3D Data ◽  
Sensor Platform ◽  
Technical Report ◽  
Textured Models

Abstract Three-dimensional urban reconstruction requires the combination of data from different sensors, such as cameras, inertial systems, GPS, and laser sensors. In this technical report, a complete system for the generation of textured volumetric global maps (deep vision) is presented. Our acquisition platform is terrestrial and moves through different urban environments digitizing them. The report is focused on describing the three main problems identified in this type of works. (1) The acquisition of three-dimensional data with high precision, (2) the extraction of the texture and its correlation with the 3D data, and (3) the generation of the surfaces that describe the components of the urban environment. It also describes the methods implemented to extrinsically calibrate the acquisition platform, as well as the methods developed to eliminate the radial and tangential image distortion; and the subsequent generation of a panoramic image. Procedures are developed for the sampling of 3D data and its smoothing. Subsequently, the process to generate textured global maps with a negligible uncertainty is developed and the results are presented. Finally, the process of surface generation and the post-process of eliminating certain holes/occlusions in the meshes are reported. In each section, results obtained are shown. Using the methods presented here for geometric and photorealistic reconstruction of urban environments, high-quality 3D models are generated. The results achieved the following objectives: generate global textured models that preserve the geometry of the scanned scenes.

Sign in / Sign up

Export Citation Format

Share Document