Plane segmentation from point clouds

Recently, attempts have been made to automate data acquisition, which is also related to efforts to automate data processing. The paper deals with the automation of terrestrial laser scanning data processing. The approaches for point cloud segmentation are briefly described. An algorithm based on random sample consensus is proposed for automated plane identification and plane segmentation from point clouds. The proposed approach was tested by processing point clouds; the results of the testing are also described. Based on the proposed algorithm, a standalone application for automated plane segmentation from laser scanner data using Matlab® software was developed

Semi-Automated Segmentation of Geometric Shapes from Point Clouds

Building information models (BIM) in the civil industry are very popular nowadays. The basic information of these models is the 3D geometric model of a building structure. The most applied methodology to model the existing buildings is by generating 3D geometric information from point clouds provided by laser scanners. The fundamental principle of this methodology is the recognition of structures shaped in basic geometric primitives, e.g., planes, spheres, and cylinders. The basic premise of the efficiency of this methodology is the automation of detection, since manual segmentation of a point cloud can be challenging, time-consuming, and, therefore, inefficient. This paper presents a novel algorithm for the automated segmentation of geometric shapes in point clouds without needing pre-segmentation. With the designed algorithm, structures formed in three types of basic geometrical primitive can be identified and segmented: planar (e.g., walls, floors, ceilings), spherical (e.g., laser scanner reference targets), and cylindrical (e.g., columns, pillars, piping). The RANSAC paradigm partially inspires the proposed algorithm; however, various modifications must be made. The algorithm was tested on several point clouds and was compared with the standard RANSAC algorithm; this part is described in the last section of the paper. One of the tests was performed on a double cylinder-shaped test object, the parameters (radius and height) of this object were available with high accuracy (0.1 mm), and the differences between the known and estimated parameters were below 0.5 mm in each case, indicating the correctness of the proposed algorithm. Also, a comparison with the standard RANSAC algorithm was performed, where the algorithm proposed showed better results than the standard RANSAC algorithm. The segmentation quality was, on average, increased from 50% to 100%

Automation of Cylinder Segmentation from Point Cloud Data

The results of terrestrial laser scanning are point clouds, which are becoming an increasingly common initial digital representation of real-world objects. Since point clouds in the most cases represent a huge amount of data, automation of the processing steps is advisable. The paper brings a short review of the most reliable methods of cylinder extraction. An innovative algorithm is proposed for an automated detection of cylinders and also for estimating their parameters from 3D point cloud data. The method was tested on the complex point clouds of pipelines. The proposed algorithm was implemented to a standalone application based on MATLAB® software

Automated Sphere Segmentation from Point Clouds

Nowadays huge datasets can be collected in a relatively short time. After capturing these data sets the next step is their processing. Automation of the processing steps can contribute to efficiency increase, to reduction of the time needed for processing, and to reduction of interactions of the user. The paper brings a short review of the most reliable methods for sphere segmentation. An innovative algorithm for automated detection of spheres and for estimating their parameters from 3D point clouds is introduced. The algorithm proposed was tested on complex point clouds. In the last part of the paper, the implementation of the algorithm proposed to a standalone application is described

Wall Structure Geometry Verification Using TLS Data and BIM Model

Building information modeling (BIM) represents significant progress in the field of digitalization and informatization of the construction process. The virtual model (BIM model) is the source of graphic data among other information, which are applicable for geometry verification of the building’s structures. For this purpose, data and information about the building should be collected. Comparison of the BIM model (design) with as-built 3D models enables the evaluation of the quality of the as-built structures. The most effective methods for spatial data collection are terrestrial laser scanning (TLS) and close-range photogrammetry. Using both methods, measurement can result in a point cloud. The paper describes an approach for verifying the geometry of wall structures. The graphic data of designed structures are represented by the existing BIM model. The approach presented uses the Industry Foundation Classes (IFC) file format from which the designed geometry is derived. The as-built models of the structures are created from point clouds. Point cloud segmentation uses a combination of regression, filtering based on local normal vectors, and curve segmentation. Consequently, the designed and the as-built models (segmented from the point cloud) are compared

Verification of Building Structures Using Point Clouds and Building Information Models

The effort towards automation of the building industry processes has increased significantly over the last years worldwide. One of the key tools in this process is the modeling of buildings using Building Information Modeling (BIM). When following fundamental principles, a BIM model serves as an up-to-date pool of information. Combining the results of effective spatial data collection techniques with the information from a BIM model, it is possible to increase the effectiveness of as-built documentation of the structures or in-site clash detection between the built and planned parts. In this paper, we describe an approach for the verification of building structures by comparing the as-built model created from point clouds with the as-planned model of the building. The point clouds can be collected by laser scanning or photogrammetry, while the geometry of the planned (designed) structures is derived from the BIM model in the Industry Foundation Classes (IFC) format. The advantage of the approach is that the as-built model is created by regression models from point clouds preprocessed by detailed segmentation. The deviations from the design and the relative geometry (e.g., flatness) of the elements are expressed by signed color maps. The presented workflow enables semi-automated verification of building structures

Assessing the Duration of the Lead Appointed Party Coordination Tasks and Evaluating the Appropriate Team Composition on BIM Projects

This paper addresses critical success factors for the delivery of BIM projects. The lack of experience with BIM projects on both the demand and supply side often leads to insufficient project teams, unsatisfied clients, schedule, and cost overruns. In order to better structure and control the information delivery in BIM projects requirements, planning and delivery must be standardized. The latter was achieved by EIR (Exchange Information Requirements), new BIM roles, BEP (BIM Execution Plan), and specified digital handover, which must be supported by a common data environment (CDE). This paper provides an analysis of the characteristics of BIM project delivery and duration in Architectural and Engineering companies in Slovakia. The analysis is based on the web survey of BIM managers and coordinators, which reveals that a significant amount of BIM project efforts must be executed by BIM specialists. The results also graphically depict the scope of critical BIM activities across project phases. The presented study is relevant for various project stakeholders and allows for a deeper understanding of the resources needed for the successful delivery of BIM projects in terms of adequate project team capacity, capability, organization, and planning

Verification of Building Structures Using Point Clouds and Building Information Models

The effort towards automation of the building industry processes has increased significantly over the last years worldwide. One of the key tools in this process is the modeling of buildings using Building Information Modeling (BIM). When following fundamental principles, a BIM model serves as an up-to-date pool of information. Combining the results of effective spatial data collection techniques with the information from a BIM model, it is possible to increase the effectiveness of as-built documentation of the structures or in-site clash detection between the built and planned parts. In this paper, we describe an approach for the verification of building structures by comparing the as-built model created from point clouds with the as-planned model of the building. The point clouds can be collected by laser scanning or photogrammetry, while the geometry of the planned (designed) structures is derived from the BIM model in the Industry Foundation Classes (IFC) format. The advantage of the approach is that the as-built model is created by regression models from point clouds preprocessed by detailed segmentation. The deviations from the design and the relative geometry (e.g., flatness) of the elements are expressed by signed color maps. The presented workflow enables semi-automated verification of building structures

Assessing the Duration of the Lead Appointed Party Coordination Tasks and Evaluating the Appropriate Team Composition on BIM Projects

This paper addresses critical success factors for the delivery of BIM projects. The lack of experience with BIM projects on both the demand and supply side often leads to insufficient project teams, unsatisfied clients, schedule, and cost overruns. In order to better structure and control the information delivery in BIM projects requirements, planning and delivery must be standardized. The latter was achieved by EIR (Exchange Information Requirements), new BIM roles, BEP (BIM Execution Plan), and specified digital handover, which must be supported by a common data environment (CDE). This paper provides an analysis of the characteristics of BIM project delivery and duration in Architectural and Engineering companies in Slovakia. The analysis is based on the web survey of BIM managers and coordinators, which reveals that a significant amount of BIM project efforts must be executed by BIM specialists. The results also graphically depict the scope of critical BIM activities across project phases. The presented study is relevant for various project stakeholders and allows for a deeper understanding of the resources needed for the successful delivery of BIM projects in terms of adequate project team capacity, capability, organization, and planning

Whole-exome sequencing of 228 patients with sporadic Parkinson's disease

Parkinson’s disease (PD) is the most common neurodegenerative movement disorder, affecting 1% of the population over 65 years characterized clinically by both motor and non-motor symptoms accompanied by the preferential loss of dopamine neurons in the substantia nigra pars compacta. Here, we sequenced the exomes of 244 Parkinson’s patients selected from the Oxford Parkinson’s Disease Centre Discovery Cohort and, after quality control, 228 exomes were available for analyses. The PD patient exomes were compared to 884 control exomes selected from the UK10K datasets. No single non-synonymous (NS) single nucleotide variant (SNV) nor any gene carrying a higher burden of NS SNVs was significantly associated with PD status after multiple-testing correction. However, significant enrichments of genes whose proteins have roles in the extracellular matrix were amongst the top 300 genes with the most significantly associated NS SNVs, while regions associated with PD by a recent Genome Wide Association (GWA) study were enriched in genes containing PD-associated NS SNVs. By examining genes within GWA regions possessing rare PD-associated SNVs, we identified RAD51B. The protein-product of RAD51B interacts with that of its paralogue RAD51, which is associated with congenital mirror movements phenotypes, a phenotype also comorbid with PD