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The transformation of cities from the industrial age (unsustainable) to the knowledge age (sustainable) is essentially a “whole life cycle” process consisting of planning, development, operation, reuse and renewal. During this transformation, a multi‐disciplinary knowledge base, created from studies and research about the built environment aspects is fundamental: historical, architectural, archeologically, environmental, social, economic, etc., and critical. Although there are a growing number of applications of 3D VR modelling applications, some built environment applications such as disaster management, environmental simulations, computer‐aided architectural design and planning require more sophisticated models beyond 3D graphical visualization such as multifunctional, interoperable, intelligent, and multi‐representational. Advanced digital mapping technologies such as 3D laser scanner technologies can be enablers for effective e‐planning, consultation and communication of users' views during the planning, design, construction and lifecycle process of the built environment. These technologies can be used to drive the productivity gains by promoting a free‐flow of information between departments, divisions, offices, and sites; and between themselves, their contractors and partners when the data captured via those technologies are processed and modelled into building information modelling (BIM). The use of these technologies is a key enabler to the creation of new approaches to the “Whole Life Cycle” process within the built and human environment for the twenty‐first century. This paper aims to look at this subject.

The paper describes the research towards BIM for existing structures via the point cloud data captured by the 3D laser scanner technology. A case study building is used to demonstrate how to produce 3D CAD models and BIM models of existing structures based on designated techniques.

The paper finds that BIM can be achieved for existing structures by modelling the data captured with 3D laser scanner from the existing world. This can be accomplished by adapting appropriate automated data processing and pattern recognition techniques through applied science research.

BMI will enable automated and fast data capture and modelling for not only in design and planning, building refurbishment, effective heritage documentation and VR modelling but also disaster management, environmental analysis, assessment and monitoring, GIS implementation, sophisticated simulation environments for different purposes such as climate change, regeneration simulation for complexity and uncertainty and so on. As a result, it will increase the capability for fast production of virtual reality models and comprehensive and sophisticated simulation platforms.

The paper provides useful information on BMI for existing structures.

Existing calibration methods mainly focus on the camera laser-plane calibration of a single laser-line length, which is not convenient and cannot guarantee the consistency of the results when several three-dimensional (3D) scanners are involved. Thus, this study aims to provide a unified step for different laser-line length calibration requirements for laser profile measurement (LPM) systems.

3D LPM is the process of converting physical objects into 3D digital models, wherein camera laser-plane calibration is critical for ensuring system precision. However, conventional calibration methods for 3D LPM typically use a calibration target to calibrate the system for a single laser-line length, which needs multiple calibration patterns and makes the procedure complicated. In this paper, a unified calibration method was proposed to automatically calibrate the camera laser-plane parameters for the LPM systems with different laser-line lengths. The authors designed an elaborate planar calibration target with different-sized rings that mounted on a motorized linear platform to calculate the laser-plane parameters of the LPM systems. Then, the camera coordinates of the control points are obtained using the intersection line between the laser line and the planar target. With a new proposed error correction model, the errors caused by hardware assembly can be corrected. To validate the proposed method, three LPM devices with different laser-line lengths are used to verify the proposed system. Experimental results show that the proposed method can calibrate the LPM systems with different laser-line lengths conveniently with standard steps.

The repeatability and accuracy of the proposed calibration prototypes were evaluated with high-precision workpieces. The experiments have shown that the proposed method is highly adaptive and can automatically calibrate the LPM system with different laser-line lengths with high accuracy.

In the repeatability experiments, there were errors in the measured heights of the test workpieces, and this is because the laser emitter had the best working distance and laser-line length.

By using this proposed method and device, the calibration of the 3D scanning laser device can be done in an automatic way.

The calibration efficiency of a laser camera device is increased.

The authors proposed a unified calibration method for LPM systems with different laser-line lengths that consist of a motorized linear joint and a calibration target with elaborately designed ring patterns; the authors realized the automatic parameter calibration.

The purpose of this paper is to present a literature review of laser scanning and 3D modelling devices, modes of delivery and applications within the architecture, engineering, construction and owner-operated sector. Such devices are inextricably linked to modern digital built environment practices, particularly when used in conjunction with as-built building information modelling (BIM) development. The research also reports upon innovative technological advancements (such as machine vision) that coalesce with 3D scanning solutions.

A synthesis of literature is used to develop: a hierarchy of the modes of delivery for laser scan devices; a thematic analysis of 3D terrestrial laser scan technology applications; and a componential cross-comparative tabulation of laser scan technology and specifications.

Findings reveal that the costly and labour intensive attributes of laser scanning devices have stimulated the development of hybrid automated and intelligent technologies to improve performance. Such developments are set to satisfy the increasing demand for digitisation of both existing and new buildings into BIM. Future work proposed will seek to: review what coalescence of digital technologies will provide an optimal and cost-effective solution to accurately re-constructing the digital built environment; conduct case studies that implement hybrid digital solutions in pragmatic facilities management scenarios to measure their performance and user satisfaction; and eliminate manual remodelling tasks (such as point cloud reconstruction) via the use of computational intelligence algorithms integral within cloud-based BIM platforms.

Although laser scanning and 3D modelling have been widely covered en passant within the literature, scant research has conducted a holistic review of the technology, its applications and future developments. This review presents concise and lucid reference guidance that will intellectually challenge, and better inform, both practitioners and researchers.

2D laser rangefinders (LRFs) are commonly used sensors in the field of robotics, as they provide accurate range measurements with high angular resolution. These sensors can be coupled with mechanical units which, by granting an additional degree of freedom to the movement of the LRF, enable the 3D perception of a scene. To be successful, this reconstruction procedure requires to evaluate with high accuracy the extrinsic transformation between the LRF and the motorized system.

In this work, a calibration procedure is proposed to evaluate this transformation. The method does not require a predefined marker (commonly used despite its numerous disadvantages), as it uses planar features in the point acquired clouds.

Qualitative inspections show that the proposed method reduces artifacts significantly, which typically appear in point clouds because of inaccurate calibrations. Furthermore, quantitative results and comparisons with a high-resolution 3D scanner demonstrate that the calibrated point cloud represents the geometries present in the scene with much higher accuracy than with the un-calibrated point cloud.

The last key point of this work is the comparison of two laser scanners: the lemonbot (authors’) and a commercial FARO scanner. Despite being almost ten times cheaper, the laser scanner was able to achieve similar results in terms of geometric accuracy.

This work describes a novel calibration technique that is easy to implement and is able to achieve accurate results. One of its key features is the use of planes to calibrate the extrinsic transformation.

Refurbishing may be the most practical approach under the low volume production. This effort aims to achieve robotic laser cladding with the main purpose of achieving maximum processing flexibility, predictably high quality, lower maintenance and operating costs. This study aims to focus on online measurement and cladding path generation toward automatic laser cladding.

Based on the specific requirements of automatic laser cladding, an approach was proposed toward an automatic laser cladding with powder injection for the refurbishment of components with free‐form surfaces. This study assessed the feasibility of integrating a non‐contact free‐form surface measurement system, an industrial robot, and an algorithm for generating cladding tool paths seamlessly.

3D laser scanning and laser cladding systems can be embedded into an existing robot motion control system. Online measurement based 3D surface reconstruction is a practical approach toward cladding tool path generation for on‐site refurbishment.

Robotic laser cladding may be a potential application by integrating other measurement devices, such as temperature sensor based monitoring system.

Refurbishing worn‐out components could have significant economic benefits. This study indicates that robotic laser cladding may potentially facilitate improved refurbishment of oversized components.

The purpose of this paper is the presentation and research of a novel robot vision system, which uses laser dynamic triangulation, to determine three-dimensional (3D) coordinates of an observed object. The previously used physical operation principle of discontinuous scanning method is substituted by continuous method. Thereby applications become possible that were previously limited by this discretization.

The previously used prototype No. 2, which uses stepping motors to realize a discontinuous laser scan, was substituted by the new developed prototype No. 3, which contains servomotors, to achieve a continuous laser scan. The new prototype possesses only half the width and turns out to be significantly smaller and therefore lighter than the old one. Furthermore, no transmissions are used, which reduce the systematic error of laser positioning and increase the system reliability.

By using a continuous laser scan method instead of discontinuous laser scan method, dead zones in the laser scanner field can be eliminated. Thereby, also by changing the physical operation principle, the implementation of applications is allowed, which previously was limited by the fixed step size or by the object distance under observation. By using servomotors instead of stepping motors, also a significant reduced positioning time can be accomplished maintaining the relative positioning error less than 1 per cent.

The originality is based on the substitution of the physical operation principle of discontinuous by continuous laser scan. The previously used stepping motors discretized the laser scanner field and thereby produced dead zones, where 3D coordinates cannot be detected. These stepping motors were substituted by servomotors to revoke these disadvantages and provide a continuous laser scan, where dead zones in the field of view get eliminated and the step response of the laser scanner accelerated.

This paper aims to describe a new optical geometrical inspection technique and its applications by Volvo Cars.

The paper discusses the limitations of contact probe‐based coordinate measurement machines scanning, describes a new, laser‐based 3D geometrical scanning system developed jointly by Metris and Volvo, Ghent, and considers its applications and benefits.

This shows that the 3D laser scanning system offers significant operational benefits over the conventional, contact probe‐based approach to geometrical inspection. It has been shown by Volvo to reduce the roll‐out time of an entire vehicle assembly process by up to ten weeks.

This paper shows how the joint development and deployment of a laser‐based 3D scanning system has speeded up and improved the geometrical inspection of car components and finished vehicles.

This paper aims to present a reverse engineering (RE) approach for three-dimensional (3D) model reconstruction and fast prototyping (FP) of broken chess pieces.

A case study involving a broken chess piece was selected to demonstrate the effectiveness of the proposed unconventional RE approach. Initially, a laser 3D scanner was used to acquire a (non-uniform rational B-spline) surface model of the object, which was then processed to develop a parametric computer aided design (CAD) model combined with geometric design and tolerancing (GD&T) technique for evaluation and then for FP of the part using a computer numerical controlled (CNC) machine.

The effectiveness of the proposed approach for reconstruction and FP of rotational parts was ascertained through a sample part. The study demonstrates non-contact data acquisition technologies such as 3D laser scanners together with RE systems can support to capture the entire part geometry that was broken/worn and developed quickly through the application of computer aided manufacturing principles and a CNC machine. The results indicate that design communication, customer involvement and FP can be efficiently accomplished by means of an integrated RE workflow combined with rapid product development tools and techniques.

This research established a RE approach for the acquisition of broken/worn part data and the development of parametric CAD models. Then, the developed 3D CAD model was inspected for accuracy by means of the GD&T approach and rapidly developed using a CNC machine. Further, the proposed RE led FP approach can provide solutions to similar industrial situations wherein agility in the product design and development process is necessary to produce physical samples and functional replacement parts for aging systems in a short turnaround time.

Computer‐aided fragmented cultural relics repair is an effective method instead of manual repair. The purpose of this paper is to provide a 3D digital patching system for computer‐aided cultural relics repair through using the scanned 3D data of fragmented cultural relics. It includes processes and tools that can be effectively used for fragmented cultural relics repair.

An automatic 3D digital patching for fragmented culture relics repair is designed. The framework includes a surface segmentation based on region dilation, feature extraction based on height‐map, pair matching and multi‐block matching.

The paper finds that the proposed 3D data patching is an efficient method for fragmented cultural relics repair.

Early and effective planning and implementation of computer‐aided fragmented cultural relics repair can significantly improve the reliability and availability of fragmented cultural relics repair.

The paper presents a uniform framework of 3D digital patching for fragmented cultural relics repair.

The purpose of this paper is to validate the accuracy of point cloud data generated from a 3D body scanner.

A female dress form was scanned with an X‐ray computed tomography (CT) system and a 3D body scanning system. The point cloud data from four axial slices of the body scan (BS) data were compared with the corresponding axial slices from the CT data. Length and cross‐sectional area measurements of each slice were computed for each scanning technique.

The point cloud data from the body scanner were accurate to at least 2.0 percent when compared with the CT data. In many cases, the length and area measurements from the two types of scans varied by less than 1.0 percent.

Only two length measurements and a cross‐sectional area measurement were compared for each axial slice, resulting in a good first attempt of validation of the BS data. Additional methods of comparison should be employed for complete validation of the data. The dress form was scanned only once with each scanning device, so little can be said about the repeatability of the results.

Accuracy of the point cloud data from the 3D body scanner indicates that the main issues for the use of body scanners as anthropometric measurement tools are those of standardization, feature locations, and positioning of the subject.

Comparisons of point cloud data from a 3D body scanner with CT data had not previously been performed, and these results indicate that the point cloud data are accurate to at least 2.0 percent.