3D Ship Modeling with Laser Scanning Method

BAR INTERNATIONAL …, 2004

Using different data capturing techniques (manual drawing, laser pen-aided drawing, MicroScribe and FaroArm drawing, adjustable 3D pin and cardboard models) the hull of a vessel is reconstructed for further manual and/or computerized analysis (I-Ship program).

ICGG2018. 18th International Conference on Geometry and Graphics, 2019

This work deals with a novel procedure that can be used for reverse engineering (RE) of big and old boats’ hull through cheap and effective instruments. The procedure has been used to acquire dimensions and shapes of an offshore boat designed by Renato Levi in 1962, named “Ultima Dea”, commissioned by Gianni Agnelli. The research purpose is the development of a method that gives to designers and restorer an “easy to use” instrument for obtaining the 2D and 3D CAD models from a degraded physical object in order to check and re-design the parts to be restored. The study and the application allowed to develop an innovative procedure to set the right acquisition parameters for optimizing the RE output in terms of minimization of maximum error and mean geometric errors between physical object and virtual model, by using a one-shot RE operation and a completely off-line post-processing. This procedure ensures good timesaving, during acquisition, very high reliability level and lightness of CAD models, also being able to reconstruct worn down and spoiled parts (through ex-novo modelling). The procedure shows how the CAD-modelling step can be done directly on graphical models (without surfaces’ mathematics) while ensuring the appropriate level of detail and, contemporarily, improving the interoperability of used and developed software. This procedure is based on the use of well-known methodologies and instruments that usually are employed in architectural relief; finally, it allowed to model the boat’s hull for the redesigning of engine/electrical/services systems and to restore the boat completely.

Measurement, 2017

Accuracy is a crucial requirement in the shipbuilding industry, especially during the design stage. The existence of errors in 3D prototype models can cause huge discrepancies when projected to full-scale objects. The ability to provide rapid and dense 3D data has made the terrestrial laser scanners (TLSs) a viable option in shipbuilding measurement. However, the numerous sources of systematic error that corrupt collected TLS data make a calibration procedure necessary. The requirement of laboratory with large number of targets to perform existing TLS calibration procedures make them unfeasible for most TLS users. Thus, this study has investigated the suitability of an onsite calibration method for application in high-accuracy shipbuilding. Two prototype boats were measured using a Faro Focus 3D scanner and close range photogrammetry was used for benchmarking purposes. By utilising four quantitative analyses, the results verify the ability of the developed calibration method to improve the accuracy of terrestrial laser scanner measurements in the field. With a relatively simple implementation, the developed calibration method is expected to be valuable for a wide variety of terrestrial laser scanner applications, especially the shipbuilding industry.

The following methodology has been developed to model and analyse the hydrostatic and hydrodynamic characteristics of a reconstructed hull. The Drogheda boat physical scale model was 3D laser scanned and processed using Geomagic Studio software. Each individual component is solid modelled using Rhinoceros 3D software and assigned a material. This enables the Orca 3D software, a plug-in for Rhinoceros 3D to calculate important factors such as centre of gravity and density and establish a floatation condition for the vessel, and examine external influences such as ballast, cargo, crew, and wind loading. Using this digital approach quickly allows for multiple variables to be tested and modified in order to reach a definitive original hull form

Proceedings of SPIE, 2005

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2011

Since 2003, Barcelona charter has highlighted the importance of digital recording of historic ships and maritime heritage in general. Despite this has been stressed with emphasis, three dimensional modelling of maritime cultural heritage is still not usual as for archaeology and architecture. Three-dimensional modelling in the maritime heritage needs particular requirements. Objects to be recorded range from small replicas in maritime museums up to full-scale vessels still in operation. High geometric accuracy, photorealism of final model and faithful rendering of salient details are usually needed, together with the classical requisites characterising the 3D modelling-from-reality process, i.e. automation, low cost, reliability and flexibility of the modelling technique. In this paper, a hybrid multi-technique approach is proposed for maritime heritage preservation and, as case study, the 3D modelling of a 3-meter-long scale model of a historic warship, the "Indomito", is presented. The survey is placed in a wider project aiming to realize the virtual maritime museum of Parthenope University of Naples, for making it available to a wider public and also preserving its cultural heritage. Preliminary results are presented and discussed, highlighting relevant aspects that emerged during the experiment.

spie.org

2005

In a 3D acquisition project range maps collected around the object to be modeled, need to be integrated. With portable range cameras these range maps are taken from unknown positions and their coordinate systems are local to the sensor. The problem of unifying all the measurements in a single reference system is solved by taking contiguous range maps with a suitable overlap level; taking one map as reference and doing a rototranslation of the adjacent ones by using an “Iterative Closest Point” (ICP) method. Depending on the 3D features over the acquired surface and on the amount of overlapping, the ICP algorithm convergence can be more or less satisfactory. Anyway it always has a random component depending on measurement uncertainty. Therefore, although each individual scan has a very good accuracy, the error’s propagation may produce deviations in the aligned set respect to real surface points. In this paper a systematic study of the different alignment modality and the consequent total metric distortions on the final model, is shown. In order to experiment these techniques a case-study of industrial interest was chosen: the 3D modeling of a boat’s hull mold. The experiments involved a triangulation based laser scanner integrated with a digital photogrammetry system. In order to check different alignment procedures, a Laser Radar capable to scan all the object surface with a single highly accurate scan, was used to create a “gold-standard” data set. All the experiments were compared with this reference and from the comparison several interesting methodological conclusions have been obtained.

2017

Accurate documentation of cultural heritage material is essential to its study and interpretation by archaeologists. In order to continually refine the documentation process, technological advances are incorporated into traditional methodologies. This study demonstrates the utility of high-definition laser scanning for the documentation of disarticulated timbers from the ship remains found during the excavation of the former site of the World Trade Center in New York City. Laser scanned models of the timbers were used to virtually reassemble the ship, produce traditional scaled drawings for standard documentation, loft a series of ship lines for reconstruction modeling, and to produce a scaled 3-D printed model of the ship.

In recent times, interest in the study of engineering structures has been on the rise as a result of improvement in the tools used for operations such as, As-built mapping, deformation studies to modeling for navigation etc. There is a need to be able to model structure in such way that accurate needed information about positions of structures, features, points and dimensions can be easily extracted without having to pay physical visits to site to obtain measurement of the various components of structures. In this project, the data acquisition system used is the terrestrial laser scanner, High Definition Surveying (HDS) equipment; the methodology employed is similar to Close Range Photogrammetry (CRP). CRP is a budding technique or field used for data acquisition in Geomatics. It is a subset of the general photogrammetry; it is often loosely tagged terrestrial photogrammetry. The terrestrial laser scanning technology is a data acquisition system similar to CRP in terms of deigning the positioning of instrument and targets, calibration, ground control point, speed of data acquisition, data processing (interior, relative and absolute orientation) and the accuracy obtainable. The aim of this project was to generate the three-dimensional model of structures in the Faculty of Engineering, University of Lagos using High Definition Surveying, the Leica Scan Station 2 HDS equipment was used along with Cyclone software for data acquisition and processing. The result was a 3D view (of point clouds) of the structure that was studied, from which features were measured from the model generated and compared with physical measurement on site. The technology of the laser scanner proved to be quite useful and reliable in generating three dimensional models without compromising accuracy and precision. The generation of the 3D models is the replica of reality of the structures with accurate dimensions and location.