Implementation of 3D Optical Scanning Technology for Automotive Applications

Reverse engineering (RE) is a powerful tool for generating a CAD model from the 3D scan data of a physical part that lacks documentation or has changed from the original CAD design of the part. The process of digitizing a part and creating a CAD model from 3D scan data is less time consuming and provides greater accuracy than manually measuring the part and designing the part from scratch in CAD. 3D optical scanning technology is one of the measurement methods which have evolved over the last few years and it is used in a wide range of areas from industrial applications to art and cultural heritage. It is also used extensively in the automotive industry for applications such as part inspections, scanning of tools without CAD definition, scanning the casting for definition of the stock (i.e. the amount of material to be removed from the surface of the castings) model for CAM programs and reverse engineering. In this study two scanning experiments of automotive applications are illustrated. The first one examines the processes from scanning to re-manufacturing the damaged sheet metal cutting die, using a 3D scanning technique and the second study compares the scanned point clouds data to 3D CAD data for inspection purposes. Furthermore, the deviations of the part holes are determined by using different lenses and scanning parameters

Image gradient based 3D roughness estimation and rendering for haptic palpation from a single skin image

Background/purpose: Skin palpation and property analysis (roughness, dryness, stiffness, temperature) are crucial for skin examination and diagnose. That is why is needed a noncontact-based method that allows to carry it out avoiding secondary infections or damage. A haptic device with haptic feedback was designed some years ago, but accurate results for 3D skin surface reconstruction and roughness estimation are still in research and improvement. In this study is proposed a gradient-based skin surface 3D roughness estimation algorithm that will enable haptic palpation and roughness examination. Methods: 3D roughness is estimated from 2D single image. First step is pre-processing the image, to improve the quality and reduce the noise by using contrast stretching and bilateral filtering. After, the gradient field is computed and used to obtain the 3D surface reconstruction using a surface-from-gradient algorithm, which will allow 3D roughness computation for a later dynamic haptic rendering. Results: Texture and curvature of the 3D reconstructed surface are checked in the first experiment, comparing roughness and geometry errors between a reconstructed surface using the proposed algorithm and two other algorithms, as well with a ground truth surface. The second experiment tests the method using in-vivo real skin disease images to compute roughness estimation and decomposition and also tasting haptic rendering in a haptic device. The experimental results verify the validity of our method. Conclusion: Roughness is a crucial property for dermatologists to examine skin disease (e.g., cases of psoriasis, atopic eczema or aging), that is why the proposed method of roughness estimation for haptic rendering will be extremely useful for dermatologists, improving the skin diagnose. In addition, the proposed method does not require complex medical systems to be implemented, since single image reconstruction is used.Outgoin

Reverse Engineering Body Fender Mobil Esemka Rajawali Ii Dengan Membandingkan Hasil Pengukuran Menggunakan Coordinate Measuring Manual Machine Dan Laser Scanner Articulated Measurement Arms

This research uses reverse engineering method which aims to get 3D surface fender images of Esemka Rajawali II car and compare the result of fender measurement by using two steps of measurement (scanning). The first step is the measurement on the Esemka Rajawali II car fender using a manual 3D measuring instrument, while the second step is the measurement of Esemka Rajawali II car fender using 3D Laser Scanner Articulated Measurement Arms (LSAMA). Data obtained from the above point of coordinates (point cloud) x, y and z, which then the data point coordinates are inserted into softwere solidworks to create images of 3D fender part of the car surface esemka Rajawali II. After the process of making a 3D part surface fender image completed, the next stage compares the results of the two measuring instruments. The point (coordinate) of the fender component is the assist point used to explain the shape of the surface of the fender. The number of points used will affect the shape of the resulting fender, it is caused between the point one or the other point connected through the line before the surface on softwere solidworks. The number of points and the location of the point is randomly assigned to the fender component. Of the two measuring tools are 3D (LSAMA) and manual 3D measuring instruments, using the same number of koodinat points. Using 3D (LSAMA) has a better measurement precision than a manual 3D measuring instrument

Pre-Processing of Point-Data from Contact and Optical 3D Digitization Sensors

Contemporary 3D digitization systems employed by reverse engineering (RE) feature ever-growing scanning speeds with the ability to generate large quantity of points in a unit of time. Although advantageous for the quality and efficiency of RE modelling, the huge number of point datas can turn into a serious practical problem, later on, when the CAD model is generated. In addition, 3D digitization processes are very often plagued by measuring errors, which can be attributed to the very nature of measuring systems, various characteristics of the digitized objects and subjective errors by the operator, which also contribute to problems in the CAD model generation process. This paper presents an integral system for the pre-processing of point data, i.e., filtering, smoothing and reduction, based on a cross-sectional RE approach. In the course of the proposed system development, major emphasis was placed on the module for point data reduction, which was designed according to a novel approach with integrated deviation analysis and fuzzy logic reasoning. The developed system was verified through its application on three case studies, on point data from objects of versatile geometries obtained by contact and laser 3D digitization systems. The obtained results demonstrate the effectiveness of the system

Escáneres ópticos 3D de mano en ingeniería inversa

Data acquisition is a key part in any reverse engineering process. When measuring mechanical components, or any physical object, there are numerous methods to perform this phase, but handheld 3D scanners are among the most popular. Compared to static scanners, handheld scanners have the advantage of being easier to transport and use. The present article contains a brief description of reverse engineering and an analysis of the three technologies that make handheld 3D scanners possible. Examples of the most innovative devices within each category are included and the positioning methods of optical 3D scanners are discussed.This article aims to bring together the latest information on handheld optical scanners and their technologies in order to facilitate the choice of the most suitable method for each application.Una parte fundamental en cualquier proceso de ingeniería inversa es la adquisición de datos.En el caso de componentes mecánicos o, en general, de cualquier objeto físico, existen numerosos métodos y herramientas para abordar dicha fase, entre los que destacan los escáneres ópticos 3D de mano. En comparación con los escáneres estáticos, los escáneres de mano tienen la ventaja de ser más fáciles tanto de transportar como de utilizar. En este documento, tras una breve descripción del proceso de ingeniería inversa, se profundiza en la fase de adquisición de datos y, concretamente, en las tres tecnologías en las que basan su funcionamiento los escáneres ópticos 3D de mano. Además, se incluyen ejemplos de los dispositivos más innovadores dentro de cada categoría y se abordan los métodos de posicionamiento de los escáneres ópticos 3D

Increasing the reliability of data collection of laser line triangulation sensor by proper placement of the sensor

In this paper, we investigated the effect of the incidence angle of a laser ray on the reflected laser intensity. A dataset on this dependence is presented for materials usually used in the industry, such as transparent and non-transparent plastics and aluminum alloys with different surface roughness. The measurements have been performed with a laser line triangulation sensor and a UR10e robot. The presented results are proposing where to place the sensor relative to the scanned object, thus increasing the reliability of the sensor data collection.Web of Science218art. no. 289

Wear Analysis of Die Inserts in the Hot Forging Process of a Forked Type Forging Using Reverse Scanning Techniques

This article presents a wear analysis of die inserts used in the hot forging process of a forked forging (yoke), an element applied in steering systems of passenger vehicles. Studies involved the application of an original reverse scanning method intended for rapid and reliable wear analysis of forging tools (with complicated shape) affording easy assessment without the need to dismount tools from the forging unit. The developed method involves analysis of progressive wear of forging tools based on measurements (scanning) of forgings periodically collected from the process and constitutes a useful tool for measurement and testing. As the authors’ earlier works have demonstrated, the proposed new approach to analysis of tool wear with the application of reverse 3D scanning has proven successful in multiple instances in the case of axially symmetrical objects. The presented results of studies indicate that it is possible to utilize the expanded method to analyze the lifetime of forging tools, including tools with complex geometry. Application of the reverse scanning method allows for continuous and practical monitoring of the condition of forging tools over the course of the forging process and should have a positive impact on improving production output and reducing production costs

Application of 3D modeling in automotive industry

U ovom završnom radu prikazan je kompletan proces izrade automobila u programu Autodesk Maya. Autodesk Maya jedan je od vodećih alata za modeliranje te u kombinaciji s drugim programima daje bezbroj mogućnosti u svijetu 3D-a. 3D se u automobilskoj industriji počinje koristiti sve više, pa se tako upotrebljava u promotivne svrhe kao i za aplikacije s proširenom stvarnošću. Isto tako, velik dio 3D modeliranja u industriji automobila zauzima i „reverse engineering“ koji nam omogućuje da stvorimo zamjenske dijelove za naš automobil. Prilikom izrade modela automobila korišteno je poligonalno modeliranje te gotovi materijali renderera Redshift-a. Za renderiranje projekta korišten je renderer Redshift zbog prednosti renderiranja pomoću jedinica grafičke kartice. Ta prednost omogućuje nam renderiranje zahtjevnijih projekata u veoma kratkom vremenskom periodu. U teoretskom djelu rada objašnjena je primjena 3D modeliranja u industriji automobila te sam program za izradu modela, a praktični dio rada bazira se na prikazu kompletnog procesa izrade modela automobila za promotivne svrhe. U praktičnom dijelu prikazano je modeliranje, teksturiranje te renderiranje automobila.In this final paper it is shown the whole process of creating model of a car in Autodesk Maya. This program is one of the leading tools in modeling and combined with others programs gives us a endless amount of options. 3D modeling is being used more often in automotive industry therefore it is used in promotional purpose and for augmented reality applications. Big part of ad modeling in automotive industry is reverse engineering which allows us to create spare parts for our car. Polygonal modeling is used to create a 3D model of a car. Redshift was used for rendering because it allows us to render with graphic card units. This advantage allows us to render complex projects in very short period of a time. Applications of 3D modeling in automotive industry and program used for modeling are explained in the theoretical part. The whole process of creating a model car is shown in the practical part that can be used later in promotional purpose. Also it is shown the process of modeling, texturing and rendering the car model

Surface damage evaluation of honeycomb sandwich aircraft panels using 3D scanning technology

A 3D scanning method is proposed for the measurement of surface damage on aircraft structural panels. Dent depth measurements were shown to be within 0.04 ± 0.06 mm (95%) of those taken using a Starrett 643J dial depth gauge based on 54 flat panel dents, and 0.04 ± 0.05 mm (95%) based on 74 curved panel dents. Dent depths were quantified by the difference between a point cloud rendering of the damaged surface and a surface fit approximating the original, undamaged surface. Convergence studies were used to evaluate the accuracy of the surface fit, enabling this technique to be used as a stand-alone inspection method. Image processing was used to measure dent length and area, and the results showed that this method is more efficient and reliable compared to manual methods. This novel non-destructive evaluation technique thus demonstrates potential to enable the timely extraction of surface dent measurements during on-site aircraft inspections

3D Scanning and computer-aided tolerance software analysis for product inspection

Tolerances are vital for every physical product, with a tight connection and competing needs between engineering design and manufacturing. 1D, 2D and 3D tolerance analysis can be applied to any product for determining these tolerances. With increase in dimensions the difficulty of tolerance analysis also increases. This research explores tolerance analysis in 3D situation. 3D scanning is a recently developed technology. In the industrial field, this technology is popular for inspecting product quality and in reverse engineering. It compares the dimensions between the 3D scanning model and the CAD model to inspect product quality. It also can generate a CAD model out of the 3D scanning model used in reverse engineering. The device mainly used in 3D scanning is the 3D optical scanner and the 3D laser scanner. These two types of 3D scanner use the same triangulation principle but one uses optical light and the other laser light. This research includes a 3D tolerance analysis and 3D scan. Before tolerance analysis a tolerance stack-up analysis was completed. Tolerance analysis was done using Crystal Ball software. The software uses Monte Carlo simulation to get results based on HTM calculator in Excel. HTM calculator contains every transformation nominal position and tolerance value. HTM calculated nominal position distance should be the same as CAD software Creo measured distance. Transformation nominal position was based on a loop diagram. Tolerance value was based on the defined tolerance in drawing and 3D scanning value. 3D scanning in this research is used to inspect product quality. Both parts and the assembly device were scanned. Parts were selected based on the loop diagram. The device was assembled using 3D scanning parts. The results of the tolerance analysis were shown through distribution charts and sensitivity charts. Comparing the simulation results of 3D scanning data and defined tolerances in drawing, distribution charts results were not reliable but sensitivity charts results were similar. The results of 3D scanning measurement data show the current device tolerance value is too tight. 3D scanning devices used in this research are not suited for large scale implementation, e.g. in product inspection