Reverse Engineering System Research Articles

Towards computer-aided reverse engineering of heavy vehicle parts using laser range imaging techniques

We present an integrated system to automatically generate computer-aided design (CAD) models of existing vehicle parts using laser range imaging techniques. The proposed system integrates data acquisition, model reconstruction, and post processing to generate a set of models from real-world automotive parts. This range image-based, computer-aided reverse engineering (CARE) system has potential for faster model reconstruction over traditional reverse engineering technologies. As part of this system, we also propose a novel crease detection algorithm, which segments the surfaces of reconstructed models along smoothness discontinuities. We present results for both the CARE system and the proposed crease detection algorithm for a set of automotive parts.

STEP-based product modeling system for remote collaborative reverse engineering

Production of high-quality products with lower cost and shorter time-to-market is an important challenge in the face of increased global competition, and reverse engineering plays an important role in accelerating product and process development. With the advent of new technologies such as network, multimedia and product data exchange standard STEP (STandard for Exchange of Product model data), there are many advantages to adopt these technologies to enhance the competitiveness of an enterprise. In this paper, a product information recording module for reverse engineering is developed to enhance the performance of product development. A STEP development tool, ST-Developer, and Visual C++ were used to develop this module, which can be used to record key information expeditiously during a collaborative process, and can also be used for further exchange of information, or as the basis for manufacturability evaluation. In this paper, the developed STEP-based information recording system is further integrated with the conventional Computer Supported Cooperative Work methods such as videoconferencing and application-sharing to form a remote collaborative reverse engineering system, which can provides a new strategy for an enterprise to speed up the product development cycle, reducing production cost, as well as sharing knowledge and experience.

Laser‐based imaging for reverse engineering

In this paper, we explore the technical challenges to automatically generate computer‐aided design models of existing vehicle parts using laser range imaging techniques. We propose a complete system that integrates data acquisition and model reconstruction. We discuss methods to resolve the occlusion problem and the associated registration problem. We also present our reconstruction algorithm. This range image‐based, computer‐aided reverse engineering system has a potential for faster model reconstruction over traditional reverse engineering technologies. Finally, we present results derived from the system.

역설계를 위한 인터넷 기반의 치수검증 시스템

In the 21st century, the concept of remote design and manufacture is strongly required in manufacturing processes to reduce cost and time-to-market.The objective of this paper is the development of an internet-based dimensional verification system for reverse engineering. An inspection client can register measurement data at the developed web server. Collaborators related to the development of a new product can confirm geometrical form from measurement data,check dimensional information and mark up the important parts,as well as make a statement of their views through the Internet.The developed system is realized through the ActiveX-Server architecture. Functions of the dimensional verification module are constructed as ActiveX by using the visual C++and OpenGL. The usefulness of the developed system is confirmed through a case study

Telemanufacturing of reverse engineered parts: A case study

A product idea is normally transferred between designers and/or manufacturing engineers using digital models. Engineering analyses are directly connected with the presence of these models and only limited to virtual evaluations. For this reason, the use of real prototypes is very important in the first design stage in order to perform a deeper product evaluation. A very attractive way to update product designs while realizing prototypes is offered by the direct data communication between reverse engineering (RE) and rapid prototyping (RP). In this way the reproduction of aesthetic prototypes in different geographical positions becomes a key factor for successful competition. In this article, the authors investigate the efficiency of the data transfer between RE and RP systems in order to speed up product development without sharing design intent. A specialized software tool is described in order to perform product shape acquisition, elimination of redundant point cloud data, retriangulation of the point cloud and generation of a machine file for RP fabrication.

Automated laser scanning system for reverse engineering and inspection

Recently, laser scanners have been used more often for inspection and reverse engineering in industry, such as for motors, electronic products, dies and molds. However, due to the lack of efficient scanning software, laser scanners are usually manually operated. Therefore, the tasks that involve inspection and reverse engineering processes are very expensive. In this research, we propose an automated measuring system for parts having a freeform surface. In order to automate a measuring process, appropriate hardware system as well as software modules are required. The hardware system consists of a laser scanning device and setup fixtures that can provide proper location and orientation for the part to be measured. The software modules generate optimal scan plans so that the scanning operation can be performed accordingly. In the scan planning step, various scanning parameters are considered in the generation of optimal scan paths, such as the view angle, depth of field, the length of the stripe, and occlusion. In the scanning step, the generated scan plans are downloaded to the industrial laser scanner and the point data are captured automatically. The measured point data sets are registered automatically and the quality of point data is evaluated by checking the difference between the CAD model and the measured data. To demonstrate an automated measuring system, a motorized rotary table with two degrees of freedom and a CNC-type laser scanner with four degrees of freedom are used.

Automated segmentation of point data in a feature-based reverse engineering system

This paper proposes a novel methodology for robust segmentation of scanned point data that has been implemented in the feature-based reverse engineering system (FBRES). In the proposed method, firstly triangle meshes are generated from the input point data. The normal and the area of generated meshes are checked to find boundary meshes using the angle deviation criterion and the area criterion based upon a region-growing technique. Boundary meshes of each segmented region are connected into loops. Then, the meshes closed by each boundary loop are segmented into a single distinctive region. Finally, all segmented regions are mapped into a single feature using an artificial neural network (ANN) based feature recognizer. The FBRES is currently dedicated for reconstructing prismatic features such as a block, pocket, step, slot, hole and boss, which are very common and crucial in mechanical engineering products. The effectiveness of the proposed segmentation method is validated with experimental results.

Development of an Integrated Laser-Based Reverse Engineering and Machining System

Reverse engineering technology plays an important role in a variety of manufacturing applications. It significantly reduces the production lead time and the costs of the part duplication processes. This paper evaluates the feasibility of using reverse engineering and concurrent engineering methods with data obtained from state-of-the-art laser scanning to remanufacture complex geometrical parts. Two aircraft structural components were evaluated in this study: a forward latch fitting of a C 141 and a leading edge rib of an F-15. The first phase of this project, accuracy characterisation of a reverse engineering system, demonstrated that laser scanning and CAD model reconstruction can duplicate aircraft structural components accurately and efficiently, within a tolerance of ±0.127 mm (0.005 in). The second phase of this project, development of a concurrent engineering system, showed that an integrated reverse engineering and CAM machining system can make the entire remanufacturing process snore automatic and efficient, further reducing part turnaround time.

3-D imaging and modeling – Part II: integration and duplication

Summary One of the key modules in a typical reverse engineering system is the integration of multiple range images of three-dimensional objects with complex geometry. In the Part I of this article [1], we have presented a self- made optical digitizer that is employed for quickly acquiring range data of the objects from multiple views, and introduced a visualized registration procedure that can provide a reliable estimate for the fine registration of multiple range images in a unified coordinate system. Here we propose a new approach for merging multiple range images to build up a complete geometric model of the objects in 3-D space. This approach is based on the segmentation of a pair of range images using the concepts of “double stitching lines”, as well as a constrained local triangulation process. Experiment results are presented to show the effectiveness of this approach in 3-D imaging and modeling for the applications of reverse engineering.

A rapid reverse engineering system for reproducing 3D human busts

The most critical problems in the current reverse engineering (RE) are often related to data registration and hole filling. This is because no single scan image is sufficient to describe the entire object since most objects occlude themselves, and some scanned data is likely to be missing on the object. In this paper, we establish a registration and a hole-filling algorithm to solve this problem. The registration module is based upon the standard Iterative Closest Point (ICP) algorithm with some additional heuristics, which help to overcome the limitation of ICP requiring that one of the data scans must be a subset of the other. The aligned triangle mesh is still unsuitable for model reproduction since it often has missing data. The proposed hole filling algorithm reconstructs these missing data with the iterative manner and these data are then smoothed with their neighboring polygonal meshes. We have developed a dedicated system for reproducing a human head and shoulder by using the implemented polygon-based algorithms. The system quickly reconstructs the surface datails of human busts and produces the replica of 3D human model using 4-axis CNC milling machine. Some typical examples are presented to validate the system and further research work is also discussed.

3-D imaging and modeling – Part I: acquisition and registration

The key modules in a typical reverse engineering system consist of the acquisition, registration, and the integration of range images of three-dimensional objects with complex geometry. We first present a self-made optical digitizer that is employed for quickly acquiring range data from multiple views, then introduce a visualized registration procedure that can provide a reliable estimate for the fine registration of multiple range images in a unified coordinate system. Experiment results are given to show the effectiveness of this approach in 3-D imaging and multiple range image registration for the applications of reverse engineering.

3-D imaging and modeling – Part I: acquisition and registration

The key modules in a typical reverse engineering system consist of the acquisition, registration, and the integration of range images of three-dimensional objects with complex geometry. We first present a self-made optical digitizer that is employed for quickly acquiring range data from multiple views, then introduce a visualized registration procedure that can provide a reliable estimate for the fine registration of multiple range images in a unified coordinate system. Experiment results are given to show the effectiveness of this approach in 3-D imaging and multiple range image registration for the applications of reverse engineering.

A reverse engineering system for rapid manufacturing of complex objects

This paper presents a reverse engineering system for rapid modeling and manufacturing of products with complex surfaces. The system consists of three main components: a 3D optical digitizing system, a surface reconstruction software and a rapid prototyping machine. The unique features of the 3D optical digitizing system include the use of white-light source, and cost-effective and quick image acquisition. The surface reconstruction process consists of three major steps: (1) range view registration by an iterative closed-form solution, (2) range surface integration by reconstructing an implicit function to update the volumetric grid, and (3) iso-surface extraction by the Marching Cubes algorithm. The modeling software exports models in STL format, which are used as input to an FDM 2000 machine to manufacture products. The examples are included to illustrate the systems and the methods.

APPROXIMATE GEOMETRIC REGULARITIES

Current reverse engineering systems are able to generate simple valid boundary representation (B-rep) models from 3D range data. Such models suffer from various inaccuracies caused by noise in the input data and algorithms. Reverse engineered geometric models may be beautified by finding approximate geometric regularities in such a model, and imposing a suitable subset of them on the model by using constraints. Methods to detect suitable regularities for the beautification of B-rep models having only planar, spherical, cylindrical, conical and toroidal faces are presented in this paper. The regularities are described in terms of similarities. Different properties of faces, edges and vertices, and small groups of these elements in a B-rep model are represented as feature objects. Similar feature objects, such as directions which are parallel, form one sort of regularities. For each group of similar feature objects, special feature objects which might represent the group form further regularities, e.g. an integer value which approximates the radius of similar cylinders. Further regularities arise from symmetries of feature object sets. Experiments show that the regularities found are suitable for beautification such that subsequent steps allow the selection of a consistent regularity set.

Finding Approximate Shape Regularities for Reverse Engineering

Current reverse engineering systems can generate boundary representation (B-rep) models from 3D range data. Such models suffer from inaccuracies caused by noise in the input data and algorithms. The quality of reverse engineered geometric models can be improved by finding candidate shape regularities in such a model, and constraining the model to meet a suitable subset of them, in a post-processing step called beautification. This paper discusses algorithms to detect such approximate regularities in terms of similarities between feature objects describing properties of faces, edges and vertices, and small groups of these elements in a B-rep model with only planar, spherical, cylindrical, conical and toroidal faces. For each group of similar feature objects they also seek special feature objects which may represent the group, e.g. an integer value which approximates the radius of similar cylinders. Experiments show that the regularities found by the algorithms include the desired regularities as well as spurious regularities, which can be limited by an appropriate choice of tolerances.

A study of a reverse engineering system based on vision sensor for free-form surfaces

Reverse engineering can quickly create a CAD model of a new product, in which, the sensor, sampling planning and surface reconstruction are three crucial elements. In this paper, a reverse engineering system involving a new vision sensor, an improved sampling planning module and a fine surface reconstruction module is developed. A characteristic of the proposed sensor is strong linearity between output and input, obtained by the structure optimization when a simple lens replaces the asperic lens. Back propagation (BP) neural network error compensation heightens accuracy. To increase efficiency of digitization, an improved sampling planning approach is proposed; it is based on surface curvature and tangent line slope of a measured point. In surface reconstruction, a new adaptive extracting approach based on curvature of surface reconstructs the non-uniform rational B-spline (NURBS) surface for the scattered data. The accompanying reverse engineering experiment proves the proposed system to be reliable and efficient.

Research on integrated reverse engineering technology for forming sheet metal with a freeform surface

This paper presents a model of an integrated reverse engineering system and sets up its various-data-output flowchart, which is easily associated with other systems. The ideal of integrated reverse engineering is introduced to the system of forming sheet metal with a complex surface, and using the IDEF0 method sets up the function model of the system. The freeform surface reconstruction and CAD modeling of the system are described and discussed. This paper discusses some problems, such as the feature expression, feature modeling and feature translation of the sheet parts and dies.

A multi-sensor approach to automating co-ordinate measuring machine-based reverse engineering

Co-ordinate measuring machines (CMMs) have been widely used in industry for reverse engineering. In an ideal reverse engineering system, the object would be automatically digitised, the data would be segmented into constituent surface patches, and an accurate solid model would be generated. However, at present, the time-consuming manual digitisation of many objects discourages the implementation of reverse engineering. As a major step toward attaining this goal, a charged coupled device (CCD) camera and a CMM touch probe digitiser are used together in a novel reverse engineering process. Neural network based stereo image processing is used to locate the object in the CMM work space, and to generate the CMM touch probe path. Precise data is then collected using the CMM touch probe, from which a CAD/CAM model can be constructed.

Practical data exchange for reverse engineering frameworks

Reverse engineering systems hold great promise in aiding developers regain control over long-lived software projects whose architecture has been allowed to "drift". However, it is well known that these systems have relative strengths and weaknesses, and to date relatively little work has been done on integrating various subtools within other reverse engineering systems. The design of a common interchange format for data used by reverse engineering tools is therefore of critical importance.In this position paper, we describe some of our previous work with TAXFORM (Tuple Attribute eXchange FORMat) [2,6], and in integrating various "fact extractors" into the PBS reverse engineering system. For example, we have recently created translation mechanisms that enable the Acacia system's C and C++ extractors to be used within PBS, and we have used these mechanisms to create software architecture models of two large software systems: the Mozilla web browser (2.2 MLOC of C++ and C) and the VIM text editor (150 KLOC of C) [6]. We also describe our requirements for an exchange format for reverse engineering tools and some problems that must be resolved.

The development of an active computer vision system for reverse engineering

A research project is described on the development of an active computer vision system for automatically producing three-dimensional models of physical objects. The objective is to meet the increasing demand for such models for reverse engineering and computer graphics purposes. The system under development uses a camera mounted on a gantry robot arm to view an object placed on a turntable from any desired angle or position. An occluding contour technique is described which is employed by the system to generate three-dimensional data. Examples are presented of the type of model that the system can produce and current work that will further enhance the performance of the system is reviewed.