Sanguk Cheon

• Ajou University

Integration of heterogeneous computer-aided design (CAD) models into shipbuilding CAD systems is necessary during ship modeling in shipyards. Vendor package models provided by equipment vendors were designed using mechanical CAD systems. Complex triangular meshes severely affect the modeling performance of shipbuilding CAD systems. Particularly, re...

Recently, studies applying deep learning technology to recognize the machining feature of three-dimensional (3D) computer-aided design (CAD) models are increasing. Since the direct utilization of boundary representation (B-rep) models as input data for neural networks in terms of data structure is difficult, B-rep models are generally converted int...

Manufacturability validation refers to activities to evaluate the manufacturing cost of parts, manufacturing methods, and manufacturing difficulty, and to determine whether parts can be manufactured from three-dimensional (3D) computer-aided design (CAD) models. To automate the manufacturability evaluation process, it is important to first recogniz...

The acquisition of point clouds with a 3D scanner often yields large-scale, irregular, and unordered raw data, which hinders the classification of objects from these data. Some studies have introduced a method of applying the point clouds to convolutional neural networks (CNNs). This is achieved after preprocessing the volume metrics or multi-view...

On-machine measurement (OMM), which is used to measure the machined surfaces of a workpiece during or after the machining of the workpiece, enables direct measurement within the workspace without moving the workpiece. However, although the three-dimensional geometric shape created by computer-aided design systems include various features, because s...

In an offshore plant construction project, engineering, procurement, and construction (EPC) companies need to deliver plant design results to the owner in the form of a plant 3D computer-aided design (CAD) model as specified in the contract. However, owing to the limited data interface of plant 3D CAD systems, EPC companies frequently perform manua...

Diverse stakeholders engaged in design, construction, and operation and maintenance of offshore plants typically operate heterogeneous plant 3D CAD systems. Engineering, procurement, and construction (EPC) companies are required to submit plant design result to the owner in the form of a plant 3D CAD model, as specified in the contract. However, be...

When a plant owner requests plant 3D CAD models in the format that a shipbuilding company does not use, the shipyard manually re-models plant 3D CAD models according to the owner`s requirement. Therefore, it is important to develop a technology to compare the re-modeled plant 3D CAD models with original ones and to quantitatively evaluate similarit...

Because of manufacturing and assembly errors in the geometric parameters of parallel robots, calibrating the parameters is necessary for improving the positioning accuracy. The objective of this study is a 3-DOF secondary mirror of the giant Magellan telescope, which is operated by a 3-DOF parallel robot. In this paper, a kinematic calibration meth...

We introduce a method for designing manufacturing shapes for the structural parts of a ship that considers the weld-induced deformation. In this study, the design shape of a bracket was counter-deformed using a purely geometric method rather than a thermo-elastic method. The deformation quantities were estimated based on data captured in the field,...

At shipyards, to enable design cooperation with engineering companies or to meet ship owner`s requirements, there is a need to translate ship models from one ship CAD system to another ship CAD system. In this paper, a method for translating pipe models from Aveva Marine to SmartMarine3D is introduced. Related data and architecture of translation s...

A method of designing a manufacturing shape of ship plate parts considering welding deformation is introduced. In this paper, the design shape of a bracket is deformed not by a thermoelastic method but by a pure geometric method. Deformation quantities are estimated based on data captured in the field and then a manufacturing design shape is obtain...

Introduction of PLM in domestic shipyards is being retarded as ship PLM has yet to firm up return of investment and process integration. To implement a ship PLM system, it is required to share ship CAD model data in various design and manufacturing environments. Lightweight CAD models provide a promising solution for sharing CAD models in the produ...

In shipbuilding, 2D manufacturing drawings are crucial for building a ship. Even various types of 3D models are being utilized for supporting ship manufacturing, which does not reduce the importance of 2D drawings. Recently things are changing in the shipbuilding industry. To reduce the number of 2D drawings or to reduce the quantity of information...

Procedural models have the advantage of being easy to edit simply by changing the values of the parameters of their constructional operations. In previous studies, we have introduced an approach for representing procedural 2D CAD models in ISO 10303 and developed ISO 10303-112 for the exchange of procedural 2D CAD models. In this paper, a method fo...

A feature is generated by referring to topological entities in a solid model. It is essential to persistently name the topological entities referenced by the feature. This problem is known as the persistent naming problem. The persistent naming problem is divided into naming and name matching. The persistent naming problem is an important issue in...

In the concept development phase, a designer wants to rapidly create a product’s overall shape and user interfaces by making simple sketches, known as ‘thumbnail sketches’, to evaluate ideas and possibilities. Free-hand 2D sketch systems are regarded as a computerized tool for making thumbnail sketches. After the concept development phase, subseque...

This paper presents a method for reconstructing a 3D model from a freehand sketch. There are two methods used in sketch-based modeling research: gestural modeling and reconstructional modeling. This research involves the reconstructional modeling method of Mitani, which was originally designed for a box-shaped model using a predefined template. Her...

Research that reconstructs a 3D model from a freehand 2D sketch has gained attention since 1990s, when data integration in the CAD/CAPP/CAM/CNC chain was an important issue. However, 2D sketches in the conceptual design phase have not been integrated with the downstream CAD/CAPP/CAM/CNC chain. In this paper, we present a method to interface a freeh...

Digital CAD models are one of the most important assets the manufacturer holds. The trend toward concurrent engineering and outsourcing in the distributed development and manufacturing environment has elevated the importance of high quality CAD model and its efficient exchange. But designers have spent a great deal of their time repairing CAD model...

STEP-NC (formalized as ISO 14649 and ISO 10303 AP238) is a new interface (or language) standard for the CAD–CAM–CNC chain, currently under establishment by ISO TC184 SC1 and SC4. Upon completion, it will replace ISO 6983, so called M & G codes used for CNC since 1950s. As the new language is being established, a new CNC controller called STEP-CNC (...

STEP-compliant CNC is the next-generation CNC controller, taking the STEP-NC data model as the interface scheme between CAM and CNC and carrying out various intelligent functions. At the moment, efforts are being made worldwide to establish an international standard for the new interface scheme (so-called STEP-NC), formalized as ISO 14649. In the n...

In this paper, we present a conceptual framework for designing and implementing an intelligent CNC system. The architecture and functional modules are derived from requirement analysis, and they are designed to have a thinking capability before, during, and after the execution of the manufacturing task, so that the assigned task can be effectively...

Virtual manufacturing (VM) is a key concept that summarizes computerized manufacturing activities dealing with models and simulation instead of objects and their operation in the real world. In terms of manufacturing education, virtual concept is expected to be more safety, relevant and cost- effective than physical one. In this paper, we give a br...

As the networks connect the world, enterprises tend to move manufacturing activities into virtual spaces. Since different software applications use different data terminology, it becomes a problem to interoperate, interchange, and manage electronic data among heterogeneous systems. According to RTI, approximately one billion dollar has been being s...