• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.3
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• pp.83-91
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• 1999

In this paper, we suggest a virtual machining system that can simulate cutting forces of ball end milling at the stage of part design. Cutting forces, here, are estimated from the machanistic model that uses the concept of specific cutting farce coefficient. To this end, we need undeformed chip thickness which is used for calculating chip load. It is derived from the Z-map data of a CAD model. That is, chip load is the height difference between the cutting tool and the workpiece at an arbitrary position. The tool contact point is referred from the cutter location data. On the other hand, the workpiece height is acquired from the Z-map model of a CAD data. From the experimental verification, we can simulate machining process effectively to the slot and the side cutting of ball end mill.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.942-946
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• 1997

In this research,we suggest a virtual machining system that can simulate sutting forces at the stage of design. Cutting forces,here, are modeled form the machanistic model of the ball end milling. To this end, we need undeformed chip thickness which is used for calculating chip load. It is derived form the z-map data of a CAD model. That is, chip load is the height difference between the cutting tool contact point and the workpiece at arbitrary position. The tool contact point is referred from the cutter location. Form the experimental verification, we can simulate machining process effectively to the slot and the side cutting of ball end mill.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.86-92
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• 2002

This paper presents a new model of NC verification in NC milling using z-map. The model can describe the motion of machine tool like a real machine effectively. The model uses x, y, and z directional feed rate as well as cutting data for modeling Z-map of workpiece. The model verifies the over-cut, the under-cut and the surface topography using NC codes and cutting conditions. To investigate the performance of the model, simulation study was carried out. As the results, the model gave the geometry accuracy of workpiece, the surface topography, and the chip loads.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.80-85
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• 2001

In Part 2, dynamic cutting force model, thermal behavior model, and feed drive model are presented for development of a virtual machine tool. Some relevant results with brief descriptions for each model are presented to verify the proposed models. Experimental results for each model agreed well with the estimated ones. The developed models in this two-part paper are partially integrated as a comprehensive software environment.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.9
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• pp.960-966
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• 2007

High-efficient machining, which means to machine a part in the least amount of time, is the most effective tool to improve productivity. In this study, a new feed optimization method based on virtual manufacturing was proposed to realize the high-efficient machining in turning process through the cutting power regulation. The cutting area was evaluated by using the Boolean intersection operation between the cutting tool and workpiece. And the cutting force and power were predicted from the cutting parameters such as feed, depth of cut, spindle speed, specific cutting force, and so on. Especially, the reliability of the proposed optimization method was validated by comparing the predicted and measured cutting forces. The simulation results showed that the proposed optimization method could effectively enhance the productivity in turning process.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.74-79
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• 2001

In this two-part paper, a virtual machine tool (VMT) is presented. In part 1, the analytical foundation of a virtual machining system, envisioned as the foundation for a comprehensive simulation environment capable of predicting the outcome of cutting processes, is developed. The VMT system purposes to experience the pseudo-real machining before real cutting with a CNC machine tool, to provide the proper cutting conditions for process planners, and to compensate or control the machining process in terms of the productivity and attributes of products. The attributes can be characterized with the machined surface error, dimensional accuracy, roughness, integrity and so forth. The main components of the VMT are cutting process, application, thermal behavior and feed drive modules. In part 1, the cutting process module is presented. The proposed models were verified experimentally and gave significantly better prediction results than any other method. The thermal behavior and feed drive modules are developed in part 2 paper. The developed models are integrated as a comprehensive software environment in part 2 paper.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.107-112
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• 2015

Increased productivity and cost reduction have emerged as the main goals of the industry due to the development of the machinery industry, and mechanical materials with excellent properties with the development of the machine tool industry are widely used in machine parts or structures. In addition, the cutting process of production plays a pivotal role in the production technology. Studies on cutting have involved a lot of research on the material, the cutting tool, the processing conditions, and numerical analysis. Due to the development of the computer through numerical analysis, cutting conditions, the assessment of cutting performance, and cutting quality could be predicted. This research uses the creation of the material model and AdvantEdge Production module for the NC code analysis. To improve the productivity, this research employs the optimization method to reduce cutting time.

• Smart Media Journal
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• v.1 no.3
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• pp.29-35
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• 2012

A depth image-based rendering (DIBR) technique is one of the rendering processes of virtual views with a color image and the corresponding depth map. The most important issue of DIBR is that the virtual view has no information at newly exposed areas, so called dis-occlusion. In this paper, we propose an intermediate view generation algorithm using the Kinect depth camera that utilizes the infrared structured light. After we capture a color image and its corresponding depth map, we pre-process the depth map. The pre-processed depth map is warped to the virtual viewpoint and filtered by median filtering to reduce the truncation error. Then, the color image is back-projected to the virtual viewpoint using the warped depth map. In order to fill out the remaining holes caused by dis-occlusion, we perform a background-based image in-painting operation. Finally, we obtain the synthesized image without any dis-occlusion. From experimental results, we have shown that the proposed algorithm generated very natural images in real-time.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.438-441
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• 2011

가상현실기반 충치치료 훈련 시스템에서 필수적으로 구현되어야 하는 부문은 절삭도구인 버(bur)를 이용하여 치아를 삭제하는 과정이다. 치아에 비하여 시술도구의 크기가 상대적으로 매우 작기 때문에 보다 정교한 충돌감지뿐만 아니라 치아 삭제에 따른 형태변형에 동기화된 정확한 충돌 모델이 요구된다. 따라서 본 논문에서는 디스턴스 필드를 이용한 볼륨 모델을 치아에 적용하고 이를 형태변형 시각화와 햅틱 렌더링에 함께 이용하는 실시간 충돌 모델을 제안한다. 또한 안정적인 햅틱 피드백을 위해 버의 포인트 쉘 생성 방법과 시간 응집도에 따른 점 접촉 모델 가속화 방법을 제시한다.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.5
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• pp.116-123
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• 2000

This paper presents an NC code post-processor that adjusts feedrates to keep the variation of metal removal rate along the tool paths minimum. Metal removal rate is estimated by virtually machining the part, whose surface model is built from a series of NC codes defined in operation plan, with cutting-tool-assembly models, whose geometry are defined in a machining database. The NC code post-processor modifies the feedrates by the adjustment rules, which are based on the machining knowledge for effective machining. This paper illustrates a procedure fur grouping machining conditions and we also show how to determine an adjustment rule for a machining-condition group. An example part was machined and it shows that the variation of cutting force was dramatically reduced after applying the NC code post-processor. The NC code post-processor is expected to increase productivity while maintaining the quality of the machined part.