• Proceedings of the Safety Management and Science Conference
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• 2006.11a
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• pp.239-254
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• 2006

In mold structure machining, tool interference is a phenomenon which results from a collision between a blade of tool and a workpiece. Also tool collision is a phenomenon which results from a collision of holder with the object to be machined. These phenomena not only cause damages to mold and tool but also increase machining time and cost. To detect a collision of a tool to mold structure, first of all, the mold structure and a tool must be defined with famous geometric models such CSG, B-rep, and Voxel. A tool is defined as a combination of the blade, the shank, and the holder. This thesis reviews various collision detection algorithms using z-map and computer 3D graphic collision detection algorithms for the tool in machining a mold structure.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.116-121
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• 2001

Verification of tool collision is an important issue in die and mold machining. In this paper three functions of verification are schematically explained based on Z-Map model. The first function is getting a collision-free region when a tool assembly and a part surface model are given. The second function estimates the shortest length of cutter shank with that the tool cuts all of a region without collision. The last one is cutting simulation considering all parts of tool assembly as well as cutter blade. Those functions can be easily implemented by using several basic operators of Z-Map model which are explained also. Proposed approaches have enough accuracy to verify collision in reasonable computing time.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.6
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• pp.35-42
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• 2002

Verification of tool collision Is an important issue in die and mold machining. In this paper three functions of verification for 3-axis milling machining are schematically explained. Operators of geometric models are explained at first, which will be used in the functions of verification. The first verification function is getting a collision-free region when a tool assembly and a part surface model are given. The second function estimates the shortest length of cutter shank with that the tool cuts all of a region without collision The last one is cutting simulation considering all parts of tool assembly as well as cutter blade. Proposed approaches can be easily implemented by using several basic operators of geometric model. An example to calculate collision-free region is presented also.

• Journal of Computational Design and Engineering
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• v.2 no.4
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• pp.197-205
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• 2015

Bladed disk (BLISK) is a vital part in jet engines with a complicated shape which is exclusively machined on a five-axis machine and requires high accuracy of machining. Poor quality of tool orientation (e.g., false tool positioning and unsmooth tool orientation transition) during the five-axis machining may cause collision and machine vibration, which will debase the machining quality and in the worst case sabotage the BLISK. This paper presents a reference plane based algorithm to generate a set of smoothly aligned tool orientations along a tool path. The proposed method guarantees that no collision would occur anywhere along the tool path, and the overall smoothness is globally optimized. A preliminary simulation verification of the proposed algorithm is conducted on a BLISK model and the tool orientation generated is found to be stable, smooth, and well-formed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.367-372
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• 2003

This paper shows about the machine simulation embodiment when it happened NC equipment and between workpiece and interference collision at 5 axises processing of aircraft parts. And this research has been chosen because of the highest equipment interference occurrence rate at aircraft parts processing of 5 axises horizontal machine. It can verify simulation and machining process through correlation about their dynamic relations. interference, collision as embodied virtual manufacturing system of machining tool, workpiece, and holder etc. that is necessary element in shape of machine tool and function and processing in imagination ball. Also. it verified about interference and collision between NC equipment parts and workpiece, for applied machine simulation to NC Data of actuality aircraft parts of BULKHEAD and FRAME.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.323-326
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• 2006

The operation planning of multi-AUV is considered as a very difficult task. This paper proposes the qualitative method about the operation plan of multi-agents. In order to achieve this goal, it applies an extension collision map method as a tool to avoide collision between multi AUVs. This tool has been developed for the purpose of collision forecasting and collision avoidance for the multi - agents system in a land where a control is much easier. This paper analyzes the avoidance value of maximum path of AUV in order to apply this to a water environment where a tidal, a wave and disturbances are common. And it suggests the method that the maximum path avoidance can be applied to the collision avoidance on the extension collision map. Finally, the result proves that multi AUVs effectively navigates to the goal point, avoiding the collision by the suggested method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.1050-1053
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• 1995

A stock removal cycle is developed as a programming tool of the CNC lathe. This cycle support the easiness and swifness of a part program generation in the shopfloor. The cycle contains the function of tool path generation of rough/finish cutting, of avoidance air-cut for non-cylindrical (die-casted, forged) workpiece, and of the tool collisopn detection/aviodance. Consequently the intelligent stock removal cycle results in improving the productivity and safety of CNC lathe.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.199-204
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• 1994

A method for determining the collision-free tool orientation for 5-axis milling is presented. In 5-axis milling, the proper tool orientation as well as the optimal CC-data has to be selected to machine the workpiece efficiently and accurately and accurately. Essentially, the tool orientation should be determined to avoid collisions between the tool and workpiece and to enable efficient machining. In this work, the tool orientation is determined at every CC-point which is assumed to be given. The procedure uses the potential energy method that assumes the tool and the part surfaces are charged with static electricity. This approach can detect can deteat both global and local collisions (gouging) irrespective of the tool shape. Further, in order to increase the machining efficiency, the material removal rate is maximized simultaneously.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.2
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• pp.156-163
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• 2013

Collision probability is the most common method to measure the risk of space debris, it is widely used that two dimensional linear collision probability using the closest approach distance. This paper represents the characteristics of object that approach KOMPSAT 2, 3, 5 that have operated or will be operated by Korea. And more precise method than two dimensional linear collision probability, we analyzed the properties of three dimensional nonlinear collision probability using STK/Nonlinear Collision Probability Tool. Through this, efficiency of three dimensional nonlinear collision probability for KOMPSAT series satellites was investigated. The result represents that three dimensional nonlinear collision probability showed the precise outcome at a relative velocity of less than 350m/s. Also, KOMPSAT series satellites appeared to few low relative velocity approaches and showed low efficiency for the three dimensional nonlinear collision probability.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.161-167
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• 1996

In five-axis milling, optimal CL-data (cutter location data) should be generated to have advantages over three-axis milling in terms of accuracy and efficiency. This paper presents an algorithm for generating collision-free CL-data for five-axis milling using potential energy method. By virtually charging the cutter and part surfaces with static electricity, global collision as wells as local interference is eliminated. Additionally, machining efficiency is improved by minimizing the curvature difference between the part surface and tool swept surface at a CC-point (cutter contact point) simultaneously.