• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.2
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• pp.137-143
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• 1999

The study of the high speed machining of inclined plane using ball end mill is performed. The use of ball end mill is rapidly growing in die and mold manufacturing. The cutting characteristics, such as cuttin g force, surface roughness and surface profile, are varied according to the variation of cutting directions. Free surface is cut using ball end mill, the surface profile is greatly varied depending upon the cutting direction. So this study will deal with the characteristics of cutting such as cutting efficiency according to the inclined plane of the workpiece, the cutting force according to tool path, surface profile and the roughness of surface. The optimal cutting direction to be applied the cutting for 3-D sculptured surfaces can be show through the results of this study.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.109-118
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• 1999

The objective of this research is to develop an effective inspection planning strategy for sculpture surfaces in OMM(On-Machine Measurement) process. As a first step, effective measuring point locations are determined to obtain optimum results for given sampling numbers. Two measuring point selection methods are suggested in this study based on newly proposed CAD/CAM/CAI integration concept: (1) by the prediction of cutting errors, (2) by considering cutter contact points to avoid the measurement errors caused by cusps. As a next step, the TSP(Traveling Salesman Problem)algorithm is applied to minimize the probe moving distance. Appropriate simulations and experiments are performed to verify the proposed inspection planning strategy in this study, and the results are analyzed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.426-429
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• 2001

Many various products are manufactured which have sculptured surfaces recently. Constructing surface of these models is required technique called reverse engineering. In reverse engineering, a product which has sculptured surfaces is measured and we create surface model to acquire complete model data of object. Measured point data needs preprocess and sampling. Next a set of point data in a plane fit section curve. At last, surface is generated by fitting to section curves. Here we uses sweep surface. Sweep surface is compatible fitting CAD model to drawing. This paper discusses converting approximation of NURBS surface as a standard surface.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.84-94
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• 1991

In order to achieve high accuracy of teaching and increase productivity using industrial robots in polishing process of dies, an off-line task programming system was developed on IBM-PC/386 under WINDOWS 3.0 operating system. The internal structure and the machematical basis of CAMPoli are described. Surface modeling technique of polishing dies with sculptured surfaces is introduced by poing data interpolation methodology through the use of CL-data transmitted from conventional CAM system. Tool selection, polishing speed, polishing pressure and kinds of tool motions can be determined and selected by user specified polishing variables. Task creation and verification of polishing path via computer graphics simulation of polishing tool can be done by the menu- driven function of CAMPoli system. Post-processing module is attached to generate robot language. Some simulation results are provided as verification means of the system.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.114-121
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• 1997

In this paper, the automated initial process planning for 3-axis NC machining of sculptured surfaces is persented. The solution algorithms determining three process planning functions, i.e. machining feasibility, setup orientation and feasible machine selection are developed. The machining feasibility is determined by means of BSM(Binary Spherical Map) which derives its solution quickly in algebraic form, and the setup orientation is determined so that the cutting force is minimized. Finally, the feasible machine is determined by computing the minimum motion ranges of each control axisl. The developed algorithms are tested by numerical simulations, convincing they can by readily implemented on the CAD/CAM system as a process planner.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.1
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• pp.52-61
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• 1993

Developed in this research is a CAM system for 5-axis NC Machining of sculptured surfaces. We identify problems in generating 5-axis NC data and propose methods of overcoming them. Issues discussed in this paper are: kinematic modelling of NC machines; determination of cutter position (location and orientation); check of machine work-range; linear trajectory plann- ing ; calculation of feedrate number. The proposed system has been implemented in FORTRAN77 on the Personal IRIS EWS, and it also constitutes a module of the CAD/CAM system 'CASSET' developed in KIST CAD/CAM lab.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.12
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• pp.100-106
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• 2021

This paper presents a study on the improvement of the machining quality of sculptured-surfaces of molds according to the shape and posture of the tool. In the existing 3-axis machining, the methods using the ball end-mill and radius end-mill were analyzed for various cutting patterns and compared with those of the 5-axis machining. It was observed that the 5-axis machining using a ball end-mill obtained the finest surface roughness, and for the 3-axis machining, the optimal results were obtained for the one-way machining using a radius end-mill.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.10
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• pp.121-129
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• 1995

The objective of this research is to develop an effective inspection planning strategy for sculptured surfaces by using 3-dimensional Coordinate Measuring Machine (CMM). First, the CAD/CAM database is generated by using the Bezier surface patch mathod and variable cutter step size approach for design and machining of the workpiece model. Then, optimum measuring point locations are determained based on the mean curvature analysis to obtain more effective inspection results for the given sample numbers. An optimal probe sequence generation method is proposed by implementing the Traveling Salesperson (TSP) algorithm and new guide point selection methods are suggested based on the concepts of the variable distance between the first and second guide points. Finally, simulation study and experimental work show the effectiveness of the proposed strategy.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.6
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• pp.1372-1380
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• 1993

Surface trimming is an essential function in a surface modeler for representing multi-boundary surfaces, blended surfaces, and surfaces with islands or pockets. A procedure and a data structure for designing trimmed surfaces were developed. For generating a trimmed surface, edges (curves difined on a surface) are generated and trimmed first. Then the trimmed edges are selected sequentially to form a closed loop. The data of supporting surface, surface on which the trimmed surface is defined, and bounding edges are stored and used for the application such as NC programming, robot programming, graphic display, etc.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.48-51
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• 2004

The estimation of NC machining time is of significance since it provides shop floor engineers with information for the determination of the productivity of the floor as well as process schedules. The NC machining time commonly depends on NC programs since they have various important information such as tool positions, feed rates, and other miscellaneous functions. Thus, nominal NC machining time can be easily acquired based on the programs. Actual machining time, however, cannot be simply obtained because of the dynamic characteristics of a NC machine controller such as acceleration and deceleration. Hence, this study presents a NC machine time estimation model for sculptured surfaces, considering the dynamic characteristics. The estimation model uses the distribution of NC blocks according to a factor influencing the machining time. Finally, machining time is estimated by a statistical machining time estimation model representing the relationship between the block distribution and the machining time. The parameters in the model are searched out by a genetic algorithm.