• Journal of Institute of Control, Robotics and Systems
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• v.6 no.8
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• pp.697-702
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• 2000

The paper considers the problem of improving the productivity of surface mounting in the printed circuit board(PCB) assembly line. This problem is generally divided into two problems ; real assignment problem and pick-and -place sequencing problem which are known to have no polynomial time algorithms. In the last ten years algorithm designers have been trying to solve them separately. However they need to be solved jointly because they are highly interrelated. This paper proposes an evolutionary algorithm which can consider the two problems jointly and thus yield a better solution. In order to evaluate the proposed algorithm computer simulation is performed on real-life surface mounting machines. The proposed algorithm is expected to reduce the assembly time of surface mounting machines and thus improve the productivity.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1117-1122
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• 1993

The environment for surface mounting machines plays an important role in a throughput. An approach to organize the optimal integrated environment for surface mounting machines is presented to increase a throughput. An optimization problem is divided into a feeder setting problem and a task sequencing problem. Two algorithms for each problem are proposed. The feeder setting problems is optimized by an algorithm based on heuristic methods. The task sequencing problem is modeled as a TSP(Traveling salesman problem). An algorithm based on a heuristic tour-to-tour improvement method for TSP is proposed to optimize the task sequencing problem. A simulation is carried out to test developed algorithms.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.586-589
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• 2001

In Case of High speed PM machines with surface-mounted magnet. A rare-earth PM with high remanence flux density is used on the rotor. Therefore, It is very difficult to adhesion and assemble PM on the surface of rotor, because of very repulsive force between magnets. So, for solving this problem, rotor with surface-mounted magnet is wholly magnetized after mounting magnetic-material on the surface. In this paper, In order to Magnetize rotor with surface-mounted PM, magnetizing machine is designed, analyzed and simulated for large PM machines using the 1dimensional analytical method and 2dimensional finite element method. (20-FEM).

• Journal of the Korean Society for Precision Engineering
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• v.12 no.8
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• pp.106-113
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• 1995

Surface mounters are used to mount the parts of electronic products on PCB(Printed Circuit Board. Those machines rely on high precision, high productivity, and software for accomodation of use. In this paper, two algorithms and a software which can give the users the acco-modation and high productivity for rotary type surface mounters are presented. The algo- rithms for development of of the software consider all factors which affect the effeciency of the operation. And the interface between user and machine for the accomodation of use can be achieved through the developed software.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.1
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• pp.37-42
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• 1990

Carbon fiber epoxy composite materials are widely used in the structures of aircrafts, robots and other machines because of their high specific stiffness, high specific strength and damping. In order for the composite materials to be used in the robot structure or machine element, bearing mounting and joining surfaces must be provided, which require accurate machining. In this paper, the machinability and tool wear characteristics of the milling operation of the carbon fiber epoxy composite materials were experimentally measured. The tool wear mechanism and the Taylor tool wear constants were determined. Also, the surface roughness of milling operation was measured w.r.t. cutting speed and feed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.4
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• pp.117-122
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• 1998

Glass fiber epoxy composite material is widely used in the structures of aircrafts, robots and other machines because of their high specific strength, high specific stiffness and high damping. In order for the composite materials to be used in the aircraft structures or machine elements, accurate surfaces for bearing mounting or joint must be provided, which require precise machining. In this paper, the machinability of the glass fiber epoxy composite material was experimentally investigated. The results can be summarized as follows : 1. The entrance of hole is very good manufacturing existing, but exit come to occur sever surface exfoliation. 2. The cutting force in drilling of the glass fiber epoxy composite material is decreased as the drilling speed increased. 3. If the glass fiber epoxy composite material is drilling by the standard twist drill, then the hole recommand cutting condition is spindle speed 400∼600rpm, feed 40∼50mm/min.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.10
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• pp.203-208
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• 1998

Carbon fiber epoxy composite materials are widely used in the structures of aircrafts, robots and other machines because of their high specific strength, high specific stiffness and high damping. In order for the composite materials to be used in the aircraft structures or machine elements, accurate surfaces for bearing mounting or joints must be provided, which require precise machining. In this paper, the machinability characterisitcs of the drilling operation of the carbon fiber epoxy composite materials was experimentally investigated. The experimental results are as follows 1.The entrance of hole is very good manufacturing existing, but exit come to occur sever surface exfoliation. 2. The cutting force in drilling of the carbon fiber epoxy composite materials is decreased as the drilling speed increased. 3.The hole of the carbon fiber epoxy composite materials is not good manufacturing by use of the standard twist, therefore, the new drill designed in order to accurate hole.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.1
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• pp.63-71
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• 2006

In this paper, we consider a planning problem arising from printed circuit board manufacturing industries. Given a set of several types of PCBs, component feeders and surface mounting machines in series in a PCB assembly line, the problem is to define the feeder allocation and job sequence with the objective of minimizing the total operation time of the line. We formulate the problem as a mathematical model. And, the problem is proven to be NP-hard, so a genetic algorithm is developed. Finally, we give test results to evaluate the performance of the genetic algorithm.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.1
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• pp.63-73
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• 1991

Carbon fiber epoxy composite materials are widely used in the structures of aircrafts, robots and other machines because of their high specific strength, high specific stiffness and high damping. In order for the composite materials to be used in aircraft structures or machine elements, accurate surfaces for bearing mounting or joints must be provided, which require precise machining. In this paper, the machinability of the carbon fiber epoxy composite materials in turning was experimentally investigated. The cutting mechanism and the Taylor Tool Wear constants were determined and the surface roughness was measured w.r.t. cutting speeds and feed rates.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.3
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• pp.276-282
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• 2015

This paper proposes a SMD (surface mounting device) classification method for the PCB assembly inspection machines. The package types of SMD components should be classified to create the job program of the inspection machine. In order to reduce the creation time of job program, we developed the automatic classification algorithm for the SMD packages. We identified the chip-type packages by color and edge distribution of the images. The input images are transformed into the HSI color model, and the binarized histroms are extracted for H and S spaces. Also the edges are extracted from the binarized image, and quantized histograms are obtained for horizontal and vertical direction. The neural network is then applied to classify the package types from the histogram inputs. The experimental results are presented to verify the usefulness of the proposed method.