• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.178-189
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• 1993

Engineering ceramics have some excellent properties as the material for the mechanical components. It is, however, very difficult to grind ceramics with high efficiency because of their high strength, hardness and brittleness. In this paper experiments are carried out to obtain the effect of "In-process dressing" to grind the Engineering ceramics with high efficiency. To save running time for dressing process and obtain restraint effect of diamond grain wear, "In-process dressing" system usint WA stick type honing stone is proposed. Representative High Strength Engineering ceramics A1$_{2}$O$_{3}$ and Si$_{3}$N$_{4}$are ground with diamond wheel. Also bending strengrh test is carried out to check upward tendancy of mecahnical properties as the result of machining defact restraint through the grinding maching method using "In-process dressing" process. Some results obtained in this study provide useful information to attain the high efficency grinding and the high mechanical properties of Engineering ceramics.rties of Engineering ceramics.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.117-122
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• 2002

The chatter to raise grinding operating is reduce the precision and the quality. In this study, In reply to AE signal and the normal force generated in the grinding operating were measured (1) the amplitude in the mathematical model of the normal force is the form as to transform an exponential (2) the chatter growth is minus point of an exponent. (3) From the observed wheel aspect after the chatter growth, it was to investigated the concern of the chatter growth and the wheel life.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.1
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• pp.69-74
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• 2014

An OrthoMTA compacter is made by machining a Ni-Ti alloy wire using tapered helix creep-feed grinding machines. This aim of this study is to find the optimal dressing conditions to sharpen the corner of a cubic boron nitride (CBN) wheel. On the basis of the results of various experiments, it is verified that the most important factors in dressing are the dressing depth and feeding method, whereas the feed rate has less importance for producing a smaller corner R value. The study also finds the optimum dressing depth to reduce the dressing time, a feeding speed and method to stabilize the machining, and the mesh grade for the CBN wheel to make the groove of the compacter deeper.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.12
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• pp.56-65
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• 1997

This paper presents the robot program for propeller grinding. A robot manipulator is constructed by combining a parallel and a serial mechanism to increase high sitffness as well as workspace. The robot program involves inverse/direct kinematics, velocity mapping, Jacobian, and etc. They are cerived in efficient formulations and implemented in a real time control. A velocity control is used to measure the hight of a propeller blade with a touch probe and a position control is performed to grind the surface of the blade.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.79-83
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• 2001

Posture of the upper limbs in field works is known to be an important risk factor associated with CTD(Cumulative Trauma Disorders). In particular, uncomfortable posture and highly repetitive works in shipbuilding industry(for instance, sand blasting, grinding and blast painting, etc) made workers exposed to a great risk of injuries. The purpose of this paper is to analyze recruitment pattern of the muscles according to posture(joint angle displacement) during grinding. In this study, EMG signals of pectoralis major, latissimus dorsi, and posterior deltoid muscle were measured and analyzed from FlexComp EMG solution. And subjective ratings of perceived exertion were made using Borg's CR-10 rating scale.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.1
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• pp.81-87
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• 2000

A variable cutting speed control model was developed to be implemented for the flexible disk grinding process Control algorithm was based on the error referred by the discrepancy between current disk angle and intended one that are pro-posed to produce desired resulting depth of cut. Controller was implemented in two different aspect One was to initiate the control law from the beginning while the other was to activate as soon as the disk start to produce ground surface i.e. The beginning of the between edges stage. Several performance analysis were conducted comparing various process parameters such as cutting force disk angle depth of cut and disk speed with respect to process transition time Tentative results revealed that controller implemented from the earlier stages of the process showed better performance than the other revealed that controller implemented from the earlier stages of the process showed better performance that the other.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.53-57
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• 2002

The chatter to raise grinding operating is reduce the precision and the quality. In this study, In reply to AE signal and the normal force generated in the grinding operating were measured (1) the amplitude in the mathematical model of the normal force is the form as to transform an exponential (2) the chatter growth is minus point of an exponent. (3) From the observed wheel aspect after the chatter growth, it was to investigated the concern of the chatter growth and the wheel life.

• International Journal of Control, Automation, and Systems
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• v.6 no.3
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• pp.386-393
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• 2008

A position control method for interpolating aspherical grinding and polishing tool path was reviewed and experimented in a nano precision machine. The position-base algorithm was reformed from the time-base algorithm, proposed in the previous study. The characteristics of the algorithm were in the velocity control loop with position feedback. The aspherical surface was divided by an interval at which each velocity and acceleration were calculated. The theoretical velocity was corrected by position error during processing. In the experiment, a machine was constructed and nano-scale linear encoders were installed at each axis. Relation between process parameters and the variation of position error was monitored and discussed. The best result from optimized parameters showed that the accuracy was 150nm and improved from the previous report.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.326-331
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• 1999

Grinding technology in morden industry society is focusing on research & development for grinding stone and machining parts for the purpose of high accuracy and high efficiency of products. But, in order to equip the high technology and high accuracy of micro stone which is one of grinding stone, hardly and continuous effort on R&D is required.In this study, honing processing work of 2-cycle engine cylinder for motorcycle which has open hole is practiced so as to clear how borning that is prior step of honing and hone stone make an influence on accuracy of honing. As the result of analyzing the results of experiments, we came to conclusion that we can secure good conditions of honing by controlling and keeping appropriate cycle-time in the stage of boring of prior step of honing.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.270-276
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• 2000

Hard turning has the potential to replace grinding process and to achieve significant reduction in production time and cost. The main applications for hard turning is finishing process, namely grinding process. Therefore, it must be able to satisfy high surface integrity of the workpiece. This paper discusses surface quality in terms of residual stress and damaged layer with respect to cutting parameters in an intermittent hard turning. Damaged layer experiment is carried out orthogonal array. From that is based on the orthogonal array. From the response table, cutting parameters are analyzed from the view point of the damaged layer and residual stress. From this experimental results, even though in the intermittent hard turning, surface integrity turns out be good enough for replacing grinding process.