• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1997.12a
• /
• pp.392-400
• /
• 1997

This study was conducted to develope the machine vision system of a robotic transplanter for bedding plants. Specific objectives of this study were 1) to get coordinates of the healthy seedlings except empty cells and bad seedlings in high-density plug tray, and 2) to get the angle of the leaves of the healthy seedlings to avoid damage to the seedlings by gripper. The results of this study are summarized as follows. (1) The machine vision system of a robotic transplanter was developed. (2) The success rates of detecting empty cell and bad seedlings in 72-cell and 128-cell plug trays were 98.8% and 94.9% respectively. (3) The success rates of calculating the angle of leaves in 72-cell and 128-cell plug trays were 93.5% and 91.0% respectively.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.5
• /
• pp.34-42
• /
• 1998

This paper describes an analysis of measuring error of on the machine measuring(OMM) system which directly measures machined surface dimensions using scanning probe on a CNC milling machine. 21 inch TV shadow mask mould clamped to a pallet was measured using PTP(point to point) measuring algorithm in OMM system and the results were compared with those using coordinate measuring machine(CMM). The OMM error was evaluated by probe error, stylus contact error, center shift error, repeatability, work-piece clamping error and etc. The results show that elastic deformation of the pallet is most affecting factor on the measuring error, thus pallet design and clamping method need very careful cosiderations.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2003.10a
• /
• pp.396-400
• /
• 2003

This paper has studied thermal characteristics of machine tool to develope high speed spindle and optimum design condidering the thermal deformation. Comparing the test data of temperature measurement and structural analysis data using FEM, we verifiedthe test validity and predicted thermal deformation, influence of spindle generation of heat, and established cooling system to prevent the thermal deformation. 1) The temperature rise of spindle system depends on increasing number of rotation and shows sudden doubling increment of number of rotation over 7,000rpm. 2) Oil jacket cooling can be effective cooling method below 8,000rpm but, over 8,000rpm, it shows the decrement of cooling effect. 3) Comparing FEM analysis results and revolution test results, we can confirmn approximate temperature change consequently, it is possible to simulate temperature rise and thermal distribution on the inside of spindle system. 4) We can confirm that simulated approach by FEM analysis can be effective method in thermal-appropriate design..

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.1908-1912
• /
• 2007

The metropolitan area needs to control the Automatic Fare Collection (AFC) and transportation card system in order to implement an efficient railway and subway. This paper introduces a suitable analysis to take advantage of the systematic method of the AFC and transportation card. These systems should consider the fare system, transportation pass and AFC equipment, which are organized with the Automatic Ticket Vending Machine, the Ticket Office Machine and the Card System of Radio Frequency (RF). However, the organization includes the fact the Automatic Ticket Vending Machine has a problem with the proceeding speed of passengers and inconvenience. Second, the majority of passengers have not utilized the Ticket Office Machine. Also, it should consider whether the transportation card is the proper system in the metropolitan area. Based on the analysis of national and international cases, it suggests that the AFC should make more improvements in the metropolitan area railway and subway.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.48 no.6
• /
• pp.301-308
• /
• 1999

According to the development of power electronic element(GTO, IGBT) and material for electrical machines(permanent magnet, super conductor), the technology for electrical machines is now a day rapidly developing. Here with, a novel electrical machine, based on the new conception of transverse flux configuration leads to a considerable increase in power density and enables simultaneously high efficiency. The designed and measured performance of transverse machine for railway traction system revealed a great potential of system improvements to reduce linear motor mass.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.17 no.2
• /
• pp.145-162
• /
• 1992

This paper proposes two design principles for expert systems to solve a stock market timing (SMART) problems : machine knowledge and fuzzy post-adjustment, Machine knowledge is derived from past SMART instances by using an inductive learning algorithm. A knowledge-based solution, which can be regarded as a prior SMART strategy, is then obtained on the basis of the machine knowledge. Fuzzy post-adjustment (FPA) refers to a Bayesian-like reasoning, allowing the prior SMART strategy to be revised by the fuzzy evaluation of environmental factors that might effect the SMART strategy. A prototype system, named K-SISS2 (Knowledge-based Stock Investment Support System 2), was implemented using the two design principles and tested for solving the SMART problem that is aimed at choosing the best time to buy or sell stocks. The prototype system worked very well in an actual stock investment situation, illustrating basic ideas and techniques underlying the suggested design principles.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.11a
• /
• pp.621-625
• /
• 1996

The feed system of the machine tools is limited by the mechanical transmission elements. However, thanks to the advanced modern technology, those machines are able to equip with linear motors. In this paper, the types and application aspects of linear motor are discussed and a synchronous type of the linear motors has been applied to X-Y table for machining center. The performance shows an outstanding result in terms of the accuracy, speed and stiffness. Machine tool system with linear motors is expected to be more productive machines using linear motor in the near next years.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.7-10
• /
• 2002

The diagnosis of faults of machine tool, which is controlled by CNC and PLC, is generally based on ladder diagram of PLC. Because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching for logical relation to fault reasons is required a lot of fault experiences and times, because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault lastly and correctly. The diagnosed reasons for fault are tele-serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• Korean Journal of Computational Design and Engineering
• /
• v.2 no.2
• /
• pp.111-121
• /
• 1997

This study intends to develop a fixture planning module as a part of the planning system for cutting. The fixture module uses machine learning method to reuse previous failure results so that the system can reduce the repeated failures. Machine learning is one of efforts to incorporate human reasoning ability into a computerized system. A human expert designs better than a novice does because he has a wide experience in a specific area. This study implements the machine learning algorithm to have a wide experience in the fixture planning area as a human expert does. When the fixture planner finds a setup failure for the suggested operations by a process planner, it makes the process planner store its attributes and other information for the failed setup. Then the process planner applies the learned knowledge when it meets a similar case so that the planner can reduce possibility of setup failure. Also the system can teach a novice user by showing a failed setup with a modified setup.

• Proceedings of the KIPE Conference
• /
• 2005.07a
• /
• pp.479-482
• /
• 2005

본 연구는 알루미늄 단조 라인의 가열로 컨베이어에 적용된 6관절 이송용 로봇에 Machine Vision System을 구축 한 것으로 이송용 로봇이 작업 대상물을 적재하기 위한 위치정보를 획득하고 재처리하여 로봇 컨트롤러에 제공하는 비주얼가이던스 기법을 연구하여 이를 적용하였다. 적용된 Machine Vision System이 실제 구동에 있어서 안정함을 확인하였다. Machine Vision System에 적용된 CCD 센서로는 Sony사의 XC-HR50이 적용되었으며 Frame Grabber는 Matrox Meter II 카드가 적용되었다. Machine Vision System 제어기로는 범용PC(2.4Ghz, Windows 2000)를 사용하였으며 제어Software는 Microsoft 사의 Visual Basic 6.0 version을 사용하였다.