• 한국기계가공학회지
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• 제6권2호
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• pp.41-46
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• 2007

Butterfly valves are commonly used as control valves in applications where the pressure drops required of the valves relatively low. As the shutoff valve (on/off service) or throttling valves (for flow or pressure control), the higher order and the better precision of butterfly valves are required. The it's more and more essential to know the flow characteristic around the valve. Due to the fast progress of the flow visualization and numerical technique, it becomes possible to observe the flows around a valve and to estimate the performance of a valve. Researching these results did not gave only access to understand the process of the valve flows at different valve opening angles, but also was made to determine the accuracy of the employed method. Furthermore, the results of the three-dimensional analysis can be used in the design of butterfly valve in the industry.

• 한국생산제조학회지
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• 제8권5호
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• pp.70-75
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• 1999

Adaptive control in the robotic GMA(Gas Metal Arc) welding is employed to monitor the information about weld characteristics and process paramters as well as modification of those parameters to hold weld quality within the acceptable limits. Typical characteristics are the bead geometry composition micrrostructure appearance and process parameters which govern the quality of the final weld. The main objectives of this paper are to realize the mapping characteristicso f penetration through the learning. After learning the neural network can predict the pene-traition desired from the learning mapping characteristic. The design parameters of the neural network estimator(the number of hidden layers and the number of nodes in a layer) were chosen from an error analysis. partial-penetration single-pass bead-on-plate welds were fabricated in 12mm mild steel plates in order to verify the performance of the neural network estimator. The experimental results show that the proposed neural network estimator can predict the penetration with reasonable accuracy and gurarantee the uniform weld quality.

• 한국생산제조학회지
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• 제7권2호
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• pp.40-46
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• 1998

In order to achieve high flexibility in manufacture, chip control is one of the most serious problems at present. The continuous type chip (uncontrolled chip), which interrupts the normal cutting process and damages the operator, tool and workpiece have a higher force ratio. while the controlled chip which is 6 or 9 type and C type, has the values of the force ratio below 0.6 The chips were classified by 4 types. in chip formation and by described chip history during the cutting process. Finally, the feasibility of utilizing force ratios in chip control will be pointed out while comparing generated force signals during the cutting process.

• 한국기계가공학회지
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• 제21권6호
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• pp.22-29
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• 2022

In this study, an automatic marking system for fabric inspection machines was developed. The main objectives of the study were to promote intelligence and automation for the inspection process, as well as to increase textile industrial productivity. Generally, when a worker manually inspects and marks a fabric, human error and reduced efficiency are unavoidable. To overcome these problems, we developed an automatic marking system that uses robots. This system incorporates a vision camera to automatically recognize defects, and an optical fiber sensor to detect the side of the fabric. To verify the performance, the control system sends a command directly to the robot to mark the fabric. Finally, the actual production confirmed that the proposed system could perform the desired motion.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.704-706
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• 1991

In CAD/CAM system, many efforts are made to automate the converting process from drawling information to manufacturing Information. The most difficult step In this procedure is utilizing 2 dimensional drawing information In order to formulate 3 dimensional w&ling information. This paper emphasizes to mWe automatically series of convertirg steps which provide 3 dimensional wire frame, surface and solid modeling using feature recognition rules. With the standardization of design process and the recognition rule as preceding steps, it shows a good application tool to interface the design and manufacturing procedures in PC-Level CAD/CAM system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.358-363
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• 1992

The tire manufacturing process demands classification of tire types when the tires are transferred between the inner processes. Though most processes are being well automated, the classification relies greatly upon the visual inspection of humen. This has been an obstacle to the factory automation of tire manufacturing companies. This paper proposes an effective vision systems which can be usefully applied to the tire classification process in real time. The system adopts a parallel architecture using multiple transputers and contains the algorithms of preprocesssing for character recognition. The system can be easily expandable to manipulate the large data that can be processed seperately.

• 대한조선학회논문집
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• 제43권3호
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• pp.392-398
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• 2006

A prototype of MES(Manufacturing Execution System) applied to panel assembly shop is implemented by using PDA(Personal Digital Assistant) and wireless database web server. The system is developed based on the Dot Net framework. The prototype can exchange the manufacturing execution data between production managers in the control room and workers in the factory through wireless internet communication. Manufacturing model of the panel shop is designed by using IDEF0 and UML method to understand the characteristics of the information and the data entities from the PPR-S view. Several issues in the shop were revealed from the manufacturing model analysis. The most typical problem was the lack of information sharing between the managing workers and the assembly workers. The problem prevents the workers and labors from sharing the process information and continuous workpiece flow In interactive way. To increase the information and data flow, a wireless internet based system is implemented and PDAs are linked together to exchange the process planning data and in-process data between the workers. It is anticipated that PDA and the implemented system can enable the process control at each process stages to obtain the well-organized operation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.365-368
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• 1992

This paper presents an approach to the design of real time task scheduling for a line controller of continuous manufacturing process automation. The line controller has multiprocessor-based architecture with shared memory and is operated by firmware. This firmware contains menu-driven software supporting real-time database management and fuction-block control language. The multitasking line control processor performs the following three functions: 1) interprets the function block control language by virtue of shared memory in the database; 2) invokes an interupt service routine as required by external hardware; 3) detects errors and notifies the user. We propose real time task scheduling method.

• 한국기계가공학회지
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• 제19권8호
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• pp.81-87
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• 2020

A stable rotational-to-linear motion transformation structure using a driving mechanism with 2 degrees of freedom was developed for an orthogonal mechanism to prevent the interference of each axis in 2D motion. In this mechanism, a step motor was used for precise position control. This structure was developed to maneuver workparts in micro particle blast machining experiments. To determine the real-time performance of micro particle blast machining, the control, input, and output were operated simultaneously and precise position control was implemented, using a timer interrupt with multiple execution codes. The two step motors obtained precise position control by removing backlash with a ball-screw mechanism. The device has menu-type control codes for user-friendliness, and real-time sequence control was simultaneously adopted for user control input.

• 한국기계가공학회지
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• 제18권4호
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• pp.10-15
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• 2019

In this paper, we report a robust steering control using time delay control for the vehicle dynamics variation due to tire/road contact condition variation, the lateral disturbance force due to the side wind, and the yaw disturbance moment due to the difference between the left and right tires' pneumatic pressure. We controlled the side slip and yaw damping compensation for rapid steering at the high velocity of the vehicle. Based on the developed control, the driver can only consider the desired path without concerning on the vehicle dynamics variation, disturbances, and undesired side slip and yaw oscillations. Simulation results show that robustness from the vehicle dynamics variation and disturbances was achieved by using the developed time delay control. We evaluated the side slip and yaw damping compensation capability for the rapid steering at the high velocity of the vehicle in the cases of three control methods.