• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.48-51
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• 1996

A 5-bar structure with redundant actuators is proposed as a finger mechanism. It is shown that one additional redundant actuator greatly enhances the load handling capacity of the system. The actuator location should be carefully decided to maximize the performance enhancement. Furthermore, we develop stiffness and frequency control algorithms based on the internal loading created by redundant actuation. The effectiveness of these algorithms have been demonstrated by simulations.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.2
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• pp.406-423
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• 2014

The recent advances in wireless communication systems and semiconductor technologies are paving the way for new applications over wireless sensor networks. Health-monitoring application (HMA) is one such emerging technology that is focused on sensing and reporting human vital signs through the communication network comprising sensor devices in the vicinity of the human body. The sensed vital signs can be divided into two categories based on the importance and the frequency of occurrence: occasional emergency signs and regular normal signs. The occasional emergency signs are critical, so they have to be delivered by the specified deadlines, whereas the regular normal signs are non-critical and are only required to be delivered with best effort. Handling the occasional emergency sign is one of the most important attributes in HMA because a human life may depend on correct handling of the situation. That is why the underlying network protocol suite for HMA should ensure that the emergency signs will be reported in a timely manner. However, HMA based on IEEE 802.15.4 might not be able to do so owing to the lack of an appropriate emergency-handling mechanism. Hence, in this paper, we propose a new emergency-handling mechanism to reduce the emergency reporting delay in IEEE 802.15.4 through the modified superframe structure. A fraction of an inactive period is modified into three new periods called the emergency reporting period, emergency beacon period, and emergency transmission period, which are used opportunistically only for immediate emergency reporting and reliable data transmission. Extensive simulation is performed to evaluate the performance of the proposed scheme. The results reveal that the proposed scheme achieves improved latency and higher emergency packets delivery ratio compared with the conventional IEEE 802.15.4 MAC.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1405-1411
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• 2012

Remote handling manipulators are widely used for performing hazardous tasks, and it is essential to ensure the reliable performance of such systems. Toward this end, tendon-driven mechanisms are adopted in such systems to reduce the weight of the distal parts of the manipulator while maintaining the handling performance. In this study, several approaches for the design of a gripper system for a tendon-driven remote handling system are introduced. Basically, this gripper has an underactuated spring mechanism that is combined with a slave manipulator triggered by a master operator. Based on the requirements under the specified tendon-driven mechanism, the connecting position of the spring system on the gripper mechanism and kinematic influence coefficient (KIC) analysis are performed. As a result, a suitable combination of components for the proper design of the target system is presented and verified.

• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.599-606
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• 2003

As collaborative computing technology goes widespread, interactions among concurrent users are very important, especially in education domain. But existing co-authoring mechanisms and CSCW technologies have limitations for conflict handling. In general, co-authoring tools provide solutions that one or certain users' views are influenced for conflict handling. These solutions have advantages to accomplish rapidly for conflict handling, but other authors' views cannot be affected sufficiently. In this paper, we define the courseware as network structure of instructional units. And we propose co-authoring model for courseware using collaborative conflict-handling mechanism. Using this mechanism, instructors can affect their own viewpoints to the unique courseware. As contents created in these forms have multiple structures. it can provide proper materials according to students' requirements. Therefore, it can provide students with individual learning facilities on online educational systems. Proposed model is useful for courseware based on structured form of document such as XML.

• Safety and Health at Work
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• v.10 no.3
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• pp.327-335
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• 2019

Background: There have been some concerns related to manual handling of large items in industry. Manual handling operations of large sheet metal may expose workers to risks related to efficiency as well as occupational safety and health. Large sheet metals are difficult to move and burdensome to lift/transfer, and handling the sharp sheet edges may result in contact stress and/or cut injuries on the workers. Methods: Through observation, interview, and immersive simulation activities, a few problems related to current handling of sheet metals were identified. A sheet metal trolley-lifter was then designed and fabricated to address these issues. A pilot study on the use of the developed trolley-lifter for handling sheet metals was conducted to compare between the new and traditional handling methods. Results: The pilot study of the trolley-lifter showed promising results in terms of improving the cycle time, manpower utilization, and working postures compared with the traditional handling method. Conclusion: The trolley-lifter offers an alternative solution to automation and a mechanized assistive device by providing a simple mechanism to assist the handling of sheet metals effectively and safely.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.313-317
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• 2000

In this research, a grafting robot with plug in method is used. Plug in method is a method that uses a tapered axis for scion and a tapered hole for stock as processing style of conjugation parts. In the case of handling a grafting seedling, gripping a stem is doing with simple mechanisms of devising to reduce damages to stems. For example, providing cushions between gripper and stem, and fitting a gripper to a stem. Both scions and stocks need cutting, but there is bigger influence for scions than stocks, so problems of cutting scions and special qualities of grippers are necessary to investigate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.1
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• pp.31-35
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• 2003

Switch box is metal box and used for electric wire pipe in building. In manufacturing switch box, we need 5∼6 press machines, 5∼6 dies, 1 tapping machine. and 7∼8 operators. What matters is rise of manufacturing cost and operators' reluctance of working. To solve this problem, we modified the pre-existing die and developed handling mechanism, which leads to improve the manufacturing process. After the research and development, we could reduce the number of machines and workers needed in the process; 2 press machines, 2 dies, 1 tapping machine, and 1 operator. That means we can save labor and the number of operators needed, reduce manufacturing cost, and get the effect of import replacement.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.2
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• pp.67-73
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• 2010

In this study, a camber angle generating mechanism for rear suspension is suggested. An experimental device is implemented and tested. A full vehicle model with camber angle generating device by using ADAMS/Car is modeled. Rear left wheel and rear right wheel have 5 different camber angles in the simulations, respectively. Step steer and pulse steer simulations are carried out for investigating the effects of vehicle handling performance due to camber angle control of rear suspension. According to the results, the camber angle of rear suspension affects the vehicle handling performance during both simulations. Therefore, when the vehicle makes the right turn or left turn, left and right wheel should have the proper orientation for improving the handling performance, respectively.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.6
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• pp.23-29
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• 2011

In this study, a camber angle generating mechanism for front and rear suspension is suggested. An experimental device is implemented and tested. A full vehicle model with camber angle generating device by using ADAMS/Car is modeled. Step steer simulations are carried out for investigating the effects of vehicle handling performance due to camber angle change of front and rear wheel. According to results, the camber angle of rear suspension affects the vehicle handling performance during both simulations. Therefore, when the vehicle makes the right turn or left turn, left and right wheel of front and rear suspension should have the proper orientation for improving the handling performance, respectively.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.492-496
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• 1987

The testing philosophy and control schemes are investigated and applied to construct the Automatic Microwave Leakage Inspection System (AMLIS) . AMLIS is consists of three major parts such as Material Handling Mechanism, Fine Positioning Mechanism and Scanning Mechanism. The material Handling unit is designed to perform loading and unloading microwave oven onto the testing point by pneumatic cylinder and vacuum pump. The Fine positioning part includes X-Y-.THETA. table and distance sensing equipment. The scanning part is composed of five SCARA robots, which traverse X-Y-Z catesian coordinates respectively. The leakage testing probes are placed at the end of this each robot then the path and speed are both controlled via microprocessors. A performance test of this system combined with electric parts and software is done and the basic major function of system are accomplished.