• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.491-494
• /
• 2002

The real-time industrial network often referred to as fieldbus, is an important element for building automated manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices such as sensors, actuators, and controllers. numerous standard organizations and vendors have developed various fieldbus protocols such as Profibus, WorldFIP and Foundation Fieldbus. However, the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multi-vendor products. In order to solve these problems, the computer network technology, especially Ethernet (IEEE 802.3), is being adopted lo the industrial environment. The crucial technical obstacle for Ethernet is that its non-deterministic behavior makes it inadequate for industrial applications where real-time data such as control command and alarm signal hale to be delivered within a certain time limit. Recently, the development of switched Ethernet shows a very promising prospect for industrial application due to the elimination of uncertainties in the network operation resulting in much improved performance. This paper focuses on the application of the switched Ethernet for industrial comm unications.

• Journal of the Korean Society of Safety
• /
• v.15 no.3
• /
• pp.115-123
• /
• 2000

Pneumatic actuators are widely used in a variety of hazardous working environments. Any process that involves pneumatic actuation is also recognized as "eco-friendly". In most cases, applications of pneumatic actuators require only point-to-point control. In recent years, research efforts have been directed toward achieving precise position tracking control. In this study, a tracking position control method is proposed and experimentally evaluated for a linear positioning system. The positioning system is composed of a pneumatic actuator and a 3-port proportional valve. The proposed controller has an inner pressure control loop and an outer position control loop. A PID controller with feedback linearization is used in the pressure control loop to nullify the nonlinearity arising from the compressibility of the air. The position controller is also a PID controller augmented with the friction compensation by a neural network. Experimental results indicate that the proposed controller significantly improves the tracking performance.rformance.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.26 no.10
• /
• pp.1471-1478
• /
• 1989

The optimal-time control of the coordinated motion of two robot manipulators may be of consequence in the industrial automation. In this paper two robot manipulators garsping a common object are assumed to travel a specified Cartesian path and the method how to derive the optimal-time solution is explained. This approach is based on parameterizing the corresponding patn and utilizing the phase-plame technique in the trajectory planning. Also the torques supplied by the actuators are assumed to have some constant bounds. The effectiveness of this approach is demonstrated by a computer simulation using a PUMA 560 manipulator.

• Proceedings of the KIPE Conference
• /
• 1998.10a
• /
• pp.113-118
• /
• 1998

In modern mechatronics new concepts of machines and processes are found by using the collected knowledge of all disciplines and by offering functional solutions. Most of the problems in the field of mechatronics demand technical innovations on the field of actuators, sensors and control methods. It demands also high dynamic drives with power electronics, able to cope with the new requirements. The paper presents some trends and industrial experiences with power components for high dynamic drives.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2006.11a
• /
• pp.319-322
• /
• 2006

The Deep-sea miner system is composed of body, actuators, sensors, and devices for control and monitoring. At present, we are manufacturing the miner's body included actuators and already consisted with off-the-shelf embedded controller. But sensors and those devices were just determined. To previously test performance of embedded controller which manages control and monitoring of miner system, its simulator must be developed for control and monitoring. Hardware-In-the-Loop(HIL) simulation is being increasingly used in industrial applications. This is an effective tool for the evaluation of electric system and drives. In the HIL simulator, we can test and design the control and monitoring system freely without the risk of hardware ruins and the load of expenses. Also the programming software for miner operating is verified on the HIL simulator. In this paper, we introduce the concept of HIL simulator for control and monitoring of deep-sea miner.

• International Journal of Control, Automation, and Systems
• /
• v.6 no.3
• /
• pp.327-338
• /
• 2008

A fault tolerant control system design technique has been proposed and analyzed for managing performance degradation in the presence of multiple faults in actuators. The method is based on a control structure with a model reference reconfigurable control design in an inner loop and command input adjustment in an outer loop. The reduced dynamic performance requirements in the presence of different actuator faults are accounted for through different performance reduced (degraded) reference models. The degraded steady-state performances are governed by the reduced levels of command input. The reconfigurable controller is designed on-line automatically in an explicit model reference control framework so that the dynamics of the closed-loop system follow that of the performance reduced reference model under each fault condition. The reduced command input level is determined to prevent potential actuator saturation. The proposed method has been evaluated and analyzed using an aircraft example against actuator faults subject to constraints on the magnitude and slew-rate of actuators.

• Elastomers and Composites
• /
• v.42 no.3
• /
• pp.159-167
• /
• 2007

Hydraulic actuators are used widely for industrial machinery. The seal made from elastomer is used as a core part of the actuator, NBR(nitrile butadiene rubber) materials with high quality of oil resistance and abrasion resistance is used widely, requiring excellent characteristic of sealing. According to applied circumstances, the actuators for industrial machinery are used under different temperature situations. In this study, three different kinds of NBR, which is Hs70, 80, 90 are determined as one of hydraulic materials. An experimental investigation is performed to confirm the non-linearity under different temperature ($-10^{\circ}C,\;20^{\circ}C,\;80^{\circ}C,\;100^{\circ}C$) situation, material constants for finite element analysis and plastic deformation in accordance with Load-unload.

• Journal of Industrial Technology
• /
• v.28 no.A
• /
• pp.75-80
• /
• 2008

This paper describes the mechanical and control design of a robotic device for providing therapeutic assistance to arm movement following stroke. This is a new robot for arm therapy applicable to the training of activities of daily living in homes and clinics. This instrument has one degrees of freedom, and is equipped with position and force sensors. Repetitive movement can improve movement performance in patients with neurological or orthopaedic lesions. The application of robotics can serve to assist, enhance, evaluate, and document neurological and orthopaedic rehabilitation of movements. The new robot, the mechanical structure, the control circuit, the sensors and actuators and some safety aspects.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.4B no.2
• /
• pp.39-46
• /
• 2004

Modern users demand that the on and off type solenoid actuator should be smaller, lighter in weight, lower in consumption power, and higher in response time. The complete design satisfying such requirements can be achieved when electromagnetic theories and empirical knowledge are combined. This paper presents various types of empirical coefficients essentially needed for optimal design of a solenoid actuator. The values of these empirical coefficients are obtained through extensive experiments over a great length of time for various kinds of solenoid actuators. We have developed a design program that is composed by combination of governing equations and empirical coefficients, and have also manufactured a prototype solenoid actuator based on the final results of the design program. The propriety of the design program and empirical coefficients have been proven by experiments.

• Journal of Industrial Technology
• /
• v.22 no.B
• /
• pp.141-146
• /
• 2002

It becomes common to use computers to control electronic devices and security facilities in newly constructed buildings and house. There are many home application devices in the market which can be controlled by computers. But they are expensive and managed by specialized companies. This paper is focused on personal computers which are available in most homes and can be used to control home electronic appliances and home security facilities. We implemented a home automation server based on Linux. The standard parallel port of personal computer is used to connect sensors and actuators. Therefore, the cost of the server is very low. Moreover, the server is connected to Internet and anywhere we can control and monitor the home security facilities and home automation systems.