• International Journal of Control, Automation, and Systems
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• v.2 no.2
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• pp.238-246
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• 2004

In displaying a virtual wall using a passive haptic device equipped with passive actuators such as electric brakes, unsmooth motion frequently occurs. This undesirable behavior is attributed to time delay due to slowness in the virtual environment update and force approximation due to the inability of a brake to generate torque in arbitrary directions. In this paper a new control scheme called direct control is proposed to achieve smooth display on the wall-following task with a passive haptic device. In direct control, brakes are controlled so that the normal component of a resultant force at the end-effector vanishes, based on the force analysis at the end-effector of the passive haptic device using the passive FME (Force Manipulability Ellipsoid). Various experiments have been conducted to verify the validity of the direct control scheme with a 2-link passive haptic system.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1286-1288
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• 1996

An add/drop control chip for SDH transmission system has been designed in AT&T 0.5um CMOS ORCA FPGA. This device plays an important role in achieving self-healing ring operation which protects against failure. After this device receives each 24-ch AU-3 signals from the west, east, and add parts, it outputs each 24-ch switched signals through the control data of system control port. This device consists of eight sub-part such west/east transmitting part, west/east receiving part, add/drop control part, AIS control part, and CPU interface part. The designed device is capable to ring networks as well as linear networks.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.4
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• pp.560-565
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• 2020

Korea's seaweed is using a method that is not suitable for the automated process and quality are significantly lower than the export volume of 20,000 tons or more. Therefore, in this paper, we improved the existing dry steaming weight control device and electronicized the remote control system and the existing dry steaming weight control device. This is implemented with precise and detailed device, unlike the dry seaweed weight control method using the conventional valve which depends on the user's feeling and experience. Also, because it is a remote control system, it can help to produce seaweed safely even if you don't climb on the machine. The Seaweed weight control device implemented is expected to contribute greatly to the automation process and industrial growth of the steeply growing dry laver production and export industry.

• Proceedings of the Korean Statistical Society Conference
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• 2005.05a
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• pp.197-201
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• 2005

In this article, we will compare the performance of the mean control chart, the median control chart, the transformed mean control chart, the transformed median control chart, and the precedence control chart by simulation study. For control charts with transformed data, Yeo-Johnson transformation is used. Under the in-control condition, ARL's in all control charts coincide with the designed ARL in the normal distribution, but in the other distributions, only the precedence control chart provides the in-control ARL as designed. Under the out-of-control condition, the mean control chart is preferred in the normal distribution and the median control chart is preferred in the heavy-tailed distribution and the precedence control chart outperforms in the short-tailed distribution.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.25-32
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• 2009

This paper proposes the construction of intelligent home network system using Power Line Communication(PLC) technique, which allows for UPnP bridge remote control and monitoring based on TCP/IP. Also, the communication for control module inside intelligent home network systems is designed with Simple Control Protocol (SCP) in which each device is connected to be controlled independently. When new UPnP device is additionally installed in intelligent home network systems, it is monitored through UPnP bridges based on its registered UPnP device information. The device control based on PLC and implementation of each UPnP device are effectively managed by using TCP/IP remote control and it's provided fundamental functions to monitor various device information in the home network.

• Smart Structures and Systems
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• v.19 no.5
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• pp.487-497
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• 2017

Semi-active devices use the building's own motion to produce resistive forces and are thus strictly dissipative and require little power. Devices that independently control the binary open/closed valve state can enable novel device hysteresis loops that were not previously possible. However, some device hysteresis loops cannot be obtained without active analog valve control allowing slower, controlled release of stored energy, and is presents an ongoing limitation in obtaining the full range of possibilities offered by these devices. This in silico study develops a proportional-derivative feedback control law using a validated nonlinear device model to track an ideal diamond-shaped force-displacement response profile using active analog valve control. It is validated by comparison to the ideal shape for both sinusoidal and random seismic input motions. Structural application specific spectral analysis compares the performance for the non-linear, actively controlled case to those obtained with an ideal, linear model to validate that the potential performance will be retained when considering realistic nonlinear behaviour and the designed valve control approach. Results show tracking of the device force-displacement loop to within 3-5% of the desired ideal curve. Valve delay, rather than control law design, is the primary limiting factor, and analysis indicates a ratio of valve delay to structural period must be 1/10 or smaller to ensure adequate tracking, relating valve performance to structural period and overall device performance under control. Overall, the results show that active analog feedback control of energy release in these devices can significantly increase the range of resetable, valve-controlled semi-active device performance and hysteresis loops, in turn increasing their performance envelop and application space.

• Journal of Drive and Control
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• v.12 no.3
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• pp.11-17
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• 2015

An intelligent deburring control (IDC) device is used to control the constant force for a deburring tool mounted on the end-effector of a robotic arm. This device maintains a constant contact force between the deburring tool and the workpiece in order to provide a good deburring performance. In this paper, we build a mathematical model in Matlab/Simulink to estimate the force control mechanism of the pneumatic system for the IDC device. The Simulink blocks are built for each separate part and are linked into an integrated simulation system. Such a model also relies on the effects of the flow rate through the valve, air compressibility in the cylinder, and time delay in the pressure valve. The results of the simulation are compared to a simple experiment in which convenient math modeling is performed. These results are then used to optimize the mechanical design and to develop a force control algorithm for the pneumatic cylinder.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.5
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• pp.354-360
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• 2003

For the convenient use of high performance microprocessor in motor control, peripheral devices are needed for converting its control signals to compatible ones for motor drive. Customized devices are not plentiful far these purposes and their functions do not usually satisfied designers specification. The designers used to implement these functions on FPGA or CPLD using hardware description language. Then, in this case unessential programs are needed for control the peripherals. In this paper, a unified device model that links peripheral devices, including especially the pulse width modulation controller and the quadrature encoder interface device, to an interrupt controller is proposed. Advanced functions of peripherals could be achieved by this model and unessential programs can be simplified. Block diagrams and flowcharts are presented to illustrate the advanced functions. This unified device was designed using VHDL. The simulation results were presented to demonstrate the effectiveness of the proposed scheme.

• Journal of Aerospace System Engineering
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• v.3 no.3
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• pp.13-16
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• 2009

Aircraft flight control surfaces which are one of the most important elements of safety allow a pilot to adjust and control the aircraft's flight attitude. This paper is described of the control surface deflection angle measuring device. Data analysis through ground test and flight test can provide reliability of this device using the present system. It is also shown that measuring system is capable of detecting failure of control surfaces.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.422-427
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• 2006

This paper presents force-feedback control performance of a haptic device in virtual environment of minimally invasive surgery(MIS). As a first step, based on an electrorheological(ER) fluid and spherical geometry, a new type of master device is developed and integrated with a virtual environment of MIS such as a surgical tool and human organ. The virtual object is then mathematically formulated by adopting the shape retaining chain linked(S-Chain) model. After evaluating reflection force, computational time, and compatibility with real time control, the virtual environment of MIS is formulated by interactivity with the ER haptic device in real space. Tracking control performances for virtual force trajectory are presented in time domain, and theirtrackingerrorsareevaluated.