• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.200-202
• /
• 2004

This paper deals with the real-time monitoring and control system using PC, PDA(Win CE embedded device) and PCS(based BREW platform). The camera attached to the server captures the moving target, and the captured frame of color image is encoded in JPEG for image compression at the server. The client(PC, PDA, PCS) receives the image data from the remote server and the received image is decoded from decompression. We use the TCP/IP protocol to send the image frames. The client can control the position of the camera by sending the control command to the server. Two DC servo motors for the camera are controlled in any directions, up-down and left-right, by the controller which is communicating with the server via the serial communication to get the control command. In this way, on the client we can monitor the moving images at the server and also control the position of the camera.

• Proceedings of the KIEE Conference
• /
• 1991.07a
• /
• pp.555-558
• /
• 1991

The IESF(Integral Error and State Feedback) controller, which incorporates state feedback as a modern control scheme and integral action as a classical control scheme, has better performance than that of the conventional PID controller in linear time-invariant systems. The IESF controller requires the measurement of all the state variables. But, unfortunately, it may be difficult or impossible to measure all state variables in many applications. And the IESF controller is applicable only to pole-assignable linear time-invariant system without time delay. In this paper, new IESF controller structure was proposed which performs feedback with only measurable state variables. In order to estimate the unmeasurable state variables. It was adopted the filter mode by full-order obserber. The good performance and effectiveness of the proposed controller was confirmed by computer simulation.

• Proceedings of the KIEE Conference
• /
• 1994.07a
• /
• pp.582-584
• /
• 1994

A sinusoidal rotatory chair system using a self-tuning and following control by a fuzzy was designed to evaluate the vestibular function and to apply to a robot driving power system. The experimental results by the sinusoidal rotatory chair system were pretty good and whitch had smaller then ${\pm}210$ pulse error on the ${\pm}810^{\circ}$ sinusoidal rotation at 0.12 Hz by using a 850W DC servo motor. As a results, the sinusoidal rotatory chair system may be useful to evaluate the vestibular function in the field of medicine, and it can be used to robotics or a numerical control system (NC) on the industry if the the obtained control method and the system are adapted for a channel.

• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.4
• /
• pp.111-118
• /
• 1995

This paper presents the modified fuzzy-compensated PID(FCPID) control, which involves adding the compensator to an existing PID controller, to improve the performances of the systems. Compared to a conventional PID control and a fuzzy logic control(FLC), the proposed control scheme has superior performance. Experimental results of an actual implementation of the modified PC-based FCPID controller on the DC servo-motor demonstrate considerable improve- ment of the performance of the existing FCPID control by monitoring the scaling factor. They show faster responses and smaller overshoots than the conventional FCPID control scheme for the various reference inputs and the robustness to the loads.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2007.05a
• /
• pp.300-305
• /
• 2007

This study developed a human robot master arm, which has a structure similar to the human arm, with the object of taking over human works. The robot arm was structured to reproduce human actions using three axes on each of the shoulder and the wrist based on mechanics, and the actuator of each axis adopted an ordinary DC motor. The servo system of the actuator is a one body type employing an amp for electric power, and it was designed to be small and lightweight for easy installation. We examined the posture control characteristics of the developed robot master arm in order to test its interlocking, continuous notions and reliability.

• Proceedings of the KIEE Conference
• /
• 1988.11a
• /
• pp.76-79
• /
• 1988

The sliding mode control in an effective method to eatablish robustness against parameter variation and disturbance. But. In sliding mode strategy, the control function is discontinuous on the hyperplane. However the discontinuous change in control structure caves the controller input to chaffer and gives non-zero steady state error. Consequently, a multiloop feedback control system supplemented by a complelmentary controller is used to improved the drive performence of a DC servo motor and reduce sensitivity to parameter variation, nonlinear effects, and other disturbances.

• Proceedings of the KIEE Conference
• /
• 1988.11a
• /
• pp.426-429
• /
• 1988

A Microprocessor Based Digital Control System is inherently contained a control lag for processing the control program and a data detection time lag. This two types of time lag may cause the system to become unstable. In this paper proposed predictive state observer is used to solve the two time lag problems. I-P control algorithm is used to attain deadbeat response by adjusting the observer gain to overcome the parameter variation or with disturbance. The speed response shows good performance through computer simulation.

• Proceedings of the KIEE Conference
• /
• 1999.11c
• /
• pp.552-554
• /
• 1999

In this paper, a robust control system with the disturbance observer is proposed for BLDC servo system. The overall control system consists of the speed controller which is implemented with PI controller and the disturbance observer with free parameters. The proposed control system is designed the command input response and the closed loop characteristics independently by using two-degrees-of-freedom concept, so it can improve the closed loop characteristics with no influence on the command input response. The effective suppression of disturbance with the observer improves the characteristics of the closed loop of the system. And also, by fluting the bandwidth of free parameters, measurement noise is considered. To verify the better performance of the proposed control system than that of the conventional PI controllers, the performance of the controller is analyzed theoretically and some simulation results are presented.

• Proceedings of the KIEE Conference
• /
• 1999.11c
• /
• pp.588-590
• /
• 1999

In this paper the design method of a fuzzy logic controller with a genetic algorithm is proposed. Fuzzy logic controller is based on linguistic descriptions(in the form of fuzzy IF-THEN rules) from human experts. The auto-tuning method is presented to automatically improve the output performance of controller utilizing the genetic algorithm. The GA algorithm estimates automatically the optimal values of scaling factors and membership function parameters of fuzzy control rules. Controllers are applied to the processes with time-delay and the DC servo motor. Computer simulations are conducted at the step input and the output performances are evaluated in the ITAE.

• Proceedings of the ESK Conference
• /
• 1997.04a
• /
• pp.145-149
• /
• 1997

General joystick using spring only has a vibration when operaor drops the joystick. If it is used as input of motorized wheelchair, its system have a serious problem which operator fall into dangerous situation. Therefore, In this paper proposed non-vibration joustick which control a motorized wheelchair. Non-vibration joystick was designed which return to origin point when operator drops joystick by mistake. Reflected force of non- vibration joystick is defined as addition displacement and variation rate. And each parameter has elasticity of spring and viscosity of DC servo motor. Through simulation for virtual environment, we found two coefficient to return origin point smoothly when a disabled person drops the joystick. In case of larger elastic coefficient of spring than viscous coefficient, we confirmed the result has the equal vibration of general joystick (under-damping). In opposite case, joystick returned to origin point with excessive force. As a application of non-vibration joystick, we experimented wall-following controlling. In this trial, we corroborated that joystick follows smoothly around the corridors.