• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
• /
• pp.105-108
• /
• 1993

This paper is concerned with a two-degree-offreedom control system design for a flexible arm, a two-degree-of-frecdom control system can achieve a robust stability specification and a control performance specification independently. By this property we improve the control performance with maintaining the same robust stability level as that of the onc-dcgree-of-freedom control system. At First we design a two-degree-of-fteedom control system which includes a feedforward controller and a feedback controller. The feedforward controller can be given by specifying a transfer function of a dcsired closed-loop model. We obtain a feedback controller by solving a mixed sensitivity problem. Several numerical results show that two-degree-of-freedom control systems acheive a better control performance than that of one-degree-of-freedom control systems.

• 한국정밀공학회지
• /
• 제5권2호
• /
• pp.43-55
• /
• 1988

The control system of a drum boiler is very complex since the evaporization process in the boiler is a multivariable system which is affected one another. This study is concerned with the dynamic characteristics of the boiler process and improving methods of performance of a drum boiler control system. The PID control with feedforward of disturbances and the optimal regulator are compared, and the effects of control parameters on the performance of a boiler control system are investigated. From simulation, it is found that profer adjustment of control parameters significant improvement of response and that performance of a optimal regulated control system is better than that of a conventional PID control system.

• 전자공학회논문지C
• /
• 제34C권12호
• /
• pp.9-19
• /
• 1997

This paper describes the design and FPGA implementation of a system control unit within a multiprocessor chip which can be used as a node processor ina massively parallel processing (MPP) caches, memory management units, a bus unit and a system control unit. Major functions of the system control unit are locking/unlocking of the shared variables of protected access, synchronization of instruction execution among four integer untis, control of interrupts, generation control of processor's status, etc. The system control unit was modeled in very high level using verilog HDL. Then, it was simulated and verified in an environment where trap handler and external interrupt controller were added. Functional blocks of the system control unit were changed into RTL(register transfer level) model and synthesized using xilinx FPGA cell library in synopsys tool. The synthesized system control unit was implemented by Xilinx FPGA chip (XC4025EPG299) after timing verification.

• Journal of Biosystems Engineering
• /
• 제20권3호
• /
• pp.288-298
• /
• 1995

In greenhouse vegetable, the automatic control in cultivating environment has been projected as a national business ; especially a countermeasure against the settlement of UR negotiation. Because it makes possible to manage a large greenhouse with family-hands and to expect the betterment of quality and the increasement of harvest in crops. In the course of carrying the workout, however, there are many problems with the overall control system with computers as well as the individual systems for environment control because of hardware and software problems : especially the shortage of data for development of the system is most serious. Among the many problems for development of the automatic control system, the automations of irrigation, liquefied fertilizer and chemical solution, mixing and ventilation, etc and the development of the general automatic controller system for environment control in greenhouse are studied, which requires a lot of tabors. The results are summarized as follows ; 1. In moisture control by the soil moisture meter, the error was shown 10 % in the beginning irrigation point and 19 % in the stop irrigation point. 2. The supply of liquefied fertilizers with the irrigation system was excellent by setting the operating time and the mixing ratio. 3. The developed chemical spraying system was operated well, but not perfect in nozzle positions. 4. The cucumber was cultivated properly with the trickle irrigation system. 5. The developed controller for the automatic control system in greenhouse was remarkable in the part of hardware, but more researches are needed in the part of software.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.1792-1795
• /
• 1997

It is difficulte to control in the flow system because there are many disturbance. So it is impossible to control delicately sometimes by PI or PID. In this paper, we study on the application of intellignet control algorithms such as 2DOF PID control, neural network, Fuzzy contro, Relay feedback to the flow control system. the resultings are 2DOF-PID control is more good response.

• 제어로봇시스템학회논문지
• /
• 제9권12호
• /
• pp.994-1000
• /
• 2003

A new relative motion control methodology for a following system to an independent leading system is proposed for controlling relative position, velocity, and tension etc. It is based on maintaining minimum relative error between two independent systems. The control command of the following system to a leading system is generated by adding the current command and the output of the relative error compensation. The proposed control method is implemented on the experimental equipment which is a wire winding-unwinding system to control the tension of the line. The results show the unwinding system(follower) following the independent motion of the winding system(leader) to control the constant tension of the line in order to keep the roller dancer in reference position. The relative motion control method proposed in this paper can be applied to high precision equipment for unwinding and winding fine wire, fine fiber, and tape etc.

• Journal of Biosystems Engineering
• /
• 제24권5호
• /
• pp.383-390
• /
• 1999

When a tractor travels slope lands, problems of operator safety and the reduction of job efficiency usually occur. Therefore, maintaining the tractor body being horizontal is critical to improve the security of traveling and the job performance. An experiment was made in a soil bin using the experimental model system built and equipped with a leveling control system. Adaptability of the control system was tested and investigated by analyzing system response in time and frequency domains. Control response time of hydraulic cylinder with 10lpm flow rate on a step input of 10$^{\circ}$slope was about 0.42sec. And it showed a linearly increasing trend without any hunching state. A steady state error of 0.6$^{\circ}$occurred but it was negligible. The hydraulic control system showed a little phase differences within the range of 0.4Hz input frequency. The experimental model showed that implementation of the proposed tractor control system to on slope lands tractor was feasible.

• 제어로봇시스템학회논문지
• /
• 제14권5호
• /
• pp.502-510
• /
• 2008

UAVs(Unmanned Aerial Vehicles) have many applications in military and commercial areas. The flight control system of UAVs is more important than manned aircraft's because the mission of UAVs must be operated without a human pilot. But very heavy and expensive navigation system makes it difficult to develop UAV flight control system. In this research, GPS/IMU integrated navigation filter was developed for light weight/low cost flight control system of small UAVs. With this navigation filter, full flight control system which has real time operating capability has been developed. The performance of the flight control system is basically checked by HILSIM (Hardware In the Loop SIMulation). Finally, the flight control system is verified by showing performance test result under real flight environment.

• Journal of Electrical Engineering and Technology
• /
• 제8권5호
• /
• pp.1040-1048
• /
• 2013

In this paper, a sensorless pitch angle control method for a wind generation system is suggested. One-step-ahead prediction control law is adopted to control the pitch angle of a wind turbine in order for electric output power to track target values. And it is shown that this control scheme using the inverse dynamics of the controlled system enables us to predict current wind speed without an anemometer, to a considerable precision. The inverse input-output of the controlled system is realized by use of an artificial neural network. The proposed control and wind speed prediction method is applied to a Double-Feed Induction Generation system connected to a simple power system through computer simulation to show its effectiveness. The simulation results demonstrate that the suggested method shows better control performances with less control efforts than a conventional Proportional-Integral controller.

• 제어로봇시스템학회논문지
• /
• 제6권3호
• /
• pp.263-272
• /
• 2000

In this paper we give some geometric condition for a stochastic nonlinear system and we propose a control method for a stochastic nonlinear system using neural networks. Since a competitive learning neural networks has been developed based on the stochastcic approximation method it is regarded as a stochastic recursive filter algorithm. In addition we provide a filtering and control condition for a stochastic nonlinear system called the perfect filtering condition in a viewpoint of stochastic geometry. The stochastic nonlinear system satisfying the perfect filtering condition is decoupled with a deterministic part and purely semi martingale part. Hence the above system can be controlled by conventional control laws and various intelligent control laws. Computer simulation shows that the stochastic nonlinear system satisfying the perfect filtering condition is controllable and the proposed neural controller is more efficient than the conventional LQG controller and the canonical LQ-Neural controller.