• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.1304-1307
• /
• 1996

In this paper, we present a robust Two Degree of Freedom (TDF) $H_{\infty}$ controllers for a missile system. The feedback controller is designed to meet robust stability and disturbance rejection specifications while the prefilter is used to improve the robust model matching properties of the closed loop system. As the perturbed model, we use the normalized coprim factor perturbations. These controllers are designed using $H_{\infty}$ optimization procedures, and applied to a missile model via simulation.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.6
• /
• pp.809-818
• /
• 2019

Since January 1, 2020, the International Maritime Organization (IMO) has put in place strong regulations to reduce air pollution caused by ships by lowing the upper limit of ship fuel oil sulfur content from 3.5% to 0.5% for ships passing through all sea areas around the world. Although it is important to reduce air pollutants by using fuel oil with low sulfur content, reducing the amount of energy waste through the economic operation of a ship can also help reduce air pollutants. Ships can follow designated routes accurately even under the influence of noise using autopilot systems. However, regardless of their quality, the performance of these systems is af ected by noise; heading angles with added measurement noise from the gyroscope are input into the autopilot system and degrade its performance. A technique to solve these problems reduces noise effects through the application of a Kalman filter, which is widely used in condition estimation. This method, however, cannot completely eliminate the effects of noise. Therefore, to further improve noise removal performances, in this study we propose a better denoising method than the Kalman filter technique by applying a multi-layer perceptron (MLP) in forward direction motion and a Kalman Filter in rotation motion. Simulations show that the proposed method improves forward direction motion by preventing the malfunction of a rudder more so than merely using a Kalman Filter.

• KEPCO Journal on Electric Power and Energy
• /
• v.4 no.2
• /
• pp.115-123
• /
• 2018

Various types of robots running on power transmission lines have been developed for the purpose of line patrol monitoring. They usually have complex mechanism to run and avoid obstacles on the power line, but nevertheless did not show satisfactory performance for going over the obstacles. Moreover, they were so heavy that they could not be easily installed on the lines. To compensate these problems, flying robots have been developed and recently, multi-copter drones with flight stability have been used in the electric power industry. The drones could be remotely controlled by human operators to monitor power distribution lines. In the case of transmission line patrol, however, transmission towers are huge and their spans are very long, and thus, it is very difficult for the pilot to control the patrol drones with the naked eye from a long distance away. This means that the risk of a drone crash onto electric power facilities always resides. In addition, there exists another danger of electromagnetic interference with the drones on autopilot waypoint tracking under ultra-high voltage environments. This paper presents a patrol monitoring plan of autopilot drones for power transmission lines and its field tests. First, the magnetic field effect on an autopilot patrol drone is investigated. Then, how to build the flight path to avoid the magnetic interference is proposed and our autopilot drone system is introduced. Finally, the effectiveness of the proposed patrol plan is confirmed through its field test results in the 154 kV, 345 kV and 765 kV transmission lines in Chungcheongnam-do.

• Transactions on Control, Automation and Systems Engineering
• /
• v.4 no.4
• /
• pp.264-269
• /
• 2002

In this paper, Η$_{\infty}$ depth and course controller of an AUV(Autonomous Underwater Vehicle) using Η$_{\infty}$ servo control is proposed. The Η$_{\infty}$ servo problem is formulated to design the controllers satisfying a robust tracking property with modeling errors and disturbances. The solution of the Η$_{\infty}$ servo problem is as fellows: first, this problem is modified as an Η$_{\infty}$ control problem for the generalized plant that includes a reference input mode, and then a sub-optimal solution that satisfies a given performance criteria is calculated by LMI(Linear Matrix Inequality) approach. The Η$_{\infty}$ depth and course controller are designed to satisfy with the robust stability about the modeling error generated from the perturbation of the hydrodynamic coefficients and the robust tracking property under disturbances(wave force, wave moment, tide). The performances of the designed controllers are evaluated with computer simulations, and finally these simulation results show the usefulness and application of the proposed Η$_{\infty}$ depth and course control system.

• Journal of Advanced Navigation Technology
• /
• v.24 no.6
• /
• pp.515-520
• /
• 2020

The development of autopilot system and flight management system (FMS) equipment in today's aircraft navigation can be attributed to the reduction of pilots' workload and the navigation safety. The effect of autopilot and FMS equipment is greater, especially in heavy airport traffic or complicated of the departure. However, some airport specific departure procedures result in an uncommanded turn event due to an error in the FMS, causing aircraft to deviate from the center line of the route. With most departure procedures requiring area navigation (RNAV) operation, pilot situation awareness and corrective action are the only ways to minimize aircraft deviation to maintain the safety of area navigation. Through analysis of the occurrence status of the uncommended turn event by aircraft type, airport and flight phase, and comparative analysis of the survey results of foreign airlines and the airlines self-reduction plan with the aircraft manufacturer's corrective action, it is intended to give implications for the need for more fundamental measures to prevent recurrence of such events.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.50 no.12
• /
• pp.857-866
• /
• 2022

Fixed-wing UAVs have long endurance and range capabilities compared to other aerial platforms. These advantages led fixed-wing UAVs to become a popular platform for reconnaissance missions in the military. In this research, we modeled fixed-wing UAVs, including the landing gear model and developed a guidance and control system for flight control computers to construct a HILS environment. We also developed an autopilot system that includes automated take-off, cruise, and landing control for UAVs. We also retrived the Aerodynamic coefficients an UAV using Datcom and AVL software and used them for 6 degrees of freedom modeling. The Flight control computer calculates guidance commands using the Carrot chasing guidance law after distinguishing the condition of the UAV based on 16 pre-defined flight modes and calculates control inputs using Nonlinear Dynamic Inversion (NDI) control scheme. We used RTNngine to integrate the Simulink model and flight control computer for HILS environment formulation.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.44 no.12
• /
• pp.1035-1042
• /
• 2016

By using commercial flight simulation game engine, X-Plane, we have studied QTG(Qualification Test Guide) generation that can satisfy FTD level 5. Flight model is SR-20 of Cirrus. In list of QTG, There are some items to measure control forces. therefore, we have installed CLS(Control Loading System) to flight control devices in order to make it possible to measure control forces. We made Autopilot function externally to make flight model in trim conditions because X-Plane don't provide internal trim routine function. In addition to develop an algorithm, it can automatically perform the test. To avoid the inconvenience to control as it was to be carried out in same conditions. In case of FTD level 5, it is possible to use alternative data sources not only real flight data. By using these alternative data sources, all test results satisfy a scope given by CFR Part 60.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10a
• /
• pp.1076-1079
• /
• 1993

A fuzzy digital controller is combined an autopilot system for compensating the cross coupling effect of the induced roll due to the dynamic characteristic of three fin torpedo. However the utilization of fuzzy chip has many interfacing problems with typical microprocessors of the guidance and control unit. Since a fuzzy digital controller on a microprocessor uses a finite word length A/D converters arul D/A converters, ADC and DAC may generate nonlinear effects such as deadband and limit cycle phenomena. In this paper, the robustness of fuzzy digital controller is tested with ADC a finite word length.

• ICROS
• /
• v.7 no.6
• /
• pp.10-17
• /
• 2001

본 논문에서는 훈련용과 연구용 시뮬레이터들에서 차량조종 및 자동조종(autopilot) 시스템들을 시뮬레이션하기 위하여 공통적으로 사용되는 기술들을 소개한다. 여기서 언급하는 차량 조종 시스템들은 고정익기와 회전익기의 비행제어시스템은 물론 지상차량의 조종 시스템들을 모두 포함한다. 본 논문은 다양한 유형의 비행 및 지상차량 조종 시스템들에 대한 검토로 시작된다. 다음으로 차량조종 및 자동조종 시스템들의 시뮬레이션과 모델링, 조정 부하(control loading)라 통상 일컫는 조종감(control feel)의 시뮬레이션, 조종계통 모델링툴 시스템 통함 및 시스템 성능 비준 등의 주요 주제들이 이어진다.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.141.3-141
• /
• 2001

Since 1990´s, there has been many researches for the development of the Unmanned Aerial Vehicle (UAV). Especially, for the development of digital electronics, the technologies of UAV toward to the miniaturization low-cost, and high reliability. Therefore, recent trends for the development of UAV are focused on the development modern Flight Control System (FCS). In this paper, focusing on the FCS, the development process for Sejong Unmanned Research Vehicle -1 (SURV-1) from design to flight test is presented.