• International Journal of Aeronautical and Space Sciences
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• v.12 no.3
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• pp.241-251
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• 2011

Most large commercial aircrafts and high performance military aircrafts use fly-by-wire (FBW) or fly-by-light systems to improve their controllability, comfort, and safety. A flight envelope protection technique is used with flight control systems utilizing the FBW technique. Such flight envelope protection systems prevent these aircraft from exceeding the structural/aerodynamic limits and control their surface limits. This is accomplished by predicting the values of the future state variables and adaptively compensating the control action. In this study, the conventional dynamic trim algorithm of the flight envelope protection is modified to increase the method accuracy and to handle cases with multiple variables. Numerical simulation is also performed to verify the performance of the proposed method.

• Journal of Aerospace System Engineering
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• v.10 no.1
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• pp.111-117
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• 2016

A new configuration of tiltrotor UAV previously suggested by Korea Aerospace Research Institute (KARI) for the purpose of increasing the endurance performance in airplane mode flight has extended wings attached to the nacelle and rotated with the nacelle according to the flight modes. In this research, the effectiveness of the extended wing on the enhancement of the endurance performance of KARI tiltrotor UAV (TR60) was analytically investigated based on CFD analysis results. Flight tests and ground tests of measuring the fuel consumption were also conducted to directly compare the endurance performance for the two configurations of TR60 baseline and TR60 extended-wing model.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.11
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• pp.1124-1129
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• 2006

In this paper, in-flight alignment algorithm using UKF is presented for an SDINS aided by SSBL or GPS system under large initial heading error. The EKF usually applied for this task. This approximates the propagation of mean and covariance accurate to first-order only. To overcome this limitation, the unscented transformation that achieves second order approximation is applied to the in-flight alignment. To analyze the performance of the proposed method, simulations for S-type trajectory are carried out. The results show that performance of EKF and UKF are the almost same when the initial heading error is smaller than $30^{\circ}$, but UKF has a better performance for large initial heading error about $45^{\circ}$.

• Journal of Aerospace System Engineering
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• v.1 no.2
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• pp.6-12
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• 2007

Flight modes of automatic flight control system for light general aviation flight deck. Garmin G1000, were realized using Stateflow. In developing aircraft, it is difficult to verify the operational flight program in particular branch statement because developer can not see any visual logical steam. So, Stateflow has been used to visualize logical stream, transition from one flight mode to another flight mode. The performance was approved by applying flight mode transition conditions of G1000 to proposed transition system that is composed of states, switches, events, data and transition conditions. DURMI-II was used as 6-DOF simulation model.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.219-222
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• 1996

Authors ahve developed ALFLEX simulation program which can implement the flight simulation ad control system design of ALFLEX efficiently by using aerodynamic data provided by NAL/NASDA. Then we have designed and example of flight path and altitude control system of ALFLEX. The philosophy of the design method is explained in detail, and a flight simulation result is shown, which verifies the fine performance of the system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.4
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• pp.638-647
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• 1994

This paper describes the real time Hardware-In-the Loop Simulation(HILS) that is an efective tool for design, testing and performance evaluation of the guidanc eflight system. The real time HILS was performed by using a 3-axis flight motion simulator, real time computer, I/O system and flight control system hardware along with the assumed flight trajectory of the guidance flight system. Also, we proved the validity of the real time HILS is the guidance flight system by comparing its simulation results with the software simulation data and telemetry data.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.12
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• pp.1244-1252
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• 2008

This paper presents the analysis results obtained by the flight test of reconfiguration flight control system for an aircraft. The reconfiguration flight control system was designed by using control allocation scheme that automatically distributes the demanded control moments determined by control law to each actual control surface. In this paper, some control allocation algorithms for reconfiguration control of general aircraft with redundant control surfaces are summarized and their performance evaluation results through nonlinear simulation and Hardware-In-the-Loop-Simulation (HILS) test are shown. Also, Unmanned Aerial Vehicle (UAV) system adopted as a platform for the flight test of reconfiguration flight controller and the implementation procedure of reconfiguration flight controller into real-time UAV system were introduced. Finally, flight test results were analyzed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.9
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• pp.783-791
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• 2007

For an access to specified helicopter simulator qualification's level C or FTD(Flight Training Device) level 5 of FAA(Federal Aviation Administration) AC(Advisory Circular) 120-63, the mathematical model of a single rotor helicopter flight dynamics is investigated. From the rotorcraft simulation model validated by evaluation of its flight performance, the feasibility of the flight dynamic model that is selected for its effectiveness has been proved. Thereby the simulation environment for evaluation of helicopter flying quality is established with the development of FTD for training and testing the flight performance.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.7
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• pp.633-643
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• 2005

An unmanned aerial vehicle (UAV) is an aircraft controlled by .emote commands from ground station and/o. pre-programmed onboard autopilot system. A navigation system in the UAV provides a navigation data for a flight control computer(FCC). The FCC requires accurate and reliable position, velocity and attitude information for guidance and control. This paper proposes an ADGPS/INS integrated navigation system for a UAV. The proposed navigation system comprises an attitude determination GPS (ADGPS) receive., a navigation computer unit, and a low-cost commercial MEMS inertial measurement unit(IMU). The navigation algorithm contains a fault detection and isolation (FDI) function fur integrity. In order to evaluate the performance of the proposed navigation system, two flight tests were preformed using a small aircraft. The first flight test was carried out to confirm fundamental operation of the proposed navigation system and to check the effectiveness of the FDI algorithm. In the second flight test, the navigation performance and the benefit of the GPS attitude information were checked in a high dynamic environment. The flight test results show that the proposed ADGPS/INS integrated navigation system gives a reliable performance even when anomalous GPS data is provided and better navigation performance than a conventional GPS/INS integration unit.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.1
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• pp.75-82
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• 2020

To compare and analyze the differences between flight simulation and actual flight among 130 army helicopter pilot training subjects, the correlation analysis was performed first through t-testing and multiple regression analysis of individual characteristics and flight simulation and actual instrument flight training, which were analyzed significantly in the age (a3) and service classification (a5) of the six verification factors. This has been shown to be significant, with no difference between the flight simulator and the actual flight. Second, in order to study the correlation between aircraft types, the flight evaluation (v1) was analyzed as a dependent variable for the performance of the flight simulator (KUH: s2, UH60: s3, AH-1S: s5, UH-1H: s6), and the results of the multiple regression analysis of the flight simulator evaluation (s1) were analyzed, in contrast, as a dependent variable, and in conclusion, the training of the flight simulator provided statistical data on the possibility of replacing the actual flight training, which is thought to contribute to the orientation, budget reduction and aviation safety of the pilot training.