• Journal of Advanced Navigation Technology
• /
• v.15 no.6
• /
• pp.977-985
• /
• 2011

Airborne separation assurance is a key requirement for Free Flight Airspace operations, This paper study the feasibility of airborne separation assurance for free flight Airspaces operations by evaluating the efficiency measurement models. Three qualitatively different methods are utilized; one based Ground and Air conflict probability model, other based Dynamic Density model. the other based Direct operating cost model. The evaluation is Direct Operating Cost model and Two metrics are utilized for the efficiency measurements; airborne separation assurance performed quite well in the Free Flight evaluation; (1) 2 scenario of the conflict situations are resolved; (2) The MD-80 flight peformed separation assurance and efficiency, Not only appling for geometric method algorithm is more efficiently than potential method, but also the most efficiently geometric combined method.

• Journal of Institute of Control, Robotics and Systems
• /
• v.12 no.7
• /
• pp.621-630
• /
• 2006

The T-50 advanced trainer aircraft combines advanced aerodynamic features and a fly-by-wire flight control system in order to produce a stability and highly maneuverability. The flight control system both longitudinal and lateral-directional axes to achieve performance enhancements and improve stability. The T-50 employs the RSS concept in order to improve the aerodynamic performance in longitudinal axis and the longitudinal control laws employ the dynamic inversion with proportional-plus-integral control method. And, lateral-directional control laws employ the blended roll system both beta-betadot feedback and simple roll rate feedback with proportional control method in order to guarantee aircraft stability. This paper details the design process of developing lateral-directional control laws, utilizing the requirement of MIL-F-8785C and MIL-F-9490D. And, this paper propose the analysis of aircraft characteristics such as dutch-roll mode, roll mode, spiral mode, gain and phase margin about gains for lateral-directional inner loop feedback.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.18 no.4
• /
• pp.21-29
• /
• 2010

The main purpose of this study is to obtain linear models for the design of automatic flight controller in order to operate the Light Sport Aircraft as unmanned air vehicle. Flight test equipments installed on the aircraft to acquire flight test data are described and maneuvers for practical speed calibration are introduced. Parameters for the linear models of lateral and longitudinal motion are estimated by the Output error method as well as trim data analysis using the flight test data. Simulated data using the estimated parameters is shown to agree well with the measurement data. Estimated parameters obtained for several flight conditions can be used to improve the aerodynamic database of the simulation program.

• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.11
• /
• pp.913-919
• /
• 2005

An advanced method of Relaxed Static Stability (RSS) is utilized for improving the aerodynamic performance of modem version supersonic jet fighter aircraft. The flight control system utilizes RSS criteria in both longitudinal and lateral-directional axes to achieve performance enhancements and improve stability. Standard CLDA (Control Law Design and Analysis) process is provided that reduce the development period of the flight control system. In addition, if this process is employed in developing flight control laws, it reduces the trial and error development and verification of control laws. This paper details the design process of developing a flight control law for the RSS aircraft, utilizing military specifications, linear and nonlinea, analysis using XMATH and ATLAS(Aircraft, Tim Linear and Simulation), handling quality tests using the HQS (Handling Quality Simulator), and real flight test results to verify aircraft dynamic flight responses.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.14 no.2
• /
• pp.213-221
• /
• 2011

Avionics system tends to be designed to have the integrated architecture, and it is getting difficult and complex to verify the flight-critical function because of sophisticated structure. In Korean Utility Helicopter, mission computer acts as the MUX Bus Controller to handle the data from both communication, identification, mission/display and survivability equipment inside Mission Equipment Package and aircraft subsystems such as fuel system and electrical system while it is interfacing with Automatic Flight Control System and Full-Authority Digital Engine Control via ARINC-429 bus. The Flight Displays which is classified as flight-critical function in aircraft is implemented on Primary Flight Display after mission computer processes data from AFCS in order to generate graphics. This paper defines the flight-critical function implemented in mission computer for KUH, and presents the static and dynamic test procedures which is performed on System Integration Laboratory along with Playback Recorder prior to flight test.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.953-956
• /
• 2017

This paper introduces general applications of vehicle's dynamic pressure information which is estimated during the flight. And a method to estimate the dynamic pressure for a high speed vehicle is suggested to sustain reliability of the flight under a high estimation accuracy of the information. The presented method is straightforward with simple relations of the compressible flow but is a still merited idea employed for the high speed vehicle control scheme with great accuracy.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.33 no.8
• /
• pp.56-64
• /
• 2005

It is prerequisite that we have to fomulate the nonlinear mathematical modeling to design the guidance and control system of rotorcraft-based unmanned aerial vehicle using a small-scaled commercial helicopter. The small-scaled helicopters are very different from the full-scale helicopters in dynamic behavior such as high rotation speed and high frequency dynamic characteristics. In this paper, the formulation of the mathematical model of the small-scaled helicopter to minimize the complexity is presented by component and source build-up approach. It is linearized at the trim condition of hovering and forward flight and analyzed the flight modes. The results of this approach have general trends but a little difference. To verify this approach, it is necessary to compare this theoretical model with experimental results by system identification using flight test as a next research topic.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.47 no.4
• /
• pp.61-68
• /
• 2010

Appling high technology of aerospace to automobile, so it is able to progress safety which is a goal of future automobile and to approach development of self-control automobile. This is realized dynamic model of airplane at DFCS(Digital Flight Control System). The DFCS calculates control values for self-control flight. If this high technology applies to automobile, then it is able to be maneuvered automobile like UAV's self-control flight. In this paper is reanalyzed automobile dynamic applied load control model used high-tech of airplane. It analyzes riding comfortable according to movement of automobile using the load control model, presents method of solution for improvement riding comfortable and presents example of self-control system used the load control model for self-control driving.

• Journal of Institute of Control, Robotics and Systems
• /
• v.10 no.2
• /
• pp.139-144
• /
• 2004

The flight control system designed for an unmanned airship, which is under development by KARI, is in reduced. First, the dynamic characteristics of the airship are addressed, which are fairly different from those of the nominal aircraft. In order to implement autonomous flight for the unmanned airship, flight control logic is designed including autopilot and guidance law. The autopilot is designed under consideration of the velocity region of the unmanned airship. The guidance laws are implemented in main operational modes such as point navigation, station keeping and spiral up/down for emergency return. Their simulation results are also presented in order to validate performances of the flight control system.

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.1659-1662
• /
• 1997

The objective of this paper is to estimate the aerodynamic derivatives of a single turbo-prop aircraft at a specified flight condition for the best deduction of the dynamic characteristics using modified maximum likelihood estimation method whcih is known to be unbiased, efficient, and consistent. The flight test data necessary to the estimation of aerodynamic derivatives is obtained by implementing the six degree of freedom nonlinear flight simulation to consider the effects of several control input types, control deflection amplitudes, and intensity of turbulence. The simulated data is added with the measurement noise, which is regarded as the actual flight test data.