• Journal of Advanced Navigation Technology
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• v.15 no.3
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• pp.449-455
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• 2011

In this paper, Proposed controller prevent compressor surge and reduce the acceleration time of the fuel flow control system for turbo-jet engine. Turbo-jet engine controller is designed by applying fuzzy PI+D control algorithm and make an inference by applying Mamdani's inference method and the defuzzification using the center of gravity method. Fuzzy inference results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller.

• Journal of Advanced Navigation Technology
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• v.21 no.6
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• pp.549-553
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• 2017

The KASS development project, a Korean SBAS launched in 2014, is under development for the APV-1 Class SOL service in 2022. Flight tests should be conducted to analyze development requirements and performance requirements for KASS R & D. However, since the evaluation items have not yet been presented in Korea, FAA and ICAO regulations should be analyzed so that evaluation items for flight testing for KASS development should be structured and comply with international standards. In this paper, we analyze the procedure verification of SBAS for flight test using satellite navigation system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.11
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• pp.968-973
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• 2014

Optionally Piloted Vehicle is one of the UAV development technology and method, which can provide the economic and efficient unmanned system. Existing manned aircraft is evaluated through much flight operations and it can supply the reliable aircraft platform, engine and subsystems for operation. In addition, OPV can be operated both manned and unmanned vehicle to satisfy the mission requirement. under the certain flight conditions. This paper describes main development procedures for automatic flight control system of OPV and summarizes the technical issues and results.

• Journal of Positioning, Navigation, and Timing
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• v.8 no.4
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• pp.175-181
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• 2019

This paper suggests a velocity integration algorithm for Synthetic Aperture Radar (SAR) motion measurement to reduce discontinuity of range error. When using position data from Embedded GPS/INS (EGI) to form SAR image, the discontinuity of the data degrades SAR image quality. In this paper, to reduce the discontinuity of EGI position data, EGI velocity integration is suggested which obtains navigation solution by integrating velocity data from EGI. Simulation shows that the method improves SAR image quality by reducing the discontinuity of range error. INS is a similar algorithm to EGI velocity integration in the way that it also obtains navigation solution by integrating velocity measured by IMU. Comparing INS and EGI velocity integration according to grades of IMU and GPS, EGI velocity integration is more suitable for the real system. Through this, EGI velocity integration is suggested, which improves SAR image quality more than existing algorithms.

• Aerospace Engineering and Technology
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• v.8 no.1
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• pp.172-178
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• 2009

Recently, autopilot is essential to reduce pilot's workload and increase flight safety. Avionics system of the small aircraft also has progressively adopted centralized multi-processor and multi-process computing architectures similar to the integrated modular avionics of B-777. It is increased more and more that importance of the flight control system. In this paper, the performance of the autopilot for the small aircraft has been verified with Hardware-In-the-Loop Simulation(HILS). Also, the autopilot algorithm that is operated in the Flight Control Computer(FCC) for the Fly by Wire(FBW) was verified with PILS and compared with the HILS results for the several commercial autopilots.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.6
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• pp.149-157
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• 2011

In this paper, we propose a new DPCM-based transmission scheme for flight data. The amount of the flight data from LRU to MC has been increased due to the emergence and development of avionics systems and functions. It becomes a serious issue for satisfying the hard real-time processing required in the MC. In order to solve this problem, we observed the flight data produced by X-Plane simulator and discovered that the most flight data are moderately varied during flight. Based on this fact, a new data format is suggested by modifying that of ARINC-429 protocol in this paper. And the different value of the flight data is transmitted in the proposed scheme. The simulation results show that the proposed scheme achieves 20% data transfer gain compared to the ARINC-429 based transmission method.

• Journal of Advanced Navigation Technology
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• v.9 no.2
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• pp.185-192
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• 2005

The aim of this paper is to analyze handling qualities of tiltrotor aircraft(TR-S4) in helicopter flight mode including hovering and forward flight. Analysis of handling qualities is composed of aircraft response to control inputs that effect on stability and controllability. In short term response analysis, bandwidth is the critical parameter for small amplitude motions since it relates to the ability of a pilot to crisply start and stop maneuver. The handling qualities of TR-S4 in helicopter mode are analyzed with a SAS and an attitude controller and are satisfied level 1 in almost criteria with simulation of TR-S4 6-DOF nonlinear model.

• Journal of Advanced Navigation Technology
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• v.19 no.1
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• pp.1-6
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• 2015

Due to the rapid increase in air traffic worldwide, ICAO has replaced the existing navigation equipment with equipment based on satellite navigation. As a part of that work, ICAO was planning to replace conventional takeoff and landing service using ILS with GBAS. Unlike ILS, GBAS which uses precision approach service inducing aircraft to airport and satellite based augmentation system providing precise position information service surrounding airport is capable of providing a required performance by only a system, regardless of the number of systems, and has an advantage that it is possible curved approach. In this paper, fuel reduction of ILS approach procedures and GBAS curved approach procedures is estimated and determined by flight test in Taean Airport.

• Journal of Communications and Networks
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• v.17 no.3
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• pp.286-295
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• 2015

Avionic databuses fulfill a critical function in the connection and communication of aircraft components and functions such as flight-control, navigation, and monitoring. Ethernet-based avionic databuses have become the mainstream for large aircraft owning to their advantages of full-duplex communication with high bandwidth, low latency, low packet-loss, and low cost. As a new generation aviation network communication standard, avionics full-duplex switched ethernet (AFDX) adopted concepts from the telecom standard, asynchronous transfer mode (ATM). In this technology, the switches are the key devices influencing the overall performance. This paper reviews the avionic databus with emphasis on the switch architecture classifications. Based on a comparison, analysis, and discussion of the different switch architectures, we propose a new avionic switch design based on a time-division switch fabric for high flexibility and scalability. This also merges the design concept of space-partition switch fabric to achieve reliability and predictability. The new switch architecture, called space partitioned shared memory switch (SPSMS), isolates the memory space for each output port. This can reduce the competition for resources and avoid conflicts, decrease the packet forwarding latency through the switch, and reduce the packet loss rate. A simulation of the architecture with optimized network engineering tools (OPNET) confirms the efficiency and significant performance improvement over a classic shared memory switch, in terms of overall packet latency, queuing delay, and queue size.

• Journal of IKEEE
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• v.16 no.2
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• pp.145-152
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• 2012

This paper is the Software Hazard Analysis (SWHA) which will study the managerial process and the technical methode and techniques inherent in the performance of software safety task within the Military Aircraft System Safety program. This SWHA identifies potential hazardous effects on the software intensive systems and provides a comprehensive and qualitative assessment of the software safety. The purpose of this paper is to identify safety critical functions of software in Military A/C. The identified software hazards associated with the design or function will be evaluated for risks and operational constraint to further improve the software design requirement, analysis and testing efforts for safety critical software. This common SWHA, the first time analysis in KOREA, was review all avionics OFP(Operational Flight Program), and focus only on software segments which are safety critical. This paper provides a important understanding between the customer and developer as to how the software safety for the Military A/C will be accomplished. It will also provide the current best solution which may as one consider the necessary step in establishing a credible and cost-effective software safety program.