• Current Industrial and Technological Trends in Aerospace
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• v.7 no.1
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• pp.32-42
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• 2009

Required system and technology for the civil helicopter and the military helicopter are almost similar. A lot of mount helicopters are converted from military to civil, or converted oppositely, or new developed considering civil-military dual use in order to reduce development cost and period. In the case of converting the military to the civil, the military helicopters are developed based on sufficient requiring amount following conversion to the civil helicopters with minor modification. This paper presents the investigation and the analysis for the case and the approach of dual use helicopter development from military helicopters to civil helicopters.

• The KSFM Journal of Fluid Machinery
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• v.15 no.5
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• pp.20-26
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• 2012

An APU(Auxiliary Power Unit) for helicopters has been developed in Korea and tested at the AETF(altitude engine test facility) in KARI(Korea Aerospace Research Institute) for the purpose of the military qualification. A cell correlation test was performed before the official test, and the results are within the tolerance. The APU has the capability of supplying electric power as well as compressed air to the helicopters. It was tested at bleed extraction conditions, electric power extraction conditions, and maximum continuous concurrent power conditions within the entire helicopter flight envelop. Some special test equipments were implemented for the measurement of air flowrate, electric power and so on. The tests were successfully performed and their results satisfy the requirements of the helicopters.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.12 s.105
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• pp.1327-1331
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• 2005

This Paper addresses what amount of whole-body vibration is exposed to Korean pilots of UH60 helicopters during their mission flight. To measure the expose4 whole-body vibration, the 12-axis whole-body vibration measurement system was used. It enables the direct measurement of whole-body vibration exposed from the body contact area consisting of the feet, hip and back. The measured 12-axis vibration signals were used to evaluate the vibration comfort level experienced by the pilots of UH60 helicopters. The evaluated vibration comfort level is found to be closeto 0.74-0.79m/s, which is equivalent to the semantic scale of 'fairly uncomfortable'. To assess the health effects of whole-body vibration exposed to Korean pilots of UH60 helicopters during their mission flight, the rms-based and VDV(vibration dose value)-based evaluation schemes, recommended by ISO 2631-1:1977, were exploited in this work. The evaluated results indicate that Korean pilots cannot avoid the fatigue-decreased proficiency limit after two-hour continuous flight. The whole-body vibration level exposed from the UH60 helicopters during continuous 10-hours mission flight is found to reach to the vibration exposure limit.

• The KIPS Transactions:PartA
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• v.14A no.5
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• pp.255-262
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• 2007

Physically-based researches on simulating helicopter motions have been achieved in the field of aeronautics, aerodynamics and others. These results, however, have not been appled in the computer graphics area, mainly due to their complex equations and heavy computations. In this paper, we propose a dynamics model of helicopter rotor blades, which would be easy to implement, and suitable for real-time simulations of helicopters in the computer graphics area. Helicopters fly by the forces due to the collisions between air and rotor blades. These forces can be interpreted as the impulsive forces between the fluid and the rigid body. Based on these impulsive forces, we propose an approximated dynamics model of rotor blades, and it enables us to simulate the helicopter motions using existing rigid body simulation methods. We compute forces due to the movement of rotor blades according to the Newton's method, to achieve its real-time computations. Our prototype implementation shows real-time aerial navigation of helicopters, which are murk similar to the realistic motions.

• Journal of the Korea Society for Simulation
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• v.12 no.1
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• pp.73-83
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• 2003

This paper presents armed vehicle BAttle Group Simulation model(called BAGSim) which is an object-oriented simulation system for representing battle group engagement consisting of tanks and helicopters. BAGSim is designed in the evolutionary software life cycle approach with the Unified Software Development Process, and implemented with C++ language. BAGSim consists of a preprocessor for engagement scenario definition and simulation data set up, a main processor for triggering engagement event and advancing simulation clock, and a post processor to record simulation histories. Application scenario covers several type of engagement among command tanks, fight tanks, scout helicopters, attack helicopters, anti-tank guided missiles, and decoys. Thus, BAGSim can be effectively used as an analytic tool to examine some operational concepts and tactics, further experimentally fine tune tank design options.

• 시스템엔지니어링워크숍
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• s.4
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• pp.146-150
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• 2004

The Tactical Data Link System(TDLS) is a standardized communication link to exchange and interface positional, situational information, command and control in real time. It has been evaluated that the link would play an important role for tactical interoperability, situation awareness, and execution of joint operations in the future war. This work presents how to embody the TDLS through the systems engineering approach on the base of TDLS operating concept analysis of helicopters-groud units.

• Journal of the military operations research society of Korea
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• v.28 no.2
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• pp.125-136
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• 2002

This paper is aimed to develop Tank Simulation Model. The model simulates Tank-to-Tank engagement and Tank-to-Helicopter engagement by considering Korean battlefield environment. The simulated entities are command tanks, fight tanks, scout helicopters, attack helicopters, anti-tank guided missiles, and decoys. In this paper, we explain the model operational concept, model development and finally we will show some illustrative examples.

• Journal of Internet Computing and Services
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• v.10 no.3
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• pp.35-49
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• 2009

In electronic warfare settings, battlefield helicopters identify various threats based upon threat data, which are acquired using their multi-sensors of aircraft survivability equipment (ASE). To continually function despite of potential threats and successfully execute their missions, the battlefield helicopters have to repeatedly report threats in simulated battlefield situations. Toward this ends, the paper presents threat unification using multi-sensor simulator and its implementation. The simulator consists of (1) threat attributes generator, which models threats against battlefield helicopters and defines their specific attributes, (2) threat data generator, which generates threats, being similar to real ones, using normal, uniform, and exponential distributions, and (3) graphic display for threat analysis and unification, which shows unified threat information, for example, threat angle and its level. We implement a multi-sensor threat simulator that can be repeatedly operable in various simulated battlefield settings. Further, we report experimental results that, in addition to tangibly modeling the threats to battlefield helicopters, test the capabilities of threat unification using our simulator.

• Current Research on Agriculture and Life Sciences
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• v.32 no.3
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• pp.159-163
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• 2014

Agricultural unmanned helicopters have become a new paradigm for aerial application. Yet, such agricultural helicopters require easy and affordable attitude control systems. Therefore, this study presents an affordable attitude measurement system using a DCM (direction cosine matrix) algorithm that would be applied to agricultural unmanned helicopters. An IMU using a low-cost MEMS and an algorithm to estimate the attitude of the helicopter were applied in a gimbals structure to evaluate the accuracy of the attitude measurements. The estimation errors in the attitude were determined in comparison with the true angles determined by absolute position encoders. The DCM algorithm and sensors showed an accuracy of about 1.1% for the roll and pitch angle estimation. However, the accuracy of the yaw angle estimation at 3.7% was relatively larger. Such errors may be due to the magnetic field of the stepping motor and encoder system. Notwithstanding, since the intrinsic behavior of the agricultural helicopter remains steady, the determination of attitude would be reliable and practical.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.132-137
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• 2005

This paper addresses what amount of whole-body vibration is exposed to pilots of UH60 helicopters during flight. To measure the whole-body exposed from the feet and seat, the 12-axis vibration measurement system was used. It enables simultaneous measurement of vibration exposure from the body contact area of the feet, hip and back. The measured 12-axis vibration signals are exploited to the comfort level of UH60 helicopters during flight. It is shown that the evaluated ride value is close to $0.74{\sim}0.79m/s^2$ and that it is equivalent to the semantic scale of 'fairly uncomfortable'. To assess the health effects of whole-body vibration exposed to pilots of UH60 helicopters during their flight, the rms-based and VDV(vibration dose value)-based evaluation results of measured four-axis vibration signals are shown in this work. The fatigue-decreased proficiency limit, whose level is half of the exposure limit, is expected to come after the two-hour flight. The exposure limit is shown to reach after the 10-hour flight.