• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제48권9호
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• pp.691-701
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• 2020

An actuator mixer design using convex optimization technique situation where the propulsion system of an electric VTOL UAV during vertical take-off and landing maneuvers is proposed. The attainable control set to analyze the impact from failure of each motor and propeller can be calculated and illustrated using the properties of the convex function. The control allocation can be defined as a convex function optimization problem to obtain an optimal solution in real time. The mixer is implemented using a convex optimization solver, and the performance of the control allocation methods is compared to the attainable control set. Finally, the proposed mixer is compared with other techniques with nonlinear sux degree-of-freedom simulation.

• Journal of Advanced Navigation Technology
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• 제23권4호
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• pp.265-272
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• 2019

In this paper, we selected commuting scenarios in the most congested metropolitan area in Korea, and conducted noise analysis during personal air vehicle (PAV) operation using aviation environmental design tool (AEDT)software which was developed by Federal Aviation Administration (FAA). Noise is the second important factor after safety in order to operate PAVs through concepts such as ODM (on-demand mobility) introduced by National Aeronautics and Space Administration (NASA). Noise analysis were performed by modeling low-noise ePAVs as commercial helicopters and predicted residential suitability in order to resolve problems in which accurate NPD (noise power distance) data from PAVs were not released. The application of noise reduction technology such as electric propulsion has significantly reduced noise exposure levels and has reached the conclusion that commuting with PAVs is feasible without noise problems in the metropolitan area.

• Journal of Advanced Navigation Technology
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• 제28권4호
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• pp.436-441
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• 2024

Urban air mobility (UAM) is an innovative air traffic management system that utilizes electric vertical take off and landing aircraft(eVTOL) to transport passengers and cargo in urban areas. The corridor can be defined as the airspace that the vehicle operates in and must be collaboratively managed. For the stable operation of UAM, it is essential to have strategic separation and a collaborative decision-making(CDM) system for cooperation and coordination among stakeholders. This study examines the application of time-based milestones from traditional air traffic flow management to the UAM system to ensure safe traffic volume and optimize air traffic flow. For traffic flow management, the milestone time information is categorized into a total of 13 key milestone time indicators based on the UAM movement status, and the sharing entities providing each time indicator and the flow of milestones are defined. Emphasizing the need for a CDM to balance UAM traffic and capacity, sharing and managing milestone information among stakeholders is expected to improve UAM aircraft departure flow and enhance operational efficiency.

• Journal of Advanced Navigation Technology
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• 제28권3호
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• pp.300-308
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• 2024

Urban air mobility (UAM) is emerging as a revolutionary transportation solution to urban congestion and environmental issues. Especially, electric vertical take-off and landing (eVTOL) aircraft are expected to enhance urban mobility, reduce traffic congestion, and decrease environmental pollution. However, the successful implementation and operation of UAM systems heavily rely on advanced technological infrastructure, particularly in sensor technology. Among these, 3D light detection and ranging (LiDAR) systems are essential for detecting obstacles and generating pathways in complex urban environments. This paper focuses on the challenges of developing LiDAR-based perception solutions, emphasizing the importance and performance of object detection capabilities using 3D LiDAR. It integrates LiDAR data processing algorithms and object detection methodologies to experimentally validate the effectiveness of perception solutions that contribute to the safe navigation of aircraft. This research significantly enhances the ability of aircraft to recognize and avoid obstacles effectively within urban settings.

• Journal of Advanced Navigation Technology
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• 제28권4호
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• pp.393-399
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• 2024

The digital map computer for advanced air vehicles (AAV) must be high-performance, lightweight, portable, and modular. It should receive data on terrain, weather, and obstacles from external modules to display digital maps accurately. This necessitates robust communication capabilities with external devices via an Ethernet interface and the ability to output digital map visuals clearly through an high-defintion multimedia Interface (HDMI) or digital visual interface (DVI) interface. This paper presents the design of both hardware and software architecture that fulfills these critical requirements for an AAV digital map system. Additionally, it establishes the minimum specifications needed and verifies the suitability of the designed digital map computer through rigorous performance measurements and testing. By ensuring these standards, the digital map computer can reliably support the complex navigational needs of AAV, enhancing operational efficiency and safety.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제49권3호
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• pp.233-241
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• 2021

As increasing the feasibility of the eVTOL UAM(electric vertical take-off and landing urban air mobility), numerous corporations and laboratories are conducting researches. In the aircraft development process, estimating the cost of the aircraft is essential part in terms of budgeting and commercial viability analysis. However, it is difficult to predict the cost of an eVTOL UAM owing to various configurations and little open cost information. This paper presents a novel method to predict the vehicle cost of various eVTOL configurations by modifying previous studies of the aircraft cost estimation. A vehicle cost of Wisk Cora is calculated by the presented method as an example to illuminate the method. The method is indirectly validated by comparing the vehicle costs of six representative eVTOL aircraft with those from the UAM study reports.

• Journal of Advanced Navigation Technology
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• 제28권3호
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• pp.288-299
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• 2024

Indonesia's Keplauan Liau region is facing limitations in the development of connected transportation infrastructure due to its archipelago nature, budget constraints, and lack of land. Transportation demand is increasing due to its strategic location in the Malacca Strait Business Triangle and many tourist visits from Singapore and Malaysia. However, due to the nature of connecting many islands, the establishment of transportation infrastructure has not been achieved. This paper aims to predict the innovations that can be brought about by the introduction of advanced air mobility (AAM) with an electric vertical take-off and landing (e-VTOL) system through analysis and application consideration of the actual situation in Indonesia's Kepulauan Liau region. In addition, it intends to contribute to national-level review and policy establishment on the establishment of innovative transportation infrastructure using AAM, reflection in infrastructure construction plans, and active global cooperation.

• Journal of Advanced Navigation Technology
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• 제25권1호
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• pp.29-39
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• 2021

As a means of solving traffic congestion in the downtown of large city, the interest in urban air mobility (UAM) using electric vertical take-off landing personal aerial vehicle (eVTOL PAV) is increasing. eVTOL configurations that will be used for UAM are classified by lift-and-cruise, tilt rotors, tilt-wings, tilted-ducted fans, multicopters, depending on propulsion types. This study tries to perform preliminary conceptual design for a given mission profile using reverse engineering techniques by taking the multicopter type Airbus's CityAirbus as a basic model. Wetted area, lift to drag ratio, drag coefficients were calculated using the OpenVSP which is an aerodynamic analysis software. The power required for each mission section of CityAirbus were calculated, and the corresponding battery and motor were selected. Also, total weight was predicted by estimating component weights of eVTOL.