Professor Sang Joon Shin, from the Department of Aerospace Engineering, leads the Multi-Discipline Integrated Urban Air Mobility Core Technology Development Center (ERC Center). This center focuses on the development of seven core technologies: vertical take-off and landing (VTOL), long-range flight, distributed electric propulsion (DEP), motor drive/hybrid, autonomous flight, sensor, and noise reduction. The ERC center is to establish fundamental research capabilities in this field and develop expertise in design, analysis, and production, thereby reducing reliance on foreign commercial software.

The development of Urban Air Mobility (UAM) has gained significant momentum since the release of the Uber Elevate white paper in 2016, with the primary goal of alleviating urban traffic congestion. Electric VTOL (eVTOL) vehicles have become a prominent focus due to their potential to meet UAM’s key requirements, such as low noise, VTOL capability, and quick turnaround times.^[2] However, for these vehicles to reach their full potential, seamless infrastructure integration is essential. Given the unique characteristics of VTOL aircraft and their flight envelope, the construction of new facilities, referred to as “Vertiports,” will be imperative to accommodate these aircrafts. Additionally, a comprehensive overhaul of the air traffic control system, including technical and regulatory aspects, will be necessary. The combination of these formidable challenges underscores the complex and multidisciplinary nature of UAM infrastructure.

Within this ERC center, there are three distinct groups. Group 1 focuses on initial UAM configuration design and development of high-precision analysis methodology. This group aims to determine the initial configuration, including the outer mold line, electric/hybrid propulsion system, and battery management system. This configuration will then be shared with the other groups to proceed to later design phases. In Group 2, a robust flight dynamics control algorithm is under development, and they are building an urban flight environment simulation with a flight controller. Group 3 is working on computational analysis for UAM, particularly regarding impact scenarios and noise level in various flight modes. Recently, the conceptual design phase of the prototype article has been completed, and production is underway.

The Active Aeroelasticity and Rotorcraft Lab (AARL), led by Professor Shin, comprises three groups within the ERC center, focusing on conceptual and structural UAM design. AARL has developed a foundational design framework capable of capturing the key features of various eVTOL configurations. This software, integrated with NASA-developed analysis programs, empowers researchers to obtain comprehensive results encompassing mission performance, weight estimation, and parametric studies.^[2] Researchers have used this software to explore key trade-off relationships within each aircraft configuration. For instance, the software has been utilized in assessing and optimizing important geometric parameters for a tiltwing-type vehicle within the general UAM mission profile.^[2] Not limited to the tiltwing type vehicle, the software has also facilitated the initial conceptual design of three other representative eVTOL configurations, enabling their subsequent development and facilitating insightful comparisons among these vehicles.

Among these representative eVTOL configurations, AARL has conducted structural design for a lift+cruise (LPC) type vehicle. While a significant portion of aircraft design process relies on empirical trend formulas, the new concept of UAM has prompted AARL to develop new methodologies for designing such innovative vehicles. One methodology adopts the results of topology optimization in constructing the fuselage frame, while the other methodology explores the design space by simplifying geometric characteristics to expedite the design process. Both methodologies don’t require an extensive dataset to establish trend formula and are applicable to general configuration with feasibility. In addition, AARL has investigated the structural behavior of an LPC vehicle through static structural and modal analysis, particularly concerning the battery locations.

Professor Shin is actively working on integrating the multidisciplinary research findings from the ERC center to advance the UAM market in Korea to the next level. Expanding the scope of preliminary design to encompass other configurations and further developing core technologies will provide valuable insights into the field of UAM.

References

1. Cha, W. S., Park, S. H., Hwang, M. H., Chang, Y. H., Ahn, C. H., and Shin, S. J., “Design of a Lift+Cruise eVTOL Aircraft reflecting the Geometry and Structural Details regarding Battery Locations,” Proceedings of the Vertical Flight Society’s 79th Annual Forum and Technology Display, 2023.

2. Chang, Y. H., Park, S. H., Kim, Y. J., Ahn, C. H., Cha, W. S., Hwang, M. H., and Shin, S. J., “Advanced Optimization Framework of a Tiltwing eVTOL Aircraft including Geometry Consideration,” 2023 Autonomous VTOL Technical Meeting and Electric VTOL Symposium, 2023.