Urban Air Mobility (UAM) is emerging as a transformative solution to urban traffic congestion and inefficient ground travel. This paper presents the UAM development of Shenzhen, a pioneering city of low-altitude economy in China. It focuses on eVTOL drones for Shenzhen UAM, systematically reviewing the technical challenges, policy support, and practical progress. Firstly, the technical status of eVTOL drone design and research is reviewed, and the multidimensional technologies and application bottlenecks faced by eVTOL drones are identified. Secondly, by combining flight safety technology and urban air mobility regulation technology, the systematic technical challenges of urban low-altitude traffic based on eVTOL drones are analyzed. Furthermore, from the perspective of coordinated promotion of infrastructure and regulation, the foundation of urban air mobility applications is clarified, among which efficient flight approval and large-scale construction of takeoff and landing sites across the entire city represent prominent advantages of Shenzhen’s future air mobility. Then, given the high correlation between the systemic technological challenges of urban air mobility and low-altitude economic policies, this paper reveals the complementary relationship between technological challenges and low-altitude policies based on the current status of Shenzhen’s policy promotion and its impact on technology and industry. Finally, the technical issues and regulatory trends faced by eVTOL drones in urban air mobility in Shenzhen are summarized, and combined with the global and Chinese commercial prospects of manned eVTOL drones, suggestions for the future development of urban air mobility in Shenzhen are proposed from the following four dimensions: technology research and development, infrastructure, industrial ecology, and regional coordination.

An aerodynamic/hydrodynamic investigation of water cross-over is performed for a bionic unmanned aquatic–aerial amphibious vehicle (bionic UAAV). According to flying fish features and UAAV flight requirements of water cross-over, the bionic conceptual design of crossing over water is described and planned in multiple stages and modes of motion. A solution procedure for the numerical simulation method, based on a modified SST turbulence model and the VOF model, is expressed, and a verification study is presented using a typical case. Longitudinal–lateral numerical simulation analysis investigates the cruise performance underwater and in the air. The numerical simulation and principal experiment verification are conducted for crossing over water and water surface acceleration. The results indicate that the bionic UAAV has an excellent aerodynamic/hydrodynamic performance and variant configuration to adapt to water cross-over. The bionic UAAV has good water and air navigation stability, and the cruise flying lift–drag ratio is greater than 15 at a low Reynolds number. Its pitching moment has the phenomenon of a “water mound” forming and breaking at the water cross-over process. The present method and the bionic variant configuration provide a feasible water cross-over design and analysis strategy for bionic UAAVs.

Aerodynamic investigation of a bionic coaxial-rotors unmanned aerial vehicle (UAV) is performed. According to Chinese parasol seed features and flight requirements, the bionic conceptual design of a coaxial-rotors UAV is described. A solution procedure for the numerical simulation method, based on a multi-reference frame (MRF) model, is expressed, and a verification study is presented using the typical case. The aerodynamic design is conducted for airfoil, blade, and coaxial-rotors interference. The aerodynamic performance of the coaxial rotors is investigated by numerical simulation analysis. The rotor/motor integrated experiment verification is conducted to assess the performance of the coaxial-rotors UAV. The results indicate that the UAV has excellent aerodynamic performance and bionic configuration, allowing it to adapt to task requirements. The bionic UAV has a good cruise power load reach of 8.36 kg/kw, and the cruise flying thrust force is not less than 78 N at coaxial-rotor and rotor-balloon distance ratios of 0.39 and 1.12, respectively. It has the “blocks stability phenomenon” formed by the rotor downwash speed decreases and the balloon’s additional negative pressure. The present method and the bionic configuration provide a feasible design and analysis strategy for coaxial-rotors UAVs.

This paper presents a fuel saving double channel wing (FADCW) configuration for a propeller driven aircraft to reduce fuel consumption. In pursuit of this objective, FADCW configuration combines the tractor propeller layout and over-the-wing propeller layout. The basic idea is to improve the wing lift-to-drag ratio by taking advantage of the beneficial propeller influence on the wing. Based on a multi reference frame method solving Reynolds averaged Navier-Stokes equations, the contrastive study of this configuration and a traditional tractor propeller-wing layout is conducted. It is shown that the propeller slipstream in the tractor propeller configuration leads to a 10.28% reduction in the wing lift-to-drag ratio. With the same reference wing area and the propeller rotation speed; however, the FADCW configuration can reduce the wing drag by 10.41% and increase its lift-to-drag ratio by 13.29%, which results in a 20.15% reduction in the fuel consumption compared with the traditional tractor propeller configuration.

A multi-bump strategy combines automatic optimization and flow control and is employed in airframe/intake–exhaust integration design of flying wing. The numerical simulation method of $\gamma -{\overline{\mathrm{Re}}}_{\theta t}$ transition model is verified and used for optimization and validated analysis. According to flow features of basic integration configuration, the multi-bump strategy is proposed. Based on the strategy, the optimization framework is constructed and applied to the design. The research results show that the present method has good design effectiveness. The cruise lift-drag ratio improves 4.1% and longitudinal static stability increases 1.1% at large attack angle. The multi-bump strategy is a skillfully deflected means to improve aerodynamic performance.

Multimodal object detection leveraging RGB and infrared imagery has become essential for robust all-weather perception in unmanned aerial vehicle (UAV) applications. However, existing methods still struggle with effective cross-modal feature fusion, spatial misalignment between modalities, and scale variation of objects in aerial views. In this paper, we propose CMGFDet, a Cross-Modal Gated Fusion Network with Multi-Receptive Field Aggregation designed for RGB–infrared aerial object detection. Our framework introduces three coordinated modules: (1) a Cross-Modal Feature Fusion Network (CMFFN) that employs a gated attention mechanism to selectively aggregate complementary information from both modalities during encoding; (2) a Global–Local Attention Module (GLAM) that performs hierarchical cross-modal feature alignment by jointly modelling global channel statistics and local spatial correlations in the decoder; and (3) a Multi-Receptive Field Aggregation Network (MRFAN) that captures multi-scale contextual information through parallel depthwise convolutions with diverse kernel sizes. Additionally, we incorporate a deep supervision strategy and a composite loss function to enhance training efficiency. Extensive experiments on four public benchmarks (DroneVehicle, RGBTDronePerson, VEDAI, and VTUAV) show that CMGFDet improves the previous best mAP@0.5 by 1.6%, 2.2%, 1.9%, and 2.2%, respectively. The implementation code will be released upon acceptance to support reproducibility.