Road vehicles contribute to significant levels of greenhouse gas (GHG) emissions. A potential strategy for improving their aerodynamic efficiency and reducing emissions is through active adaptation of their exterior shapes to the aerodynamic environment. In this study, we present a reduced-scale morphing vehicle prototype capable of actively interacting with the aerodynamic environment to enhance fuel economy. Morphing is accomplished by retrofitting a deformable structure actively actuated by built-in motors. The morphing vehicle prototype is integrated with an optimization algorithm that can autonomously identify the structural shape that minimizes aerodynamic drag. The performance of the morphing vehicle prototype is investigated through an extensive experimental campaign in a large-scale wind tunnel facility. The autonomous optimization algorithm identifies an optimal morphing shape that can elicit an 8.5% reduction in the mean drag force. Our experiments provide a comprehensive dataset that validates the efficiency of shape morphing, demonstrating a clear and consistent decrease in the drag force as the vehicle transitions from a suboptimal to the optimal shape. Insights gained from experiments on scaled-down models provide valuable guidelines for the design of full-size morphing vehicles, which could lead to appreciable energy savings and reductions in GHG emissions. This study highlights the feasibility and benefits of real-time shape morphing under conditions representative of realistic road environments, paving the way for the realization of full-scale morphing vehicles with enhanced aerodynamic efficiency and reduced GHG emissions.

翻译：道路车辆是温室气体（GHG）排放的重要来源。一种潜在的改善其气动效率并减少排放的策略是使其外部形状能根据气动环境进行主动适应。在本研究中，我们提出了一种缩比变形车辆原型，它能够主动与气动环境交互以提高燃油经济性。变形是通过改装一个由内置电机主动驱动的可变形结构来实现的。该变形车辆原型集成了一个优化算法，能够自主识别使气动阻力最小化的结构形状。通过在大尺度风洞设施中进行广泛的实验研究，我们考察了该变形车辆原型的性能。自主优化算法识别出一种最优变形形状，能够使平均阻力降低8.5%。我们的实验提供了一个全面的数据集，验证了形状变形的效率，证明了当车辆从次优形状过渡到最优形状时，阻力呈现清晰且一致的下降。从缩比模型实验中获得的见解为全尺寸变形车辆的设计提供了宝贵的指导，这可能带来显著的节能和温室气体减排。本研究强调了在代表真实道路环境的条件下进行实时形状变形的可行性和益处，为实现具有增强气动效率和降低温室气体排放的全尺寸变形车辆铺平了道路。