Aerodynamic Drag Effects of Externally Mounted LiDAR on Vehicles

With the development of autonomous driving technology, onboard sensor systems have gradually become an essential component of intelligent vehicles. However, externally mounted sensors, particularly Light Detection and Ranging (LiDAR) systems, can alter the original aerodynamic geometry of a vehicle. This can potentially cause flow separation, wake enhancement and increased aerodynamic drag. Then, energy efficiency and driving range will be affected. This paper focuses on the influence of LiDAR on the aerodynamic performance of autonomous vehicles. First, the basic working principles and major types of LiDAR, including mechanical spinning and solid-state LiDAR, are introduced. Also, their importance in environmental perception for autonomous driving is discussed. Subsequently, based on the theory of aerodynamic drag, the effects of LiDAR installed at different locations(such as the roof, front, side, and rear of the vehicle)on the external flow field, pressure distribution, and wake structure are analysed. Furthermore, the main approaches for reducing the aerodynamic impact of LiDAR are summarised, such as sensor shape optimisation, low-profile design and streamlined structural design. In the future, with the development of solid-state LiDAR and intelligent optimisation technologies, sensors are expected to become increasingly compact, integrated and collaboratively optimised. It will enable a better balance between environmental perception performance and vehicle aerodynamic efficiency.