A Novel Mechanism and Method of Vehicle Wheelbase Measurement Based on LiDARs

Vehicle wheelbase has a significant impact on the stability and maneuverability of a vehicle, and the current wheelbase measurement method is mainly contact based. To address the need for noncontact and rapid wheelbase measurement, a wheelbase measurement method based on linear light detection and ranging (LiDAR) is proposed. First, a sensor setup for surface scanning of the vehicle tire area is developed by combining two stepper motors and two linear LiDARs, enabling the acquisition of point clouds from the tire area. Subsequently, during the point cloud filtering phase, a window-based plane partition fitting strategy is introduced for ground filtering, which can more accurately and comprehensively fit the ground and perform filtering. To further enhance the efficiency of the measurement method, the single-region growth (SRG) is proposed for extracting point clouds within the tire area. Finally, a rapid tire annulus detection method based on directional gradient is developed to accurately locate the tire center. The wheelbase is subsequently calculated using the front and rear tire centers. Comparing with other vehicle wheelbase measurement methods, the experimental results indicate that the proposed method is applicable to various vehicle types and achieves an average measurement error of less than 0.8%, thus meeting industry precision requirements.