Experimental Analysis and Multibody Simulation of Electric Kick Scooter Braking Maneuver

Environmental and mobility policies involving big city centers have recently brought to a global spreading of electric micro-vehicles. Electric kick scooters (e-scooters) are indeed leading this category for popularity since their friendly integration in existing urban mobility systems and vehicle sharing services. The main peculiarities distinguishing e-scooters from other motorized two-wheeled vehicles stand in the small vehicle inertia and the driver’s standing position. Since e-scooters are quite recent, scientific research aiming at improving safety and ride comfort is still in progress. The purpose of this research activity is an experimental and numerical investigation of e-scooter emergency braking maneuvers. To achieve this goal, a commercial vehicle is analyzed. On-road tests are conducted instrumenting both the e-scooter and the rider to monitor vehicle performance and human body kinematics. A multibody model representing the whole system is developed in Matlab/Simscape Multibody. Specific attention is given to the rider model. Viscous-elastic properties are included in the joints to reproduce the rider’s dynamic response during the braking maneuver. The model parameters are identified through an optimization process, matching simulated results with experimental data. Results show that the heavy braking of the electric kick scooter is strictly dependent on the rider dynamics. Moreover, a passive human body model can properly represent the human response in this specific maneuver.