The segment of micro-vehicles has experienced an increasing spread in recent
years since its positive implications for both individual road users and the
whole urban scenario. An experimental and numerical analysis on a standing
electric scooter (e-scooter) is proposed with the aim of evaluating the
longitudinal performance and the influence of rider positioning on the dynamics
of the whole system; for this purpose, an e-scooter available in Europe and at
mid-range price is considered. The vehicle is instrumented to monitor its
longitudinal position, velocity, and acceleration. Test procedure and data
processing are defined to homogeneously acquire and manage the signals. The
experimental campaign is divided into three main categories corresponding to
different maneuvers, i.e., acceleration, braking, and coasting. Specific
attention is given to the electric motor modalities, both in driving and
regeneration; moreover, the dependency of the rolling resistance force on tire
inflation pressure is investigated. Braking maneuvers are performed on different
surfaces and with different drivers.
A three degrees of freedom (3-DOF) lumped parameter model is developed in
Matlab/Simulink and validated using the experimental results where the DOFs are
the translational motion of the entire system and the rotations of the front and
rear wheels; a fourth DOF is then added, separating the rider and vehicle
masses, to better fit the real dynamic behavior and the experimental evidence.
Finally, the effects of rider features related to his anthropometry and driving
experience are assessed in severe braking maneuvers.
