This book describes the design and implementation of an advanced driver-assistance system for personal transporters (PTs) using the concept of personal space (PS), which is the space in which invasion by others induces a psychological strain. The study first investigated a microscopic simulation model of a PT encountering pedestrian flows and evaluated the effects of the proposed assistance system using evaluation indexes including invasion ratio and crossing time. Then, a prototype of a four-wheeled PT equipped with an advanced driver-assistance system was developed. Simulation results suggest that the average invasion ratio increased with increasing density of pedestrians. This increase was confirmed by experiments in which pedestrians felt increasing levels of discomfort and fear toward the PT when the pedestrian density increased. Moreover, the effectiveness of the assistance system was confirmed in numerical simulation and experiments. The present findings have proved a potential application of PMVs considering the psychological factor of pedestrians to achieve a sustainable transport system.