후륜 조향과 미끄럼 조향 시스템을 가진 세 바퀴 자동차의 조종 안정성 및 전복 안정성 제어

Abstract

It is expected that personal urban electric vehicles will be used in the future because of regulations on carbon dioxide emission, rising energy demands and high oil price. With change of a number of wheels and various steering systems, alternative chassis structures can be used for the personal urban electric vehicle. In previous research, the three-wheeled vehicle with two motorized front wheel for torque distribution and steer-able single rear wheel was suggested for the alternative chassis structure of the personal urban electric vehicle, Proposed three-wheeled vehicle has different dynamic characteristics from four-wheeled conventional vehicle, due to different steering system and the number of wheels. Because the number of wheels is changed, three-wheeled vehicle has larger load transfer and worse rollover stability. Also, the vehicle path, lateral ac-celeration, and vehicle attitude are different, because of rear wheel steering and different position of mass center. If a driver feels the differences in handling and ride during the driving, the driver may feel uncomfort-able. Therefore, it is necessary to control to reduce the differences of car performance between conventional four-wheeled vehicle and the three-wheeled vehicle. Rollover stability control which guarantees driver`s safety should be conducted in three-wheeled vehicle because of its structural limitation in preventing rollover passively. The goal of this research is to suggest solutions for these problems. This study consists of two parts. First part is comparison of vehicle dynamic characteristics between conventional vehicle and proposed three-wheeled vehicle. Second part is research of control for handling and rollover stability. The handling control is to reduce differences of dynamic characteristics of vehicle, when driver inputs same steering angle and diving torque. Using reference model with four-wheeled conventional configuration, three-wheeled vehicle is controlled to follow the m