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An Automated Manual Transmission (AMT) system, which has achieved both cost reduction and low fuel consumption, has been developed. The AMT system can automatically shift using three independently operated actuators mounted in a conventional manual transmission in accordance with a driver's operation and vehicle conditions. For downsizing, weight and cost reductions, a direct actuation driven by DC motor has been selected. To improve vehicle drivability, secure robustness against ambient temperature change and power supply voltage change and aged deterioration, the development object is to improve position control accuracy for the motor control. To meet this object, an actuator structure optimization and a disturbance observer, which is excellent in response characteristics and robust stability are combined. As a result, a highly efficient and reliable the AMT system has been developed and will be introduced through simulation and experimental results.

Switched Reluctance Motor (SRM) mainly has two advantageous characteristics such as no magnet and simple construction. These characteristics contribute lower cost and higher reliability compared with other motor systems such as brushless permanent magnet motors or induction motors. However, SRM has disadvantages that are its torque ripple and acoustic noise in particularly. Moreover, the resonance frequency mode of a motor system is excited by torque ripple, and drive train vibration is caused. These noise and vibration should be suppressed when the SRM is applied to a traction system for passenger electric vehicle since these characteristics affect vehicle quietness and drivability. In this paper, we describe an approach to suppress drive train vibration and acoustic noise.

Rear steering system can improve vehicle stability using active control of the rear wheel angles. For designing the rear steering system, environmental conditions, performance deterioration due to aging and component variation as a result of manufacturing tolerance under mass production must be taken into consideration. We have applied two-degree-of-freedom (2DOF) feedback control with feedforward control for the motor servo control so that the rear steering actuator can track the target rear steering angle accurately and stably. The control system is designed based upon a nominal mathematical model and its variation range. As a result, the rear steering actuator can be controlled with excellent performance and high reliability. This paper describes the mathematical model construction in the frequency domain and a robust motor servo controller design based on 2DOF feedback control with feedforward control.