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This paper deals with a combustion control system design problem for premixed diesel engines. Premixed diesel combustions can achieve high thermal efficiency while reducing emissions. However, premixed diesel combustions have low robustness with respect to changes in the environment. The traditional engine control is the feedforward control using look-up table called control map. Therefore, it is difficult to maintain a stable combustion for the premixed diesel combustions. Moreover, making the control map requires a huge number of experiments. In this paper, in order to robustly realize the premixed diesel combustion, a passivity-based adaptive output feedback control system design scheme is proposed based on a discrete dynamics model of the diesel combustion. The proposed method controls the in-cylinder heat release rate at each combustion cycle.

Vehicle lateral states such as lateral distance at a preview point and heading angle are indispensable for lane keeping control systems, and such states are normally estimated by fusing signals from an onboard vision system and inertial sensors. However, the sampling rates and measurement delays are different between the two kinds of sensing devices. Most of the conventional methods simply neglect measurement delay and reduce sampling rate of the estimator to adapt to the slow sensors/devices. However, the estimation accuracy is deteriorated, especially considering the delay of visual signals may not be constant. In case of electric vehicles, the actuators for steering and traction are motors that have high control frequency. Therefore, the frequency of vehicle state feedback may not match the control frequency if the estimator is infrequently updated. In this paper, a multi-rate estimation algorithm based on Kalman filter is proposed to provide lateral states with high frequency.

In this paper, the range extension control system based on least square method is proposed for electric vehicles with in-wheel motors and front active steering. This proposed method distributes front and rear wheel side-slip angles and driving force difference between left and right motors from lateral force and yaw-moment. The proposed method enables to reduce driving resistance generated from front steering angle. In fact, the mileage per charge is extended up to 200 m/kWh. Simulations and experiments are carried out to confirm the effectiveness of the proposed method.

Biomass is one of the attractive alternative fuels, which exists dispersively. Small size gas engine power generation with gasification biomass gas is one of the efficient methods. However, since its calorific value is lower and its composition can be affected by gasifying conditions, it is difficult to stabilize and achieve high thermal efficiency engine operation. This study aims to develop a small size gas engine system with biomass gas by modifying the control system of a conventional spark ignition engine. In this paper, effect of fuel composition on combustion was clarified experimentally to get guideline for the engine control system.

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.

In this paper, longitudinal automated vehicle control for platooning is investigated by both experiment and simulation. Two-car platooning is realized by controlling the throttle of the following car. A vehicle model which is used for simulation and as a control model for experiment is constructed. The model contains nonlinear elements of the engine, the torque converter and the automatic transmission. Comparison of sliding control(SC) and PID control(PID) is done under various conditions. It is shown that especially under large initial deviation from the target state sliding control has better stability and more rapid convergence than PID control.