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This paper describes a novel catalytic oxidation sensor which represents an attempt to realise a practical sensor for on vehicle detection of catalyst efficiency and misfire. Via experimental and modelling approaches, promising characteristics are established, which could mean that an application to the on-vehicle detection of catalyst efficiency and misfire is feasible.

Afterburning of a rich exhaust/air mixture ahead of the catalyst has been shown in earlier papers to offer an effective means of achieving catalyst light-off in very short times. Protection of the catalyst from overheating is an important aspect of systems using EGI, and on board diagnostics will be required to check for proper function of EGI. In this paper, some options for these requirements are discussed, using a high temperature linear thermistor.

A novel control method based on full-order sliding mode is proposed in this paper to solve the trajectory tracking control problem of unmanned vehicle formation. The complexity of the unmanned vehicle system is considered and a dynamic error model of the system is established . A full-order sliding mode control method is adopted to realize the cooperative control of unmanned vehicle systems. The unmanned vehicle system can force each vehicle accurately track the specified trajectory. The simulation results show that the designed full-order sliding mode control method has excellent performance compared with the traditional linear sliding mode control in terms of accuracy and robustness. In the case of large changes in different types of road surface and vehicle dynamics, the movement of unmanned vehicles is effectively controlled, and the trajectory tracking control of unmanned vehicle formation system is realized.

Recent studies in the USA have revealed that the catalysts (which are universally fitted to gasoline automobiles) are failing in service to an unacceptable extent. Although the reasons for the failures are not completely clear, it seems that misfiring, leading to highly exothermic reaction in the catalyst, may be responsible for the damage. Legislation is to be enacted later in this decade to address this problem by requiring on board diagnostic (OBD) systems which can measure misfire, as well as catalyst hydrocarbon (HC) conversion efficiency. Although some ideas have been suggested for the OBD requirements, no fully satisfactory sensor technology has yet appeared. This paper describes a novel hydrocarbon sensor based on a surface catalysis principle. The fundamental studies reported here have been made with the automobile application in mind. A catalytic chemi-ionisation model is proposed in order to enhance our understanding of this surface ionisation.