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More than three-fourths of the unburned hydrocarbon (HC) emissions in a typical drive cycle of an automotive engine are produced in the initial 2 minutes of operation, commonly known as the coldstart period. Catalyst light-off plays a very important role in reducing these emissions. Model-based paradigm is used to develop a control-oriented, thermodynamics based simple catalyst model for coldstart purposes. It is a modified version of an available model consisting of thermal dynamics and static efficiency maps, the critical modification being in the thermal sub-model. Oxygen storage phenomenon does not play a significant role during the warm-up of the engine. The catalyst is modeled as a second-order system consisting of catalyst brick temperature and temperature of the feedgas flowing through the catalyst as its states. Energy balance of an unsteady flow through a control volume is used to model the feedgas temperature, whereas energy balance of a closed system is used to model the catalyst brick temperature. Wiebe profiles are adopted to empirically model the HC emissions conversion properties of the catalyst as a function of the catalyst temperature and the air-fuel ratio. The static efficiency maps are further extended to include the effects of spatial velocity of the feedgas. Experimental results indicate good agreement with the model estimates for the catalyst warm-up. It is shown that the model represents the system more accurately as compared to the previous model on which it is based and offers a broader scope for analysis.

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Test and verification procedures are a vital aspect of the development process for embedded control systems in the automotive domain. Formal requirements can be used in automated procedures to check whether simulation or experimental results adhere to design specifications and even to perform automatic test and formal verification of design models; however, developing formal requirements typically requires significant investment of time and effort for control software designers. We propose Signal Template Library (ST-Lib), a uniform modeling language to encapsulate a number of useful signal patterns in a formal requirement language with the goal of facilitating requirement formulation for automotive control applications. ST-Lib consists of basic modules known as signal templates. Informally, these specify a characteristic signal shape and provide numerical parameters to tune the shape. We propose two use-cases for ST-Lib: (1) allowing designers to classify design behaviors based on user-defined numerical parameters for signal templates, and (2) automatic identification of worst-case values for the signal template parameters for a given closed-loop model of an embedded control system. We show how ST-Lib can be used to improve user productivity by demonstrating its effectiveness on two case studies.

In the past decade robotics and the Internet, fed by the great advances in computing and networking, matured into giant interdisciplinary scientific fields. Therefore, it is not surprising that many are trying to merge these two technologies and develop Internet-based robotic teleoperation. More interestingly, Internet-based bilateral teleoperation, where supermedia is fed back to the operator in order to increase efficiency and achieve telepresence. Supermedia is the collection of multimedia (video, audio, ...), haptic and other sensory information. This paper studies supermedia enhanced teleoperation via the Internet, concentrating on the real-time control of such systems and their performance. The potential of this technology and its advantages will be explored. In addition, key issues, such as stability, synchronization and transparency, will be analyzed and studied. Specifically, event-based planning and control of Internet-based teleoperation systems is presented with experimental results of several implemented system scenarios.