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With increasingly stringent emission requirement in China the evaporative emission legislation for motorcycles has been issued since July of 2008. According to the vehicle investigation two type effective solutions for EFI engine can be optional for this requirement: Passive system (not controlled by EMS) and active system (controlled by EMS). For passive system how to ensure enough purge flow but minimize the influence on mixture formation is the key and for active type, the point will focus on how to control and calculate the exact purge flow amount with the fluctuated intake air pressure for single cylinder engine. In this paper the strategy for both purge flow control solutions has been presented especially for single cylinder motorcycle engine.

In electric fuel injection (EFI) systems the intake air pressure is used as system load signal for calculating injection and ignition parameters together with engine speed. Part of an EFI system for motorcycles is a throttle body module with integrated pressure sensor. As motorcycle systems require smaller components than automotive applications the target for engineering is to minimize the component size and still fulfill other system requirements. Therefore the pressure sensor sampling point should be as close as possible to the throttle shaft to reduce the module size but with a sufficient distance to avoid signal distortion by unsteady flow. This paper describes how to find a suitable sampling position by combining static bench testing, dynamic vehicle testing and CFD analysis.

Engine management systems (EMS) for small engines require some specific solutions that are different from EMS for automotive engines. The specific requirements are due to special behavior of these engines on one hand, and the need for cost saving by reduction of the number of components on the other hand. Some special functions for small engines are introduced: engine load detection for P-n system, ambient pressure detection, stroke detection and anti reverse rotation function. In single cylinder engines, the intake air pressure and engine speed signal fluctuate periodically. At first, the special behavior of these two signals is investigated for different working conditions. Then functions for load detection and ambient pressure estimation are designed based on intake air pressure signal, and functions for stroke detection and anti-reverse are developed on the basis of engine speed detection. Test results show that these functions work well.

Bosch/UAES has developed a low cost EMS special for small gasoline engines. The article will introduce this system from view of components design and system design. In components design part special component design for small gasoline engine to reduce cost is described. To reduce cost a special low end ECU and fuel deliver system has been designed, other low-end components are chosen into the system. Features of the components are described. In system design part the requirement of system design is described. To reduce cost normal components configuration should be redesigned. Special design and consideration of load detection, engine speed detection, system components configuration and optional solutions is expressed. For load detection, both P-system and alpha/n system is introduced. For engine speed detection both segment and increment system is introduced. System components configuration for low cost EMS is introduced and feasibility is explained.

A flat neural network is designed for the on-line state prediction of engine. To reduce the computational cost of weight matrix, a fast recursive algorithm is derived according to the pseudoinverse formula of a partition matrix. Furthermore, the forgetting factor approach is introduced to improve predictive accuracy and robustness of the model. The experiment results indicate that the improved neural network is of good accuracy and strong robustness in prediction, and can apply for the on-line prediction of nonlinear multi input multi output systems like vehicle engines.

In this paper, an investigation is made to the friction clutch engagement control of automotive AMT systems based on a nonlinear dynamic model with double inputs. According to friction torque transmission characteristics during clutch engagement, an equivalent, fully controllable and linearized model and the feedback linearization control are derived from the original system with nonlinearities via homomorphic transforms. By the resulting mathematical modeling, computer simulations are made both for the original nonlinear and feedback linearized systems with incorporation of ordinary PID controllers to follow ideal vehicle dynamic responses. It has been shown by comparison between the two sets of numerical results that the feedback linearization control designed for the nonlinear system is of fine accuracy and robustness in model tracking behaviors of clutch engagements.