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Resolvers as position and speed sensors are widely used in many areas including the automotive industry, especially in the application of an electric drive for a hybrid electric vehicle. One of the disadvantages of using resolvers is that their complexity usually leads to quality issues during development that requires engineering resources and time to solve, which could be better served in solving the complex system issues of improving the hybrid system functionality. This paper describes the creation of a full resolver system simulation that can be used to prevent development issues, improve the hybrid system DFMEA, and act as a catalyst for solving development issues when they do happen.

This paper proposes a new development method for highly reliable real-time embedded control systems using a CPU model-based hardware/software co-simulation. We take an approach that allows the full simulation of the virtual mechanical control system including CPU and object code level software. In this paper, Renesas SH-2A microcontroller model was developed on CoMET™ platform from VaST Systems Technology. A ETC (Electronic Throttle Control) system and engine control system were chosen to prove this concept. The ETB (Electronic Throttle Body) model on Saber® simulator from Synopsys® or engine model on MATLAB®/Simulink® simulator from MathWorks can be simulated with the SH-2A model. To help the system design, debug and evaluation, we developed an integrated behavior analyzer, which can display CPU behavior graphically during the simulation without affecting the simulation result, such as task level CPU load, interrupt statistics, software variable transition chart, and so on.

The Wavelet Transform (WT) has been developed two decades ago, and has since then been put to use in an increasingly wide array of applications. The WT provides a time-scale analysis of a signal. Compared to the widely-popular Fourier Transform (FT), originally developed two hundred years ago, the WT provides the time-evolution of the signal at different scales. The Discrete Wavelet Transform (DWT) is a computationally efficient implementation of the WT, in which the time-scale analysis is performed on a dyadic scale. The DWT is very suitable for knock detection systems, since it can provide the history of the knock signal at discrete scales within a crank angle window. It allows for the extraction of a multitude of features from the time-scale plane. Moreover, the DWT is suitable for real-time knock detection implementations on engine control units.

The effect of fuel injection atomization on engine performance has been known to improve fuel economy and to reduce emissions. Hitachi America, Ltd. Research and Development along with Hitachi Research Laboratory in Japan have studied the effects and the operation of the air assist injection system which was developed and studied to help meet future Low Emission Vehicles (LEV) regulations and also Ultra Low Emission Vehicles (ULEV) regulations. The system consisted of newly designed air assist injectors having a spray angle of 15° at 170 kPa (absolute air pressure) with 370 kPa (absolute fuel pressure). The air assist injector generates highly atomized fuel droplets by swirling the fuel clockwise and the air counterclockwise. The fuel and air flowing in opposite directions collide, thereby producing particles around 30 μm in size at 274 kPa air pressure. These characteristics improve cold start, cold coolant conditions and fully warm engine conditions.

The key issue in gas metering of alternative fuel vehicle is to obtain low emission and accurate air-fuel ratio. A hot wire mass air flow sensor can directly monitor the air flow by using thermal transfer amount in an unit time to keep the hot wire at a certain temperature. Surveys were conducted regarding this method and it was verified that this method enables to monitor mass gas flow in applications such as Compressed Natural Gas(CNG) and propane(C3H8). The gas passage body for this sensor, which consists of a 10mm diameter bypass and a main pass has been surveyed and developed. This electrical sensing device for CNG has been completed and its performance was verified with a CNG flow test stand and a CNG engine. We have found that this thermal transfer monitoring method is not affected by a pressure change.

We have developed a full virtual engine system prototyping platform with 4-cylinder engine plant model, SH-2A CPU hardware model, and object code level software including OSEK OS. The virtual engine system prototyping platform can run simulation of an engine control system and digital knock detection system including 64-pt FFT computations that provide required high-resolution DSP capability for detection and control. To help the system design, debugging, and evaluation, the virtual system prototyping consists of behavior analyzer which can provide the visualization of useful CPU internal information for control algorithm tuning, RTOS optimization, and CPU architecture development. Thus the co-simulation enables time and cost saving at validation stage as validation can be performed at the design stage before production of actual components.