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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.

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.

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.

In the past few years, the demands for more complex system development and the ever-increasing requirement for hardware and software improvements have increased the need for a virtual embedded system where the hardware, microcontroller and software co-exist at the simulation level. This paper discusses the implementation of an approach that allows the full simulation of the embedded system. In the scope of this paper the definition of an embedded system refers to the electro-mechanical plant, the microcontroller, the peripherals and the software. The sensors and actuators are developed with a conservative type simulator such as Saber from Synopsys. The microcontroller and the attached peripherals are developed and modeled with the Comet environment from VaST. The microcontroller simulator is instruction cycle accurate. We are describing an innovative concept that will allow co-simulation between the two simulators.

In the past few years, the demand for more complex system development and the ever-increasing requirement for improvement in software productivity have amplified the need for graphical programming and automatic generation of controller software. This paper discusses the implementation of graphical code generation in the context of a fully automated calibratable system. Generally, controller parameters coarse tuning is done at the simulation level with a virtual plant and then fine-tuned when the code is downloaded onto the target controller. The tuning process is then based on trial and error approach relying on experienced calibrators to perform this tedious work. We are proposing an innovative concept that will automate the whole process of controller development. This process goes from the control algorithm code generation to the real-time calibration of the controller parameters on the actual target controller.

Accurate simulation model of Electronic Throttle Body (ETB) is important to engine control, system analysis and diagnosis. However, some model parameters could vary significantly due to temperature variation and harsh working environment, therefore are very difficult to calibrate in test. In this paper, an optimization of model parameters with genetic algorithm is implemented to match simulation with open loop step and impulse response test results to achieve a precise ETB model. Closed loop validation test with rapid prototyping tool is accomplished to confirm the accuracy of simulation model. This automatic parameter-refining modeling approach turns out to be an efficient way to achieve the required model accuracy, which utilizes the advantages of multi-software tool chain.

As the demand for more complex system development and the ever-increasing requirement for improvement in software productivity, the need for graphical programming or Zero-Hand Coding for automatic generation of controller software becomes highly desirable. The graphical programming must not be limited to the algorithm development which consists of the application modules but must be extended to the microcontroller platform, which include the middleware (i.e. operating system, I/O device drivers) and hardware. Automatic code generation is very important for programming the complex microcontroller internal parameters and registers. The combined software tool chain is to generate the final target specific executable code. This approach is very beneficial for system development, reduction of the development cycle and bridges the gap between control and software engineers reducing time, effort and cost of the production software.

A new hydrogen flow sensor was designed and evaluated based on the concept of hot wire anemometry. This sensor is designed to measure the mass flow rate of hydrogen gas used in (but not limited to) proton exchange fuel cell, PEFC. The conceptual evaluation was initiated by deriving an electro-thermal model of the hot wire required for sensing hydrogen velocity. The modeling is done via a mechatronics software tool, Saber™. This model was validated using air as a medium. Simulated and experimental performance results and safety issues are presented and discussed in this paper. Fail safe methods and effectiveness have been investigated along with hydrogen ignition temperatures with varying hydrogen to air ratio.

The usage of Compressed Natural Gas (CNG) engines is increasing as requirements for cleaner emissions are required by state and federal agencies such as C.A.R.B. and E.P.A. Also, to further reduce emission levels, tighter air/fuel ratio control is required. There are many ways to control air/fuel ratio on a CNG engine. It can be performed in a feedforward method, a feedback method or a combination of both. CNG fuel can be introduced to the engine via single-point injection, multi-point injection or with an air/gas mixer. Mixer-type and single-point injection are good candidates for the application of a gas flow sensor for accurate air/fuel ratio measurement. Reduction of valve hysteresis can also be achieved. Fuel delivery and control systems cost can be kept low compared to using multi-point injection where high flow injectors are required for each cylinder. A gas flow sensor is placed in the CNG stream to monitor mass gas flow rate.

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.

A new Gas Flow Sensor was derived from the current air flow sensing technology. This sensor is targeted at measuring the amount of gaseous mass flow under high pressure and with varying gas temperature. Thermodynamical properties of CH4, air, N2He and CO2 have been compiled at different pressures and temperatures. This information is required for the simulation. A theoretical model has been developed to analyze the behavior of the sensor circuit with different gases at varying pressure and temperature. The theoretical model encompasses a model of the gas flow circuit as well as a flow model with an optimized fluid dynamic equation. Fluid dynamics have also been studied to demonstrate the usage of a bypass and a mesh screen for flow regulation. A finite element analysis (FEA) is also generated to study the velocity profile and potential turbulence areas.

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.