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Automotive vehicles today consist of very complex network of electronic control units (ECU) connected with each other using different network implementations such as Controller Area Network (CAN), FlexRay, etc. There are several ECUs inside a vehicle targeting specific applications such as engine, transmission, body, steering, brakes, infotainment/navigation, etc. comprising on an average more than 50 ECUs executing more than 50 million lines of software code. It is expected to increase exponentially in the next few years. Such complex electric/electronic (E/E) architecture and software calls for a comprehensive, flexible and systematic development and validation environment especially for a system level or vehicle level development. To achieve this goal, we have built a virtual multi-ECU high fidelity cyber-physical multi-rate cosimulation that closely resembles a realistic hardware based automotive embedded system.

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 decentralized design environment that has become common practice in automotive electronics poses an especially difficult challenge to product design. Hardware and software teams may span both organizational and geographic boundaries. This makes it impractical to share a common laboratory facility for component testing and system integration. Simulation models can be shared across these boundaries but to serve as a prototyping alternative these simulations must model the hardware in detail and must execute the software. This paper presents such a virtual prototype using VHDL-AMS to model the hardware and to implement a micro-controller model that executes the software with accurate timing. An electronic throttle subsystem is simulated to demonstrate how the virtual prototype can be used to assess hardware/software interactions, verify compliance of the component designs with specifications, and optimize the trade-offs between numerical precision and software timing.

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.

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.