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A mature process for the development of embedded controls and systems using Model-Based Design relies on libraries of validated models for the physical system components. These models are used throughout the design process and are readily available to the system and controls engineers for design and validation tasks. Models are created at various levels of abstraction to accommodate analysis needs at various stages of the design process. Abstract models are used early in the process for quick assessment of design tradeoffs, while higher fidelity models are used as the design progresses to account for the dynamics that affect system performance. Once acceptable system performance is achieved with desktop simulation, the models are moved to a real-time platform for final verification. Creating real-time capable plant models typically requires making assumptions and compromises to achieve acceptable performance.

As automotive electronics become more complex and more distributed, hardware in-the-loop simulation is now a widely adopted technique for performing controller software/hardware integration testing as well as controller/controller integration testing. Having real-time capable models that are correlated to physical hardware being controlled is key to successful implementation of hardware in-the-loop testing. Because models for hardware in-the-loop must be developed in a short amount of time and then stay in sync with the design through design changes, a best practice is to obtain such models from the system-level model used for requirements analysis and design trade offs. This way, one model can address the need of both requirements analysis and integration testing, reducing redevelopment of models and ensuring consistency between two process steps.

Today’s automotive control system engineering requires precision and accuracy. The cost of a controller designed with conservative margins may increase significantly, causing the design, when produced and marketed, to be less competitive. On the other hand, a design with too little margin may lead to system malfunction under marginal environment conditions or due to component aging. A robust design is one that is immune to the effects of component variance due to tolerance, temperature, and aging, among other factors. Achieving a robust design involves careful analysis of the controller and plant operating together. This paper discusses how MATLAB and Simulink can be leveraged to ensure the robustness of a mechatronic system design. The merits of the network approach as a technique for modeling physical systems as an alternative to the signal flow (block diagram) approach are also discussed.

Commercial vehicle manufacturers face unique challenges for the development of vehicle electronics systems. For one, customers typically have unique requirements coupled with an expectation of high reliability. Vehicle electronics is often the enabler for customized features. Ensuring that the vehicle will perform as demanded and promised adds a degree of burden on the vehicle manufacturers. Furthermore, the verification and testing of a large number of unique electronic system configurations is very expensive and time-consuming. This paper will explore how Model-Based Design can be used to meet these challenges and provide a high degree of confidence for both the manufacturer and the customer that requirements have been met. It will discuss factors to consider to support configurability, approaches for defining a system architecture that facilitates reuse, and capabilities for modeling state-based systems.

In this paper, we show how Model-Based Design can be applied in the development of a hybrid electric vehicle system. The paper explains how Model-Based Design begins with defining the design requirements that can be traced throughout the development process. This leads to the development of component models of the physical system, such as the power distribution system and mechanical driveline. We also show the development of an energy management strategy for several modes of operation including the full electric, hybrid, and combustion engine modes. Finally, we show how an integrated environment facilitates the combination of various subsystems and enables engineers to verify that overall performance meets the desired requirements.

The need to meet new regulatory requirements as well as customer expectations in terms of machine productivity, safety, maintenance and uptime, is driving a significant transformation from conventional hydraulic and mechanical systems to electro-hydraulic systems in the earth-moving and agricultural equipment industry. The ability to model and simulate such systems plays a key role in this transformation by allowing manufacturers to test whether the system meets requirements using virtual prototypes rather than physical prototypes. Modeling the electrical, electronic, mechanical, and hydraulic domains in the same modeling environment can significantly improve the product development process of such machines. This paper illustrates those benefits using the example of an electro-hydraulic implement system.

The low cost of microcontrollers makes them increasingly popular for electronic control of a wide range of embedded systems throughout the vehicle. An embedded mixed-signal or mechatronic system is one that uses a microcontroller to control some aspect of the physical system such as motion, speed, temperature etc… The added dimension of software presents a significant challenge to the design, integration and verification of this class of systems. This paper will discuss how the VHDL-AMS language can be used to describe the behavior of the physical hardware along with the controlling software algorithm together in a unified system model. This unifying technology can provide invaluable insight to the embedded system designer during the system design, integration, verification and debugging phases.

VHDL-AMS, approved by the IEEE in 1999, is the first industry standard hardware description language (HDL) for modeling the many mixed-technology components that exist in modern automotive systems and subsystems. Technologies include electrical (analog and digital), mechanical (rotational and translational), fluidic, magnetic, thermal, etc. VHDL-AMS is a valuable tool for understanding the complex interaction between these technologies, which is essential for the today's engineers in achieving their design goals. In this study, the VHDL-AMS language is used to mathematically model the individual components that form the drivetrain system of an automobile. The components modeled are the engine, clutch, transmission, final drive (differential), drive shaft, brake, wheel, chassis, air drag, and driver. A graphical design environment is used to interconnect the components into system and subsystem models for simulation and analysis.

Math-based Computer-Aided Prototyping (CAP) is a new and highly effective design methodology. Using math-based CAP, engineers create realistic “virtual” prototypes for a wide range of circuits and dynamic systems. The purpose is to gain understanding and ultimately improve their designs, as well as to share information and coordinate design knowledge. VHDL-AMS (IEEE Std. 1076.1) is the technology standard that makes math-based CAP possible. VHDL-AMS is a versatile Hardware Description Language that is capable of describing analog and digital electronics, as well as non-electrical components with equal fidelity and accuracy. This makes it well suited for virtual prototyping of advanced automotive mechatronic systems. This paper illustrates math-based CAP methods and key VHDL-AMS modeling capabilities through several examples. These methods are applicable for the design of various types of automotive systems including Electrical, Powertrain, and Vehicle Control.

An increasingly important, yet often underestimated task of modern vehicle design is the system interconnect, commonly known as the wire harness. The continual increase in on–board vehicle electronics is causing an exponential expansion in wire harness complexity. To meet these challenges, software tools have been developed to assist the harness designer in the various tasks from system partitioning to signal integrity analysis. This paper will discuss the key problem areas of the wire harness design, along with the design and analysis capabilities of the SaberHarness™ tool suite.