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This paper presents a brake pressure estimation algorithm for Delphi Traction Control Systems (TCS). A control oriented lumped parameter model of a brake control system is developed using Matlab/Simulink. The model is derived based on a typical brake system and is generic to other types of brake control hardware systems. For application purposes, the model is simplified to capture the dominant dynamic brake pressure response. Vehicle experimental data collected under various scenarios are used to validate the algorithm. Simulation results show that the algorithm gives accurate pressure estimation. In addition, the calibration procedure is greatly simplified

This paper describes an environment for the development of production Engine Management Systems (EMS). This includes a formal framework and modeling methodology. The environment is based on using Simulink/Stateflow for developing a control system executable specification and a plant model. This allows for simulations of the system to be performed at the engineer's desk, which is identical performance with production software. We provide the details for incorporating production legacy code into the Simulink/Stateflow control system. The system includes a multi-rate, and event driven operating system. This system is developed to facilitate new algorithm development and automated software testing. Based on Simulink/Stateflow this specification will be suitable for use with commercial automatic code generation tools.

Both evaporative emissions and tailpipe emissions have been reduced by more than 90% from uncontrolled levels in state-of-the-art. However, now that the objective is to reach near-zero emission levels, the need for aggressive purging of the canister and fuel tank and the need for extremely precise control of engine Air/Fuel ratio (A/F) come into conflict. On-board diagnostics and the wide variation in operating conditions and fuel properties in the “real world” add to the challenge of resolving these conflicting requirements. An advanced canister purge algorithm has been developed which substantially eliminates the effect of canister purge on A/F control by estimating and compensating for the fuel and air introduced by the purge system. This paper describes the objectives and function of this algorithm and the validation of its performance.

Since the late 1980s, Delphi Automotive Systems has been very involved with the practical development of a variety of Collision Avoidance products for the near- and long-term automotive market. Many of these complex collision avoidance products will require the integration of various vehicular components/systems in order to provide a cohesive functioning product that is seamlessly integrated into the vehicle infrastructure. One such example of this system integration process was the development of an Adaptive Cruise Control system on an Opel Vectra. The design approach heavily incorporated system engineering processes/procedures. The critical issues and other technical challenges in developing these systems will be explored. Details on the hardware and algorithms developed for this vehicle, as well as the greater systems integration issues that arose during its development will also be presented.

Compromises inherent with fixed valve lift and event timing have prompted engine designers to consider Variable Valve Actuation (VVA) systems for many decades. In recent years, some relatively basic forms of VVA have been introduced into production engines. Greater performance and driveability expectations of customers, more stringent emission regulations set by government legislators, and the mutual desire for higher fuel economy are increasingly at odds. As a solution, many OEM companies are seriously considering large-scale application of higher function VVA mechanisms in their next generation vehicles. This paper describes the continuing development progress of a mechanical VVA system. Design features and operation of the mechanism are explained. Test results are presented in two sections: motored cylinder head test data focuses on VVA system friction, control system performance, valve lift and component stress.

Adaptive Cruise Control (ACC) technology is presently on the horizon as a convenience function intended to reduce driver workload. This paper presents an implementation of a brake algorithm, which extends the production cruise control feature. A brief overview of the system architecture and subsystem interfaces to the forward-obstacle detection system, throttle and engine management controls are described. Considerations of moding ACC with ABS and Traction Control are presented at the vehicle level. This development activity is presented in two major phases. Both phases of this development project utilize CAN controllers and transceivers to implement requirements for limited access highway driving. The initial phase of development requires the brake control to follow a deceleration command and operate “open-loop” to the vehicle controller. Vehicle test data capturing smooth stops on high coefficient surfaces is presented as insight to the braking performance of the vehicle.

This paper describes a semi-active damping control system that responds in real-time to road and driving conditions based on body motions as determined through ABS wheel speed sensors. The use of these existing sensors for vehicle information eliminates the need for the additional sensors (e.g. accelerometers and body-to-wheel position/velocity sensors) that are commonly part of semi-active suspension systems. This technology also allows for further cost and part count reductions through the combination of the suspension and brake controls into a single electronic control unit. This paper has been previously presented in 1998 at the SAE Controlled Suspension System Toptec.

The problem being investigated involves a noise-quality issue on a power steering application, when a sudden change of steering wheel angle generates an unwanted steering system noise or “Squawk.” This phenomenon is mostly observed during parking maneuvers, especially at lock positions and when the hydraulic fluid reaches a critical temperature on the specific application. The objective of the work to solve this noise-quality issue was to first identify the cause and then eliminate the Squawk noise. There were several constraints: No change could be made in the properties or type of hydraulic fluid used due to specification requirements; Steering wheel valve torsion bar characteristic (torque vs. angle) needed to be maintained within specification for ride and handling purposes; and, In addition to the mentioned constraints, a high capability of noise elimination generated by the production tolerances and dispersion has been considered.

The electric power required in automotive systems is quickly reaching a level that significantly impacts costs and fuel consumption. This drives the need to reconsider an electric energy management function. Fast evolving factors such as increasing power usage, and stricter engine management and reliability requirements necessitate a global vehicle approach to energy management. Innovations such as new powernet concepts (42 volt or dual voltage systems), new component technologies (high-performance energy storage, high efficiency and controllable generators), and global electronic and software architecture concepts will enable this new energy management concept. This paper describes key issues to maximize energy availability with reasonable components.

The complexity of automotive software and the needs for shorter development time and software portability require the development of new approaches and standards for software architectures. The AUTOSAR project is one of the most comprehensive and promising solutions for defining a methodology supporting a function-driven development process. Furthermore, it manifests itself as a standard for expressing compatible software interfaces at the Application Layer. This paper discusses the implementation of AUTOSAR requirements for the component structure, as well as interfaces to the Application Layer in a model-based development environment. The paper outlines the major AUTOSAR requirements for software components, provides examples of their implementation in a Simulink/Stateflow model, and describes the modelbased implementation of an operating system for running AUTOSAR software executables (“runnables”).

Today automotive system suppliers develop more-or-less independent systems, such as brake, power steering and suspension systems. In the future, car manufacturers like Volvo will build up vehicle control systems combining their own algorithms with algorithms provided by automotive system suppliers. Standardization of interfaces to actuators, sensors and functions is an important enabler for this vision and will have major consequences for functionality, prices and lead times, and thus affects both vehicle manufacturers and automotive suppliers. The investigation of the level of appropriate interfaces, as part of the European BRAKE project, is described here. Potential problems and consequences are discussed from both a technical and a business perspective. This paper provides a background on BRAKE and on the functional decomposition upon which the interface definitions are based. Finally, the interface definitions for brake system functionality are given.

Intense competition in the automotive industry requires continuous reduction in innovation cycle time, even as corporations are downsizing and system complexity is increasing. Subsequently, the application of recently introduced Rapid Algorithm Development (RAD) tools has facilitated significant advances in the development of embedded control systems. The RAD steps include system modeling, control algorithm design, simulation analysis, automated calibration design, and vehicle implementation through automatic code generation. The application of RAD tools and the associated benefits are described, specifically in the context of Engine Management Systems (EMS). Such benefits include significant reductions in development cycle time, open architecture, automated calibration, and information reuse.

Short timing and complexes strategies are mandatory in a competitive market as automotive industry. Therefore quality problems identification during and after the coding phase, may be the difference between the business success and undesired conflicts with customer, solving problems that were not previously identified. Consequently the usage of technique Mahalanobis Taguchi System (MTS) to analyze coding metrics, create an environment to improve the final product quality and mitigate potential problems later identified.

Our customers expect in their vehicles the same constant connectivity that they experience in their homes through high speed internet portals. New services based on these advances will be transparent and ubiquitous - completely integrated into our lives, just as electricity comes to the wall socket or water from the faucet. The Wi-Fi Radio implements this vision using Wireless Fidelity (Wi-Fi) based on the suite of IEEE 802.11 standards. Drivers have constant wireless connectivity and personalized digital content made available to them through the Wi-Fi Radio. Ford and our partner Delphi developed the Wi-Fi Radio to overcome the inherent functional and packaging limitations of our vehicles, to quickly introduce new technology at affordable prices and to seamlessly integrate new services into the vehicle. We chose the radio as the integration site because the radio is accessible to every customer and affordable on every vehicle.