Automotive Powertrain Controller Development Using CACSD

Abstract

Reducing the cost and time associated with developing and deploying new control systems is a challenge facing all industries that rely extensively on control technology. The automotive industry furnishes a prime example, especially for powertrain control development. Computer-aided control system design (CACSD), a topic discussed in some generality in Chapter 3, provides the enabling tools for meeting this challenge. (For another example of an important application domain for CACSD, see Chapter lion flight control.) This chapter discusses in detail the process of developing automotive powertrain controller software. Powertrain control systems can be highly complex, integrating a number of different subsystems: fuel injection, throttle control, idle speed control, vehicle speed control, engine torque management, emissions control, knock detection, electronic transmission control, on-board diagnostics, and numerous others. The overall design must satisfy constraints and criteria imposed by government (such as fuel economy standards and emission thresholds), the corporate environment (which may demand support for legacy systems in addition to cost minimization and rapid time to market), and consumer preferences. To address the complexity of powertrain controller development, Ford Motor Company employs a systems engineering process. The emphasis is on validation or verification of products of all intermediate development stages, on the widespread implementation of feedback mechanisms, and on the continuing availability of support from engineering analysis and design teams. A requirements-based and CACSD- enabled development process has been implemented which incorporates requirements capture; architecture design; control feature design, implementation, and verification; and software validation, verification, and integra tion. The chapter also highlights the role of effective project management in large-scale control system development. Project management metrics can be integrated within the development process, and in the case of Ford these helped justify the CACSD project investment. Statistical data demonstrating the improvement in control software quality due to automation supported by CACSD tools is included.