New Approaches to Electronic Throttle Control 910085
An electronic control of throttle angle is required for safety systems like traction control (ASR) and for advanced engine management systems with regard to further improvements of driving comfort and fuel economy. For applications, in which only ASR is required, two versions of a new traction control actuator (TCA) have been developed. Their function is based on controlling the effective length of the bowden cable between the accelerator pedal and the throttle. Besides retaining the mechanical linkage to the throttle, the concept has no need for a pedal position sensor, which is necessary for a drive-by-wire system. Design and performance of both actuators are described and their individual advantages are compared. Moreover, the communication of the system with ASR and its behaviour with regard to vehicle dynamics are illustrated.
In contrast to the TCA concept, drive-by-wire throttle control is able to perform many other functions, as for instance idle speed control, cruise control, negative and positive dashpot or throttle-to-pedal angle-mapping. After a brief survey over systems, which are already in production, a new actuator concept with several novel features is presented. Furthermore, the state-of-the-art of engine and vehicle related functions is described and the potential for further improvements is discussed.