Ralf Schwarz

Application of LQ-based semi-active suspension control in a vehicle

Abstract A linear quadratic (LQ) based controller and observer concept for a semi-active full-car model is implemented and compared to a skyhook controller using a real vehicle in this paper. Especially an observer including a new modified road model is presented, which reliably filters low frequency disturbances induced by ascending or descending steep hills. Furthermore, methods for the parametrization of the quadratic cost function are presented and it is shown in experiments for different vehicle masses that ride comfort and road holding can be significantly improved by using semi-active suspension control. In order to take nonlinear component characteristics or suspension friction into account a parametrized nonlinear full-car model is presented, which is used for the determination of the controller cost function weights. The performance evaluation is done using a 4-poster test rig as well as measurements conducted on a real road.

Systemvernetzung und Funktionseigenentwicklung im Fahrwerk — Neue Herausforderung für Hersteller und Zulieferer

Innovationen in der Automobilindustrie kamen in den letzten Jahren vor allem aus der Elektronik. Die Bedeutung der Elektronik und ihrer Funktionen wird auch in Zukunft weiter steigen. Die Elektronifizierung hat jedoch noch ihre Kehrseiten. Laut einer vom ADAC 2004 in Auftrag gegebenen CAR-Studie ist in Deutschland in den letzten funf Jahren der Anteil der Pannen bei drei- bis funfjahrigen Autos, die auf Elektrik und Elektronik zuruckzufuhren sind, von 50,5 auf 59,2 Prozent gestiegen. Aufgabe der OEMs und Zulieferer muss es daher zukunftig verstarkt sein, die Verfugbarkeit der Funktionen bei gleichbleibender Innovationsgeschwindigkeit zu erhohen, dies wird durch partnerschaftliche Zusammenarbeit mit neuen Wegen der Entwicklungsverzahnung ermoglicht. Mit dem Leitsatz „Vorsprung durch Technik“ folgt daraus fur Audi der Anspruch:

Achieving functional safety of audi dynamic steering using a structured development process

Abstract Audi dynamic steering is a safety relevant electronic steering system. In order to achieve functional safety for this system a structured development process including all safety process aspects and several support processes have been defined and installed. Furthermore, the compliance of the implemented processes with the defined processes is strictly monitored by the internal quality assurance. Additionally, an external assessor is accompanying the product development in order to assure the functional safety of the product according to the requirements of international safety standards. Besides the enforcement of the processes, the challenge in this project is the coordination and monitoring of three suppliers together with the quality assurance and the external assessor.

Central signal processing unit for chassis control systems

The increasing number of chassis control systems asks for solutions regarding the new complexity. One strategy is the integration of common functionalities to central entities. Premise for a central approach in the chassis domain is a standardised signal processing unit that provides common and consistent signals for all involved control systems. Arising challenges, possible strategies and the chosen approach of Audi are described in the following.

ESP II driving dynamics in the next generation

ESP II from Continental Teves, the next generation of the well-known driving dynamics control system ESP, utilizes active steering intervention for the first time and thereby not only provides greater handling safety but also creates new dimensions of driving pleasure and ride comfort. The system makes the vehicle easier to control at critical limits and offers more agility for handling. The optional incorporation of suspension control, e.g., by means of adjustable dampers, rounds off this first step on the way to the networked chassis (Global Chassis Control).

ESP II Fahrdynamik der nächsten Generation: Teil 2: Funktionsintegration und Elektronik

ESP II von Continental Teves nutzt erstmals aktive Lenkeingriffe und bietet damit nicht nur mehr Fahrsicherheit, sondern eroffnet auch neue Dimensionen an Fahrspas und Fahrkomfort. Das System macht das Fahrzeug im Grenzbereich leichter beherrschbar und verleiht ihm im Handlingbereich mehr Agilitat. Teil 2 berichtet uber Funktionsintegration und Elektronik.