A new flatness-based control of lateral vehicle dynamics

Abstract

This paper presents a new concept for vehicle dynamics control (VDC). The control of the longitudinal vehicle dynamics is not discussed, since we are assuming that it is much slower and weakly coupled to the lateral and yawing dynamics. The actuators are considered to be the traction and the braking torques of the individual wheels and only the standard sensors of the common VDC system are used. A modular interface to the subordinate wheel control system is provided by choosing the yaw torque as a fictitious control input. The VDC system is designed by means of a two degrees-of-freedom control scheme. It comprises a flatness-based feedforward part and a stabilising feedback part. The reference trajectory generation is introduced for the flat output which is given by the lateral velocity of the vehicle. Thus an advantageous kind of body side-slip angle control is provided with the standard VDC system hardware. Extensive simulation studies show excellent performance of the designed control concept.

Comparison of trajectory tracking controllers for emergency situations

“…For example, individual wheel steering [14], differential breaking of leftand right wheels [1] as well as differential breaking of front and rear wheels [17] may lead to flat systems. Alternatively, the system description may be simplified, e.g., neglecting the longitudinal dynamics [2], [23] or focusing only on velocities and neglecting the vehicle position [7]. It is also known that the zero side-slip assumption of a kinematic vehicle model facilitates flatness [20].…”

Zur Kombination von differenzieller Flachheit und Backstepping für die Trajektorienfolgeregelung eines Diffusions-Konvektions-Reaktionssystems

“…Gleichzeitig ist in vielen industriellen Anwendungen eine Abkehr von der reinen Stabilisierung eines Arbeitspunktes hin zur Realisierung von spezifischen Anfahr-, Ü bergangs-und Folgevorgä ngen zu beobachten, welche inhä rent die Lö sung einer Trajektorienfolgeaufgabe erfordern. Als industrielle Beispiele sind hierbei u. a. die Regelung verfahrenstechnischer Prozesse (Petit et al, 2002;Corriou, 2004), die Positionsregelung von hydraulischen Systemen (Fuchshumer et al, 2007;Kemmetmü ller et al, 2007) oder die Fahrdynamikregelung (Fuchshumer et al, 2005;Antonov et al, 2008) zu nennen.…”

Flatness-based electronic posture control (EPC) for accident avoidance

“…Several contributions have been developed to improve vehicle control stability at the limit of handling conditions (see [8]). Works on obstacle avoidance using a flatness-based approach have also been performed (see [1], [5], [11]). However, to the best of our knowledge, none of these works are dealing with extreme posture control in a differential flatness-based framework.…”