The field of nonlinear control has gathered increasing importance during the
last decades and is still — or rather more than ever — a very active field
of research. Thereby, the development of nonlinear control theory and design
is directly linked to the progress in theory and design of nonlinear observers.
For instance, the differential geometric viewpoint had impact in both research
areas. Another important aspect linking both fields is the fact that modern
nonlinear control laws usually require full or at least partial state information,
such that the classical control–loop has to be amended by an observer.
Besides research, nonlinear control and observer design and especially their
realtime realization and implementation enters more and more into industrial
applications. Particularly in the fields of automotive engineering and mechatronics,
higher control performance is demanded with the simultaneous demand
of actuator and sensor size reduction. Additionally, market pressure
increases the demand to reduce costly sensors, such that signals have to be
reconstructed mathematically.