🚀 go-pugleaf

On 6 Aug 1997, Klaus Bernhard wrote:

> Why would one use state feedback ( and therewith Kalman filtering)
> instead of output feedback, when I can feed my controller with the
> latter one directly instead of estimating the states with an observer
> and so on...?
>=20
> Klaus
> --=20
> Klaus Bernhard
> Institut f=FCr Kraftfahrwesen Aachen      ika      Department of
> Automotive Engineering
> RWTH Aachen                                                  =20
> University of Technology Aachen, Germany
>=20
> Please remove the '_no'-string from my
> email adress if you reply directly
> klausb@ika.rwth-aachen.de
>=20
>=20

Well, there are many reasons for using state feedback
instead of output feedback. One of them is that there
may be unstable modes that are uncontrollable from the
output, but can be controlled by other states. In=20
classical control where only input-output information
(i.e., the transfer function) is used, one usually cannot
obtain satisfactory performance by using P-control alone.
A compensator, which somehow can be regarded as a
state feedback with state-estimator, is generally necessary.

Hualin Tan
ECE, JHU