Input to Output Linearization with Constrained Measurements

Many pracitcal control applications require nonlinear control concepts to fulfill the high demands on the performance. Often, differential geometric methods, like the well established exact input-to-state or input-to-output linearization approach are not applicable, since the implementation of the feedback law requires the measurement of the whole state. This contribution deals with a refinement of the input-to-output linearization such that the control law depends only on a predefinded set of measurements. More precisely, we derive the determining equations for one output function in the single-input, or a set of output functions in the multi-input case, such that the input-to-output map from the new input to the new output is linear and such that the feedback law uses predefinded measurements only. Finally, this approach is applied to a hydraulic positioning systems.