Coupling Modeling and Adaptive Control for Piezoelectric-Actuated Positioning Stage

Table 3

The relative error of the Hammerstein model and the proposed coupling model.

Frequency (/Hz)	The relative error
	The Hammerstein model	The proposed coupling model
1	4.79%	1.86%
10	4.21%	1.22%
20	3.26%	1.16%
50	3.57%	1.55%
100	2.81%	2.05%
5/40/80	2.12%	1.21%