Method and apparatus for improved control of piezoelectric positioners
US5714831A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1995 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | Nov 13, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/851
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A piezoelectric positioner is accurately controlled to reduce the settling time of the positioner in response to a commanded change in position using velocity state feedback control. The velocity state feedback control uses an estimated velocity of the piezoelectric positioner generated by a velocity observer to provide active damping. The velocity observer has as inputs the same control signal which is provided to the piezoelectric positioner itself and the actual measured position of the positioner, and produces as an output the estimated velocity of the positioner. The velocity observer includes a model of the piezoelectric positioner's response to the control signal. The model includes estimates of physical parameters of the positioner including the physical mass, physical damping, and physical stiffness of the positioner. Position and velocity state feedbacks are used within the observer model, in combination with the actual measured position of the positioner, to drive a modeled position of the positioner to equal the actual position, thereby also to increase the accuracy of the velocity estimate. The observer state feedbacks reduce errors in the modeled position due to inacc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.