Optimization methods aimed at designing a force control active mirror: II. Actuator pattern optimization

Autor: Jean-Louis Carel, Renaud Mercier Ythier, Pierre Coustal, Xavier Bozec
Rok vydání: 1997
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
Popis: In the part I of this publication, we have shown that an optimization of the pad allowed us to decrease the actuator number of the active mirror without degrading the performances requirements. The other way to improve performance is presented and discussed in this paper and consists in fitting the pattern of actuators to the set of deformations required in order to decrease the number of actuators. The method we have developed is based on a modal analysis of the mirror. Finite element calculation produces the first dynamic modes of the mirror. Each deformation is decomposed as a linear combination of the dynamic modes. The first step of the optimization is to estimate for a well defined pattern, the best effort vector to perform each mode and to calculate the error associated. The second step is to calculate a overall error taking into account the statistical characteristics of the deformation. The final step consist in the minimization of this error by moving the pattern of actuators. The method of optimization is fully detailed as well as the numerical process used to find the minimum of the error. Many results as well as the advantages of this method are presented. Application of this method to the design of the active mirror of the Laser MegaJoules (French Ignition Program) is mentioned.
Databáze: OpenAIRE