Béarée, Richard (2005) Toward the integration of vibratory phenomena int he command generation of high-dynamics machine-tools. PhD thesis Automatique, ENSAM 2005ENAM0030.

Full text available as: - These-Bearee.pdf ( 4093 Kb )

Licence: Copyright

Abstract

The increasing demands in terms of productivity lead the high-dynamics systems to the maximum of their technological and structural capacities, invalidating the classical assumption of a rigid body dynamics. Consequently, the system control cannot neglect the influence of the vibratory phenomena on the accuracy of the contour tracking, but it has to modulate the command efforts in order to realize the adequacy between the intrinsic system characteristics and the speed and accuracy criteria. This study aims at improving the dynamic behavior of these machines by a direct action on the command generation. The command generation is divided into two main functions: (1) the elaboration of a movement law for the system states to control, which is used as reference for controls (indirect control) (2) the definition of a prefilter transforming the movement law into a reference signal for the input of the physical system (direct control). If correctly managed, these two functions make it possible to dissociate the regulation and the contour tracking problems. Initially, they are specifically study in the case of one axis movement. Thus, the influence of various movement laws (harmonic, polynomial, piecewise polynomial or multi-switch bang-bang law) on the vibrations and on the movement time is formalized. A design methodology for the prefilter adapted to the flexibilities of an axis is presented it puts forward the required degree of continuity, which the law of movement must satisfy. Then, after experimental validations on several high-dynamics test-setups, the results and methodologies are adapted to the contour-tracking problem for two Cartesian axes.

Statistiques de consultation

Repository Staff Only: edit this item