This paper presents a simple solution to increase the stability of the large superstructures supporting the final electromagnets of future linear particle collider. It consists of active carbon fiber tie rods, fixed at one end on the structure and at the other end to the detector through active tendons. In the first part of the paper, the solution has been tested on a finite element model of one half of the CLIC_ILD final focus structure. With a reasonable design, it is shown numerically that the compliance can be decreased by at least a factor 4, i.e., that the structure is 4 times more robust to technical noise at low frequency. Two additional features of the active rods are that they can also actively damp the structural resonances and realign the superstructures. The second part of the paper presents a successful experimental validation of the concept, applied to a scaled test bench, especially designed to contain the same modal characteristics as the full scale superstructure.
Received 31 October 2012Accepted 15 January 2013Published online 04 February 2013
The research leading to these results has been funded by the Brain Back to Brussels program from Brussels Capital Region. The authors also gratefully acknowledge Bastien Legrand for his help in the calculations, Arnaud Mewissen for inspiring discussions on the mechanical design, and Julien Amar for his help to conduct the experiments.
Article outline: I. INTRODUCTION II. SUPERSTRUCTURE STABILIZATION A. Finite element model B. Tie rods design C. Structural control with active tendons III. SCALED TEST BENCH A. Modeling and simulations B. Structural control C. Experimental results IV. CONCLUSIONS
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