Adaptive optics (AO) instruments for the future extremely large telescopes (ELTs) are characterized by advanced optical systems with diffraction-limited optical quality. Low geometric distortion is also crucial for high accuracy astrometric applications. Optical alignment of such systems is a crucial step of the instrument integration. Due to relative inaccessibility of these giant instruments, automatic alignment methods are also favored to improve the instrument availability after major events, such as extraordinary maintenance. The proposed alignment concept for these systems is described: the notable example which is analyzed here is the case of the multiconjugate AO relay for the future ELT. The results of ray-tracing simulations carried out to validate the method are discussed in detail, covering the error sources, which could degrade the alignment performance.
MAORY is one of the approved instruments for the European Extremely Large Telescope. It is an adaptive optics module, enabling high-angular resolution observations in the near infrared by real-time compensation of the wavefront distortions due to atmospheric turbulence and other disturbances such as wind action on the telescope. An overview of the instrument design is given in this paper.
MAORY (Multi Conjugate Adaptive Optics RelaY) is one of the four instruments for the ELT (Extremely Large Telescope) approved for construction. It is an adaptive optics module able to compensate the wavefront disturbances affecting the scientific observations, achieving high strehl ratio and high sky coverage. MAORY will be located on the straight-through port of the telescope Nasmyth platform and shall re-image the telescope focal plane to a wide field camera (MICADO) and a possible future second instrument. A trade-off study among different mechanical design options for the main mechanical structure has been carried out. This paper outlines an overview of the mechanical design that gives a better result in terms of stability, vibrations and manufacturing.
This work is focused on the analysis of optomechanical mountings based on hexapodal kinematics architecture to obtain efficient supports and proper alignment of an optical device. It has been implemented a parametrized approach considering different conditions of load in terms of operative and survival conditions for the analysis. The project is organized in the following steps: <p> </p><ul>
Definition of the structure with all the geometrical parameters as input for the code. Any type of initial condition (dimension and shape) can be considered starting from the kinematic chain between each part.<p> </p> Definition of all the parameters required for the analysis. All the physical proprieties of the materials are defined in terms of mechanical and thermal behavior. <p> </p> Definition of the proper mesh, with the selection of proper elements type, boundary conditions and applied loads.
<p> </p> Thanks to these three steps is possible to obtain practically any layout. Realistic survival and operational requirements of both ground and space based application has driven the analyses done. A comparison between the numerical simulations and a real example has been done to validate the modelling technique. The final result is a validated code with user’s interface, and a parametric analysis of the behavior of the optomechanical mountings based on hexapodal kinematics architecture.