Preliminary aero-mechanical jitter analysis of hemispherical turrets

Timothy J. Bukowski; R. Mark Rennie; Stanislav Gordeyev; Matthew Kemnetz

doi:10.1117/12.3028193

7 October 2024 Preliminary aero-mechanical jitter analysis of hemispherical turrets

Timothy J. Bukowski, R. Mark Rennie, Stanislav Gordeyev, Matthew Kemnetz

Proceedings Volume 13149, Unconventional Imaging, Sensing, and Adaptive Optics 2024; 131490E (2024) https://doi.org/10.1117/12.3028193
Event: Optical Engineering + Applications, 2024, San Diego, California, United States

Abstract

This work presents preliminary results on aero-mechanical jitter of a hemispherical optical turret. A simplified geometry with a hemispherical shell and optics-holding canister was designed to reduce degrees of freedom and provide better insight into fundamental physics. Modal analysis of the turret and mounting plate to the wind tunnel, performed using finite element analysis (FEA), revealed significant plate displacements in the lowest frequency modes. Three mounting plate thicknesses (1/4”, 1/2”, and 1”) were tested. Wind tunnel tests at the University of Notre Dame’s White Field Mach 0.6 wind tunnel assessed turret vibrations at speeds from Mach 0.2 to 0.5, using accelerometers and Shack-Hartmann tilt sensors. Two scenarios were tested: one with the turret inside the tunnel exposed to the flow, and another with the turret attached outside of the wind tunnel so that it is only excited by the base motion of the wind tunnel. The 1/4” plate showed tilt measurements ranging from 30 to 190 microradians when exposed to flow, compared to 10 to 50 microradians in the baseline case. The 1/2” and 1” plates exhibited lower tilts and less distinction between flow and baseline conditions. Overall, the simplified turret only had about three vibration modes affecting tilt, with strong spatial agreement between experimental and FEA modal patterns.

Conference Presentation

(2024) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

Timothy J. Bukowski, R. Mark Rennie, Stanislav Gordeyev, and Matthew Kemnetz "Preliminary aero-mechanical jitter analysis of hemispherical turrets", Proc. SPIE 13149, Unconventional Imaging, Sensing, and Adaptive Optics 2024, 131490E (7 October 2024); https://doi.org/10.1117/12.3028193

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available