Abstract
For balloon-borne telescopes, the primary mirror is the most important optical element, but designing a primary mirror with an excellent overall performance is a challenge. To comprehensively consider the contradictory objectives of the root mean square (RMS) surface error under gravity in the X and Z directions, the mass and fundamental frequency of the primary mirror, a parametric primary mirror design using the compromise programming method based on topology optimization is proposed. The parametric design of the compromise programming method based on topology optimization is used to find the optimal solution for X-direction RMS (RMSx), Z-direction RMS (RMSz), mass, and fundamental frequency. Compared with the initial primary mirror structure designed according to traditional experience, the overall performance is improved. Results show that the respective mass of the primary mirror, the RMSx and the RMSz decreased by 8.5%, 14.3% and 10.5% compared to those before optimization. Comprehensive consideration can prove the effectiveness of parametric design based on the topology optimization of the primary mirror. This method provides a reference for the design of other primary mirrors for balloon-borne telescope and space cameras.
Highlights
Near-space, called suborbital space, is the airspace 20–100 km away from the Earth’s surface [1,2]
The parametric design method of the primary mirror based on topology optimization is proposed
The topology optimization of the primary mirror was used as the basis for grouping lightweight ribs
Summary
Near-space, called suborbital space, is the airspace 20–100 km away from the Earth’s surface [1,2]. Park et al made a topology optimization design for the primary mirror by considering the gravity in the optical axis direction and the polishing stress, achieving an RMS with a better performance than that of the traditional hexagonal lightweight structure [10]. The topology and parametric-optimization-based lightweight design of a space reflective mirror were studied by Liu et al [14]. The parametric design of the primary mirror using the compromise programming method based on topology optimization is presented. The mass and RMSz of the primary mirror after parametric design were improved compared with those of the initial structure This optimization method can solve the contradictory multi-objective problem. The aperture of the primary mirror is 800 mm, and the radius of curvature is 2800 mm [18]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.