Design of a variable focal length optics for a SWIR Earth observation camera

Abstract: This thesis consists of a preliminary design study of a variable focal length optics for a SWIREarth observation camera which is planned to be placed inside a 6U Cubesat. After thesuccess of DRAGO instrument consisting on a SWIR camera onboard a Cubesat, which hasbeen recently launched (January 2021), the Institute of Astrophysics of the Canary Islands(IAC) began this project with the intention of adding zoom optics to SWIR space imagingsystems. This improvement will add versatility and it will allow changes in the effective fieldof view of the camera, hence achieving a certain magnification to study in more depth anyregion of interest.The main objective of this project is to provide a design solution for the presented challenge,where a mechanism has to displace different groups of lenses following their motion profilesin order to get the desired zoom. During this process different design options were evaluated.The chosen one consist of a ball screw mechanism where the rotation of the screw translatesinto linear displacement of the groups of lenses.The thesis presents a selection of commercial components constituting the mechanism, asone of the objectives of the project was to build a prototype of the mechanism. A structuralanalysis of the structure is done by using ANSYS simulations to ensure the viability of thedesign.