One conclusion from the S2024 Internal Design Review is that more time is required in order to advance to Phase C. The following plan forward is suggested in order to be ready for the next Critical Design Review in May 2025.
Many experts and advisors have suggested that it would be practical to pursue a (simpler) experimental prototype alongside the development of the actual space payload. This motivates the development of a demonstrator model visible-range hyperspectral imager that would allow our team to encounter “all mistakes” in a lower-cost, lower-stakes environment. The design of the FINCH EYE SWIR hyperspectral imager will take place concurrently and be informed by our findings with the demonstrator model.
A chronology with the demonstrator model, and subsequently the FINCH EYE payload, is proposed:
| BUILD I | →Visible range optical breadboard model consisting of a monochrome CMOS camera and a standard machine vision camera lens. Will use a transmission grating as the dispersive element. Reference designs available (HYPSO-1).
→Complete a design and analysis of the hyperspectral imager in ZEMAX. An analytical design framework which maps performance specifications to design parameters should be presented. A ZEMAX model of this design will be made, and a tolerance analysis will be performed. The design will be exported to Pay-Mech.
→Practice optical alignment and spectral characterization, teach new members how to properly handle optical components. Assess spatial and spectral resolution and conduct “functional” tests which will gather “live” data. | | --- | --- | | BUILD II | →Co-develop optomechanical housing for BUILD I, carefully considering assembly and alignment aspects. Mostly Pay-Mech.
→Integrate optical components with optomechanical housing in the laminar flow hood workspace. Assess quality of assembly by repeating the characterization tests.
→Conduct other more sophisticated analyses as needed. | | BUILD III | Same as BUILD I but for SWIR design: GRISM, FLIR TAU, Objective Lens.
Selection: Shortlist several candidates, obtain quotes and information from suppliers. Design: perform design calculations on the basis of Build I framework using shortlisted components. Implement all critical elements in ZEMAX (grism, foreoptic), validate performance in ZEMAX model. (Difficult) To Pay-Mech: tolerance analysis and opto-mechanical specifications (element dimensions, positions, tolerances). | | BUILD IV | Same as BUILD II but for SWIR design: GRISM, FLIR TAU, Objective Lens. |
Concerning the timeline, the aim is to complete Build I before the end of the Fall 2024 semester, so that Pay-Mech could submit their opto-mechanical design to fabrication around winter holidays. We would like to present our results on designing, assembling, and testing to advisors in a dedicated review session in Winter 2025, and also gather feedback from them on our Build III ZEMAX model. The following timeline for the next 12 months is proposed:
| SEPTEMBER 2024 | • Onboarding, re-engage continuing members |
|---|---|
| OCTOBER 2024 | • Complete Build I design calculations |
| • Order components for Build I (lab demonstrator) | |
| • Complete Build I ZEMAX model | |
| • Finish test plans (and purchase components for them) | |
| • export opto-mechanical specification model to Pay-Mech |
• Continue research components for Build III • Continue discussions with Wasatch Re: Grism | | NOVEMBER 2024 | • Assemble Build I on optical breadboard • Conduct alignment, characterization, and functional tests • Solicit feedback from Dr. Chen regarding assembly and mechanical design — milestone: finish and present Build I
• Build III: engage with G&H, Optec, Resolve Optics, Hyperion — dependency: need expected temperature range of payload | | DECEMBER 2024 | • Deadline: Finalize opto-mechanical specifications (dimensions of components, positions, tolerances) together w/ Pay-mech • Deadline: Submit Abstract for SmallSat Europe 2025 | | JANUARY 2025 | • Perform design calculations for Build III • Begin ZEMAX model of Build III, using components found in November • Continue to engage in supplier discussions if need be • Support design & fabrication of Build II optomechanical housing | | FEBRUARY 2025 | • Assemble Build II, conduct testing • Review design of Build III with Dr. Chen during reading week. — milestone: finish and present Build II
• Review assembly of Build II, ponder assembly strategy for Build III. • Solicit feedback on ZEMAX model and design calculations of Build III • Conduct tolerance analysis etc. for Build III. | | MARCH 2025 | • Incorporate feedback on design & ZEMAX model of Build III • Finalize tolerance analysis, etc. • Deadline: finalize & deliver opto-mechanical specifications for Pay-Mech | | APRIL 2025 | • Work on paper for SmallSat Europe • Continue running analysis on design (thermal, stray light, etc.) • Prepare CDR presentation. | | MAY 2025 | • Deadline: Deliver CDR presentation and submit paper for SmallSat Europe 2025 | | JUNE 2025 - AUGUST 2025 | May-August: buffer to finish this ambitions program. We will be able to resolve system-wide concerns and address feedback from advisors during Summer 2025.
| | SEPTEMBER 2025 | Be ready to initiate purchase of space-ready components. Pay-Mech will be ready to initiate fabrication of housing. |
By the end of Phase C, we are supposed to deliver a design of the SWIR space-ready payload. This requires having the following:
These qualitative goals can be achieved by following the roadmap proposed herein and achieving a successful outcome. In other words, we cannot exit Phase C without completing...