Description

The goal of this trade is to determine which location to do Systems Level TVAC Testing. TVAC testing is expected to be conducted no earlier than May 2024. Since TVAC is expected to be a large cost, it is important for us to determine a feasible location early so we can budget for it.

TVAC for FINCH is expected to run for 8 cycles, with a maximum temperature of 75°C and a minimum of -40°C. The first revision of the test plan can be found here.

This trade affects systems, thermal, optics, electrical, mechanical, and systems. Requirements for TVAC selection are outlined in the following section. This trade will be completed by Thermal, reviewed at a Systems’ Meeting, and finalized pending approval from subsystems.

Requirements

Identify the key requirements that will be used to evaluate and compare the different options being considered and how they will be weighed against one another. These criteria might include factors such as cost, performance, schedule, risk, and other relevant considerations.

The key requirements that will be used to compare the different TVAC providers are as follows:

• Temperature Range: the TVAC chamber shall be able to consistently reach temperatures of +75°C to -40°C

• Ramp Rate: The TVAC Chamber shall be able to achieve a ramp rate of 2.5°C/min

• Pressure: the TVAC chamber shall be able to consistently reach a pressure of at 1E-5 Torr

  • Payload Plan needs 1E-5 Torr but NASA GEVS recommends 1E-4 Torr

    • Update: NASA GEVS specifies 1E-5 Torr for the tests Payload wants to conduct (NASA GSFC-STD-7000, section 2.6.2.4d)

    

• Presence of an Optical Port: the TVAC chamber shall have an optical port.

  • QUESTION: how big should it be?
    • TBD based on Diameter of fore optics (estimated to be on the order of ~5cm)

• Radiative Shroud: The TVAC Chamber should have a radiative shroud for accurate heat transfer

• Cost: lower is better :)

Options

Present a summary of the options being considered, along with their key characteristics and potential impacts. This might include information on costs, performance, schedule, risk, and other relevant factors.

**MDA —**

Temperature Range: Satisfied (they can go well beyond what FINCH TVAC requires)

Ramp Rate: Satisfied

Pressure Range: Satisfied (they can go well beyond what FINCH TVAC requires)