Principal Investigators
Don George
Patrick Phelan
Clark Schiferl
Inclusive Dates 
06/03/2024 to 12/03/2024

Background 

Several Divisions of SwRI are developing numerous Lunar instruments through multiple NASA and SwRI internal research (IR) projects, however we currently have no stand-alone platform on which they can be deployed. This forces us to rely on other institutions to provide the bulk of the hardware for this type of science mission, and thus receive the bulk of the funding. The solution to this lack of a platform is the creation of the SwRI Lunar Surface Observatory (SwRI LSO). 

This presidential discretion (PD) internal research project was initiated to create new devices, associated skills and systems that make the SwRI Lunar Surface Observatory (SwRI LSO) “proposal ready” for the upcoming Artemis IV opportunity and beyond. The LSO and/or subsections of it will be proposed for three current NASA proposals associated with the Artemis IV, Artemis V, and the SALSA CLPS program. This PDIR addresses nine key aspects of the SwRI LSO including power, thermal control, physical design, and communications. The highest priority of these are the three research-objectives related to thermal control. We have divided the project into two phases, Phase One addresses a review of the PDIR scope including supported payloads, materials selection, power options, and thermal approach including survive-the-night or operate-thru-the-night options. It also addresses a Top-Level Design and three critical research activities for thermal control. Phase Two will address additional developmental objectives including raising the SwRI LSO to TRL 6. Through this two-phase implementation of technical objectives, this PDIR will create the critical technologies required to propose the SwRI LSO for stand-alone ADI’s, CLPS Landers, and Luner Terrain Vehicles. Having the SwRI LSO will position the SwRI Space Sector to answer fast turn-around calls for stand-alone ADI’s as well as support calls for lander and vehicle mounted instruments. 

Approach 

Phase one research objectives: 

  1. Using expertise across the Institute, phase one was expanded to include a ‘scoping’ task consisting of reviews, discussion, and trades of available technologies and capabilities applicable to the LSO concept.
  2. Generate a Top-Level Design and documents for the SwRI LSO.
  3. Create an electrically controllable Thermal Isolation Switch (TIS). This is expected to be a patentable device. Prototypes will be built and tested.
  4. Create a cryogenic Thermal Isolation Enclosure (TIE) needed to survive a Lunar night. A full-scale mock-up will be built.
  5. Create a Thermal and Battery Management (TBM) approach and system also needed to survive a Lunar night. System design will be validated via simulation.

Phase two development objectives:

  1. Generate a Top-Level Design and documents for the SwRI LSO.
  2. Design a Direct to Earth (DTE) communications system.
  3. Design Solar Panels for use in modular arrays and identify potential vendors.
  4. Design Astronaut Accommodations meeting NASA carry requirements.
  5. Update SwRI Spacecraft Avionics Core to survive the Lunar environment. 

Accomplishments 

At present we are functionally about two months into the performance of this PDIR. We have held several focused discussions and performed testing on the baseline TIS resulting in some changes to our approach in the SwRI LSO design. 

  • Discussions have ruled out the use of Phase Change Materials for general use in support of the survive-the-night capability.
  • Testing has shown that the NITENOL Belville Washers cannot easily produce an electrically reversable thermal switch. Other configurations are being pursued and will be tested.
  • Discussions have proposed that the SwRI LSO can use a Water Cycle Based Thermal Engine to provide enough thermal and electrical energy to not only survive-the-night, but to operate-thru-the-night. During the Lunar Day, using electrolysis powered by the solar arrays, the SwRI LSO will convert about 240 grams of water into pressurized H2 and O2. Then during the Lunar Night, the SwRI LSO will convert the gasses back to water using a Fuel Cell. This conversion will produce 4W thermal and 5W electrical power. This will in turn keep the LSO warm throughout the night and provide electricity to recharge batteries and allow for operation of an instrument during the night. This will not be ready for the current round of proposals; however, we already have a battery solution that closes, allowing us to survive-the-night for an Artemis IV Astronaut Deployed Instrument (A4DI) and operate-thru-the-night for a Lunar Terrain Vehicle Instrument (LTVI).
  • Discussions have provided a path to a Dust Mitigation Strategy using a simple, ceramic break, cover to seal instruments during travel and a heritage door to cover the instrument aperture during times of dust disturbances in the vicinity. While this is not specifically for the LSO it is for its first planned payload and came up during discussions. 

Additional discussions will be held in the upcoming quarter as well as design and testing activities for the top-level design, thermal switch, thermal enclosure and thermal and battery management subsystem. After results of Phase One will determine how to proceed with Phase Two in a gate review held after completion of Phase One. ACR leadership will advise us if the Thermal Engine (fuel cell) development will take place under this PDIR or another IRD vehicle.