A method has been developed for caging science instrumentation to protect from pyro-shock and EDL (entry, descent, and landing) acceleration damage. Caging can be achieved by immersing the instrument (or its critical parts) in a liquid and solidifying the liquid by cooling. After the launch shock and/or after the payload has landed, the solid is heated up and evaporated.
In the example of a sensitive x–y seismometer, the volume is filled with CO2 (at an elevated pressure), or other compatible liquid. Then the liquid is frozen and maintained at a temperature below –80 °C for the duration of the flight. The solid is then allowed to sublime through a valved port. Other uses include caging of drag-free elements of LISA (laser interferometer space antenna) spacecraft and their progeny, caging instrumentation and avionics for penetrator missions, and caging of electronics to survive launch shock.
This work was done by Konstantin Penanen and Talso C. Chui of Caltech for NASA’s Jet Propulsion Laboratory. For more information, download the Technical Support Package (free white paper) at www.techbriefs.com/tsp under the Physical Sciences category. NPO-46930
This Brief includes a Technical Support Package (TSP).
Cryogenic Caging for Science Instrumentation
(reference NPO-46930) is currently available for download from the TSP library.
Don't have an account?
Overview
The document titled "Cryogenic Caging for Science Instrumentation" discusses innovative methods for protecting sensitive spacecraft instruments during launch and entry, descent, and landing (EDL) phases. Authored by Konstantin Penanen and Talso Chui, it addresses the challenges mechanical engineers face in designing effective caging mechanisms that can withstand the significant forces experienced during these phases.
Traditionally, rigid caging solutions have relied on complex actuators, such as gas-driven or paraffin bellows, which add weight and consume power. The proposed solution in this document is to utilize cryogenic techniques, specifically by immersing instruments or their critical components in a liquid that can be solidified through cooling. This method simplifies the caging process and reduces the overall mass and power requirements.
One notable implementation example provided is the caging of lunar or Mars seismometers. The document describes a sensitive x-y seismometer designed for geoplanetary studies, which is particularly vulnerable to damage from launch shocks and EDL accelerations. The proposed method involves filling the seismometer's volume with CO2 (or another compatible liquid) at elevated pressure, then freezing it to maintain a temperature below -80°C during the flight. After the mission, the solid CO2 can be sublimated through a valved port, allowing the instrument to function normally.
The document also outlines other potential applications for this cryogenic caging technique, including the protection of drag-free elements in the LISA spacecraft, instrumentation and avionics for penetrator missions, and electronics designed to survive launch shocks.
Overall, the cryogenic caging method presents a promising alternative to traditional mechanical solutions, offering a more efficient and effective way to safeguard sensitive scientific instruments in the harsh conditions of space travel. The document emphasizes the broader technological, scientific, and commercial implications of this approach, suggesting that it could lead to advancements in various aerospace-related fields.
For further inquiries or assistance regarding this technology, the document provides contact information for the Innovative Technology Assets Management at NASA's Jet Propulsion Laboratory.
