Project THOR: Design and Testing of a Full-Scale CCHWD Cryobot
Abstract
Bodies of water on icy Ocean Worlds are prime targets in the search for extant life but accessing and exploring these sub-ice oceans presents many engineering challenges. THOR (Thermal High-voltage Ocean-penetrator Research platform) is a prototype for a new class of Ocean World exploration vehicle which combines elements of an ice-penetrator (cryobot) and an ocean-profiler (sonde). This ice/ocean profiler (IOP) will carry a sampling subsystem and spatial, environmental, and life-detection sensors to characterize the ice and water column. Using the THOR platform and sensor suite we plan to test strategies and behaviors for autonomous exploration and sampling as the vehicle descends through an ice column and into and through a subglacial lake. THOR is funded through the NASA PSTAR program.
THOR builds upon three breakthroughs in cryobot technology produced in the NASA-funded VALKYRIE and SPINDLE projects: onboard closed-cycle hot-water drilling (CCHWD); small-diameter high-voltage, high-power tether technology; and high voltage fluid-resistor water heating. These concepts have been tested only in the lab or in limited field tests. THOR will scale up and integrate these approaches into a high-efficiency cryobot. With hot water jets in the nose and tail, THOR will also be able to melt its way both downwards through ice as well as upwards through the refrozen ice behind it. Onboard servo spoolers will pay out or retrieve power, communications, and strength tethers as the vehicle transits. This bi-directional vertical control will allow THOR to perform autonomously-triggered sonde casts to characterize a sub-ice ocean environment and how it changes over time. Our goal in THOR is to perform a realistic end-to-end systems test of an ocean world concept-of-operations (CONOPS) in a terrestrial analog setting. Using a customized sensor suite and autonomous decision-to-collect algorithms, we will test CONOPS for intelligent IOP exploration and life search strategies for two distinct mission phases: in the ice column and in the sub-ice water column. Here we present the current status of the project, the results of recent design reviews, the results of full scale lab testing of the CCHWD core elements, and plans to test a functional cryobot, operating at 50 kW, on the Matanuska Glacier in June 2020.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.P51B..08S
- Keywords:
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- 0728 Ice shelves;
- CRYOSPHERE;
- 6221 Europa;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6282 Enceladus;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6297 Instruments and techniques;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS