DepthX - from Autonomous Underwater Robot Explorer

Ernest Franke¹, Michael Rigney¹, William C. Stone², and Marcus O. Gary^3
1Southwest Research Institute, San Antonio, TX
²Stone Aerospace/PSC Inc., Austin, TX
³The University of Texas, Austin, TX

The DEep Phreatic THermal eXplorer (DepthX) is an autonomous robot developed to investigate and test concepts for exploring liquid water oceans on Europa, the fifth moon of Jupiter. The oceans on Europa are covered by an ice layer several kilometers thick and may have channels or cracks that are much more difficult to explore than large open spaces. The DepthX project was funded by NASA to investigate techniques for a future mission to Europa. Although much of the NASA interest is directed toward the search for life, many of the techniques investigated have applications in exploration for other resources.

The DepthX robot is battery powered with multiple computers dedicated to various tasks. High resolution sonar and inertial sensors are used to map the environment and navigate in confined spaces while learning a safe return path. Water chemistry sensors measure temperature, pH, salinity, sulphide, and conductivity to identify locations where energy gradients may support life. When such a location is found, the robot can maneuver near the wall, capture images from two video cameras and use image analysis to identify significant visual patterns. A video microscope searches for microbial activity. The DepthX robot also includes a probe arm that can be extended to a wall and a solid sampler to capture core samples at locations identified by software algorithms for return and analysis.

Autonomous operation of the DepthX robot was tested at Sistema Zacatón, near Tampico, Mexico in May, 2007. The robot successfully explored cenote Zacatón to a depth of 1100 feet, mapping the cave walls and returning samples.

AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas