September 29-30, 2004
Guanaco Camp, Atacama Desert, Chile

Agenda
• Repair environmental monitoring station and bring online
• Work on position estimator, power monitoring, and spectrometer
• Set up satellite communication
• Scout field site (Site C)

Status and Progress
Repaired environmental station. Replacement processor board and hard disk for our environmental monitoring station have been installed and rebuilt. We conducted tests of the station’s functionality including measurement of the full solar spectrum with the sun-tracking photospectrometer. All systems are working and we expect to bring everything online tomorrow.

Established power monitoring. We finished modifications to the power monitoring software including calibrating voltage and current sensors and establishing communication the autonomy software. The PMAD is now monitoring voltages and currents throughout the system. These values are being published to the autonomy software for monitoring and fault detection and logged continuously for power and mobility analysis.

Optimized VNIR spectrometer automatically. Zoe’s onboard spectrometer must optimize its detector gains to accommodate changing temperature and signal strength. This routine was the last remaining element in automating control of the device (we had previously been optimizing manually before instrument data collection). Zoe can now power-up, point the foreoptic, optimize the signal levels, and collect spectra. Zoe will now be able to, collect spectra with the same autonomy that it collects images from its SPI cameras.

Refining position estimation. We continue to analyze the performance of our inertial-odometric position orientation system. This system does not use GPS and relies only on measured wheel rotation, rover kinematic models, and inertial sensing. We now believe we have resolved issues with several of the sensors and have high-quality raw data. We have been focusing on timing issues that arise non-deterministically among the many high-rate sampling and estimation threads. The quality of the position and orientation estimates continues to improve as we work to get the best performance out of each cycle. We are now moving to testing with autonomous navigation and having Zoe run around a series of waypoints while it estimates their location and its motions. Zoe has logged many kilometers in the last few days.

Field site scouted. We located a route to transport Zoe from the Guanaco camp to the investigation site (Site C). This region is much different than our two prior investigations in the Coastal Range near Salar Grande. The terrain is a rocky desert of soft soil covered with a desert pavement of rocks. We expect new insights into the performance of the rover and its instruments, and in the significant challenge of detecting life and characterizing habitat in the central desert.

Upcoming
• Conduct autonomous navigation experiments
• Test sun tracking system
• Test Li-Polymer batteries.

Weather
Morning: Clear, cool 14C, no wind, dry
Afternoon: Clear, moderate 22C, no wind except occasional dust devil, humidity 18%
Evening: Clear, cool 16C, no wind, humidity 26%

Quote of the Day
"Well, we should continue."

For more information on Life in the Atacama including images, movies, and field reports see: http://www.frc.ri.cmu.edu/atacama