August  2006  ARL
January  2007  Quarry
February  2007  la Pilita
March  2007  la Pilita
May  2007  Zacatón
Field Notes
Sunday, February 4 - Sunday, February 11, 2007
Cenote la Pilita, Rancho la Azufrosa, Tamaulipas, Mexico
This trip commences field operations at cenote la Pilita. This 100m deep sink hole boasts 90 degree water, overhanging rock and complex biology. We will run long autonomous missions to map the area and collect novel scientific data.
February 4th, we finishing assembling the vehicle. We also did a preliminary software checkout that revealed some minor wiring mistakes. The rest of the day was spent transporting Clementine to cenoté la Pilita. Rains made the trip a little tricky, but by the end of the day we were prepared to start operations.
With the robot in the water we started testing the basic functionality. Each thruster and sensor was checked in the new environment. We then did a static drop to test the pressure housings and collect data for an initial map. The final activity was to "trim" the vehicle by adjusting weights to make it level and slightly buoyant.
The 7th and 8th were spent debugging. We started driving autonomously and found some problems with the wall following behaviors related to the complex terrain. We also identified hardware and software issues with the science payload and started to characterize its performance. One of those issues was lighting, so we bolted on some dive lights and got good illumination.
The morning of the 8th was spent fixing some cabling issues and getting a group photo. After lunch we tested abort behaviors at a depth of 50 meters. The day culminated with a core sample at depth, we manually fired the instrument and collected some goo.
February 9th was an important day. The day involved more payload debugging, tuning the proximity faults and running short, untethered missions. At one point the tether got snagged and Marcus had to dive. We charged the batteries all afternoon, dialed in a long untethered mission then enjoyed dinner and a movie, followed by some nervous waiting. Around 1:30am Clementine returned; our mission took longer than expected and the executive aborted after 3 hours had elapsed.
Our last day of testing. We continued trying science activities and ran another 3 hour autonomous mission. With yesterday's long run we generated a good map of the cenoté. There were a few interesting bulges however, and with the remaining battery power we sent the vehicle to investigate. Around 6 we finished striking camp and drove the vehicle back to the ranch, to await our return.