Summary Report: July 21st 2001 < Back
Devon Island, Nunavut, Canada

- Begin extended sun-synchronous navigation experiment

Summary and Progress
- Began extended experiment. This experiment was intended to stress the
system by increasing the distance, exploring rougher terrain, and
forcing direct conflicts between sun position and goal location. The
plan was to perform a complete circumnavigation of Marine Peak, a
prominent feature at the western extreme of Von Braun Planitia, in
addition to the previously established circuit of the planitia.

- Experienced communication problems. The experiment started minutes
after 3:00pmCDT, difficulty occurred first with problems establishing a
stable communication link with Hyperion and then when the base camp
generator cut out and disabled communication. The latter was quickly
resolved while the former was a problem through much of the night.

- Traversed wet, muddy terrain. In the valley to the south of Marine
Peak, Hyperion encountered mud, snowmelt saturated soil. It traversed
these areas without mechanical difficulty at one half nominal speed.
Occasional false positive obstacles were detected by stereo perception
due to sunlight reflected on pooled water. This necessitated a fall
back from autonomous navigation to safeguarded teleoperation for mud
crossing. The slower speed caused Hyperion to fall behind the scheduled
sun-synchronous route.

- Experienced more communication problems. In the area east of Marine
Peak the radio ethernet antenna and communication bridge failed to
maintain a stable link with Hyperion. (Despite a test the previous
day.) The repeater was moved to several locations before a reliable
link was established.

- Foreshadowing tomorrow's report, more difficulties and delays were
encountered before Hyperion completed the circuit, on schedule with
charged batteries.

- Complete extended sun-synchronous navigation experiment
- Pack and flee

Early: Sunny, no clouds, 12.5C, winds 5-10kph
Late: Sunny, no clouds, 9C, winds 0-5kph.

Quote of the Day
"How can he be so tall and still get lost?"

  ©2001 Carnegie Mellon University - Robotics Institute