Summary Report: July 18th 2001 < Back
Devon Island, Nunavut, Canada

- Begin 24-hour sun-synchronous navigation experiment

Status and Progress
- Began 24-hour sun-synchronous navigation experiment. The purpose of
the integrated experiment is measure and analyze the performance of the
Hyperion system including its ability to manage its power resources
(input and output) by sun-synchrony and its ability to navigate a path
through planetary-analog terrain while following a sun-synchronous
mission plan. The experiment began at 7:30amCDT at a location on Von
Braun Planitia northeast of the base camp. Throughout the day Hyperion
made its way northwest.

- Followed sun-synchronous plan. The sun-synchronous planner, named
Tempest (temporal mission planner for the exploration of shadowed
terrain), determined the optimal starting location and time for
circumnavigate Von Braun Planitia and visit 19 designated waypoints.
Hyperion executed the plan navigating autonomously between waypoints.
This experiment was planned with ample speed margin (average plan speed
7.5cm/sec versus Hyperion maximum speed 30cm/sec) and the planner was
allowed to stop and recharge batteries from solar energy if desired. By
midnight Hyperion was running right on schedule with batteries
well-charged for continuing operation.

- Navigated rough terrain. The stereo perception system and terrain
navigator performed impressively. (See attached for one of many
examples of autonomous navigation through a rock field.) There were no
instances where the laser scanner triggered on an obstacle that the
perception system missed. The navigator found, sometimes very
circuitous by necessity, through rough terrain. Hyperion autonomously
crossed one stream and climbed a snowfield (texture was sufficient for
stereo perception).

- Teleoperated rarely. In a few rare instances Hyperion's health
monitor indicated the robot had reached an impasse and stopped to await
instructions. Hyperion does not currently back up autonomously so
teleoperation from the base camp is used to back up and/or reorient
before re-engaging autonomous navigation. This amounted to a few tens
of meters of the thousands traveled (exact statistics still to be computed).

- Withstood substantial winds. Near midnight Hyperion traversed a
ridgeline, panels facing the sun and with steady wind (15-20kph) with
gusts (maximum 27kph) from the north. As a safety precaution field
observers walked immediately behind Hyperion but did not influence its
behavior. Ultimately Hyperion remained stable in the wind and no
intervention was required.

- Logged complete telemetry and key image sequences during the
experiment for later analysis of power and navigation performance.

- Complete sun-synchronous navigation experiment

Early: Sunny. No clouds. High 13C. Winds 5-10kph.
Late: Sunny. Widely scattered high clouds (<5%). Low 8C. Winds 15-25kph.

Quote of the Day
"It's all good. Go to sleep."

  ©2001 Carnegie Mellon University - Robotics Institute