The objective of this research is to discover, express, and exhibit the importance of reasoning about sunlight as it pertains to robotic exploration.
We are developing sun-cognizant path and temporal planning software for rovers to dodge shadows, seek sun, and drive sun-synchronous routes. This requires planning capable of autonomous navigation in partially known, time-varying environments with additional considerations of power and thermal management.
We are investigating algorithms that incorporate scheduling and temporal reasoning, modeling of light and ephemeris with autonomous navigation.
We are prototyping a robot, named Hyperion, to exploit the advantages and meet the challenges of sun-synchrony. We have conceived Hyperion as a vehicle physically capable of speeds of about 1/2 meter per second at a maximum locomotive power consumption of 150W. It has a wheel-base of approximately 2 meters by 2 meters to provide stable support for its 3 square meter, vertically mounted solar panel. The vehicle and power system have mass of approximately 70 kilograms with the sensors, electronics and computing payload adding 50 kilograms and a steady power consumption of 90W. Design refinements and component tests are currently underway.
We intend a field experiment in a polar planetary-analog setting in a location of continual direct sunlight. We will collaborate with the NASA Haughton-Mars Project and conduct experiments on Devon Island, Nunavut, Canada in July 2001. Our aim is to verify the algorithms for combining sun-seeking with autonomous navigation and to validate the parameters that will allow sun-synchronous explorers to be scaled for other planetary bodies. The viability of sun-synchronous circumnavigation is dependant upon parameters such as planet diameter, axial tilt, rotation period, surface gravity, and solar irradiance.
We will scale and generalize results of studies and Earth-bound experiments to other planetary bodies.