William Whittaker

Self-Driving Cars and the Urban Challenge

Self-driving cars have been a dream as long automobiles have existed. The automobile is ubiquitous in the developed world and is becoming so in the developing world. In 2007, the worlds two largest automakers sold over 18 million vehicles worldwide. As we consider domains to which we can apply intelligent systems, the automotive industry stands out as having the most potential for impact.

Preliminary Results on the use of Stereo, Color Cameras and Laser Sensors in Antarctica

In November of 1998, an expedition from Carnegie Mellon University travelled to the Patriot Hills, Antarctica. The purpose of the expedition was to demonstrate autonomous navigation and robotic classification of meteorites and the characterization of various robotics technologies in a harsh, polar setting. This paper presents early results of experiments performed on this expedition with CCD cameras and laser range finders. It evaluates the ability of these sensors to characterize polar terrain. The effect of weather on this characterization is also analyzed. The paper concludes with a discussion on the suitability of these sensors for Antarctic mobile robots.

Mission planning for the Sun-Synchronous Navigation Field Experiment

Describes TEMPEST, a planner that enables a solar-powered rover to reason about path selection and event placement in terms of available solar energy and anticipated power draw. Unlike previous path planners, TEMPEST solves the coupled path, path timing and resource management problem. It combines information about mission objectives, operational constraints, the planetary environment and rover performance, and employs the Incremental Search Engine, a search algorithm that produces optimal paths through high-dimensional spaces. In July 2001, TEMPEST supported the Sun-Synchronous Navigation Field Experiment on Devon Island in the Canadian Arctic. The planner successfully selected time-sequenced, closed-circuit paths that enabled a solar-powered planetary rover prototype to traverse a multi-kilometer path over 24 hours with battery energy reserve. The field trial results motivate future work in mission re-planning, multiple resource constraint analysis and improved speed and memory performance. Our objective is to fulfill a need for resource-cognizant autonomy that is critical for future long-distance planetary surface missions.

A Concept for Robotic Lunar South Pole Exploration

The lunar south pole region may contain frozen volatiles such as water and carbon dioxide in surface depressions which are permanently dark. The low Sun angles of the region create these permanently dark areas and also provide nearby regions of long term sunlight and moderate temperatures which benefit robotic exploration. In this paper a concept for a robotic explorer named Icebreaker is presented. It is designed to take advantage of the south pole environment and to find and analyze frozen volatiles. Icebreaker is an innovative new spacecraft concept which combines the functionality of traditional landing craft and mobile robots into one integrated vehicle. This type of vehicle will allow larger science packages to be delivered to the planets. Icebreaker will acquire samples with a drill and determine the presence and composition of volatiles inside cold traps using a Regolith Evolved Gas Analyzer (REGA).

Steering and control of a passively articulated robot

The need for light weight yet highly mobile robotic platforms is driven by the limitation of available power. With unlimited energy, surface exploration missions could survive for months or years and greatly exceed their current productivity. The Sun-Synchronous Navigation project is developing long-duration solar-powered robot exploration through research in planning techniques and low-mass robot configurations. Hyperion is a rover designed and built for experiments in sun-synchronous exploration. This paper details Hyperions steering mechanism and control, which features 4-wheel independent drive and an innovative passively articulated steering joint for locomotion.