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This paper surveys key progress in sensors, algorithms, and processors that has alleviated these specific barriers, thereby enabling practical autonomous navigation.
This paper describes navigation results obtained in the field tests and shows that accurated heading estimation provides a significant improvement over previous results.
A description is given of the operational JPL project to measure, combine, and predict Earth rotation parameters in support of spacecraft navigation.
Several options are being examined to reduce the costs of spacecraft and deep space missions. One such option is to fly spacecraft in a non-coherent mode, that is, the spacecraft does not carry a transponder and cannot coherently return a Doppler signal. Historically, such one-way data has not been used as the sole data type due to the instability of the onboard oscillator, the use of S-band frequencies, and the corresponding larger error sources which could not be modeled. However, with the advent of high-speed work stations and more sophisticated modeling ability, the possibility of using one-way data is being re-examined. This paper addresses the navigation performance of various one-way data types for use in interplanetary missions.
This paper provides an in-depth review of the Mars Observer Navigation Team's activities throughout interplanetary cruise to Mars and our response to the spacecraft's anomaly which occurred approximately 68 hours before encounter.
We investigate the application of conditional sequencing to robot navigation.
Developing cost efficient individual flight projects that perform both orbital and surface exploraton will likely require intelligent infrastructure elements for critical functions such as navigation.
Recent scientific discoveries at Mars have heralded an unprecedented commitment and focus by NASA and its international partners toward further exploration of Mars. As part of this effort NASA has an on-going project, called the Mars Network, to examine communication and navigation infrastructure requirements needed to support Mars exploration.
This chapter describes fundamental research aimed at achieving such long-term objectives through application of soft computing techniques for safe and reliable autonomous rover navigation.
The Galileo spacecraft's navigation results for the first eleve Jupiter satellite encounters are described.
The impact of using altimeter range measurements as an observation type for navigation of spacecraft about small bodies is evaluated.
This paper describes preliminary navigation analyses for the proposed Europa Orbiter mission.
In this paper we describe the hardware design, the control and navigation system, and our preliminary experiments with the robotic wheelchair MAid (Mobility Aid for Elderly and Disabled People).
This paper presents an investigation of the navigation accuracy that can be achieved with two-way coherent X-band Doppler phase and frequency data; both theoretical and practical aspects of the two Doppler formulations are addressed.
Reliable detection of non-traversable hazards is a key requirement for off-road autonomous navigation. A detailed description of each obstacle detection algorithm and their performance on the surveyed obstacle course is presented in this paper.
There are three primary drivers behind current investments in telecommunications information technology and navigation. One is finding ways to maximize the volume of science data returned from missions since i nstrument data generation often exceeds communication bandwidth. Another is to provide the necessary technology to enable networked spacecraft around Mars. The third driver is to enable more precise landing so in-situ vehicles can be placed in the more scientifically interesting regions. This paper describes the current NASA investments in these areas funded through the NASA Mars Technology Base Program NRA.
Autonomous off-road navigation of robotic ground vehicles has important applications on Earth and in space exploration. Progress in this domain has been retarded by the limited lookahead range of 3-D sensors and by the difficulty of preprogramming systems to understand the traversability of the wide variety of terrain they can encounter.
The 2001 Mars Odyssey Mission has returned an orbiter to map the planet and search for water. The success of this mission has reestablished confidence in Mars exploration that will pave the way for future orbiters, landers, adn rovers. The spacecraft has completed its journey and is now in the orbital science-gathering phase of the primary mission, which will continue through August 2004. This paper will describe teh strategy that was designed to safely and accurately navigate the spacecraft to Mars, and also relate the in-flight experience.