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Future plans for planetary exploration currently include using multiple spacecraft to simultaneously explore one planet. This never before encountered situation places new demands on tracking systems used to support navigation. One possible solution to the problem of heavy ground resource conflicts is the use of multi-spacecraft coherent radio metric data, also known as bent-pipe data.
improvements in computational capability and DSN technology have renewed interest in examining the possibility of using one-way Doppler data alone to navigate interplanetary spacecraft. The one-way data can be formulated as the standard difference-count Doppler or as phase measurements, and the data can be received at a single station or differenced if obtained simultaneously at two stations. A covariance analysis is performed which analyzes the accuracy obtainable by combinations of one-way Doppler data and compared with similar results using standard tow-way Doppler and range. The sample interplanetary trajectory used was that of the Mars Pathfinder mission to Mars. It is shown that differenced one-way data is capable of determining the angular position of the spacecraft to fairly high accuracy, but has relatively poor sensitivity to the range. When combined with single station data, the position dispersions are roughly an order of magnitude larger in range and comparable in angular position as compared to dispersions obtained with standard data two-way types. It was also found that the phase formulation is less sensitive to data weight variations and data coverage than the differenced-count Doppler formulation.
The Galileo mission includes an Io flyby, insertion in Jupiter orbit, and ten close satellite flybys at altitudes as low as 250 km. The required orbit determination and navigation are described.
Doppler shift measurements derived from closed-loop radio tracking of distant spacecraft by ground stations of the Deep Space Network (DSN) are one of the principal means used for interplanetary navigation.
The upcoming launch of the solar electric propulsion (SEP) mission New Millennium Deep Space 1 and proposed future SEP missions such as Pluto Express necessitates an analysis of the operational issues related to the navigation of low-thrust missions.
The Deep Space-1 (DS-1) mission to be launched in 1998 will use an autonomous navigation system to guide the spacecraft on a low thrust trajectory to flybys of an asteriod and a comet.
The Global Positioning System (GPS) is widely used for satellite positioning and navigation, and for numerous geolocation activities.
This paper presents covariance and propulsive maneuver analyses performed to determine the impact on navigation performance of parameters such as: the addition of deltaDOR measurements, tracking data schedule, and maneuver execution errors.
This paper discusses the navigation flight experience for the Mars Pathfinder interplanetary cruise.
Navigation of the orbit phase of the Near Earth Asteroid Rendezbous (NEAR) mission will require determination of certain physical parameters describing the size, shape, gravity field, attitude and inertial properties of Eros.
Robust navigation through rocky terrain by small mobile robots is important for maximizing science return from upcoming missions to Mars.
We examine, from a multimission program perspective, key issues and recommended strategies for three aspects of telecommunications and navigation support to future Mars exploration missions.
The new generation of Navigation Doppler Lidar has been designed, developed, and tested for lunar missions. Comprehensive environmental testing is performed to assess the performance of the instrument for upcoming lunar missions and future missions to the Moon and other planetary bodies.
The new generation of Navigation Doppler Lidar has been designed, developed, and tested for lunar missions. Comprehensive environmental testing is performed to assess the performance of the instrument for upcoming lunar missions and future missions to the Moon and other planetary bodies.
This document summarizes and updates the NESC Guidance, Navigation, and Control (GN&C) Technical Discipline Team’s (TDT) work to synthesize and document the current best practices for the design & development of robust and reliable GN&C systems for robotic and crewed (human-rated) spacecraft. These GN&C best practices for future science and exploration missions were derived from the lessons learned, both positive and negative, on earlier spaceflight projects, both robotic and crewed. An attempt has been made to capture preferred practices that reflect the key considerations, trades, and processes directly attributed to past mission success.
Transparent electro-optic (EO) devices can potentially be used for efficient, high speed, and low mass non-mechanical beam steering. Transmission through EO devices will affect the wavefront quality and aberration of both the transmitted and received laser light. The consequences of wavefront distortions on coherent detection are not fully understood. Therefore, we have tested the performance of coherent detection lidar using liquid crystal polarization grating (LCPG) beam steering device. We will discuss the impact of LCPG beam steering devices on the performance of NASA’s Navigation Doppler Lidar, built for providing altitude and vector velocity data to aerial and space vehicles.