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Young, Brian

Publications and source records attributed to Young, Brian.

27 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

JPL Navigation Support for the JAXA Akatsuki (Planet-C) Return to Venus

This paper details the orbit determination activities undertaken at JPL in support of the Akatsuki (a.k.a. Planet-C) mission’s return to Venus. The JPL navigation team’s role was to provide independent navigation support as a point of comparison with the JAXA generated orbit determination solutions. Topics covered will include a mission and spacecraft overview; small forces modeling; cruise, approach, and Venus phase orbit determination results; and the international teaming arrangement. A discussion of the preparations for the Venus orbit insertion maneuver, which was successfully executed on December 7, 2015, is also covered in detail in the paper.

Young, Brian↗
NASA NTRS2016

MAVEN Transition-To-Science Maneuvers and Comet Siding Spring

After the September 2014 arrival of the Mars Atmosphere Volatile Evolution mission (MAVEN) at Mars, the spacecraft was to perform five maneuvers to reduce the orbit period from 35 to 4.5 hours, and lower the periapsis altitude into the target in-situ science density corridor. While in route, however, the potential threat — and science opportunity — from Comet C/2013 Siding Spring crystallized, and the plan had to be modified to shield the spacecraft behind Mars and support new observations. This paper describes the plan modifications, Monte Carlo analyses necessary to ensure success, and results of executing the modified plan.

Young, Brian↗
NASA NTRS2016

MAVEN Navigation During the First Mars Year of the Science Mission

The Mars Atmosphere and Volatile Evolution mission (MAVEN) is the first mission devoted to studying the Martian atmosphere. From a Navigation perspective it is unique in that science is performed at near aerobraking altitudes. This results in the requirements on Navigation trajectory accuracy requirements which are an order of magnitude tighter than those of aerobraking phases on previous missions. Navigation experiences with the Mars atmosphere are described as they pertain to Navigation models, trajectory reconstructions, trajectory predictions, density corridor control, and collision avoidance of other bodies around Mars.

Demcak, Stuart↗
NASA NTRS2016

Orbit Determination Sensitivity Analysis for the Europa Multiple Flyby Mission Concept

This paper details the results of parametric variations on the notional Europa Mission Concept tour navigation strategy on orbit determination delivery and knowledge errors and the associated statistical ∆V consumption. Approach maneuver placement at encounter minus two and a half days and at encounter minus three and a half days is compared to the reference encounter minus three days location as well as variations to the data cutoff for approach maneuver design, which is baselined one day prior to maneuver execution. An execution error model with fixed and proportional components assigned to the magnitude and pointing directions is applied to each maneuver in a Monte Carlo simulation. Variations on the fixed and proportional contributions to both component errors are simulated and analyzed to show the effect of varying thruster characterization levels. The effects of varying levels of a priori satellite ephemeris errors are also characterized in this study.

Boone, Dylan R.↗
NASA NTRS2013

Transfer Trajectory Design for the Mars Atmosphere and Volatile Evolution (MAVEN) Mission

The Mars Atmosphere and Volatile Evolution (MAVEN) mission will determine the history of the loss of volatiles from the Martian atmosphere from a highly inclined elliptical orbit. MAVEN will launch from Cape Canaveral Air Force Station on an Atlas-V 401 during an extended 36-day launch period opening November 18, 2013. The MAVEN Navigation and Mission Design team performed a Monte Carlo analysis of the Type-II transfer to characterize; dispersions of the arrival B-Plane, trajectory correction maneuvers (TCMs), and the probability of Mars impact. This paper presents detailed analysis of critical MOI event coverage, maneuver constraints, deltaV-99 budgets, and Planetary Protection requirements.

Folta, David↗
NASA NTRS2012

Navigation Challenges in the MAVEN Science Phase

The MAVEN spacecraft will explore Mars' upper atmosphere. The primary science phase will last one (Earth) year, during which the spacecraft will be in an elliptical 4.5 hour orbit at an inclination of 75 degrees. The 75 degree inclination results in the orbit periapsis oscillating between +/-75 degrees latitude, thus naturally covering most Mars latitudes during the primary mission. The orbit will be controlled via maneuvers so that the maximum orbit density remains in a density corridor. This results in the MAVEN science phase being in a light aerobraking type orbit of around 160 km for an extended period. In addition, the mission has significantly less tracking data than aerobraking phases of other missions, and even less than other NASA Mars orbiter primary phases. This results in significant challenges for the Navigation Team. They can be summarized as a difficulty in determining the current density profile, which maps into degraded trajectory predictions and less accurate control over the spacecraft location in the targeted density corridor via maneuvers. This paper describes these challenges and the Navigation Team's plans to meet them.

MAVEN↗