Engineering topics
Stumpf, Paul
Publications and source records attributed to Stumpf, Paul.
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.
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.
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.
MAVEN Navigation During the First Mars Year of the Science Mission
No abstract available
Cassini Maneuver Experience Through the Last Icy Satellite Targeted Flybys of the Mission
No abstract available
Cassini Maneuver Experience for the Fourth Year of the Solstice Mission
After sixteen years of successful mission operations and invaluable scientific discoveries, the Cassini orbiter continues to tour Saturn on the most complex gravity-assist trajectory ever flown. To ensure that the end-of-mission target of September 2017 is achieved, propellant preservation is highly prioritized over maneuver cycle minimization. Thus, the maneuver decision process, which includes determining whether a maneuver is performed or canceled, designing a targeting strategy and selecting the engine for execution, is being continuously re-evaluated. This paper summarizes the maneuver experience throughout the fourth year of the Solstice Mission highlighting 27 maneuvers targeted to nine Titan flybys.
Cassini-Huygens maneuver automation for navigation
Many times during the Cassini-Huygens mission to Saturn, propulsive maneuvers must be spaced so closely together that there isn't enough time or workforce to execute the maneuver-related software manually, one subsystem at a time. Automation is required. Automating the maneuver design process has involved close cooperation between teams. We present the contribution from the Navigation system. In scope, this includes trajectory propagation and search, generation of ephemerides, general tasks such as email notification and file transfer, and presentation materials. The software has been used to help understand maneuver optimization results, Huygens probe delivery statistics, and Saturn ring-plane crossing geometry. The Maneuver Automation Software (MAS), developed for the Cassini-Huygens program enables frequent maneuvers by handling mundane tasks such as creation of deliverable files, file delivery, generation and transmission of email announcements, generation of presentation material and other supporting documentation. By hand, these tasks took up hours, if not days, of work for each maneuver. Automated, these tasks may be completed in under an hour. During the cruise trajectory the spacing of maneuvers was such that development of a maneuver design could span about a month, involving several other processes in addition to that described, above. Often, about the last five days of this process covered the generation of a final design using an updated orbit-determination estimate. To support the tour trajectory, the orbit determination data cut-off of five days before the maneuver needed to be reduced to approximately one day and the whole maneuver development process needed to be reduced to less than a week..