(Georgia Institute of Technology, 2012-06)
Korzun, Ashley M.; Braun, Robert D.
Supersonic retropropulsion is an entry, descent, and landing
technology applicable to and potentially enabling the
high-mass missions to the surface required for advanced
robotic and human exploration at Mars. For conceptual
design, an initial understanding of the significance
of retropropulsion configuration on the vehicle’s static
aerodynamic characteristics and the relation of this configuration
to other vehicle performance metrics that traditionally
determine vehicle configuration is necessary.
This work develops an approximate model for the aerodynamic
- propulsive flow interaction based on momentum
transfer within the flowfield and the geometry of relevant
flow structures. This model is used to explore the impact
of operating conditions, required propulsion system performance,
propulsion system composition, and vehicle
configuration on the integrated aerodynamic drag characteristics
of full-scale vehicles for Mars entry, descent,
and landing. Conclusions are then drawn on the fidelity
and effort required to support specific design trades for
supersonic retropropulsion.
(Georgia Institute of Technology, 2011-06)
Post, Ethan A.; Dupzyk, Ian C.; Korzun, Ashley M.; Dyakonov, Artem A.; Tanimoto, Rebekah L.; Edquist, Karl T.
NASA’s Exploration Technology Development and
Demonstration Program has proposed plans for a series
of three sub-scale flight tests at Earth for supersonic
retropropulsion, a candidate decelerator technology for
future, high-mass Mars missions. The first flight test
in this series is intended to be a proof-of-concept test,
demonstrating successful initiation and operation of
supersonic retropropulsion at conditions that replicate
the relevant physics of the aerodynamic-propulsive
interactions expected in flight. Five sub-scale flight test
article concepts, each designed for launch on
sounding rockets, have been developed in
consideration of this proof-of-concept flight test.
Commercial, off-the-shelf components are utilized as
much as possible in each concept. The design merits
of the concepts are compared along with their predicted
performance for a baseline trajectory. The results of a
packaging study and performance-based trade studies
indicate that a sounding rocket is a viable launch
platform for this proof-of-concept test of supersonic
retropropulsion.
(Georgia Institute of Technology, 2008-06)
Korzun, Ashley M.; Smith, Brandon P.; Hartzell, Christine M.; Yu, Chi-Yau; Place, Laura A.; Martinelli, Scott K.; Braun, Robert D.; Hott, Kyle B.
Execution of a full entry, descent, and landing (EDL) from low Earth orbit is a rare requirement among university class spacecraft. Successful completion of the Mars Gravity Biosatellite mission requires the recovery of a
mammalian payload for post-flight analysis of the effects of partial gravity. The EDL design for the Mars Gravity
Biosatellite is driven by requirements on the allowable deceleration profile for a payload of deconditioned mice and
maximum allowable recovery time. The 260 kg entry vehicle follows a ballistic trajectory from low Earth orbit to a
target recovery site at the Utah Test and Training Range. Reflecting an emphasis on design simplicity and the use of
heritage technology, the entry vehicle uses the Discoverer aeroshell geometry and leverages aerodynamic
decelerators for mid-air recovery and operations originally developed for the Genesis mission. This paper presents
the student-developed EDL design for the Mars Gravity Biosatellite, with emphasis on trajectory design, dispersion
analysis, and mechanical design and performance analysis of the thermal protection and parachute systems. Also
included is discussion on EDL event sequencing and triggers, the de-orbit of the spacecraft bus, plans for further
work, and the educational impact of the Mars Gravity Biosatellite program.