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Symposia Invited Speakers
SYMPOSIUM 4 SYMPOSIUM 4
ADDRESSING AVIATION AND EDUCATION CHALLENGES WITH TENSEGRITY-CONSTRAINED INFLATABLES: A NEW APPROACH
NASA UNIVERSITY LEADERSHIP INITIATIVE
Jonathan Luntz
Koushik Datta Associate Research Scientist
University Innovation Project Manager Department of Mechanical Engineering
NASA Aeronautics University of Michigan
Abstract Abstract
NASA Aeronautics’ University Leadership Initiative (ULI) provides the Inflatable devices have long been a mainstay in a wide range of
opportunity for university teams to exercise technical and organizational applications, including aerospace, automotive, medical, and sporting
leadership in proposing unique technical challenges, defining goods, due to their low cost, light weight, simplicity, and ability to
interdisciplinary solutions, establishing peer review mechanisms, and compactly stow yet deploy to large sizes with complex shapes. Inflatables,
applying innovative teaming strategies to strengthen the research impact. which generally comprise a statically shaped inflatable bladder, are
This presentation will summarize the goals of ULI and the aeronautics generally lacking in two regards: they do not provide strong structural
research projects awarded under ULI. In particular, it will highlight two of support with selectively tailorable compliance and they cannot be
the awards with adaptive structures research and the system level adjusted in shape once fully inflated. This paper explores a new approach
problems addressed by the research. to enhancing the functionality of inflatables through the use of internal
tensile elements which both constrain the inflatable’s shape as well as
Biography guide its deformation under external forces. By leveraging concepts in the
field of tensegrity mechanisms, tensegrity-constrained inflatables add
Koushik Datta is the University Innovation Project Manager for NASA additional functionality to inflatables. They differ from traditional tensegrity
Aeronautics and manages the University Leadership Initiative and in that the tensegrity mechanism alone does not fully constrain the
University Students Research Challenge. Previously, Koushik was the inflatable except when coupled with the inflatable bladder. Also, in
manager of the LEARN Project and prior to that he was acting Deputy addition to pure tensile segments, multi-segmented tensile elements with
Director for, and helped establish, NASA Aeronautics Research Institute single strings threaded through multiple loops allow structural
(NARI). While at NASA Ames Research Center, Koushik has worked on deformations. This paper is broken into two parts. The first part explores
multiple NASA projects: Lunar Atmosphere and Dust Environment architectures and functionalities provided by tensegrity constrained
Explorer (LADEE), Orion 80-AS Test, Lunar Crater Observation and inflatables. Inflatable devices with controlled compliance are examined
Sensing Satellite (LCROSS), Stratospheric Observatory for Infrared which can be designed with soft compliance or high rigidity in selective
Astronomy (SOFIA), Integrated Vehicle Health Management (IVHM) for the degrees of freedom, and are validated experimentally in the context of
Space Launch Initiative (SLI), and Advanced Air Transportation small deployable user controls (knobs, joysticks, etc.) with different
Technologies (AATT). He has extensive experience in simulation, mechanical feel. Posable tensegrity devices are also explored which rely
modeling and safety-analysis of air traffic systems, science payloads, and on friction between tensile strings and threading loops to enable a user to
space propulsion systems. Koushik received his Ph.D. in Operations apply an external force to reshape and pose the structure. The second
Research from UC Berkeley and B.Tech. in Mechanical Engineering from part describes analytical modeling efforts in two areas: kinematics and
IIT Madras. mechanics. A linear algebraic approach is used to model the small-
deformation kinematics of the tensegrity structure to predict and design
the constrained and allowed degrees of freedom. Graphical kinematic
approaches, adapted from traditional mechanism design, aid in the design
of tensegrity constrained inflatables. An analytical model of the large-
deflection inflation mechanics of cylindrical elastomer bladders is also
presented which enables the prediction and design of axial mode rigidity
of tensegrity constrained inflatables, including enhancement of structural
rigidity through additional circumferential band constraints to inhibit radial
inflation in favor of axial inflation. The set of work presented in this new
field of tensegrity-constrained inflatables provides the foundation for
future exploration and development of a wide class of devices and
application which extend the functionality of inflatables.
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