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We investigate the controllability of an origami system composed of Miura-ori cells. A substantial volume of research on folding architecture, kinematic behavior, and actuation techniques of origami structures has been conducted. However, understanding their transient dynamics and constructing control models remains a formidable task, primarily due to their innate flexibility and compliance. In light of this challenge, we discretize the origami system into a network composed of interconnected particle masses alongside bar and hinge elements. This yields a state-space representation of the system's dynamics, enabling us to obtain the system's controllability attributes. Informed by this computational framework, we explore the controllability Gramian-based method for finding the most efficient crease line for Miura-ori cell deployment using an actuator. We demonstrate that the deployment efficiency guided by this theoretical method agrees with the empirical results obtained from the energy consumption to deploy the origami structure. This investigation paves the way toward designing and operating an efficient the complex actuation system for origami tessellations.
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ADAPTIVE NET RADIATIVE HEAT TRANSFER AND THERMAL MANAGEMENT WITH ORIGAMI-STRUCTURED SURFACES
The ability to control radiative behavior through the angular positioning of structured surfaces (e.g. the cavity effect) offers the ability to provide thermal management in dynamic radiative environments. Structures comprised of origami tessellations offer a means to achieve angular cavities that approach black-like behavior during collapse by exploiting use of the cavity effect. Expanded origami surfaces exhibit intrinsic radiative properties while collapsed surfaces exhibit increasingly black-like behavior as the cavity aspect ratio increases. Actuation of such surfaces provides the means to achieve any apparent radiative behavior between these two extremes. This work explores the use of three origami structures (finite V-groove, hinged V-groove and Miura-ori) and their respective apparent radiative properties as a function of cavity geometry using Monte Carlo ray tracing. Results are presented as a function of tessellation geometry and degree of actuation (i.e. collapse). Ray tracing models are benchmarked with V-groove geometries for which analytical models exist in the literature. Convergence for ray independence was determined to be satisfactory when the standard error of the mean for every test case was less than 0.005. Deviation in the apparent absorptivity for finite V-groove relative to the infinite V-groove is quantified. The apparent absorptivity of the Miura-ori fold exhibits sensitivity to the fold geometry when the angle of the unit cell is varied, but is relatively insensitive to the length ratio of the panel. The variable nature of the net radiative heat transfer, achievable through actuation, affords a method for thermal management of components with variable heat dissipation and/or variable radiative environments.
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- Award ID(s):
- 1749395
- PAR ID:
- 10084752
- Date Published:
- Journal Name:
- 16th International Heat Transfer Conference, Beijing, China
- Page Range / eLocation ID:
- 8405-8413
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1615/IHTC16.rti.023600
