Inflatable structures offer the potential of compactly stowing lightweight structures,
which assume a fully deployed state in space. An important category of space inflatables
are cylindrical booms, which may form the structural members of trusses or the support
structure for solar sails. Two critical and interdependent aspects of designing inflatable
cylindrical booms for space applications are i) packaging methods that enable compact
stowage and ensure reliable deployment, and ii) rigidization techniques that provide
long-term structural ridigity after deployment. The vast literature in these two fields
is summarized to establish the state of the art.

/pdf/review-of-inflatable-booms-for-deployable-space-structures-5atrdj1lxs.pdf

Review of Inflatable Booms for Deployable Space Structures: Packing and Rigidization

This is an overview of current research in origami applied to mechanical engineering. Fundamental concepts and definitions commonly used in origami are introduced, including a background on key mat...

https://journals.sagepub.com/doi/pdf/10.1177/0954406215597713

A review of origami applications in mechanical engineering

The primary goal of dynamic building envelopes is to meet and balance antagonistic performance criteria utilizing automatic operation. As opposed to static systems, automated shading and daylighting systems are increasingly being used in facade design with the intent to improve building performance. Taking this into consideration, the question that arises is whether such systems can significantly improve buildings energy performance and occupants׳ visual and thermal comfort. The present paper is a review of dynamic operation methods of shading/daylighting systems and their associated implications in building energy balance. Based on the subject distribution of the reviewed studies, the majority of the systems examined are versions of motorized blinds while the analysis of new emerging ideas on deployable and foldable facade systems is limited. User acceptance is quite crucial and is strongly dependent on the system׳s intuitive operation. According to the paper findings, energy savings with automatically controlled blinds depend on the type of control strategy and their connection to dimmable electric lighting systems. Even though control strategies enhance energy performance and occupants׳ comfort, their level of complexity highly affects their efficiency and therefore influences their performance.

Dynamic operation of daylighting and shading systems: A literature review

Using origami folding to construct and actuate mechanisms and machines offers attractive opportunities from small, scalable, and cheap robots to deployable adaptive structures. This paper presents the design of a bio-inspired origami crawling robot constructed by folding sheets of paper. The origami building block structure is based on the Kresling crease pattern (CP), a chiral tower with a polygonal base, which expands and contracts through coupled longitudinal and rotational motion similar to a screw. We design the origami to have multi-stable structural equilibria which can be tuned by changing the folding CP. Kinematic analysis of these structures based on rigid-plates and hinges at fold lines precludes the shape transformation associated with the bistability of the physical models. To capture the kinematics of the bi-stable origami, the panels' deformation behavior is modeled utilizing principles of virtual folds. Virtual folds approximate material bending by hinged, rigid panels, which facilitates the development of a kinematic solution via rigid-plate rotation analysis. As such, the kinetics and stability of folded structures are investigated by assigning suitable torsional spring constants to the fold lines. The results presented demonstrate the effect of fold-pattern geometries on the snapping behavior of the bi-stable origami structure based on the Kresling pattern. The crawling robot is presented as a case study for the use of this origami structure to mimic crawling locomotion. The robot is comprised of two origami towers nested inside a paper bellow, and connected by 3D printed end plates. DC motors are used to actuate the expansion and contraction of the internal origami structures to achieve forward locomotion and steering. Beyond locomotion, this simple design can find applications in manipulators, booms, and active structures.

https://iopscience.iop.org/article/10.1088/1361-665X/aa721e/pdf

A crawling robot driven by multi-stable origami

Extending the method coined virtual-center-based (VCB) for synthesizing a group of deployable platonic mechanisms with radially reciprocating motion by implanting dual-plane-symmetric 8-bar linkages into the platonic polyhedron bases, this paper proposes for the first time a more general single-plane-symmetric 8-bar linkage and applies it together with the dual-plane-symmetric 8-bar linkage to the synthesis of a family of one-degree of freedom (DOF) highly overconstrained deployable polyhedral mechanisms (DPMs) with radially reciprocating motion. The two 8-bar linkages are compared, and geometry and kinematics of the single-plane-symmetric 8-bar linkage are investigated providing geometric constraints for synthesizing the DPMs. Based on synthesis of the regular DPMs, synthesis of semiregular and Johnson DPMs is implemented, which is illustrated by the synthesis and construction of a deployable rectangular prismatic mechanism and a truncated icosahedral (C60) mechanism. Geometric parameters and number synthesis of typical semiregular and Johnson DPMs based on the Archimedean polyhedrons, prisms and Johnson polyhedrons are presented. Further, movability of the mechanisms is evaluated using symmetry-extended rule, and mobility of the mechanisms is verified with screw-loop equation method; in addition, degree of overconstraint of the mechanisms is investigated by combining the Euler's formula for polyhedrons and the Grubler–Kutzbach formula for mobility analysis of linkages. Ultimately, singular configurations of the mechanisms are revealed and multifurcation of the DPMs is identified. The paper hence presents an intuitive and efficient approach for synthesizing PDMs that have great potential applications in the fields of architecture, manufacturing, robotics, space exploration, and molecule research.

Synthesis, Mobility, and Multifurcation of Deployable Polyhedral Mechanisms With Radially Reciprocating Motion

https://onlinelibrary.wiley.com/doi/pdf/10.1002/advs.202000636

Engineering Origami: A Comprehensive Review of Recent Applications, Design Methods, and Tools

As conventional approaches for calculating natural frequencies do not make full use of the inherent symmetry of a structure, the rising degree of freedoms often leads to significant increase in computational demand. In this study, a simplified technique for analyzing dynamic characteristics of symmetric prestressed structures is described using group theory. First, the generalized eigenvalue equation of a prestressed structure based on tangent stiffness matrix and lumped mass matrix is built to get natural frequencies and the corresponding vibration shapes in which the contribution of initial prestresses is considered. A symmetry-adapted coordinate system for the structure is adopted to block-diagonalize the stiffness and mass matrices. The complexity of generalized eigenvalue equation is reduced by solving the mutually independent subspaces, and thus natural frequencies and the corresponding vibration modes could be obtained. Illustrative examples point out the general procedure, and show the sup...

Generalized Eigenvalue Analysis of Symmetric Prestressed Structures Using Group Theory

Deployment simulation of foldable origami membrane structures

\n Flat-foldable origami tessellations are periodic geometric designs that can be transformed from an initial configuration into a flat-folded state. There is growing interest in such tessellations, as they have inspired many innovations in various fields of science and engineering, including deployable structures, biomedical devices, robotics, and mechanical metamaterials. Although a range of origami design methods have been developed to generate such fold patterns, some non-trivial periodic variations involve geometric design challenges, the analytical solutions to which are too difficult. To enhance the design methods of such cases, this study first adopts a geometric-graph-theoretic representation of origami tessellations, where the flat-foldability constraints for the boundary vertices are considered. Subsequently, an optimization framework is proposed for developing flat-foldable origami patterns with four-fold (i.e., degree-4) vertices, where the boundaries of the unit fragment are given in advance. A metaheuristic using particle swarm optimization (PSO) is adopted for finding optimal solutions. Several origami patterns are studied to verify the feasibility and effectiveness of the proposed design method. It will be shown that in comparison with the analytical approach and genetic algorithms (GAs), the presented method can find both trivial and non-trivial flat-foldable solutions with considerably less effort and computational cost. Non-trivial flat-foldable patterns show different and interesting folding behaviors and enrich origami design.

Particle Swarm Optimization-Based Metaheuristic Design Generation of Non-Trivial Flat-Foldable Origami Tessellations With Degree-4 Vertices

A prestressed cable-strut structure is usually regarded as a mechanism before being prestressed. Under the action of initial prestresses, the internal infinitesimal mechanisms can be rigidi...

Jian Feng

Papers

Engineering Origami: A Comprehensive Review of Recent Applications, Design Methods, and Tools

Generalized Eigenvalue Analysis of Symmetric Prestressed Structures Using Group Theory

Deployment simulation of foldable origami membrane structures

Particle Swarm Optimization-Based Metaheuristic Design Generation of Non-Trivial Flat-Foldable Origami Tessellations With Degree-4 Vertices

Feasible Prestress Modes for Cable-Strut Structures with Multiple Self-Stress States Using Particle Swarm Optimization