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Origami‐based designs refer to the application of the ancient art of origami to solve engineering problems of different nature. Despite being implemented at dimensions that range from the nano to the meter scale, origami‐based designs are always defined by the laws that govern their geometrical properties at any scale. It is thus not surprising to notice that the study of their applications has become of cross‐disciplinary interest. This article aims to review recent origami‐based applications in engineering, design methods and tools, with a focus on research outcomes from 2015 to 2020. First, an introduction to origami history, mathematical background and terminology is given. Origami‐based applications in engineering are reviewed largely in the following fields: biomedical engineering, architecture, robotics, space structures, biomimetic engineering, fold‐cores, and metamaterials. Second, design methods, design tools, and related manufacturing constraints are discussed. Finally, the article concludes with open questions and future challenges. This article reviews the state of the art of origami‐based applications in engineering. Publications of origami‐based applications are reviewed according to the following fields: biomedical engineering, architecture, robotics, space structures, biomimetic engineering, fold‐cores, and metamaterials. Design methods and tools are also reviewed. Manufacturing considerations are provided and future challenges discussed.

Origami structures demonstrate great theoretical potential for creating metamaterials with exotic properties. However, there is a lack of understanding of how imperfections influence the mechanical behaviour of origami-based metamaterials, which, in practice, are inevitable. For conventional materials, imperfection plays a profound role in shaping their behaviour. Thus, this paper investigates the influence of small random geometric imperfections on the nonlinear compressive response of the representative Miura-ori, which serves as the basic pattern for many metamaterial designs. Experiments and numerical simulations are used to demonstrate quantitatively how geometric imperfections hinder the foldability of the Miura-ori, but on the other hand, increase its compressive stiffness. This leads to the discovery that the residual of an origami foldability constraint, given by the Kawasaki theorem, correlates with the increase of stiffness of imperfect origami-based metamaterials. This observation might be generalizable to other flat-foldable patterns, in which we address deviations from the zero residual of the perfect pattern; and to non-flat-foldable patterns, in which we would address deviations from a finite residual.

This study investigates the characteristics of a novel origami-based, elastomeric actuator and a soft gripper, which are controlled by hand gestures that are recognized through machine learning algorithms. The lightweight paper–elastomer structure employed in this research exhibits distinct actuation features in four key areas: (1) It requires approximately 20% less pressure for the same bending amplitude compared to pneumatic network actuators (Pneu-Net) of equivalent weight, and even less pressure compared to other actuators with non-linear bending behavior; (2) The control of the device is examined by validating the relationship between pressure and the bending angle, as well as the interaction force and pressure at a fixed bending angle; (3) A soft robotic gripper comprising three actuators is designed. Enveloping and pinch grasping experiments are conducted on various shapes, which demonstrate the gripper’s potential in handling a wide range of objects for numerous applications; and (4) A gesture recognition algorithm is developed to control the gripper using electromyogram (EMG) signals from the user’s muscles.

This study examines the potential of sustainable, biobased paper-based structures as panel/membrane sound absorbers. Although intact paper is naturally impermeable and a poor sound absorber, transforming it into complex three-dimensional origami geometries, specifically the Miura-ori pattern, could produce effective panel/membrane absorbers. Three distinct Miura-ori samples (A, B, and C) were fabricated with increasing geometric complexity, ranging from a simple triangular prism to a complex labyrinthine waveguide. The random incidence sound absorption coefficients of these samples were measured in a validated small-scale reverberation room. The underlying absorption mechanisms were further investigated through modal analysis and non-contact vibration velocity measurements. The results indicate that increased geometric complexity enhances acoustic performance. Sample C, the most complex structure, demonstrated the most consistent broadband absorption. The analysis confirmed a significant positive correlation between acoustic pressure modes, surface vibration velocity, and sound absorption peaks, indicating that acoustic energy dissipation is driven by the vibrational response of the paper membrane coupled with resonant modes in the air gap. This research demonstrates that tunable origami folding techniques using intact paper can be used to design lightweight acoustic treatments for diffuse sound fields in the mid-frequency range.

Origami-based sheet metal (OSM) bending is a promising new die-free folding technique for sheet metal. OSM bending principle is based on deforming the material along a pre-defined fold line, which is determined using material discontinuity (MD) produced by laser or waterjet cutting. The objective of this work is to study and evaluate the fracture in OSM bending under the influence of various MD types, kerf-to-thickness ( k / t ) ratios, and sheet thicknesses. The research goal is to provide information on selecting an optimized k / t ratio and type of MD that allows for fracture-free bending. Four different ductile fracture criteria (DFC) are used and calibrated from experimental data to forecast fracture. The DFC calibration is used to produce a set of critical damage values (CDV) for assessing the possibility of fracture in the OSM bending. In addition, the study provides fracture evaluation using finite element analysis (FEA) integrated with experimental cases for a broader range of OSM bending parameters and MDs. The results demonstrated that an MD with a higher k / t ratio is less likely to fracture during the OSM bending, whereas a higher sheet thickness increases the possibility of fracture. Furthermore, the study identifies the k / t ratio limit that ensures successful bending without fracture and categorizes MD types into two groups based on fracture likelihood. The fracture in the first group is dependent on the limiting k / t ratio, whereas the possibility of fracture in the second group is independent of the k / t ratio due to its topology.

Outstanding properties and advanced functionalities of thermal–regulatory by origami-based architecture materials have been shown at various scales. However, in order to model and manage its programmable mechanical properties by Building Information Modelling (BIM) for use in a covering structure is not a simple task. The aim of this study was to model an element that forms a dynamic shell that prevents or allows the perpendicular incidence of the sun into the infrastructure. Parametric modelling of such complex structures was performed by Grasshopper and Rhinoceros 3D and were rendered by using the V-ray’s plugin. The elements followed the principles of origami to readjust its geometry considering the sun position, changing the shadow in real time depending on the momentary interest. The results of the project show that quadrangular was the most suitable Origami shape for façade elements. In addition, a BIM-based automated system capable of modifying façade elements considering the sun position was performed. The significance of this research relies on the first implementation and design of an Origami constructive element using BIM methodology, showing its viability and opening outstanding future research lines in terms of sustainability and energy efficiency.

Lamina Emergent Torsional (LET) arrays can be used to replace creases in origami-based mechanisms. They can be made of planar materials, which makes them compatible with many designs. However, LET arrays can take up a lot of area and can exhibit significant parasitic motion, which makes them less ideal for some applications, such as in origami-based robotics and deployable space structures. This work presents a compact variation of the conventional LET array, which resolves these issues. An experimental method for fabricating these compact LET arrays, or C-LET arrays, from carbon fiber-reinforced polymer is given. Deflection models for C-LET array torsion segments, with and without interference with other torsion segments, are given. Bending stress and shear stress equations are provided, and the deflection models are combined into a final model that can solve for the deflections of multiple torsion segments in series. The concepts described are demonstrated in a prototype origami-based deployable reflectarray incorporating C-LET arrays. The prototype demonstrates that C-LET arrays provide the desired motion while maximizing the usable area of the deployable reflectarray.

This work investigates the application of origami as the underlying principle to realize a novel 3D printed hand orthosis design. Due to the special property of some origami to become rigid when forming a closed surface, the orthosis can be printed flat to alleviate the most of the post-processing, and at the same time provide rigid support for the immobilized limb in the folded state. The contributions are the origami-based hand orthosis design and corresponding computational design method, as well as lessons learned regarding the application of origami for the hand orthosis design.

Origami-based sheet metal (OSM) bending is an extension of rigid origami technique, where the final 3D structure is created from a single 2D flat pattern by bending. The key aspect of OSM is material discontinuity (MD), which helps achieve a unique dieless bending process. MD is a feature along bend line of blank sheet and it can be fabricated using laser or water jet cutting. Even though a number of successful implementations of OSM bending have been found, these cases are limited only to product development and industrial application. The mechanics of OSM bending with respect to parameters that define MD, blank sheet, as well as the bending process have not been studied. Thus, this study identifies parameters and investigates the effect of identified parameters associated with OSM bending. Parameters studied in this work include design parameters and process parameters. Design parameters are kerf-to-thickness ( k / t ) ratio, web-to-width ( w / b ) ratio, and thickness of sheet ( t ). These are associated with MD design. The process parameters are related to OSM bending process, and they include punch placement ( t + g ), offset distance ( s ), and punch radius ( R P ). Finite element analysis (FEA) is performed to investigate the effect of these parameters on the OSM bending process. The simulated OSM bending cases resulted in successful bending without using a die. The general recommendation is provided for selecting parameters of OSM bending based on results. In addition, the shape of MD is an important factor when designing the OSM bending process.

Detecting small amounts of analyte in clinical practice is challenging because of deficiencies in specimen sample availability and unsuitable sampling environments that prevent reliable sampling. Paper-based analytical devices (PADs) have successfully been used to detect ultralow amounts of analyte, and origami-based PADs (O-PADs) offer advantages that may boost the overall potential of PADs in general. In this study, we investigated two potential clinical applications for O-PADs. The first O-PAD we investigated was an origami-based enzyme-linked immunosorbent assay (ELISA) system designed to detect different concentrations of rabbit IgG. This device was designed with four wing structures, each of which acted as a reagent loading zone for pre-loading ELISA reagents, and a central test sample loading zone. Because this device has a low limit of detection (LOD), it may be suitable for detecting IgG levels in tears from patients with a suspected viral infection (such as herpes simplex virus (HSV)). The second O-PAD we investigated was designed to detect paraquat levels to determine potential poisoning. To use this device, we sequentially folded each of two separate reagent zones, one preloaded with NaOH and one preloaded with ascorbic acid (AA), over the central test zone, and added 8 µL of sample that then flowed through each reagent zone and onto the central test zone. The device was then unfolded to read the results on the test zone. The three folded layers of paper provided a moist environment not achievable with conventional paper-based ELISA. Both O-PADs were convenient to use because reagents were preloaded, and results could be observed and analyzed with image analysis software. O-PADs expand the testing capacity of simpler PADs while leveraging their characteristic advantages of convenience, cost, and ease of use, particularly for point-of-care diagnosis.