Reversed-torsion-type crush energy absorption structure and its inexpensive partial-heating torsion manufacturing method based on origami engineering

Current vehicle energy absorbers face two problems during a collision in that there is only a 70% collapse in length and there is a high initial peak load. These problems arise because the presently used energy-absorbing column is primitive from the point of view of origami. We developed a column called the Reversed Spiral Origami Structure (RSO), which solves the above two problems. However, in the case of existing technology of the RSO, the molding cost of hydroforming is too expensive for application to a real vehicle structure. We therefore conceive a new structure, named the Reversed Torsion Origami Structure (RTO), which has excellent energy absorption in simulation. We can thus develop a manufacturing system for the RTO cheaply. Excellent results are obtained in a physical experiment. The RTO can replace conventional energy absorbers and is expected to be widely used in not only automobile structures but also building structures.

Study on 3D Truss Flexible Shape Bridge Using Origami Engineering

<p>The purpose of this paper is to propose a design method when designing a bridge from origami engineering. Origami engineering has the characteristics of "foldable", "high rigidity" and "engineering design".</p><p>Origami engineering is widely used from interior design to the space field. There are various types, but in this paper, we focus on Yoshimura folds. Focusing on the characteristics of Yoshimura folds, we use it as the main girder of the bridge in this study. Analyze the properties of Yoshimura folds and devise a bridge model. Bridge modeling is determined by the section angle θ, the relationship between span and rise, and the relationship between girder height and span. Make a model and check the folding behavior. Determine the parameters for making a wooden bridge with a span of 8 m. Finite element method analysis and eigenvalue analysis are performed from the determined parameters. Stress analysis and resonance are examined based on the analysis results. Finally designed and produce a wooden footbridge.</p><p>In this study, we designed and constructed one design proposal using origami engineering. By limiting the material to wood, it became a bridge like this one. However, it can be said that various shapes can be expected depending on the material. In the future, we can expect various designs for deployable bridges using origami engineering.</p>

Current-Dependent Dynamics of Bidirectional Self-Folding for Multi-Layer Polymers Using Local Resistive Heating

The purpose of this paper is to characterize the dynamics and direction of self-folding of pre-strained polystyrene (PSPS) and non-pre-strained styrene (NPS), which results from local shrinkage using a new process of directed self-folding of polymer sheets based on a resistively heated ribbon that is in contact with the sheets. A temperature gradient across the thickness of this shape memory polymer (SMP) sheet induces folding along the line of contact with the heating ribbon. Varying the electric current changes the degree of folding and the extent of local material flow. This method can be used to create practical three-dimensional (3D) structures. Sheets of PSPS and NPS were cut to 10 × 20 mm samples, and their folding angles were plotted with respect to time, as obtained from in situ videography. In addition, the use of polyimide tape (Kapton) was investigated for controlling the direction of self-folding. Results show that folding happens on the opposite side of the sample with respect to the tape, regardless of which side the heating ribbon is on, or whether gravity is opposing the folding direction. The results are quantitatively explained using a viscoelastic finite element model capable of describing bidirectional folds arising from the interplay between viscoelastic relaxation and strain mismatch between polystyrene and polyimide. Given the tunability of fold times and the extent of local material flow, resistive-heat-assisted folding is a promising approach for manufacturing complex 3D lightweight structures by origami engineering.

The study and optimization of the behavior and energy absorbed in the frontal impact by a rectangular metal workpiece with an Origami core

The bumper systems (beams and face bars) are parts of the car body structure, one of the most important components of an auto vehicle because of its role in absorbing the energy of an impact by deformation. The main objective of this paper is to study, optimize the built shape of the frontal members beams used in the endurance structure of motor vehicles in terms of their ability to absorb internal energy resulting from a frontal impact under the principles of sustainability. The study combines the classical technology used in the construction of vehicles with, the Origami Engineering” technique, which is generally used by NASA, but also by engineers in other fields: aeronautics, nanotechnology or medical technique. Simulation analyses were performed using the finite element on different types of thin-walled metal tubes, but also an origami structure.

Autonomous Multifunctional Vehicle With Integrated Bio-Inspired SMA Actuated Grasper

The space exploration activities are merging new technologies in order to develop systems challenged to achieve capabilities for high mission experience. Inspired by the numerous applications in space exploration, with the integration of shape memory alloys (SMAs), a 3D printed continuous All Terrain Grasper Transport (AT-GT) vehicle with implemented multi-locomotion grasper was created. In order to reduce failure of the mechanical system, the vehicle is equipped with SMA suspension and SMA tensioner of a pulley system with adaptable height able to achieve movement on a given trajectory and adjust to any terrain. SMA actuators provide controllable actuation based on the simplicity of their design and the shape memory effect. By using the advantages of the origami engineering, soft robotics and smart material implementation, a bio-inspired autonomous grasper was integrated on the AT-GT, capable of leaving the vehicle, grabbing an object and bringing it back to the vehicle. The concept development, the analytical models and the prototype including the benefits of the combined work of the vehicle and the grasper are presented.

Untethered control of functional origami microrobots with distributed actuation

Deployability, multifunctionality, and tunability are features that can be explored in the design space of origami engineering solutions. These features arise from the shape-changing capabilities of origami assemblies, which require effective actuation for full functionality. Current actuation strategies rely on either slow or tethered or bulky actuators (or a combination). To broaden applications of origami designs, we introduce an origami system with magnetic control. We couple the geometrical and mechanical properties of the bistable Kresling pattern with a magnetically responsive material to achieve untethered and local/distributed actuation with controllable speed, which can be as fast as a tenth of a second with instantaneous shape locking. We show how this strategy facilitates multimodal actuation of the multicell assemblies, in which any unit cell can be independently folded and deployed, allowing for on-the-fly programmability. In addition, we demonstrate how the Kresling assembly can serve as a basis for tunable physical properties and for digital computing. The magnetic origami systems are applicable to origami-inspired robots, morphing structures and devices, metamaterials, and multifunctional devices with multiphysics responses.

Investigation of Laser Hardening Forming Method for Thin Steel Plate From a View of Origami Engineering

In recent years, products have been miniaturized and multi-functionalized, and the importance of integration in compact machine tools has increased. In this study, we propose integration via laser hardening forming which combines laser hardening and laser forming on a compact machine toolfor thin steel sheets. For the processing, the deformation and quenching were considered during repeated laser scanning repeated at the same location. In addition, to apply laser quenching forming to origami engineering, a test piece with resilience was prototyped. As a result, problems in repeated laser scanning were clarified, and the tool’s applicability to origami engineering was demonstrated.

The Concept of a Poly-Functional Ballistic Shield

Police and military units are employing the use of additional, portable protection in the form of various types of ballistic shields ever more often. They are not only used for protecting a single operator, but rather entire assault groups or bystanders. The work analyses the ballistic shields used presently and the requirements of the law enforcement forces; on this basis, the assumptions used for designing a poly-functional ballistic shield have been formulated. The design employed so-called “origami engineering”, i.e. a field tasked with designing geometrically-shifting materials by changing the location of the components. The prototype’s design is presented, and the path to its development is indicated.