Research Theme / 研究テーマ
Extendable Mechanisms Exploiting Characteristics of a Deployable Origami /
折り紙に着想を得た新たな伸縮機構の開発
Research Topics / 研究内容
Modeling and Displacement Analysis of Origami Spring Considering Collision and Deformation of Components /
部材の干渉と変形を考慮したOrigami Spring の実挙動の機構学的考察
The Origami Spring is one of the convertible origamis and its macroscopic motion is often regarded as a single Degree-of-Freedom (DoF) motion while in theory, its DoF is three DoF mechanism. In this paper, a new displacement analysis was introduced to study the behavior of Origami Spring. The Origami Spring was modeled as a link mechanism which includes rigid and compliant components. In particular, folding was represented by a revolute joint, and deformation which is assumed to have an effect on the structural stability was represented by a string. With this model, the displacement analysis is carried out. As the result, it was revealed that a single DoF contributed to translational motion and the other two DoF have a role of adjustment to avoid collision between components in a narrow range. In addition, strain energy based on deformation of string was introduced in order to investigate the macroscopic motion. As the result, its effectiveness was revealed by comparison of theoretical and experimental motions.
Transactions of the JSME, Vol. 85, No. 873. May 2019. / 日本機械学会論文集, 85巻, 873号, 5月 2019.
Design of a Novel Multiple-DOF Extendable Arm with Rigid
Components Inspired by a Deployable Origami Structure
An extendable robot inspired by origami is designed, analyzed, and tested. Its deployable origami structure has a large extension ratio, allowing the robot to extend the body length multiple times. The new robot, however, differs from the existing origami structure in two aspects. One is that the robot mechanism consists of all rigid bodies, unlike the prior origami that exploits structural deformation for creating flexible configurations. The other is that new origami-inspired robot has multiple active degrees of freedom, allowing for taking various postures, unlike most deployable mechanisms composed of rigid components having a single DOF. When developing a mechanism based on an origami structure, we often encounter the deformations of parts during the transition from the contracted to the extended configurations. Previously, we analyzed the motion of a deployable origami structure considering the foldings’ deformation and showed that they do
not have any kinematic roles but give a large effect to constrain the motion. Thus, we come to the idea that by removing such parts, a novel rigid extendable mechanism with multiple DOF can be obtained, which can achieve a large extension ratio and a high transformability only by its kinematic structure, beyond an original origami structure.
[IEEE Robotics and Automation Letters, Vol. 5, Issue 2, pp. 2730-2737, April 2020.]