Structures with Anomalous Properties: Auxetics

—Structures with negative Poisson's ratio—

physical model
       --> [Ref. i]
A phycal model (steel) was fabricated by using photo-etching (produced in cooperation with Kyoritsu Model Mfg. Co., Ltd.).

A unit cell obtained by optimization.
MIP (=mixed integer programming) was used.

(undeformed state)

(deformed state)

(movie in full view: 9MB)
(movie with close up: 7MB)

This auxetic structure, i.e., the structure exhibiting negative Poisson's ratio, was generated by the method described in the following article:
  1. R. Kureta and Y. Kanno: A mixed integer programming approach to designing periodic frame structures with negative Poisson's ratio. Optimization and Engineering, 15, pp. 773-800 (2014).
The physical model was produced in cooperation with iŠ”j‹€—§–ΝŒ^ (Kyoritsu Model Mfg. Co., Ltd.).

(c) Yoshihiro Kanno (2013)