■Biomimetics
Today,we’ll talk about biomimetics.
In recent years, we see new products in the world that simulate the characteristics of living things. In this way, the “Scientific Technology” that is used to observe and analyze the structures, functions, and manufacturing processes of living things, and to develop new technologies and build products based on the ideas of the scientific technology is called the “Biomimetics”.

■Cross-sectional structures and stress distributions around holes of bamboo
I have found an interesting paper on bamboo, which is also used as a natural structural member.
It is clear that bamboo has evolved while optimizing itself so that it can withstand the environment under the load of bending caused by wind, etc.
Pic. 1(a) shows a cross-section of Phyllostachys pubescens with the outer epidermis in the shape of a figure-of-eight and the inner spots (vascular bundles) in the shape of petals with being arranged in different sizes and orientations.

When the inner petal-shaped vascular bundle is enlarged in Pic.1(b), it can be seen that it is arranged so as to protect the most important vessel as a living organism, the later sieve part, and the like.

Pic. 2(a) shows the results of a stress measurement experiment using the photoelasticity method using a model similar to the bamboo cross-sectional shape, in which portions of equal stress appear as stripes.

From this result, the optimum design for reinforcing the vessel and sieve tubes can be obtained by arranging the reinforcing members as shown by the stress distribution, and the arrangement of the fibers in Pic.1(a),(b) shows the result depending on the stress state received in the growth process.
Mr. Eisaku Umezaki et al. demonstrated this support using photoelasticity and finite element analysis in combination.

In the near future, cylindrical structures simulating the cross-sectional structure of bamboo may be seen.
Our LSM9100 product family is active when we want to evaluate stress distributions using such photoelastic techniques.

This instrument can quantitatively measure large strains (stress and retardation) of resin, and can compare strains caused by differences in shapes.
Fully Automatic polarimeter LSM-9100 product family

In our showroom,you can experience machine demo by your samples,please feel free to inquire by email or phone.

 

■Reference
(1) “What Is Biomimicry?” “How Do You Select Themes for Lifestyle Tokyo Institute of Technology Lectures in Science?” Poplar, ISBN 978-4591147405. (2015)
(2) Fumio Nogata：Mechanical Sensing Ability and Shape Control by Electric Signals in Plants,
The Journal of the Japanese Bio-Electrical Research Society, Vol.12, 21-26, (1998)
(3) Masato Sato, Eisaku Umezaki：Stress analysis around bamboo vascular bundles under bending,
The Japan Society of Mechanical Engineers, M&M lectures proceedings, 2000, p.589-590, (2000)