Development of Cylinder Structure Bending Property Measurement Method and an Example of New Stab Proof Clothing Structure

In Japan, where a safe and secure society has been established, stab proof clothing that are suitable for police and security officers supporting are required. So far, most of the stab-proof clothing is made of the metal plate or thick multi-layered fabric with high-strength fibers. It is commonly used as a stab-proof vest because it cannot cope with the large deformations, which caused by the joints such as arms or neck. This research aims to develop high flexible stab-proof clothing that can be applied in large-deformation part such as joints with high stab-proof performance. We developed a testing device that can measure bending characteristics under the same conditions as when the stab proof clothing is actually worn on the human body. The usefulness of the evaluation method was confirmed. And the factors that affect the bendability of the elbow joint were also be studied. The mechanical properties of the material and the gap between the arm and the cylindrical structure are greatly affected, and the effect of each bending angle on the bending moment is different. We considered the deformation of the material when it bending and then proposed a new stab-resistant material structure and trial production. The cylindrical bending test shows that the flexibility of the new structure is greatly improved.