最強の折り畳みへルメット

抄録

Nowadays, self-protection is a very important issue for everyone, and it is an urgent request to invent a helmet which is convenient for storage, for example, the one which is not disturbing to pass through the passages between desks and enough small to put in lockers in class room. There are many foldable helmets in market, but they can be folded in one direction only, so those folded states are not small enough for general request. Therefore, we challenged to invent a helmet which is foldable in two directions. In this competition proposed by NHK program, we should invent a hat which is foldable into compact shape and also strong enough to absorb shock-energy as much as present helmets. Those requests remind us to design energy-absorbing for car collision; decreasing the peak of force for energy-absorbing material and lengthening deformation-stroke as much as possible. It is also necessary to invent a cover of head which is foldable into a box regulated by NHK. Even if we can find a foldable cover small enough, it can absorb small amount of shock-energy, and so we should attach some energy-absorbing materials enough to protect heads. Hence by using Origami technology for development and contraction of material, we found a design of a helmet with corrugated cardboards which suffice absorbing shock-energy, and in the competition we could win the competitor who were also very strong. Anyway, since we realized how much the Origami technology is useful through those experiments, we decided to write those results in a paper.