Investigation of ways to make toy projectiles fly farther, straighter, and safer by adopting memory foam

[摘要] (cont.) The refined models were prototyped and evaluated through the performance tests as well. The refined model #13-1 has the same range of flight and 37.69% better accuracy than the state-of-the-art projectiles, and the refined model #13-3 has the 31.78% longer range of flight and comparable accuracy to the state-of-the-art projectiles. In conclusion, the final model was attained with specific concepts: The surface of the projectile should be smooth without bump between head and body; Two things should be avoided: too high mass because it limits the distance of flight and generates high kinetic energy density, and too low mass because it causes unsatisfied accuracy; The uniform density distribution is desired for straightness of flight; The head of the projectile should be close to streamline; The contact area should be composed with soft material that would be memory foam to protect users from injury; Stiff material not deformed by air pressure should be installed in the head and the shape of the stiff material should not sharp; The occupancy of stiff material;;s volume in the head should not exceed 25% of the whole volume of the head.

[发布机构] Massachusetts Institute of Technology