No matter whether it is the handle, the barrel, and the spring rope connection are exactly as I originally envisioned. However, as an air cannon, it can do too little kinetic energy conversion. Even if you pull the traction device to the head, you can only hit a weak air potential energy.

My companion thought it had too little elasticity and only one spring rope to release much kinetic energy. My other companions also thought that the material I chose, the fiber cloth, contained too little elasticity and did not have any stretch, making the traction too stiff. According to my product prototype, I also found several holes in the fiber cloth, which were caused by improper handling during manufacturing. I think based on the above points, the material selection aspect is the main reason for the failure. I should have replaced the fiber arrangement with a fabric/material that is more stretchy, flexible, and not easily damaged by tension.