In the last spring festival, I’ve tried to contact 3 companies which can manufacture carbon fiber in Xian. One of them refused me politely, and 2 of them silently refused me.As the deadline coming, I began to worry about my material. Later I just recalled that one of my uncles works in IEECAS—institution of earth environment, Chinese academy of science.I asked him if I can have some carbon fiber, he said that he doesn’t have carbon fiber but provided some choices for me. The next day, five kinds of materials were put in front of me, and I chose the one with sliver light.