01/06/2562 ลอตเตอรี่ไทย เกมสุดท้าย หมายเลขลอตเตอรี่ที่ชนะ ชนะลอตเตอรีแน่นอน นักคิด
I propose building a mechanical manta ray as a Underwater Unmanned Vehicle; UUV. The manta ray will have air tanks inside of its wings and a sound device, which will also operate a sonar and an ELF communication system. The air tanks will be flexible rubber type tanks with an array of gases which when hit with a directional sound device will excite the air and gas molecules and expand the tanks, thus flapping the wings.
from: http://ezinearticles.com/?Making-a-Mechanical-Manta-With-Material-Memory-Manufacturing-Methods&id=63209
