CNN的新闻,大家可以读一下 The Bluefin-21 is a probe equipped with side-scan sonar, or acoustic technology that creates pictures from the reflections of sound instead of light. The device sends a pulse that produces a three-dimensional map of the seafloor, according to the U.S. Navy, which owns the Bluefin-21 used in the search. An operator on the surface programs the vehicle. "When it reaches the appropriate depth, it will turn on its sensors," said David Kelly, the president and CEO of manufacturer Bluefin Robotics. "It will then run what's called the lawn mower pattern, which is a series of parallel lines or tracks, where it will go back and forth just like mowing your lawn."