Micro air vehicles(MAVs) with a maximal dimension of 15cm or less and a flight speed of 10rn/s have been of interests to both military and civilian application.Lately, there has been growing interest in developing the flexible wings MAVs, which has been discovered that there are many advantages compared to the rigid wing.The investigation of the flexible wing is essentially in the field of fluid-structure coupling, the basic characteristic of which is the interaction of the two media.