Anti-collision unmanned aerial vehicle for three-dimensional modeling engineering surveying and mapping

The anti-collision unmanned aerial vehicle for three-dimensional modeling engineering surveying and mapping comprises an unmanned aerial vehicle body, an extension arm and a power piece, the extension arm is fixedly installed on the periphery of the unmanned aerial vehicle body, the power piece is installed at the end of the extension arm, and the upper end of the unmanned aerial vehicle body is connected with an anti-collision mechanism; the anti-collision mechanism comprises a strip-shaped groove, a transverse fixing rod, a first spring and a U-shaped sleeving block. According to the anti-collision unmanned aerial vehicle, the anti-collision mechanism used for top end collision prevention is arranged, so that the upper end of the whole unmanned aerial vehicle can be better prevented from being collided and damaged in the flying period, the whole unmanned aerial vehicle has buffering performance, and direct falling caused by hard collision can be avoided; and a buffer assembly for preventing ground impact fo