Automatic recycling, releasing and charging device and method for multi-rotor unmanned aerial vehicle

The invention discloses an automatic recycling, releasing and charging device and method for a multi-rotor unmanned aerial vehicle. The device comprises a retracting and releasing rod fixed to the top of the multi-rotor unmanned aerial vehicle and a retracting and releasing device fixed to a recycling platform. A charging contact is arranged on a rod body of the retracting and releasing rod, an elastic cushion layer sleeves the rod body outside the charging contact, and an opening corresponding to the charging contact is formed in the elastic cushion layer; the retracting and releasing device comprises a mounting frame connected with the recycling platform, a net body part, a power transmission part and a controller; a first clamping charging head is arranged at the corner of the front end of each grid of the upper net body, and a second clamping charging head is arranged at the corner of the rear end of each grid of the lower net body. The power transmission part comprises a motor, a self-locking transmissio