Wingtip folding driving mechanism based on shape memory alloy torque tube

The invention discloses a wingtip folding driving mechanism based on a shape memory alloy torque tube, and relates to the technical field of aircrafts, the wingtip folding driving mechanism comprises a driving unit, the driving unit comprises a bias torsion spring and a shape memory alloy torque tube arranged between a wing main body and a wingtip; one end of the shape memory alloy torque tube is fixedly connected with the wing main body, the other end of the shape memory alloy torque tube is circumferentially clamped with the flange, the flange is fixedly connected with one end of the sleeve, the sleeve sleeves the shape memory alloy torque tube, the sleeve is in clearance fit with the shape memory alloy torque tube, the sleeve is fixedly connected with the wingtip, and the offset torsion spring sleeves the sleeve. One end of the bias torsion spring is fixedly connected with the wing main body, and the other end is fixedly connected with the wingtip; the braking unit is used for braking rotation of the flang