Rocket nozzle swing angle measuring method and device

The invention provides a rocket nozzle swing angle measuring method and device. The method comprises the following steps: fixing a positioning lantern ring provided with a three-axis acceleration sensor to the surface of a nozzle, and acquiring an initial signal output by the three-axis acceleration sensor; after the positioning lantern ring is fixed to the surface of the nozzle, attaching the first positioning face of the positioning lantern ring to an axial positioning table on the nozzle, attaching the inner side profiling face of the positioning lantern ring to the peripheral face of the nozzle; driving the nozzle to rotate, and acquiring a swing signal output by the three-axis acceleration sensor; and calculating the swing angle of the nozzle according to the initial signal and the swing signal. According to the method, the swing angle of the nozzle is determined by directly utilizing an acceleration measurement mode, and the measurement data confidence is high; and when the precision of the acceleration