Abstract: The invention discloses a method for predicting a residual strength of a composite material after impact. The method includes: acquiring a first frequency value of a composite material to be tested after impact damage; determining a first frequency change rate according to an initial frequency value and the first frequency value of the composite material to be tested; inputting the first frequency change rate to a pre-constructed residual strength prediction model to predict a first residual strength of the composite material to be tested; the first frequency value and the initial frequency value being obtained by a modal test. Further, residual strength prediction may be performed on the composite material in service, the position and the size of impact damage, the impact energy, the shape and quality of the impact object are not required to be determined, which avoids a rigidity test of the composite material in service.

Abstract: A vibration power generation device, comprising: three power generation mechanisms with energy harvesting directions the same as three directions of three-dimensional coordinates, each of the power generation mechanisms including a piezoelectric power generation part and a magnetoelectric power generation part, wherein the piezoelectric power generation part includes two M-shaped structural beams and a first permanent magnet fixed in the middle of each of the M-shaped structural beams; and the magnetoelectric power generation part includes two magnetoelectric power generation components that are arranged on both sides of the piezoelectric power generation part and are in the same axial direction as the two first permanent magnets, and each of the magnetoelectric power generation components includes a second permanent magnet, a spring with one end connected to the second permanent magnet, a sleeve that houses the second permanent magnet in a cavity, and a coil wound on a surface of the sleeve.