This paper introduces a multi-directional miniature piezoelectric vibration energy collection device

with a zigzag shape, which is surrounded by a square frame with a size of 34 mm × 2 mm × 1 mm, and its internal

structure consists of four asymmetric combined cantilever beams.The main cantilever beam is fixed on the inner wall

of the frame and is perpendicular to the z direction, whereas the secondary cantilever beam is connected to the end

mass block of the main cantilever beam.In this study, first, the dynamic model of a composite cantilever beam vibration

system under basic excitation is established.Subsequently, through a finite element simulation, the influence

of different stiffness and mass values on the displacement amplitude is analyzed and compared, the vibration characteristics

of the composite cantilever beam system are verified, and the optimal structural parameters are determined.

When the thickness of the primary and secondary cantilever beams is 0.3 mm, the optimal inertial mass of the primary

and secondary mass blocks is 619.32 and 342.3 g.The simulation calculation shows that the collectable electric

power in the z direction is 3.138 5 mW, and the collectable power in the x and y directions is 0.720 5 mW.Finally,

an experimental platform of a miniature energy collector is built, and in actual testing, the output power in the z direction

is 2.85 mW, the output power in the x, y direction is 0.57 mW.