Research on a small backward piezoelectric bimorph actuator at low frequency based on the Z-shape dual flexible hinge mechanism (ZDFHM)

Abstract Inertial piezoelectric drive devices play an important role in manufacturing, but there are many problems such as backward motion, low displacement accuracy, and poor stability. A small backward piezoelectric bimorph actuator is proposed, which uses the principle of inertial drive with the Z-shape dual flexible hinge mechanism (ZDFHM). The ZDFHM makes the actuator have a simple driving signal and circuit, stable output, and small backward ratio. Dynamic model, simulation and experiment are conducted on the ZDFHM and the actuator, comparing with preliminary experimental data, the maximum displacement error between simulation and experiment is 9.4%, which verifies the dynamic model and simulation are reasonable. Experimental results have shown that the proposed actuator can be driven by low-frequency electrical signals, the minimum operating frequency can reach 1 Hz. When using the ZDFHM, the displacement resolution measured at a working frequency of 1 Hz is 0.32 μ m, with the backward ratio of the actuator 3.9%.