Piezoelectric vibration platform

This piezoelectric vibration platform is used for providing a frequency-rich input to microrobotic components and could also be used in linear positioning applications. It consists of a low-profile sarrus linkage driven by four piezoelectric bending actuators acting in parallel. This was designed and built as part of an exploration into compact out-of-plane displacement amplification mechanisms. The idea is to achieve a linear output motion that is similar in magnitude to the thickness of the device. Here, an output motion of ~250 um is achieved for the ~1 mm thick device.

Free displacement: This video shows the free displacement of the device. Note that the sarrus linkage is at the center of its stroke when the actuation voltage is zero:

Displacement measurement: This video shows the use of a scanning laser Doppler vibrometer to measure the displacement of the structure at various points. The video speed is increased to 10x for brevity:

Measurement results: The results of the displacement measurements are shown in this video. The total magnitude of the motion and deviation throughout the device can be seen. The tipping of the platform, which is undesirable, is likely due to the system being slightly statically overconstrained and in part due to small assembly errors: