3d Printing for Prototypes of Thin-film Pzt/polymer Microstructures

This work explores the viability of using 3D printing as a rapid-prototyping technique for microrobotic appendages made from thin-film PZT/polymer materials. First, the possibility of integrating piezoelectric materials into millimeter-scale (meso-scale) polymer melt-printed structures was investigated. Next, one specific robot limb geometry was chosen as a basis to compare structural modeling techniques and perform scaling analysis. Scaling was performed to select the dimensions of one micro-scale device and two differently-sized prototypes. Beambending analysis was used to produce a simple analytical model, and finite element analysis was used to generate more accurate computational models. One size of devices has been fabricated to date, and its dynamic behavior was tested. From modeling and experiments, integrating PZT into the printing process was determined to be non-trivial. Additionally, the two modeling techniques predict static behavior relatively close to each other. However, the fabricated Large Printed limb exhibited static behavior much smaller than the models predict. Finally, the scaling analysis produces predictable results for the small printed device, but shows poor accuracy for the large printed device. Based on these results, we conclude that, while more investigation is necessary, 3D printing shows promise for prototyping of thin-film PZT/polymer microrobots. Introduction A wide range of micro robots are currently being explored for a variety of applications. For example, a sub-millimeter swimming micro robot utilizing a piezoelectric micro-motor has been proposed for navigation inside blood vessels in the human body [1]. In another set of studies, flying microrobots have been extensively designed and studied for surveillance and search-andrescue applications [2]. Further, much work has been completed investigating micro-scale walking robots. One walking robot was designed to be controlled with a neural network [3]. Figure 1. Several microrobots currently being explored for a variety of applications. (A) swimming robot for navigation inside the human body [1], (B) flying robot for surveillance [2], (C) walking robot controlled by a neural network [3], and (D) hexapod robot with thin-film piezoelectric actuators and integrated polymer for search-and-rescue [4]. A B C D