Performance Investigation and Improvement of a Two-DOF Inertial Piezoelectric Robotic Insertion Device for Capillary Micropuncture

Insertion of capillaries poses a great challenge to biomedical researchers owing to the demanding requirements of multi-DOF, large stroke, high resolution, and adjustable force. In this article, the output performance of a two-DOF inertial piezoelectric robotic insertion device (PRID) was studied and improved, and its application potential in vascular micropuncture was verified. First, configuration and working principle of the PRID were elaborated. Next, theoretical analyses were conducted to obtain the adjustable pretightening force range, thereby guiding the improvement of the puncture force characteristics. Then, a series of experiments were carried out to study its output characteristics. Eventually, a robotic micromanipulation system was proposed, and the capillary micropuncture tests were implemented. The experimental results indicated that the PRID achieved linear and rotary strokes of 36 mm and 360°, the puncture force range was from 16.85 mN to 154.26 mN; the coupling rates in linear and rotary directions separately were 4.04% and 3.21%, the displacement resolutions in linear and rotary directions separately were 6.5 nm and 0.6 
μ
rad, and the exciting frequency could be used to actively adjust the puncture force. Furthermore, the PRID successfully completed the micropuncture of two sizes of silicone capillaries on the eyeball model in collaboration with a six-DOF piezoelectric platform. The PRID can be applied in the field of micropuncture of cells and blood vessels with different shapes and sizes.