Inertial Piezoelectric Actuation of a Needle Insertion Device for Minimally Invasive Surgery *

Robotic-assisted needle intervention has shown great prospects in minimally invasive surgery (MRI), where the needle insertion device (NID) is an important component. Some sophisticated intervention practices require the NID to have the characteristics of high resolution, enough insertion force, and compact structure. In this work, a NID driven by an inertial piezoelectric actuator is developed and validated by experiments. The actuator consists of a triangular configured compliant driving mechanism and a piezoelectric stack installed inside to meet the requirements. A prototype with a compact structure of 86 × 104 × 41 mm ³ is fabricated to test the performance of the proposed NID. Both the no-load test and phantom test are carried out. Experimental results show that the developed NID reaches a resolution of 4.7 nm (fine positioning mode), a maximum velocity of 6.89 mm/s, and a maximum insertion force of 2.4 N. The resolution and structure volume are superior to the traditional NID, and the insertion force is higher than the same type of NID. A potential application of the proposed NID is high-precision needle intervention with limited working space, such as MRI-based needle biopsy.