Piezoelectric transducer design for an ultrasonic scalpel with enhanced dexterity for minimally invasive surgical robots

Abstract

Ultrasonic scalpel offers the advantages of reliable and simultaneous vessel cutting and sealing and provide self-cleaning capacity with less thermal damage and smoke. However, the current long, straight, and rigid ultrasonic scalpels have limited degrees of freedom, which restricts the operation dexterity of the minimally invasive surgical robot. To address such problem, a novel design of a minimized piezoelectric transducer that can be integrated at the distal end of a multi-degrees of freedom robotic instrument, has been proposed and implemented in the work. This concept can take full advantage of ultrasonic scalpels while guaranteeing the dexterity of the sufficient robotic operation. By employing the electromechanical equivalent method, the initial dimensional parameters of the ultrasonic transducers have been calculated. The optimal transducer design has been achieved by utilizing the proposed optimization method, which is based on finite element method, design of experiment, response surface method, and multi-objective genetic algorithm. The transducer prototype was manufactured, and its dynamic characteristics were further investigated by using impedance analyzer. The results reveal that the actual features of the transducer closely match the finite element method-based simulation results. In-vitro experiments have been performed to show that the vibration amplitude and frequency can meet the requirements for dissection and coagulation of tissues.

Optimized integrated design of a high-frequency medical ultrasound transducer with genetic algorithm

“…Non-imaging applications include particle manipulation and trapping, in which a pressure field is produced using a highly focused US probe that can move or trap particles [17][18][19][20], drug delivery [21], elastography of muscles and tissues [22] and high-intensity focused US (HIFU), which involves high energy US waves producing heat in specific point in tissue to destroy cells [23], increase of blood flow and applications like face lifting [24,25] and pain management [26]. There are also many low-frequency applications such as ultrasonic scalps for surgery [27].…”

Incorporating Planar Folded Front Masses in Bolted Langevin-Style Transducers for Minimally Invasive Surgery

“…Previously, Khalaji et al [5] has interfaced an EndoWristlike ultrasonic scalpel with a stepped horn. The transducer was optimised using numerical techniques about 50 kHz, compared to 55 kHz operating frequency of the Harmonic ACE ® , and with 40 µm of tip vibration amplitude at 40 V pk of voltage input..Furthermore, Li et al [6] optimised an EndoWrist-like ultrasonic scalpel with a stepped structure front mass using finite element modelling, DOE and response surface method (RSM) and multi-objective genetic algorithm (MOGA) techniques.The optimised design generates a tip vibration amplitude about 60 µm, at 40 V pk , at 55.2 kHz operating frequency, and the tip vibration amplitude could reach 135 µm at 100 V pk . However, the tip temperature was not considered in both articles.…”

Investigation of the nonlinear phenomena of a Langevin ultrasonic transducer caused by high applied voltage

“…In recent years, the application of ultrasound technology has penetrated into various fields, 1 such as ultrasonic cleaning, 2 ultrasonic processing, 3,4 nondestructive testing, 5 and ultrasound medicine. 6,7 To promote ultrasound technology, the use of an ultrasonic transducer as the core component of ultrasonic devices and equipment has been a research hotspot. The Langevin ultrasonic transducer (LUT) has been widely used in precision engineering, 8,9 biomedical engineering, 10 robotics, 11 and other fields because of its compact structure, fast response, and high energy conversion efficiency.…”