Modeling and Design of a Piezoelectric Forceps Actuator for Meso∕Micro Grasping

Abstract

Meso∕micro grasping of tiny soft objects such as biological tissues, which ranges from hundreds to thousands of micro-millimeters in dimension, plays a significant role in the fields of tele-surgery, minimally invasive surgery (MIS), and biomedical instrumentation. Recently, the authors proposed a novel piezoelectric forceps actuator (PFA), which is capable of grasping delicate soft objects. One of the advantages of the PFA over conventional MIS forceps lies in that it can be remotely controlled to achieve precision deflection and grasping force. Furthermore, it does not have any moving parts such as gears and hinges, and hence avoids problems in operation like friction, backlash, lubrication, leakage, and sterilization. In this paper, a mathematical model of the PFA is derived, based on which genetic algorithm (GA) is applied to optimize the grasping force-deflection relationship of the actuator. The model developed is experimentally verified on a prototype of the PFA.

Modelling, vibration analysis and feedback control of a piezoelectric forceps actuator

“…The material and the physical properties of the PFA are listed in Table 1. The displacement and the grasping force models of the PFA have been studied by the authors (Susanto and Yang 2007) and it is found from the experiments that the level of grasping force is 124 mN at 300 V. Due to the nature of relatively slow motion of the PFA in fine grasping, a pre-cursor experiment reveals that the dynamic response of the beam can be characterised in a frequency range under 20 Hz. For this reason, the first three modes of vibration of the beam are of primary interest.…”

“…A schematic of the PFA in consideration is seen in Figure 1. The PFA can produce reasonable deflection and meso/ micro grasping force for picking up a very thin wire through the narrow small diameter beaker (Susanto and Yang 2004a, Susanto 2007, Susanto and Yang 2007. The actuator does not contain complicated parts like hinges, rack and pinion, gears and motor, and hence does not have mechanical backlash, and requires less maintenance.…”

Vibration analysis of piezoelectric laminated slightly curved beams using distributed transfer function method

“…Rapid developments in intelligent biomedical devices using piezoelectric laminated slightly curved beams (PLSCB) actuators have been proposed, which include a piezoelectric cell stretching device (Clark et al, 2000), a stimulator for cultured bone cells (Tanaka, 1999), a device for straining flexible cell culture membranes (Schaffer et al, 1994) and a novel piezoelectric forceps actuator for minimum invasive surgery (Susanto and Yang, 2004;Susanto and Yang, 2007;Susanto, 2008). Furthermore, the piezoelectric actuators also have been used in controlling the shape of the satellite antenna (Washington, 1996;Granger et al, 2000) and damping of wings (Crawley and de Luis, 1987).…”

Analysis of finite deformation of curved beams bonded with piezoelectric actuating layers

“…Laminated composite beams have been popular and widely applied in many practical fields over the past few decades. Rapid developments of intelligent micro-electromechanical systems (MEMS), such as smart biomedical devices, using piezoelectric laminated curved beams (PLCB), have been proposed (Clark et al, 2000; Karami et al, 2010; Schaffer et al, 1994; Susanto, 2008; Susanto and Yang, 2007; Tanaka, 1999; Zhang et al, 2015). Currently, piezoelectric elements are one of the most popular and widely available elements to be used in smart structure applications.…”