Smart Structure and Systems Laboratory, Department of Mechanical Engineering, Inha University, Incheon 22212, Korea.
Department of Mechanical Engineering, The State University of New York, Korea (SUNY Korea), Incheon 21985, Korea.
Sensors (Basel). 2021 Apr 26;21(9):3034. doi: 10.3390/s21093034.
This paper proposes a new type of tactile transfer cell which can be effectively applied to robot-assisted minimally invasive surgery (RMIS). The proposed tactile device is manufactured from two smart materials, a magnetorheological fluid (MRF) and a magnetorheological elastomer (MRE), whose viscoelastic properties are controllable by an external magnetic field. Thus, it can produce field-dependent repulsive forces which are equivalent to several human organs (or tissues) such as a heart. As a first step, an appropriate tactile sample is made using both MRF and MRE associated with porous foam. Then, the microstructures of these materials taken from Scanning Electron Microscope (SEM) images are presented, showing the particle distribution with and without the magnetic field. Subsequently, the field-dependent repulsive force of the sample, which is equivalent to the stress relaxation property of viscoelastic materials, are measured at several compressive deformation depths. Then, the measured values are compared with the calculated values obtained from Young's modulus of human tissue data via the finite element method. It is identified from this comparison that the proposed tactile transfer cell can mimic the repulsive force (or hardness) of several human organs. This directly indicates that the proposed MR materials-based tactile transfer cell (MRTTC in short) can be effectively applied to RMIS in which the surgeon can feel the strength or softness of the human organ by just changing the magnetic field intensity. In this work, to reflect a more practical feasibility, a psychophysical test is also carried out using 20 volunteers, and the results are analyzed, presenting the standard deviation.
本文提出了一种新型的触觉传递单元，可有效应用于机器人辅助微创手术（RMIS）。所提出的触觉装置由两种智能材料制成，即磁流变液（MRF）和磁流变弹性体（MRE），其粘弹性可通过外部磁场控制。因此，它可以产生与外部磁场相关的排斥力，其大小相当于几个人体器官（或组织），例如心脏。作为第一步，使用与多孔泡沫相关的 MRF 和 MRE 制作出合适的触觉样本。然后，展示了从扫描电子显微镜（SEM）图像中获取的这些材料的微观结构，显示了在有磁场和无磁场情况下的颗粒分布。随后，在几个压缩变形深度下测量了样本的磁场相关排斥力，该力等效于粘弹性材料的应力松弛特性。然后，将测量值与通过有限元法从人体组织数据获得的杨氏模量的计算值进行比较。通过比较可以看出，所提出的触觉传递单元可以模拟几个人体器官的排斥力（或硬度）。这直接表明，所提出的基于 MR 材料的触觉传递单元（简称 MRTTC）可有效应用于 RMIS，外科医生只需改变磁场强度即可感受到人体器官的强度或柔软度。在这项工作中，为了反映更实际的可行性，还使用 20 名志愿者进行了心理物理测试，并对结果进行了分析，给出了标准偏差。
