Kitano Sousaku, Komatsuzaki Toshihiko, Suzuki Ikuto, Nogawa Masamichi, Naito Hisashi, Tanaka Shinobu
Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Japan.
Department of Clinical Engineering, Faculty of Health Sciences, Komatsu University, Komatsu, Japan.
Front Robot AI. 2020 Apr 28;7:59. doi: 10.3389/frobt.2020.00059. eCollection 2020.
Laparoscopic surgery is a representative operative method of minimally invasive surgery. However, most laparoscopic hand instruments consist of rigid and straight structures, which have serious limitations such as interference by the instruments and limited field of view of the endoscope. To improve the flexibility and dexterity of these instruments, we propose a new concept of a multijoint manipulator using a variable stiffness mechanism. The manipulator uses a magneto-rheological compound (MRC) whose rheological properties can be tuned by an external magnetic field. In this study, we changed the shape of the electromagnet and MRC to improve the performance of the variable stiffness joint we previously fabricated; further, we fabricated a prototype and performed basic evaluation of the joint using this prototype. The MRC was fabricated by mixing carbonyl iron particles and glycerol. The prototype single joint was assembled by combining MRC and electromagnets. The configuration of the joint indicates that it has a closed magnetic circuit. To examine the basic properties of the joint, we conducted preliminary experiments such as elastic modulus measurement and rigidity evaluation. We confirmed that the elastic modulus increased when a magnetic field was applied. The rigidity of the joint was also verified under bending conditions. Our results confirmed that the stiffness of the new joint changed significantly compared with the old joint depending on the presence or absence of a magnetic field, and the performance of the new joint also improved.
腹腔镜手术是微创手术的一种代表性手术方法。然而，大多数腹腔镜手持器械由刚性和笔直的结构组成，存在诸如器械干扰和内窥镜视野受限等严重局限性。为了提高这些器械的灵活性和灵巧性，我们提出了一种使用可变刚度机制的多关节机械手的新概念。该机械手使用一种磁流变复合材料（MRC），其流变特性可通过外部磁场进行调节。在本研究中，我们改变了电磁铁和MRC的形状，以改善我们之前制造的可变刚度关节的性能；此外，我们制造了一个原型，并使用该原型对关节进行了基本评估。MRC是通过将羰基铁颗粒和甘油混合制成的。原型单关节是通过将MRC和电磁铁组合组装而成的。关节的结构表明它具有闭合磁路。为了研究关节的基本特性，我们进行了诸如弹性模量测量和刚度评估等初步实验。我们证实，施加磁场时弹性模量会增加。在弯曲条件下也验证了关节的刚度。我们的结果证实，与旧关节相比，新关节的刚度根据磁场的有无而有显著变化，并且新关节的性能也有所提高。
