著者

川嶋 健嗣 只野 耕太郎

出版者

耳鼻咽喉科展望会

雑誌

耳鼻咽喉科展望 (ISSN:03869687)

巻号頁・発行日

vol.55, no.5, pp.359-363, 2012-10-15 (Released:2013-10-15)

参考文献数

3

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Recently, increasing emphasis on quality-of-life issues in surgery such as relieving patient pain, reducing scarring, and shortening hospital stays has led to wider use of endoscopic surgery. In endoscopic surgery, forceps and other instruments are inserted through a hole made in the abdomen of the patient, and surgery is performed through visualization of the endoscopic image. Though this technique presents a lower burden to the patient than laparoscopic surgery, manipulation of instruments through the insertion hole used as a fulcrum complicates a free approach to the surgical target and demands advanced skills of surgeons.Consequently, there is active research on free movement of instrument tips through robotics technology in order to alleviate the burden on the physician. As commercialized in the well-known “da Vinci” system, these devices employ a master-slave system comprising a master console operated by the physician, and patient-side slave instruments manipulated after insertion into the body of the patient. The system allows remote procedures providing the sensation that one's own hands are located in the body. However, current master-slave systems operate solely through reliance on image data from an endoscopic camera, and development of devices allowing safer operation is needed. What is particularly desired is a system that senses contact or force at the slave-side instrument and delivers this information to the physician at the master console. However, practical considerations such as compactness and sterility make it undesirable to attach force sensors to forceps for observational purposes. Currently, the patient-side equipment is also driven by electromechanical motors. In such a context, we have worked on the development of a master slave robotic system for laparoscopic surgery with 7-DOFs. In this system, pneumatic actuators, instead of electric motors, are used to detect external forces based on pressure values without a force sensor. This approach reduces costs and sterilizability demands for forceps manipulator while enable haptic feedback to the surgeons. We have prototyped a model of surgical manipulators named IBIS for its resemblance to the bird which has high performance in the estimation of external force. We evaluated its performance in terms of force estimation. The forces acting on a joint are estimated during contact with the external environment. Our technical assist system is designed to deliver positioning commands from the master side to the slave side via the internet, estimate contact force at slave-side instrument tips based on the pressure differential with the pneumatic cylinder, and convey this information to the master side. The experimental results indicate that IBIS estimates external forces with a sensitivity of 0.5 N. We also conduct an in vivo experiment and confirm the effectiveness and improvement of the manipulator. Currently, through cooperation with Tokyo Medical and Dental University, animal experiments are ongoing to evaluate the efficacy of the system developed and to continue its improvement.