Force sensing based on string vibration for multi degree-of-freedom forceps

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K21940
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 20:Mechanical dynamics, robotics, and related fields
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Omata Toru 東京工業大学, 工学院, 教授 (10262312)
• Project Period (FY): 2019-06-28 – 2024-03-31
• Keywords: 知能機械 / 手術ロボット

Outline of Final Research Achievements

This study challenged the difficult problem of force sensing of surgical robotic forceps by measuring the cable tensions by string vibration. The proposed method is applicable to cable driven forceps. It induces vibration of the drive cables with a rotating protrusion; estimates the cable tension from the vibration frequency, and then estimates the external force applied to the forceps. An experimental device was developed and a satisfactory accuracy of the tension measurement was verified. The study also developed three degree-of-freedom forceps and verified the accuracy of the contact force measurement. The physical contact between the cable and protrusion caused wear of them. The amount of wear was measured after the cable was plucked one million times assuming one million plucks during one operation. The result showed that the wear was minimal and not problematic for practical use.

Free Research Field

機械工学

Academic Significance and Societal Importance of the Research Achievements

腹腔鏡手術などに使われる手術ロボット屈曲鉗子に力センシング機能を付与することが安全で高度な手術の実施のために望まれている．しかし，小型化が難しいこと，著しく過酷な体内環境での使用に耐えられる必要があり，さらに，洗浄滅菌可能であること，頑健であること，低コストであることが要求されるため極めて難しく，依然として未完成である．これまでのほとんどの方法では，力を歪に変換する起歪体を用いているが，壊れやすく高価になることが大きな欠点である．本研究の学術的意義は，起歪体を用いないユニークな方法を提案したことであり，社会的意義は，手術ロボット屈曲鉗子の力センシングという難問の一解決法を示したことである．