[6] Damian D. Marucci, John A. Cartmill, William R. Walsh, and Christopher J. Martin, âPatterns of Failure at the InstrumentâTissue Interface,â Journal of Surgical ...
DA VINCI SHAPE MEMORY ALLOY GRASPER TEAM 4Ceps ABDUL HAMID MERII
Nivethitha Shanmuganathan
Background
Rodrigo Carrilho
Control & Sensing
Minimally Invasive Surgery (MIS)
Material Properties of Flexinol
Involves the use of small incisions through which long thin surgical tools and a camera are placed inside a patient’s body. The camera can record 360° capture of the area of interest [1]. Advantages:
The grasper is actuated by using flexinol, which is a type of shape memory alloy capable of shrinking by up to 4% of its original length when heated to a certain transformation temperature. Flexinol’s length can be controlled by varying it’s temperature between the 𝐴𝑠 & 𝐴𝑓 temperatures shown in figure 1. Figure 2 shows how the material resistance of flexinol is affected by the amount of stress applied.
• Less Pain • Faster Recovery • Less Blood Loss
Harrison Edokpola
Control & Non-Intrusive Sensing The rotation of the disc is detected by the potentiometer shown in figure 3 and translated to a corresponding resistance 𝑅𝑃 . The flexinol wire is then heated by passing a current through it and the material resistance 𝑅𝑀 & temperature of the flexinol wire is then measured (figure 3). The amount of stress exerted by the flexinol can be determined by calibrating the microcontroller using discrete values as shown in figure 2. The stress obtained is fed back to the console where haptic feedback is implemented using magnetorheological fluid [8].
• Smaller Scars
Robotic Laparoscopic Surgery Advantages:
Gecko Inspired Grasper Design
• Reduces Stress on Surgeon • Motion Scaling for Increased Accuracy • Capable of Teleoperation
Disadvantages:
Figure 2 [7]
Figure 1 [7]
• Absence of Force & Haptic Feedback • Increased Potential for Tissue Damage
[2] [3]
Tissue Damage by Surgical Graspers Tissue damage is mostly attributed to grasper design. A slight difference in mechanical stress is sufficient to damage the tissue. Solutions: • Force Sensing & Feedback • Tissue Oxidation Sensing
Works Cited
• Suitable Grasper Design
[1] Smita De , “The Grasper-Tissue Interface in Minimally Invasive Surgery: Stress and Acute Indicators of Injury,” dissertation, 2008. [2] B. T. Bethea, A. M. Okamura, M. Kitagawa, T. P. Fitton, S. M. Cattaneo, V. L. Gott, W. A. Baumgartner, and D. D. Yuh, "Application of haptic feedback to robotic surgery," J. Laparoendosc. Adv. Surg. Tech. A, vol. 14, no. 3, pp. 191-195, June2004. [3] J. Bodner, H. Wykypiel, G. Wetscher, and T. Schmid, "First experiences with the da Vinci operating robot in thoracic surgery," Eur. J. Cardiothorac. Surg., vol. 25, no. 5, pp. 844-851, May2004 [4] Gregory S. Fischer, Takintope Akinbiyi, Sunipa Saha, Jason Zand, Mark Talamini, Michael Marohn, and Russell Taylor, “International Conference on Biomedical Robotics and Biomechatronics (BioRob) ,” 2006. [5] L. Cheng and B. Hannaford, “Evaluation of liver tissue damage and grasp stability using finite element analysis,” Computer Methods in Biomechanics and Biomedical Engineering, vol. 19, no. 1, pp. 31–40, 2014. [6] Damian D. Marucci, John A. Cartmill, William R. Walsh, and Christopher J. Martin, “Patterns of Failure at the Instrument–Tissue Interface,” Journal of Surgical Research, Sep. 2000. [7] H. Song, E. Kubica, and R. Gorbet, “Resistance Modelling of Sma Wire Actuators,” Aerospace, no. November, 2011.. [8] Teppei Tsujita, Kazuya Sase, Atsushi Konno, Masano Nakayama, XiaoShuai Chen, Koyu Abe and Masaru Uchiyama, Design and Evaluation of an Encountered-type Haptic Interface Using MR fluid for Surgical Simulators, Advanced Robotics (AR), Taylor & Francis, vol. 27, no. 7, pp. 525-540, April 2, 2013
[4] [5] [6]
Figure 3
