0
Research Papers

Utilization of Cable Guide Channels for Compact Articulation Within a Dexterous Three Degrees-of-Freedom Surgical Wrist Design

[+] Author and Article Information
Dale J. Podolsky

University of Toronto,
The Hospital for Sick Children,
5430-555 Hill Wing,
University Avenue,
Toronto, ON M5G 1X8, Canada
e-mail: dale.podolsky@mail.utoronto.ca

Eric Diller

Mem. ASME
Department of Mechanical
and Industrial Engineering,
University of Toronto,
5 King's College Road, MC310,
Toronto, ON M5S 3G8, Canada
e-mail: ediller@mie.utoronto.ca

David M. Fisher

University of Toronto,
The Hospital for Sick Children,
5430-555 Hill Wing,
University Avenue,
Toronto, ON M5G 1X8, Canada
e-mail: david.fisher@utoronto.ca

Karen W. Wong Riff

University of Toronto,
The Hospital for Sick Children,
5418-555 Hill Wing,
University Avenue,
Toronto, ON M5G 1X8, Canada
e-mail: karenw.wong@sickkids.ca

Thomas Looi

University of Toronto,
The Hospital for Sick Children,
7142-555 Burton Wing,
University Avenue,
Toronto, ON M5G 1X8, Canada
e-mail: thomas.looi@sickkids.ca

James M. Drake

University of Toronto,
The Hospital for Sick Children,
1504-555 Hill Wing,
University Avenue,
Toronto, ON M5G 1X8, Canada
e-mail: james.drake@sickkids.ca

Christopher R. Forrest

University of Toronto,
The Hospital for Sick Children,
5430-555 Hill Wing,
University Avenue,
Toronto, ON M5G 1X8, Canada
e-mail: christopher.forrest@sickkids.ca

Manuscript received April 4, 2018; final manuscript received September 19, 2018; published online November 19, 2018. Assoc. Editor: Carl Nelson.

J. Med. Devices 13(1), 011003 (Nov 19, 2018) (11 pages) Paper No: MED-18-1066; doi: 10.1115/1.4041591 History: Received April 04, 2018; Revised September 19, 2018

Pin-jointed wrist mechanisms provide compact articulation for surgical robotic applications, but are difficult to miniaturize at scales suitable for small body cavity surgery. Solid surface cable guide channels, which eliminate the need for pulleys and reduce overall length to facilitate miniaturization, were developed within a three-degree-of-freedom cable-driven pin-jointed wrist mechanism. A prototype was 3D printed in steel at 5 mm diameter. Friction generated by the guide channels was experimentally tested to determine increases in cable tension during constant cable velocity conditions. Cable tension increased exponentially from 0 to 37% when the wrist pitched from 0 deg to 90 deg. The shape of the guide channel groove and angle, where the cable exits the channel impacts the magnitude of cable tension. A spring tensioning and cam actuation mechanism were developed to account for changing cable circuit path lengths during wrist pitch. This work shows that pulley-free cable wrist mechanisms can facilitate miniaturization below current feasible sizes while retaining compact articulation at the expense of increases in friction under constant cable velocity conditions.

Copyright © 2019 by ASME
Your Session has timed out. Please sign back in to continue.

References

Selber, J. C. , Sarhane, K. A. , Ibrahim, A. E. , and Holsinger, F. C. , 2014, “ Transoral Robotic Reconstructive Surgery,” Semin. Plast. Surg., 28(1), pp. 35–38. [CrossRef] [PubMed]
Leonardis, R. L. , Duvvuri, U. , and Mehta, D. , 2014, “ Transoral Robotic-Assisted Laryngeal Cleft Repair in the Pediatric Patient,” Laryngoscope, 124(9), pp. 2167–2169. [CrossRef] [PubMed]
Podolsky, D. J. , Fisher, D. M. , Wong Riff, K. W. , Looi, T. , Drake, J. M. , and Forrest, C. R. , 2017, “ Infant Robotic Cleft Palate Surgery: A Feasibility Assessment Using a Realistic Cleft Palate Simulator,” Plast. Reconstr. Surg., 139(2), pp. 455e–465e. [CrossRef] [PubMed]
Grames, C. L. , 2015, “ Design and Manufacture of Mesoscale Robot-Actuated Surgical Instruments,” Master's thesis, Brigham Young University, Provo, UT.
Jason Dearden, C. G. , Jensen, B. D. , Magleby, S. P. , and Howell, L. L. , 2017, “ Inverted L-Arm Gripper Compliant Mechanism,” ASME J. Med. Devices, 11(3), p. 034502. [CrossRef]
Catherine, J. , Rotinat-Libersa, C. , and Micaelli, A. , 2011, “ Comparative Review of Endoscopic Devices Articulations Technologies Developed for Minimally Invasive Medical Procedures,” Appl. Bionics Biomech., 8(2), pp. 151–171. [CrossRef]
Jelinek, F. , Arkenbout, E. A. , Henselmans, P. W. J. , Pessers, R. , and Breedveld, P. , 2015, “ Classification of Joints Used in Steerable Instruments for Minimally Invasive Surgery—A Review of the State of the Art,” ASME J. Med. Devices, 9(1), p. 010801.
Murphy, T. E. M. , and Nixon, M. M. ., 2013, “ Surgical Instrument Wrist,” Intuitive Surgical Inc., Sunnyvale, CA, U. S. Patent No. US8540748B2. https://patents.google.com/patent/US20100004663
Williams, M. R. , 2014, “ Instrument Wrist With Cycloidal Surfaces,” U. S. Patent No. US8887595B2. https://patents.google.com/patent/US20110152879
CSI, 2006, “Design Guide for Cable Solutions,” Sava Industries, Riverdale, NJ, pp. 1–38.
van Poelgeest, A. , Kahler, G. , and Magdeburg, R. , 2013, “ The Future of Notes (Natural Orifice Translumenal Endoscopic Surgery) Technology,” Biomed Technol. (Berl). (epub).
Burbank, W. A. , 2014, “ Four-Cable Wrist With Solid Surface Cable Channels,” Patent No. WO2010009221A2.
Gao, X. , Wang, L. , and Hao, X. , 2015, “ An Improved Capstan Equation Including Power-Law Friction and Bending Rigidity for High Performance Yarn,” Mech. Mach. Theory, 90, pp. 84–94. [CrossRef]
Podolsky, D. J. , Fisher, D. M. , Wong, K. W. , Looi, T. , Drake, J. M. , and Forrest, C. R. , 2017, “ Evaluation and Implementation of a High-Fidelity Cleft Palate Simulator,” Plast. Reconstr. Surg., 139(1), pp. 85e–96e. [CrossRef] [PubMed]
Rizos, D. D. , and Fassois, S. D. , 2009, “ Friction Identification Based Upon the LuGre and Maxwell Slip Models,” IEEE Trans. Control Syst. Technol., 17(1), pp. 153–160. [CrossRef]
Freidovich, L. , Robertsson, A. , Shiriaev, A. , and Johansson, R. , 2010, “ LuGre-Model-Based Friction Compensation,” IEEE Trans. Control Syst. Technol., 18(1), pp. 194–200. [CrossRef]
Daniel Ludwigsen, K. S. , 2009, “ Choose Wisely: Static or Kinetic Friction-The Power of Dimensionless Plots,” Phys. Teach., 47(3), pp. 158–161. [CrossRef]
Kessler, G. , 2009, “ Comments on Static versus Kinetic Friction,” Phys. Teach., 47(6), pp. 326–328. [CrossRef]
Trejos, A. L. , Patel, R. V. , and Naish, M. D. , 2010, “ Force Sensing and Its Application in Minimally Invasive Surgery and Therapy: A Survey,” Proc. Inst. Mech. Eng. Eng., 224(7), pp. 1435–1454.

Figures

Grahic Jump Location
Fig. 1

(a) Computer-aided design of new wrist mechanism illustrating four main links (1, 2, 3-1, and 3-2) with pitch, yaw, and grip motion. Roll motion is at the actuation mechanism proximally (b) link 1 with the inner channel (red) and the outer channel (blue) that guide cables to links 3-1 and 3-2.

Grahic Jump Location
Fig. 2

(a) Angle of the guide channels curves and (b) groove pattern at the channel exit comparing the inner to outer channels

Grahic Jump Location
Fig. 3

Free-body diagram of wrist links from (a) yaw and (b) pitch axis with resultant cable tensions given an external force at the wrist tip. Fext is the externally applied force, F1 and F2 are cable tensions pulling gripper links distal to cable guide channels (in this case F2 = 0), F3 is the force proximal to cable guide channels, L is the length of the grippers, r is the radius of grippers at yaw axis, θ is the yaw/grip angle, and ∅ is the pitch angle.

Grahic Jump Location
Fig. 4

Impact of friction coefficient and wrist pitch on cable tensions as a result of the cable guide channels

Grahic Jump Location
Fig. 5

Wrist mechanism 3D printed in 17-4PH stainless steel with cables routed through channels to respective links. (a) and (b) pitch axis views. (c) and (d) Yaw axis views.

Grahic Jump Location
Fig. 6

Comparison of the pitch-to-yaw axis workspace of the da Vinci: (a) 8 mm (b) 5 mm, and (c) new 5 mm wrist. (d) Size comparison of the three instruments demonstrating the small workspace of the new wrist.

Grahic Jump Location
Fig. 7

Experimental setup of friction testing apparatus, where θ represents the pitch angle. View is top-down.

Grahic Jump Location
Fig. 8

Close-up view of cable moving along the link guide channels illustrating the direction of movement comparing the testing scenario of pulling the cable versus “pushing” the cable

Grahic Jump Location
Fig. 9

(a) Cleft palate simulator. (b) DVRK instrument setup within the cleft palate simulator. Comparison of clearance between instrument shaft and mouth with the (c) new instrument, (d) 5 mm and (e) 8 mm EndoWrist instruments when touching the left palate with an orientation typical for a surgical maneuver. Notice the increased clearance between the new instrument shaft and oral cavity and the inability of the existing da Vinci instruments to access the edge of the palate without contacting the mouth.

Grahic Jump Location
Fig. 10

Comparison of percent increase in cable tension versus pitch angle using a 0.27 mm diameter cable and 200 g weight

Grahic Jump Location
Fig. 11

(a) Comparison of percent increase in cable tension versus pitch angle using a 0.54 mm diameter cable and (b) 200 g weight and (bottom) 1000 g weight

Grahic Jump Location
Fig. 12

Percent increase in cable tension versus pitch angle using a 0.54 mm diameter cable and 1000 g weight for (a) design 2 and (b) design 3

Grahic Jump Location
Fig. 13

Change in cable circuit path length as the wrist pitches

Grahic Jump Location
Fig. 14

(a) Spring tensioning actuation mechanism to ensure cable tension maintained and length changes during wrist pitch. (b) Cam tension control system illustrating the cams coupled to pitch control. As the pitch rotates, the cams rotate contacting the gripper cables.

Grahic Jump Location
Fig. 15

(a) Cable path length change as the wrist pitches and (b) cam with oblique outer perimeter dimensions that increase or decrease in exact accordance with the cable path length changes as the wrist pitches

Grahic Jump Location
Fig. 16

Free body diagram of rail cars 1 and 2 position impacting spring tension and rail car 1 angle. ΔX1 is the change in position of rail car 1, ΔX2 is the change in position of rail car 1, Tt is the cable tension, Ts is the spring tension, and θi is the angle of cable as a result of rail car 1 movement.

Grahic Jump Location
Fig. 17

Rail car 1 angle impact on spring length change during wrist pitch. The top position represents the initial position with the wrist fully pitched at 90 deg. At this position, the circuit length is the shortest. The bottom position represents the wrist in neutral, which extends the circuit path length by 1.99 mm. As a result, rail car 1 slides to the right by an amount Δ. θi is the initial rail car 1 carriage angle, hi is the initial cable distance, θf is the final rail car 1 carriage angle, and hf is the final cable distance.

Grahic Jump Location
Fig. 18

Delta (Δ) as a function of carriage angle

Tables

Errata

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In