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11:06
Design and Fabrication of an Elastomeric Unit for Soft Modular Robots in Minimally Invasive Surgery
Published on: November 14, 2015
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Optimizing Tube Precurvature to Enhance Elastic Stability of Concentric Tube Robots
Junhyoung Ha1, Frank C Park2, Pierre E Dupont3
1Department of Cardiovascular Surgery, Boston Childrens Hospital, Harvard Medical School, Boston, MA 02115 USA.
IEEE Transactions on Robotics : a Publication of the IEEE Robotics and Automation Society
|October 3, 2017
Summary
Robotic instruments using concentric tube technology can improve surgical precision. Optimizing tube precurvature enhances stability and control for minimally invasive procedures.
Area of Science:
- Robotics
- Mechanical Engineering
- Medical Devices
Background:
- Concentric tube robots offer advantages for minimally invasive surgery due to their slender profiles and ability to navigate complex anatomical spaces.
- Elastic instabilities can occur during the operation of these robots, particularly when rotating precurved tubes, limiting their performance and safety.
- Previous designs focused on constant precurvature, restricting the potential for advanced maneuverability and stability.
Purpose of the Study:
- To investigate the impact of varying precurvature along the arc length of concentric tubes on robotic instrument stability.
- To develop an optimal design formulation for concentric tube robots that maximizes stability and control.
- To enhance the range of motion and safety of robotic instruments for minimally invasive applications.
Main Methods:
- Derived stability conditions for planar concentric tube pairs with continuously varying precurvature.
- Formulated an optimal design problem to determine the ideal precurvature function.
- Incorporated straight transmission segments at the proximal ends of the tubes into the design formulation.
- Validated the analytical results through numerical simulations and physical experiments.
Main Results:
- Demonstrated that continuously varying precurvature significantly enhances stability compared to constant precurvature designs.
- Developed an analytic formulation for optimal precurvature that balances tip orientation range, stability, and bending strain limits.
- Confirmed the effectiveness of the proposed design approach through experimental validation.
- Achieved enhanced stability and control in robotic instruments with variable precurvature designs.
Conclusions:
- Variable precurvature offers a significant advantage in improving the stability and maneuverability of concentric tube robotic instruments.
- The developed analytical formulation provides a robust method for designing more stable and capable robotic surgical tools.
- This research paves the way for next-generation robotic instruments with superior performance in minimally invasive surgery.
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