Design of a Multifunctional Compliant Instrument for Minimally Invasive Surgery

2005 ◽  
Vol 127 (6) ◽  
pp. 990-993 ◽  
Author(s):  
Mary I. Frecker ◽  
Katherine M. Powell ◽  
Randy Haluck
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanism ◽  
Tissue Injury ◽  
Optimized Design ◽  
Jaw Opening ◽  
Multifunctional Device ◽  
Grasping Force ◽  
Length Width

A new multifunctional compliant instrument has been designed for use in minimally invasive surgery. The instrument combines scissors and forceps into a single multifunctional device. The main advantage of using multifunctional instruments for minimally invasive surgery is that instrument exchanges can be reduced, thus reducing procedure time and risk of inadvertent tissue injury during instrument exchanges. In this paper, the length, width, and thickness of the multifunctional compliant mechanism tool tip is optimized to maximize the jaw opening and the grasping force. The optimized design is then modeled to simulate the stresses encountered in the scissors mode. A 5.0mm diameter stainless steel prototype is fabricated using electro-discharge machining and is shown to grasp and cut successfully.

Size and Shape Optimization of a 1.0mm Multifunctional Forceps-Scissors Instrument for Minimally Invasive Surgery

2007 ◽  
Author(s):  
Milton E. Aguirre ◽  
Mary Frecker
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Shape Optimization ◽  
Invasive Surgery ◽  
Optimization Problems ◽  
Compliant Mechanism ◽  
Linear Deformation ◽  
Cross Sectional ◽  
Size And Shape ◽  
Grasping Forces

A size and shape optimization routine is developed and implemented on a 1 mm multifunctional instrument for minimally invasive surgery. The instrument is a compliant mechanism, without hinges, capable of both grasping and cutting. Multifunctional instruments have proven to be beneficial in the operating room because of their ability to perform multiple tasks, thereby decreasing the total number of instrument exchanges in a single procedure. In addition, with fewer exchanges the risk of inadvertent tissue trauma as well as overall surgical time and costs are reduced. The focus of the paper is to investigate the performance effects of allowing the cross-sectional area along the length of the device to vary. This is accomplished by defining various cross-sectional segments along the device in terms of parametric variables (Wi) and optimizing the dimensions to provide a sufficient forceps jaw opening while maintaining adequate cutting and grasping forces. Two optimization problems are considered. First, all parametric segments are set equal to one another permitting all cross-sections to vary uniformly and achieving size optimization. Second, each segment is defined as a separate design variable to allow segments to vary independently and thereby achieving shape optimization. Due to the device’s symmetry, one-half of the mechanism is modeled as a cantilever beam undergoing large deformation. ANSYS’ optimization module is employed using the first order method because it is capable of performing optimization considering non-linear deformation and multiple loading conditions. Finally, prototypes are fabricated using wire EDM and prototype evaluations are conducted to compare size versus shape optimization, and to validate ANSYS as the solution method.

Foldable Surgical Stereo Microendoscope With Continuously Adjustable Convergence

2012 ◽  
Vol 6 (1) ◽  
Author(s):  
Matteo Zoppi ◽  
Paolo Trifiletti ◽  
Rezia Molfino
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanism ◽  
Outer Diameter ◽  
Single Camera ◽  
Convergence Angle ◽  
Optical Axes

The paper presents a new design of a stereo endoscope for minimally invasive surgery with: cameras positioned at the tip of the instrument (inside the patient), angle of convergence of the optical axes of the cameras variable continuously, and a foldable mechanism reducing the outer diameter of the endoscope to almost the diameter of the single camera in order to reduce the size of the insertion port. After the insertion the endoscope is deployed and the two cameras move side by side. A very simple compliant mechanism is used to drive the deployment and the adjustment of the convergence angle.

scholarly journals Design of a novel tendon-driven manipulator structure based on monolithic compliant rolling-contact joint for minimally invasive surgery

2021 ◽  
Author(s):  
Dingzhi Zhang ◽  
Yilun Sun ◽  
Tim C. Lueth
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Tissue Injury ◽  
Rolling Contact ◽  
Element Analysis ◽  
Bending Angle ◽  
Contact Joint ◽  
Compliant Joint ◽  
Contact Mechanism

Abstract Purpose Compliant mechanisms are commonly used in the design of manipulator and surgical robotic tools for minimally invasive surgery (MIS) thanks to their compactness, ability of miniaturization and lower part count. However, conventional compliant joint has higher internal stiffness, which limits the bending radius. To overcome this problem, a novel tendon-driven manipulator structure based on monolithic compliant rolling-contact joint (CRCJ) is proposed. Methods The proposed rolling-contact mechanism is used to prevent cable slack during actuation, which occurs in conventional compliant joint design. By means of selective laser sintering (SLS) technique, the CRCJ can be fabricated in a monolithic structure, thus granting the CRCJ both the advantages of compliant joints and rolling-contact mechanism. Simulations with nonlinear finite element analysis (FEA) and experiments were conducted to evaluate and compare the mechanical properties of the proposed CRCJ with conventional leaf-type compliant joint including the bending and compliant motion. Results Experimental results showed that the CRCJ has lower bending stiffness, higher maximum bending angle (over $$180^{\circ }$$ 180 ∘ ) and a higher compliance compared to conventional compliant hinges, which allows a larger workspace and reduces the possibility of tissue injury. Agreement was also found between the nonlinear FEA and experiments regarding the relation between actuation force and bending angle. A primary prototype of a 3-DOF handheld laparoscopic manipulator with a diameter of 7 mm was further developed. Conclusion A dexterous tendon-driven monolithic manipulator structure based on CRCJ for MIS is proposed. A preliminary prototype of a handheld laparoscopic manipulator demonstrates the capability of the CRCJ for steerable medical devices. However, design improvements based on FEA and application-orientated prototypes considering anatomical requirements still show room for improvements.

Automatic synthesis of compliant forceps for robot-assisted minimally invasive surgery

2020 ◽  
Vol 68 (11) ◽  
pp. 922-932
Author(s):  
Yilun Sun ◽  
Lingji Xu ◽  
Dingzhi Zhang ◽  
Tim C. Lueth
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanism ◽  
Synthesis Method ◽  
Robot Assisted ◽  
Automatic Synthesis ◽  
Geometry Modeling ◽  
3D Printed ◽  
Monolithic Structure

AbstractDue to its monolithic structure and high dexterity, the compliant mechanism becomes an emerging solution to miniaturize surgical forceps for minimally invasive procedures. However, it is complicated and inefficient to use traditional rigid-link-based kinematic method to synthesize compliant forceps. In this paper, we present a topology-optimization-based method to automatically synthesize compliant forceps for robot-assisted minimally invasive surgery (RMIS). The basic geometry modeling tool and the automatic synthesis algorithm were both implemented in Matlab. Several synthesis examples were presented to show the performance of the proposed method. The realized forceps and a continuum manipulator have been constructed and 3D-printed, which demonstrated the application of the automatic synthesis method in RMIS.

scholarly journals A randomized 500-subject open-label phase 3 clinical trial of minimally invasive surgery plus alteplase in intracerebral hemorrhage evacuation (MISTIE III)

2019 ◽  
Vol 14 (5) ◽  
pp. 548-554 ◽  
Author(s):  
Wendy C Ziai ◽  
Nichol McBee ◽  
Karen Lane ◽  
Kennedy R Lees ◽  
Jesse Dawson ◽  
...  
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Intracerebral Hemorrhage ◽  
Invasive Surgery ◽  
Tissue Injury ◽  
Surgical Removal ◽  
Open Label ◽  
Phase 3 ◽  
Patient Disposition ◽  
Open Label Phase

Rationale and hypothesisSurgical removal of spontaneous intracerebral hemorrhage may reduce secondary destruction of brain tissue. However, large surgical trials of craniotomy have not demonstrated definitive improvement in clinical outcomes. Minimally invasive surgery may limit surgical tissue injury, and recent evidence supports testing these approaches in large clinical trials.Methods and designMISTIE III is an investigator-initiated multicenter, randomized, open-label phase 3 study investigating whether minimally invasive clot evacuation with thrombolysis improves functional outcomes at 365 days compared to conservative management. Patients with supratentorial intracerebral hemorrhage clot volume ≥ 30 mL, confirmed by imaging within 24 h ofknown symptom onset,and intact brainstem reflexes were screened with a stability computed tomography scan at least 6 h after diagnostic scan. Patients who met clinical and imaging criteria (no ongoing coagulopathy; no suspicion of aneurysm, arteriovenous malformation, or any other vascular anomaly; and stable hematoma size on consecutive scans) were randomized to either minimally invasive surgery plus thrombolysis or medical therapy. The sample size of 500 was based on findings of a phase 2 study.Study outcomesThe primary outcome measure is dichotomized modified Rankin Scale 0–3 vs. 4–6 at 365 days adjusting for severity variables. Clinical secondary outcomes include dichotomized extended Glasgow Outcome Scale and all-cause mortality at 365 days; rate and extent of parenchymal blood clot removal; patient disposition at 365 days; efficacy at 180 days; type and intensity of ICU management; and quality of life measures. Safety was assessed at 30 days and throughout the study.

scholarly journals Inverted L-Arm Gripper Compliant Mechanism

2017 ◽  
Vol 11 (3) ◽  
Author(s):  
Jason Dearden ◽  
Clayton Grames ◽  
Brian D. Jensen ◽  
Spencer P. Magleby ◽  
Larry L. Howell
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanisms ◽  
Compliant Mechanism ◽  
Mechanical Advantage ◽  
Bending Stresses ◽  
Materials Used ◽  
Work First ◽  
Two Degree Of Freedom

This work exploits the advantages of compliant mechanisms (devices that achieve their motion through the deflection of flexible members) to enable the creation of small instruments for minimally invasive surgery (MIS). Using flexures to achieve motion presents challenges, three of which are considered in this work. First, compliant mechanisms generally perform inadequately in compression. Second, for a ±90deg range of motion desired for each jaw, the bending stresses in the flexures are prohibitive considering materials used in current instruments. Third, for cables attached at fixed points on the mechanism, the mechanical advantage will vary considerably during actuation. Research results are presented that address these challenges using compliant mechanism principles as demonstrated in a two-degree-of-freedom (2DoF) L-Arm gripper.

Design of a 1.0mm Multifunctional Forceps-Scissors Instrument for Minimally Invasive Surgery

2006 ◽  
Author(s):  
Milton E. Aguirre ◽  
Mary Frecker
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanism ◽  
Rectangular Cross Section ◽  
Geometric Constraints ◽  
Element Analysis ◽  
Performance Space

A multifunctional forceps-scissors instrument is designed for minimally invasive surgery. The device is a compliant mechanism capable of both grasping and cutting. The focus of the paper is on the design optimization and a detailed finite element analysis of the compliant mechanism. One-half of the symmetric compliant mechanism is modeled as a cantilever beam of rectangular cross-section undergoing large deformation. The optimization problem is solved graphically where all feasible designs (i.e., those that satisfy the stress and geometric constraints) are displayed on performance space plots. Using this method it is easy to visualize the performance space and to select a suitable design; however, it is found that it is not possible to simultaneously maximize free deflection and blocked force in the forceps or scissors modes. A detailed finite element analysis was conducted using ANSYS to model the multiple loading conditions. A prototype instrument, fabricated from stainless steel using wire EDM with the precision of +/- 2 μm, has been tested for comparison of actual and predicted results.

Modeling and Design of a Piezoelectric Forceps Actuator for Meso∕Micro Grasping

2006 ◽  
Vol 1 (1) ◽  
pp. 30-37 ◽  
Author(s):  
Ken Susanto ◽  
Bingen Yang
Keyword(s):  
Genetic Algorithm ◽  
Mathematical Model ◽  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Significant Role ◽  
Invasive Surgery ◽  
Biological Tissues ◽  
Soft Objects ◽  
Grasping Force ◽  
Relationship Of

Meso∕micro grasping of tiny soft objects such as biological tissues, which ranges from hundreds to thousands of micro-millimeters in dimension, plays a significant role in the fields of tele-surgery, minimally invasive surgery (MIS), and biomedical instrumentation. Recently, the authors proposed a novel piezoelectric forceps actuator (PFA), which is capable of grasping delicate soft objects. One of the advantages of the PFA over conventional MIS forceps lies in that it can be remotely controlled to achieve precision deflection and grasping force. Furthermore, it does not have any moving parts such as gears and hinges, and hence avoids problems in operation like friction, backlash, lubrication, leakage, and sterilization. In this paper, a mathematical model of the PFA is derived, based on which genetic algorithm (GA) is applied to optimize the grasping force-deflection relationship of the actuator. The model developed is experimentally verified on a prototype of the PFA.

Kinematic Representations of Pop-Up Paper Mechanisms

2007 ◽  
Author(s):  
Brian G. Winder ◽  
Spencer P. Magleby ◽  
Larry L. Howell
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Compliant Mechanism ◽  
Deployable Structures ◽  
Kinematic Chains ◽  
Paper Folding ◽  
The Creation ◽  
Complex Mechanisms ◽  
Double Slit

Pop-up paper mechanisms use techniques very similar to the well-studied paper folding techniques of origami. However, popups differ in both the manner of construction and the target uses, warranting further study. This paper outlines the use of planar and spherical kinematics to model commonly used pop-up paper mechanisms. A survey of common joint types is given, including folds, interlocking slots, bends, pivots, sliders and rotating sliders. Also included is an overview of common onepiece and layered mechanisms, including single-slit, double-slit, V-fold, tent, tube strap and arch mechanisms. Each mechanism or joint is described using a kinematic or compliant mechanism representation. In addition, it is shown that more complex mechanisms may be created by combining simple mechanisms in various ways. The principles presented are applied to the creation of new pop-up joints and mechanisms. The new mechanisms employ both spherical and spatial kinematic chains. Various other applications are also mentioned which could benefit from the use of pop-up mechanism principles. Possible applications include deployable structures, packaging and instruments for minimally invasive surgery.

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