Development of a Variable Stiffness Over Tube Based on Low-Melting-Point-Alloy for Endoscopic Surgery

Zhao, Ran; Yao, Yao; Luo, Yun

doi:10.1115/1.4032813

Cited by 62 publications

(34 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared to previously reported active cooling systems that used either water [13,20,39] or air, [21] our cooling system is among those that achieve the highest cooling rates ( Figure 6D). Moreover, the design has a simpler construction than those systems that employ water for cooling due to no requirement for circulating systems, rendering it more practical for real-time applications.…”

Section: Characterization Of the Vss Thermal Propertiesmentioning

confidence: 58%

Bio‐Inspired Conformable and Helical Soft Fabric Gripper with Variable Stiffness and Touch Sensing

Hoang

Phan

Thai

et al. 2020

Adv Materials Technologies

View full text Add to dashboard Cite

compliance of constituent materials enables soft grippers to safely work with flexible, fragile, and delicate objects. A great number of actuation methods have been investigated, including cable-driven mechanisms, [19] fluid elastomer actuators (FEA), [20,21] dielectric elastomer actuators, [22,23] magnetic actuators, [24-26] and shape memory materials including metal alloys [27,28] and polymers. [29] Among these actuation methods, FEA is one of the oldest and the most widespread technologies employed for soft robotic grippers owing to a number of advantages such as lightweight, high power-to-weight ratio, large stroke and force production, ease of fabrication, robustness, and low-cost materials. [30,31] FEA-based soft grippers have been mostly developed based on claws or human-like structures consisting of multiple inward-bending fingers. This design is suitable for gripping objects spanning a wide range of sizes. However, existing FEA-based grippers are ill-suited for applications that require high conformability or high-load sustainability. The integration of electro-adhesion, [23,32] gecko adhesion, [33,34] or variable stiffness structures (VSSs) can help improve the load capacity. Several studies also address both the issues by designing robotic fingers that can adjust their effective length via the use of segments of VSS. [21] Two main types of VSSs for soft grippers include vacuum-driven jamming of granules [35,36] or layers, [6] and phase-change materials such as thermoplastics, [12,37] shape memory polymers (SMPs), [20,21,38] and low-melting-point alloys (LMPAs). [22,39,40] In another approach, grippers with closed structures have been investigated in an attempt to improve both conformability and load capacity. [23,24,38-40] However, grippers with closed structures are not able to grip objects that are either smaller or larger than the opening orifice of the gripper. Another approach that has also been investigated involves the use of helical winding to enclose objects. This gripping strategy was inspired by natural instances such as elephant trunks, python body constriction, or cephalopod tentacles that use a continuum finger to helically grasp around the objects, thereby increasing the area of contact and stability between the gripper and objects. [41] Continuum, helical grippers that are not constrained by any host have the advantage of being free to wrap around objects and adapt to a wide range of object sizes, shapes, and orientations. There are many instances in nature where continuum, helical manipulators are used to efficiently grasp different objects with various shapes and sizes. Inspired by nature, this paper introduces a continuum, flat, scalable, helical soft-fabric robotic gripper that is thin and lightweight with stiffness tunability and sensory feedback. The gripper is fabricated by a facile method of simple insertion using a computerized technique from apparel engineering and controlled by a miniature hydraulic source to grasp different objects at different scales and weights. It uses a ...

show abstract

Section: Characterization Of the Vss Thermal Propertiesmentioning

confidence: 58%

Bio‐Inspired Conformable and Helical Soft Fabric Gripper with Variable Stiffness and Touch Sensing

Hoang

Phan

Thai

et al. 2020

Adv Materials Technologies

View full text Add to dashboard Cite

show abstract

“…The thin layer keeps the internal channels unimpeded, but still requires a vacuum pump as an additional power source [62]. [75,76], Shape Memory Polymer (SMP) [77,78], Electro-active Polymer (EAP) [79], Thermoplastic Polymer (TP) [80,81], and so forth. Many researchers use these materials through the control of magnetic field, electric field, temperature and other certain conditions to make it in the liquid phase and solid phase mutual conversion, so as to control the stiffness of the CRs and soft material-based devices.…”

Section: Mechanism-based Variable Stiffness Methodsmentioning

confidence: 99%

Recent Advances in Design and Actuation of Continuum Robots for Medical Applications

Zhong

2020

Actuators

View full text Add to dashboard Cite

Traditional rigid robot application in the medical field is limited due to the limited degrees of freedom caused by their material and structure. Inspired by trunk, tentacles, and snakes, continuum robot (CR) could traverse confined space, manipulate objects in complex environment, and conform to curvilinear paths in space. The continuum robot has broad prospect in surgery due to its high dexterity, which can reach circuitous areas of the body and perform precision surgery. Recently, many efforts have been done by researchers to improve the design and actuation methods of continuum robots. Several continuum robots have been applied in clinic surgical interventions and demonstrated superiorities to conventional rigid-link robots. In this paper, we provide an overview of the current development of continuum robots, including the design principles, actuation methods, application prospect, limitations, and challenge. And we also provide perspective for the future development. We hope that with the development of material science, Engineering ethics, and manufacture technology, new methods can be applied to manufacture continuum robots for specific surgical procedures.

show abstract

“…Joule heating of Cerrolow 117 embedded in dielectric elastomer is also used for a variable stiffness gripper [35]. An overtube for endoscopic applications based on LMPA is described in [36], using hot water to activate the change in stiffness. Numerous low melting point polymers are available with various transition temperatures [13,38].…”

Section: Methodsmentioning

confidence: 99%

Flexible Medical Devices: Review of Controllable Stiffness Solutions

2017

View full text Add to dashboard Cite

Abstract:In the medical field and in soft robotics, flexible devices are required for safe human interaction, while rigid structures are required to withstand the force application and accuracy in motion. This paper aims at presenting controllable stiffness mechanisms described in the literature for applications with or without shape-locking performances. A classification of the solutions based on their working principle is proposed. The intrinsic properties of these adaptive structures can be modified to change their mechanical characteristics from a geometrical point of view or equivalent elastic properties (with internal mechanisms or with a change in material properties). These solutions are compared quantitatively, based on selected criteria linked to the medical field as the stiffness range, the activation time and the working conditions. Depending on the application and its requirements, the most suitable solution can be selected following the quantitative comparisons. Several applications of these tunable stiffness structures are proposed and illustrated by examples of the literature.

show abstract

Development of a Variable Stiffness Over Tube Based on Low-Melting-Point-Alloy for Endoscopic Surgery

Cited by 62 publications

References 30 publications

Bio‐Inspired Conformable and Helical Soft Fabric Gripper with Variable Stiffness and Touch Sensing

Bio‐Inspired Conformable and Helical Soft Fabric Gripper with Variable Stiffness and Touch Sensing

Recent Advances in Design and Actuation of Continuum Robots for Medical Applications

Flexible Medical Devices: Review of Controllable Stiffness Solutions

Contact Info

Product

Resources

About