3D PRINTED HEXAPOD ROBOT ACTUATED BY SHAPE MEMORY ALLOY SPRINGS: DESIGN AND PERFORMANCE ANALYSIS

Shape Memory Alloy (SMA)-actuators are efficient, simple, and robust alternatives to conventional actuators when a small volume and/or large force and stroke are required. The analysis of their failure response is critical for their design in order to achieve optimum functionality and performance. Here, (i) the existing knowledge base on the fatigue and overload fracture response of SMAs under actuation loading is reviewed regarding the failure micromechanisms, empirical relations for actuation fatigue life prediction, experimental measurements of fracture toughness and fatigue crack growth rates, and numerical investigations of toughness properties and (ii) future developments required to expand the acquired knowledge, enhance the current understanding, and ultimately enable commercial applications of SMA-actuators are discussed.

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Low Velocity Impact Performance Analysis of Fiber Composite Structure Embedded with Shape Memory Alloy

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES AEROSPACE TECHNOLOGY JAPAN ◽

10.2322/tastj.12.pc_35 ◽

2014 ◽

Vol 12 (ists29) ◽

pp. Pc_35-Pc_41

Author(s):

Ying-Chih LIN ◽

Yu-Liang CHEN ◽

Hung-Wen CHEN

Keyword(s):

Performance Analysis ◽

Shape Memory Alloy ◽

Shape Memory ◽

Composite Structure ◽

Fiber Composite ◽

Low Velocity Impact ◽

Low Velocity ◽

Velocity Impact ◽

Impact Performance

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A shape memory alloy–actuated soft crawling robot based on adaptive differential friction and enhanced antagonistic configuration

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x20942319 ◽

2020 ◽

Vol 31 (16) ◽

pp. 1920-1934 ◽

Cited By ~ 2

Author(s):

Chen Liang ◽

Yongquan Wang ◽

Tao Yao ◽

Botao Zhu

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Stride Length ◽

Parametric Design ◽

Thermoplastic Polyurethane ◽

Interaction Mechanism ◽

Experimental Tests ◽

The Body ◽

3D Printed ◽

Miniature Robot

This article presents a soft crawling robot prototype with a simple architecture inspired by inchworms. The robot functionally integrates the torso (body) and feet in a monolithic curved structure that only needs a single shape memory alloy coil and differential friction to actuate it. A novel foot configuration is proposed, which makes the two feet, with an anti-symmetrical friction layout, can be alternately anchored, to match the contraction–recovery sequence of the body adaptively. Based on the antagonistic configuration between the shape memory alloy actuator and the elastic body, a vertically auxiliary spring was adopted to enhance the interaction mechanism. Force and kinematic analysis was undertaken, focusing on the parametric design of the special foot configuration. A miniature robot prototype was then 3D-printed (54 mm in length and 9.77 g in weight), using tailored thermoplastic polyurethane elastomer as the body material. A series of experimental tests and evaluations were carried out to assess its performance under different conditions. The results demonstrated that under appropriate actuation conditions, the compact robot prototype could accomplish a relative speed of 0.024 BL/s (with a stride length equivalent to 27% of its body length) and bear a load over five times to its own weight.

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Design and Performance Evaluation of an Ultradeepwater Subsea Blowout Preventer Control System Using Shape Memory Alloy Actuators

10.2118/101080-ms ◽

2006 ◽

Cited By ~ 2

Author(s):

Ning Ma ◽

ziping hu ◽

Robello Samuel ◽

Christine A. Ehlig-Economides ◽

Gangbing Song

Keyword(s):

Performance Evaluation ◽

Control System ◽

Shape Memory Alloy ◽

Shape Memory ◽

Blowout Preventer ◽

And Performance

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A Soft Five-Fingered Hand Actuated by Shape Memory Alloy Wires: Design, Manufacturing, and Evaluation

Frontiers in Robotics and AI ◽

10.3389/frobt.2020.608841 ◽

2020 ◽

Vol 7 ◽

Author(s):

Filomena Simone ◽

Gianluca Rizzello ◽

Stefan Seelecke ◽

Paul Motzki

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Force Measurement ◽

Optimal Placement ◽

Flexible Structure ◽

Flexible Joints ◽

3D Printed

This work presents a novel five-fingered soft hand prototype actuated by Shape Memory Alloy (SMA) wires. The use of thin (100 μm diameter) SMA wire actuators, in conjunction with an entirely 3D printed hand skeleton, guarantees an overall lightweight and flexible structure capable of silent motion. To enable high forces with sufficiently high actuation speed at each fingertip, bundles of welded actuated SMA wires are used. In order to increase the compliance of each finger, flexible joints from superelastic SMA wires are inserted between each phalanx. The resulting system is a versatile hand prototype having intrinsically elastic fingers, which is capable to grasp several types of objects with a considerable force. The paper starts with the description of the finger hand design, along with practical considerations for the optimal placement of the superelastic SMA in the soft joint. The maximum achievable displacement of each finger phalanx is measured together with the phalanxes dynamic responsiveness at different power stimuli. Several force measurement are also realized at each finger phalanx. The versatility of the prototype is finally demonstrated by presenting several possible hand configurations while handling objects with different sizes and shapes.

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