Shape memory alloy-spring damper for seismic control and its application to bridge with laminated rubber bearings

2021 ◽  
pp. 136943322110339
Author(s):  
Sasa Cao ◽  
Jiang Yi
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Large Deformation ◽  
Design Procedure ◽  
Hysteretic Behavior ◽  
Small Displacement ◽  
Seismic Excitations ◽  
Seismic Control ◽  
Sma Spring ◽  
Rubber Bearings

This study introduces a shape memory alloy (SMA)-spring damper which is composed of SMA bars and elastic springs arranged in perpendicular. The damper depicts a curved flag-shape hysteretic behavior that is endowed with self-centering capacities and large deformation capabilities but uses reduced amount of SMA material. A design procedure is proposed to apply the SMA-spring damper to the bridge with laminated rubber bearings which would slide under seismic excitations. Analytical results validate the effectiveness of SMA-spring dampers in seismic control of the bridge: (1) The damper provides trivial stiffness to the bridge at small displacement, and the isolation efficiency of the bridge is maintained; (2) large horizontal force is provided for the structures at large deformation of the bearings, which alleviates the excessive displacement of bearings and prevents span collapse; and (3) the damper helps recenter the bearings and reduce the residual displacement of the bridge.

Design of Shape Memory Alloy Damper for Base Isolated Structure

1997 ◽  
Author(s):  
Krzysztof Wilde ◽  
Paolo Gardoni ◽  
Yozo Fujino ◽  
Stefano Besseghini
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Base Isolation ◽  
Hysteretic Behavior ◽  
Isolation System ◽  
Rubber Bearing ◽  
Laminated Rubber Bearing ◽  
Base Isolation System ◽  
Rubber Bearings ◽  
Smart Base Isolation

Abstract Base isolation provides a very effective passive method of protecting the structure from the hazards of earthquakes. The proposed isolation system combines the laminated rubber bearing with the device made of shape memory alloy (SMA). The smart base isolation uses hysteretic behavior of SMA to increase the structural damping of the structure and utilizes the different responses of the SMA at different levels of strain to control the displacements of the base isolation system at various excitation levels. The performance of the smart base isolation is compared with the performance of isolation by laminated rubber bearings to assess the benefits of additional SMA damper for isolation of three story building.

Passive Seismic Control Using Shape Memory Alloy Springs

2006 ◽  
Author(s):  
Yoshitaka Yamashita ◽  
Arata Masuda ◽  
Akira Sone
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Shaking Table ◽  
Scale Model ◽  
Response Analysis ◽  
Acceleration Response ◽  
Restoring Force ◽  
Seismic Control ◽  
Seismic Force ◽  
Sma Spring

In this paper, seismic response analysis is made both experimentally and numerically for a passive isolation device with pseudoelastic shape memory alloy (SMA) spring as a restoring force component. Thanks to the material nonliniarity and the geometrical nonliniarity, the SMA spring used in the device has well-defined softening, or “force limiting”, property that can suppress the acceleration response of the superstructure by limiting the seismic force transmitted from the ground. To illustrate how the presented device can suppress the acceleration response under the prescribed level, shaking table tests of a reduced-scale model of uniaxial isolator are carried out with seismic inputs appropriately scaled both in time and in amplitude. Then, a Preisach model of the SMA spring is constructed for the purpose of design study, and verified by comparing the simulated seismic responses with the experimental ones.

Shape Memory Alloy Based Actively Tuned Undamped Mass Absorber

2012 ◽  
Vol 2 (1) ◽  
pp. 66-74 ◽  
Author(s):  
M. Senthil Kumar ◽  
V. Raj Kumar ◽  
S. Shyamkirthi
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Cantilever Beam ◽  
Active Vibration Control ◽  
Design Procedure ◽  
Structural Response ◽  
Experimental Setup ◽  
Element Analysis ◽  
Labview Software ◽  
Sma Spring

An actively tuned undamped mass vibration absorber (ATVA) based on shape memory alloy (SMA) actuator is developed for attenuation of vibration in a cantilever beam. The design procedure of the ATVA is presented. The system consists of a cantilever beam mounted with shaker to generate the real-time vibration. The SMA spring with mass is attached at free end. The stiffness of SMA spring is varied dynamically in such a way to attenuate the vibration actively. Both simulation and experimentation are carried out. Simulation is carried out using Finite Element Analysis (FEA) package ANSYS software. The experiment was carried out by interfacing the experimental setup with computer along with LabVIEW software through data acquisition card (DAQ). In experimental setup, an accelerometer is used to measure the vibration which is fed to computer and in turn the SMA spring is actuated to change its stiffness which will control the vibration. The results illustrate that the developed ATVA using SMA is very effective in reducing structural response and having great potential to use as an active vibration control media.

Sub-Structure Pseudo-Dynamic Response Test of a Pseudo-Elastic Bracing System Made of Shape Memory Alloy

2005 ◽  
Vol 297-300 ◽  
pp. 628-634 ◽  
Author(s):  
Kenichi Ohi ◽  
Jae Hyouk Choi
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Original Position ◽  
Small Displacement ◽  
Structural System ◽  
Dynamic Tests ◽  
System A ◽  
Hysteretic Damper ◽  
Bracing System ◽  
Fail Safe

This paper deals with shape memory alloy. As a first step to assess the applicability of this kind of alloy in a structural system, a tension bar made of this kind of alloy that exhibits pseudo-elasticity at room temperature is used herein as a passive bracing system. This paper describes sub-structure pseudo-dynamic tests on pseudo-elastic bracing system with hysteretic damper. A pseudo-elastic bracing system is better to be used with other hysteretic elements such as a hysteretic damper. A damper provides energy dissipation within small displacement levels, and a pseudo-elastic bracing system works in turn as a back-up/fail-safe system when an accidental failure of damper or damper interface occurs, and also it helps to pull back the structure to the original position by uninstalling the damper after earthquake.

Shape memory alloy–actuated prestressed composites with application to morphing automotive fender skirts

2018 ◽  
Vol 30 (3) ◽  
pp. 479-494 ◽  
Author(s):  
Venkata Siva C Chillara ◽  
Leon M Headings ◽  
Ryohei Tsuruta ◽  
Eiji Itakura ◽  
Umesh Gandhi ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Smart Materials ◽  
Design Procedure ◽  
Building Blocks ◽  
Smart Composite ◽  
Thermally Induced ◽  
One Dimensional ◽  
Flat Shape

This work presents smart laminated composites that enable morphing vehicle structures. Morphing panels can be effective for drag reduction, for example, adaptive fender skirts. Mechanical prestress provides tailored curvature in composites without the drawbacks of thermally induced residual stress. When driven by smart materials such as shape memory alloys, mechanically-prestressed composites can serve as building blocks for morphing structures. An analytical energy-based model is presented to calculate the curved shape of a composite as a function of force applied by an embedded actuator. Shape transition is modeled by providing the actuation force as an input to a one-dimensional thermomechanical constitutive model of a shape memory alloy wire. A design procedure, based on the analytical model, is presented for morphing fender skirts comprising radially configured smart composite elements. A half-scale fender skirt for a compact passenger car is designed, fabricated, and tested. The demonstrator has a domed unactuated shape and morphs to a flat shape when actuated using shape memory alloys. Rapid actuation is demonstrated by coupling shape memory alloys with integrated quick-release latches; the latches reduce actuation time by 95%. The demonstrator is 62% lighter than an equivalent dome-shaped steel fender skirt.

scholarly journals Development of Subcarangiform Bionic Robotic Fish Propelled by Shape Memory Alloy Actuators

2021 ◽  
Vol 71 (1) ◽  
pp. 94-101
Author(s):  
M. Muralidharan ◽  
I.A. Palani
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Kinematic Model ◽  
Open Loop ◽  
Robotic Fish ◽  
Water Medium ◽  
Light Weight ◽  
Caudal Fin ◽  
Locomotion Pattern ◽  
Sma Spring

In this paper, a shape memory alloy (SMA) actuated subcarangiform robotic fish has been demonstrated using a spring based propulsion mechanism. The bionic robotic fish developed using SMA spring actuators and light weight 3D printed components can be employed for under water applications. The proposed SMA spring-based design without conventional motor and other rotary actuators was able to achieve two-way shape memory effect and has reproduced the subcarangiform locomotion pattern. The positional kinematic model has been developed and the dynamics of the proposed mechanism were analysed and simulated using Automated Dynamic Analysis of Mechanical Systems (ADAMS). An open loop Arduino-relay based switching control has been adopted to control the periodic actuation of the SMA spring mechanism. The undulation of caudal fin in air and water medium has been analysed. The caudal fin and posterior body of the developed fish prototype have taken part in undulation resembling subcarangiform locomotion pattern and steady swimming was achieved in water with a forward velocity of 24.5 mm/s. The proposed design is scalable, light weight and cost effective which may be suitable for underwater surveillance application.

Design of a 2 DOF Shape Memory Alloy Actuator Using SMA Springs

2021 ◽  
Author(s):  
Hussein F. M. Ali ◽  
Youngshik Kim
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Open Loop ◽  
Degree Of Freedom ◽  
Biologically Inspired ◽  
Loop Control ◽  
Actuator System ◽  
Sma Actuator ◽  
Sma Spring ◽  
Two Degree Of Freedom

Abstract In this paper, we developed two degree of freedom shape memory alloy (SMA) actuator using SMA springs. This module can be applied easily to various applications: device holder, artificial finger, grippes, fish robot, and many other biologically inspired applications, where small size and small wight of the actuator are very critical. This actuator is composed of two sets of SMA springs: one set is for the rotation around the X axis (roll angle) and the other set is for the rotation around the Y axis (pitch angle). Each set contains two elements: one SMA spring and one antagonistic SMA spring. We used an inertia sensor (IMU) and two potentiometers for angles feedback. The SMA actuator system is modeled mathematically and then tested experimentally in open-loop and closed-loop control. We designed and experimentally tuned a proportional integrator derivative (PID) controller to follow the set points and to track the desired trajectories. The main goal of the presented controller is to control roll and pitch angles simultaneously in order to satisfy set points and trajectories within the work space. The experimental results show that the two degree of freedom SMA actuator system follows the desired setpoints with acceptable rise time and overshoot.

Experimental and numerical studies on a novel shape-memory alloy wire–woven trusses capable of undergoing large deformation

2019 ◽  
Vol 30 (15) ◽  
pp. 2283-2298
Author(s):  
Zhixiang Rao ◽  
Xiaojun Yan ◽  
Xiaoyong Zhang ◽  
Bin Zhang ◽  
Jun Jiang ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Large Deformation ◽  
Residual Deformation ◽  
Shape Memory Alloy Wire ◽  
Static Compression ◽  
Recoverable Strain ◽  
Alloy Wire ◽  
Assembly Method ◽  
Finite Element Analysis Simulation

Currently, most wire-woven trusses are fabricated with traditional metals such as steel and aluminum, thus the deformation ability is constrained due to the low yield strain of common metals. Shape-memory alloy is a kind of smart material which can bear large recoverable strain while producing hysteresis. Due to the unique capacity of large deformation and remarkable damping property of the shape-memory alloy, a novel lattice trusses assembled by superelastic shape-memory alloy coil springs was proposed. Furthermore, the treatment processes to prepare the shape-memory alloy coil springs and the assembly method to fabricate the shape-memory alloy wire–woven trusses were also introduced. The quasi-static compression under different maximum deformation and temperatures was performed to investigate the mechanical and thermal responses of the proposed shape-memory alloy wire–woven trusses. Cyclic compression tests were also performed to study the functional fatigue of the shape-memory alloy wire–woven trusses. The proposed wire-woven trusses can undergo up to 80% deformation by compression and recover without evident residual deformation after unloading. Finite element analysis simulation of representative volume element under different deformation was presented. Analytical modeling of the stiffness of shape-memory alloy wire–woven trusses was also carried out. Both the numerical and analytical methods can predict the stiffness within a small deviation.

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