Design of a two degree of freedom shape memory alloy actuator for mirror positioning

2006 ◽  
Author(s):  
Eric A. Williams ◽  
Mohammad H. Elahinia
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Degree Of Freedom ◽  
Shape Memory Alloy Actuator ◽  
Two Degree Of Freedom

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.

Effect of constitutive model parameters on the aeroelastic behavior of an airfoil with shape memory alloy springs

2016 ◽  
Vol 24 (6) ◽  
pp. 1065-1085 ◽  
Author(s):  
Vagner Candido de Sousa ◽  
Carlos De Marqui Junior ◽  
Mohammad H Elahinia
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Pure Shear ◽  
Degree Of Freedom ◽  
Model Parameters ◽  
Cross Sectional ◽  
Helical Springs ◽  
Flutter Boundary ◽  
Tension Compression Asymmetry ◽  
Two Degree Of Freedom

The effects of the pseudoelastic hysteresis of shape memory alloy springs on the aeroelastic behavior of a typical airfoil section are numerically investigated for six different sets of alloy constitutive properties. A two-degree-of-freedom (namely, plunge and pitch) typical section is modeled. Shape memory alloy helical springs are considered in the pitch degree-of-freedom based on classical phenomenological models modified by the pure shear assumption. Tension–compression asymmetry and nonhomogeneous distributions of shear strain, shear stress and martensitic fraction in the cross-sectional area of the coiled shape memory alloy wire are considered. A linear model is used to determine the unsteady aerodynamic loads. Attractive alloy characteristics, which can enhance the aeroelastic behavior of the typical section at the flutter boundary and at the post-flutter regime, are identified and discussed in detail.

scholarly journals Bifurcation and Chaos in Integer and Fractional Order Two-Degree-of-Freedom Shape Memory Alloy Oscillators

Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Karthikeyan Rajagopal ◽  
Anitha Karthikeyan ◽  
Prakash Duraisamy ◽  
Riessom Weldegiorgis
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Fractional Order ◽  
Dynamical Behavior ◽  
Degree Of Freedom ◽  
Order Model ◽  
Bifurcation And Chaos ◽  
Fractional Order Model ◽  
Two Degree Of Freedom ◽  
Fractional Orders

A two-degree-of-freedom shape memory oscillator derived using polynomial constitutive model is investigated. Periodic, quasiperiodic, chaotic, and hyperchaotic oscillations are shown by the shape memory alloy based oscillator for selected values of the operating temperatures and excitation parameters. Bifurcation plots are derived to investigate the system behavior with change in parameters. A fractional order model of the shape memory oscillator is presented and dynamical behavior of the system with fractional orders and parameters are investigated.

scholarly journals Electromagnetic Control by Actuating Kirigami-Inspired Shape Memory Alloy: Thermally Reconfigurable Antenna application

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3026
Author(s):  
Minjae Lee ◽  
Sukwon Lee ◽  
Sungjoon Lim
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Fast Response ◽  
Electromagnetic Response ◽  
Reconfigurable Antenna ◽  
Thermal Stimulus ◽  
Shape Memory Alloy Actuator ◽  
Antenna Performance ◽  
Mechanical Transformation ◽  
Electromagnetic Control

Electromagnetic responses are generally controlled electrically or optically. However, although electrical and optical control allows fast response, they suffer from switching or tuning range limitations. This paper controls electromagnetic response by mechanical transformation. We introduce a novel kirigami-inspired structure for mechanical transformation with less strength, integrating a shape memory alloy actuator into the kirigami-inspired for mechanical transformation and hence electromagnetic control. The proposed approach was implemented for a reconfigurable antenna designed based on structural and electromagnetic analyses. The mechanical transformation was analyzed with thermal stimulus to predict the antenna geometry and electromagnetic analysis with different geometries predicted antenna performance. We numerically and experimentally verified that resonance response was thermally controlled using the kirigami-inspired antenna integrated with a shape memory alloy actuator.

Sign in / Sign up

Export Citation Format

Share Document