Advanced Controlling of the Prototype of SMA Linear Actuator

2011 ◽  
Vol 177 ◽  
pp. 93-101 ◽  
Author(s):  
Ireneusz Dominik
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Knowledge Base ◽  
Real Time ◽  
Fuzzy Controller ◽  
Learning Algorithm ◽  
Linear Actuator ◽  
Sma Actuator ◽  
Auto Tuning ◽  
Continuous Work

During research on SMA wires the prototype of linear position actuator was built. The shape memory alloy (SMA) wires used in construction of the actuator are nonlinear and time variant. Thus, it was decided to use a fuzzy controller to control the actuator. However, because of the nature of SMA wires which work by changes of their temperature, after a few minutes of continuous work the actuator did not work accurately. In other words, the existing singleton values in a knowledge base were inappropriate. That is why each time after longer continuous work of the actuator it was needed to manually find and change the mentioned values. It took a lot of time and effort so eventually it was decided to create a real time auto-tuning algorithm which could identify crucial parameters of the actuator each time when it was needed. Together with initial values learning algorithm the advanced controlling of SMA actuator was created.

Modeling and Tracking Control System of Shape Memory Alloy Actuator

2007 ◽  
Author(s):  
B. Y. Ren ◽  
B. Q. Chen
Keyword(s):  
Control System ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Tracking Control ◽  
Fuzzy Controller ◽  
Smart Structures ◽  
Constitutive Law ◽  
Hysteresis Model ◽  
Sma Actuators ◽  
Sma Actuator

The different Shape Memory Alloy (SMA) actuators have been widely used in the fields of smart structures. However, the accurate prediction of thermomechanical behavior of SMA actuators is very difficult due to the nonlinearity of inherence hysteresis of SMA. Therefore, the tracking control accuracy of SMA actuator is very important for the practical application of the SMA actuator. A dynamic hysteresis model of bias-type SMA actuator based on constitutive law developed by Brinson et al. and hysteresis model developed by Ikuta et al. is presented. The control systems composed of the Proportional Integral Derivative (PID) controller as well as a fuzzy controller or a fuzzy-PID composite controller for compensating the hysteresis is proposed. The effort of tracking control system is analyzed according to the simulation on the displacement of SMA actuator with the three kinds of controllers. The result can provide a reference for the application of SMA actuator in the fields of smart structures.

A Novel Design of a Large-Stroke Shape Memory Alloy Linear Actuator

2019 ◽  
Author(s):  
Fei Yang ◽  
Jian Wang ◽  
Miaoling Han ◽  
Yifan Lu ◽  
Honghao Yue ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Linear Actuator ◽  
Confined Space ◽  
Output Displacement ◽  
Tandem Structure ◽  
In Series ◽  
Sma Actuator ◽  
Application Fields ◽  
Actuation Systems

Abstract The traditional actuation systems such as combustion engines, electro motors, hydraulic and pneumatic machines, have several drawbacks: large volume and weight, huge energy consumption and high cost. To overcome these problems, this paper presents a novel large-stroke linear actuator actuated by shape memory alloy (SMA) wires. Multiple SMA wires are distributed in the space three-dimensionally and connected in series to achieve a larger stroke of the actuator. The tandem structure makes the SMA actuator easy to integrate into a narrow available space with dimension constraints. A theoretical model for bias element selection is developed through analysis of the driving paths. A prototype of the proposed SMA actuator is fabricated and corresponding experiments are conducted to verify the functions and performances. The critical working performances of the SMA actuator such as the output displacement, heating electric current, actuation time and reset time are obtained and investigated. The results prove that the proposed SMA actuator can output an ideal driving stroke and enough actuation force in confined space. This research provides design ideas for the large-stroke SMA actuator in more application fields.

Set Point Force Control of Shape Memory Alloy Actuator Using Fuzzy Controller

2013 ◽  
Vol 433-435 ◽  
pp. 166-173
Author(s):  
Fei Gao ◽  
Hua Deng
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Control Strategy ◽  
Force Control ◽  
Fuzzy Controller ◽  
Point Force ◽  
Control Voltage ◽  
Set Point ◽  
Output Force ◽  
Sma Actuator

Shape memory alloy (SMA) has a property that when the temperature of SMA is stabilized, the fraction of Martensite phase keeps the same, and output force of SMA actuator also keeps constant. Based on that, a control strategy for set point force control of SMA actuators is proposed that during the process of driving, to stabilize output forces of SMA actuator, some voltages called balance voltages which can stabilize the temperature of SMA at the point will be input to SMA actuator. Besides, in order to shorten force rising times, before output force reaches the desired force, the max control voltage will be input to SMA actuator. Those balance voltages are related to output forces, therefore, its impossible to get all balance voltages. In this thesis, some balance voltages at different output forces are acquired by experiments. Based on this data, a series of fuzzy rules are used to fit the curve of all balance voltages. Since the balance voltages line is not accurate, balance voltages are needed to be slightly adjusted near the fitting curve according to force errors. Based on the control strategy, a fuzzy controller, with two input variables-desired force and force error and one output-control voltage, is designed. Finally, for testing the performance of the proposed controller, an experimental prototype is implemented. Experiment results show that the proposed controller is successfully applied to SMA actuator, and have a better control performance than conventional PI controller.

scholarly journals Bio-inspired Miniature Suction Cups Actuated by Shape Memory Alloy

10.5772/7228 ◽  
2009 ◽  
Vol 6 (3) ◽  
pp. 29 ◽  
Author(s):  
Hu Bing-Shan ◽  
Wang Li-Wen ◽  
Fu Zhuang ◽  
Zhao Yan-zheng
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Analytical Model ◽  
Basic Structure ◽  
Thin Elastic Plate ◽  
Climbing Robots ◽  
Suction Cup ◽  
Sma Actuator ◽  
Suction Cups ◽  
Pressure Suction

Wall climbing robots using negative pressure suction always employ air pumps which have great noise and large volume. Two prototypes of bio-inspired miniature suction cup actuated by shape memory alloy (SMA) are designed based on studying characteristics of biologic suction apparatuses, and the suction cups in this paper can be used as adhesion mechanisms for miniature wall climbing robots without air pumps. The first prototype with a two-way shape memory effect (TWSME) extension TiNi spring imitates the piston structure of the stalked sucker; the second one actuated by a one way SMA actuator with a bias has a basic structure of stiff margin, guiding element, leader and elastic element. Analytical model of the second prototype is founded considering the constitutive model of the SMA actuator, the deflection of the thin elastic plate under compound load and the thermo-dynamic model of the sealed air cavity. Experiments are done to test their suction characteristics, and the analytical model of the second prototype is simulated on Matlab/simulink platform and validated by experiments.

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.

Discrete Preisach Model of a Shape Memory Alloy Actuator

2016 ◽  
Vol 248 ◽  
pp. 227-234
Author(s):  
Waldemar Rączka ◽  
Jarosław Konieczny ◽  
Marek Sibielak ◽  
Janusz Kowal
Keyword(s):  
Mathematical Model ◽  
Shape Memory Alloy ◽  
Parameter Identification ◽  
Shape Memory ◽  
Preisach Model ◽  
Discrete Form ◽  
Nonlinear Characteristics ◽  
Shape Memory Alloy Actuator ◽  
Sma Actuator ◽  
Identification Model

Shape Memory Alloy is a material used to designing actuators. These actuators have many advantages. They are light, strong and silent. They are building in laboratory and tested because beside advantages they have disadvantages too. SMA actuators have nonlinear characteristics with hysteresis loop.In the first part of the paper Shape Memory Alloys are shortly described. Next mathematical model was formulated. In the paper the Preisach model was developed. Discrete form of the model was considered and implemented. After parameter identification model was implemented in LabView. Tests of the model were conducted and results were worked. Obtained characteristics of the SMA actuator are shown in the paper. At the end of the paper the conclusions were formulated.

Characteristics of Experimental MSMA-Based Pneumatic Valves

2013 ◽  
Author(s):  
Stanislaw Flaga ◽  
Andrzej Sioma
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Initial Study ◽  
General Construction ◽  
Linear Actuator ◽  
Magnetic Shape Memory ◽  
Electromechanical Transducer ◽  
One Stage ◽  
Magnetic Shape Memory Alloy ◽  
Pneumatic Valves

In the course of work on a linear actuator based on a magnetic shape memory alloy (MSMA), a research workstation was constructed enabling the examination of pneumatic valves featuring an electromechanical transducer created with MSMA technology. In this article, the general construction of the research workstation is presented, together with an initial study of a demonstrator of a pneumatic, one-stage, one-way throttle valve. In the presented demonstrator, a simple replacement of a electromechanical transducer into a transducer created with MSMA technology was performed. In addition, the study also describes the problems appearing in such structures along with potential troubleshooting methods.

Sign in / Sign up

Export Citation Format

Share Document