A review of shape memory alloy research, applications and opportunities

https://download.e-bookshelf.de/download/0000/0136/58/L-G-0000013658-0002346818.pdf

Burrs—Analysis, control and removal

Introduction to surface topography.- The areal field parameters.- The areal feature parameters.- Areal filtering methods.- Areal form removal.- Areal fractal methods.- Choosing the appropriate parameter.- Characterization of individual areal features.- Multi-scale signature of surface topography.- Correlation of areal surface texture parameters to solar cell efficiency.- Characterisation of cylinder liner honing textures for production control.- Characterization of the mechanical bond strength for copper on glass plating applications.- Inspection of laser structured cams and conrods.- Road surfaces.

Characterisation of Areal Surface Texture

Shape memory alloys (SMAs) are a unique class of metallic materials with the ability to recover their original shape at certain characteristic temperatures (shape memory effect), even under high applied loads and large inelastic deformations, or to undergo large strains without plastic deformation or failure (super-elasticity). In this review, we describe the main features of SMAs, their constitutive models and their properties. We also review the fatigue behavior of SMAs and some methods adopted to remove or reduce its undesirable effects. SMAs have been used in a wide variety of applications in different fields. In this review, we focus on the use of shape memory alloys in the context of morphing aircraft, with particular emphasis on variable twist and camber, and also on actuation bandwidth and reduction of power consumption. These applications prove particularly challenging because novel configurations are adopted to maximize integration and effectiveness of SMAs, which play the role of an actuator (using the shape memory effect), often combined with structural, load-carrying capabilities. Iterative and multi-disciplinary modeling is therefore necessary due to the fluid–structure interaction combined with the nonlinear behavior of SMAs.

/pdf/a-review-on-shape-memory-alloys-with-applications-to-37zf5uq39g.pdf

A review on shape memory alloys with applications to morphing aircraft

Corrosion behaviour of commercially pure titanium shot blasted with different materials and sizes of shot particles for dental implant applications

Purpose – The purpose of this paper is to review the current application areas of shape memory alloy (SMA) actuators in intelligent robotic systems and devices.Design/methodology/approach – This paper analyses how actuation and sensing functions of the SMA actuator have been exploited and incorporated in micro and macro robotic devices, developed for medical and non‐medical applications. The speed of response of SMA actuator mostly depends upon its shape and size, addition and removal of heat and the bias force applied. All these factors have impact on the overall size of the robotic device and the degree of freedom (dof) obtained and hence, a comprehensive survey is made highlighting these aspects. Also described are the mechatronic aspects like the software and hardware used in an industrial environment for the control of such nonlinear actuator and the type of sensory feedback devices incorporated for obtaining better control, positioning accuracy and fast response.Findings – SMA actuators find wide ap...

Critical review of current trends in shape memory alloy actuators for intelligent robots

Flapper–nozzle type Electro Hydraulic Servo Valve (EHSV) operated by conventional torque motor actuators has been used in wide range of industrial applications. As their bandwidths are limited, they are not suitable for high-speed applications. The work presented in this paper deals with the mechatronic approach for the design of a magnetostrictive actuator with flexure amplifier and a magnetically biased magnetostrictive actuator for application in high frequency flapper–nozzle servo valve. A magnetostrictive actuator has been designed, built and integrated into an existing flapper–nozzle servo valve by replacing the torque motor. Incorporating the dynamics of the magnetostrictive actuator, the dynamics of the valve was simulated. Necessary parameters for the actuator have been arrived by finite element model. No load flow characteristics are analyzed and compared with experimental values. Step response has been compared with conventional valve. The results show that the valve has satisfactory static and dynamic characteristics for applications in high-speed actuation systems.

Design, analysis and simulation of magnetostrictive actuator and its application to high dynamic servo valve

Surface topography and, in particular, roughness and form, plays an important role in determining the functional performance of engineering parts. The measurement and understanding of surface topography is rapidly attracting the attention of the physicist, the biologist and the chemist as well as the engineer. Optics in general played an important role in measurement and, with the advent of opto-mechatronics, it is once again at the forefront of measurement. In this paper, the principles and performance of a confocal microscope, together with the measurement system, are described. Suitable fixtures are developed and integrated with the computer system for generating three-dimensional surface and form data. Software for data acquisition, analysis of various parameters including new parameters and visualization of surface geometrical features has been developed. Both the intensity and the auto-focus methods are used to measure two-dimensional surface roughness by use of the system and results are presented. The measurement and characterization of three-dimensional surface topography and form error will be presented in part II of this paper.

https://iopscience.iop.org/article/10.1088/0957-0233/11/3/320/pdf

Characterization of surface topography by confocal microscopy : I. Principles and the measurement system

Numerical generation of anisotropic 3D non-Gaussian engineering surfaces with specified 3D surface roughness parameters

This paper reviews recent developments in nonlinear control technologies for shape memory alloy (SMA) actuators in robotics and their related applications. SMA possesses large hysteresis, low bandwidth, slow response, and non-linear behavior, which make them difficult to control. The fast response of the SMA actuator mostly depends upon, (1) type of controller, (2) rate of addition and removal of heat, and (3) shape or form of the actuator. Though linear controllers are more desirable than nonlinear ones, the review of literature shows that the results obtained using nonlinear controllers were far better than the former one. Therefore, more emphasis is made on the nonlinear control technologies taking into account the intelligent controllers. Various forms of SMA actuator along with different heating and cooling methods are presented in this review, followed by the nonlinear control methods and the control problems encountered by the researchers.

M. Singaperumal

Papers

Critical review of current trends in shape memory alloy actuators for intelligent robots

Design, analysis and simulation of magnetostrictive actuator and its application to high dynamic servo valve

Characterization of surface topography by confocal microscopy : I. Principles and the measurement system

Numerical generation of anisotropic 3D non-Gaussian engineering surfaces with specified 3D surface roughness parameters

Recent advances in nonlinear control technologies for shape memory alloy actuators