scholarly journals Modelling of SMA Vibration Systems in an AVA Example

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5905
Author(s):  
Waldemar Rączka ◽  
Jarosław Konieczny ◽  
Marek Sibielak
Keyword(s):  
Shape Memory ◽  
Vibration Suppression ◽  
Viscoelastic Model ◽  
Analysis Method ◽  
Dynamic Vibration Absorber ◽  
Object A ◽  
Scientific Investigations ◽  
Frequency Excitation ◽  
Sma Spring ◽  
Vibrating Systems

Vibration suppression, as well as its generation, is a common subject of scientific investigations. More and more often, but still rarely, shape memory alloys (SMAs) are used in vibrating systems, despite the fact that SMA springs have many advantages. This is due to the difficulty of the mathematical description and the considerable effortfulness of analysing and synthesising vibrating systems. The article shows the analysis of vibrating systems in which spring elements made of SMAs are used. The modelling and analysis method of vibrating systems is shown in the example of a vibrating system with a dynamic vibration absorber (DVA), which uses springs made of a shape memory alloy. The formulated mathematical model of a 2-DOF system with a controlled spring, mounted in DVA suspension, uses the viscoelastic model of the SMA spring. For the object, a control system was synthesised. Finally, model tests with and without a controller were carried out. The characteristics of the vibrations’ transmissibility functions for both systems were determined. It was shown that the developed DVA can tune to frequency excitation changes of up to ±10%.

scholarly journals Longitudinal vibration compensation model of stepped-pipe strings in deep-sea mining

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0241650
Author(s):  
QingHui Song ◽  
HaiYan Jiang ◽  
QingJun Song ◽  
Linjing Xiao ◽  
Qiang Liu
Keyword(s):  
Dynamic Model ◽  
Deep Sea ◽  
Vibration Suppression ◽  
Longitudinal Vibration ◽  
Damping Ratio ◽  
Sea Breeze ◽  
Analysis Method ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Spring Coefficient

In this paper, the dynamic model of the rigid space stepped-pipe strings system is derived with Lagrangian method to represent the system dynamic behaviors which enriches the analysis method of longitudinal vibration of stepped-pipe strings. The stepped-pipe strings is constructed of pipes with different diameters and lengths, the physical properties of which mainly depends on the axial force and the depth of deep-sea mining. Based on lumped element method, the heave compensation system with dynamic vibration absorber is designed for longitudinal vibration suppression of the stepped-pipe strings. The analytical solution is obtained by modal analysis method when the mining ship is subjected to sea breeze excitation. The proposed method is easily implementable for rigid space stepped-pipe strings system with complex multi-degree-of-free deep-sea mining dynamic model. Furthermore, the optimal combination of mass ratio, spring coefficient and damping ratio is shown to have a better vibration suppression performance. Finally, numerical simulations on the stepped-pipe strings system with or without dynamic vibration absorbers are provided to demonstrate the effectiveness of the proposed method.

Application of a Shape Memory Absorber in Vibration Suppression

2016 ◽  
Vol 849 ◽  
pp. 27-35 ◽  
Author(s):  
Vinícius Piccirillo ◽  
José M. Balthazar ◽  
Angelo Marcelo Tusset ◽  
Davide Bernardini ◽  
Giuseppe Rega
Keyword(s):  
Shape Memory ◽  
Vibration Suppression ◽  
High Amplitude ◽  
Memory Device ◽  
Internal Variable ◽  
Hysteretic Behavior ◽  
Thermomechanical Model ◽  
Dynamic Vibration Absorber ◽  
Restoring Force ◽  
Dynamic Vibration

The dynamic response of structures subjected to high-amplitude vibration is often dangerous and undesirable. Dynamic vibration absorbers (DVA) have received special attention in recent years due to vibration attenuation offered by them. Thus, the present study analyzes the nonlinear dynamics of a system with a dynamic vibration absorber (DVA) using a shape memory material (SMM) whose characteristics are highly dependent upon temperature. The restoring force of the oscillator is provided by a shape-memory device (SMD) described by a thermomechanical model capable to describe the hysteretic behavior via the evolution of a suitable internal variable. Numerical simulations show the effectiveness of using the SMM in reducing oscillations of a harmonic oscillator.

Design Equations for Binary Shape Memory Actuators Under Arbitrary External Forces

2011 ◽  
Author(s):  
Andrea Spaggiari ◽  
Igor Spinella ◽  
Eugenio Dragoni
Keyword(s):  
Shape Memory ◽  
Dissipative Force ◽  
Arbitrary System ◽  
Constant Force ◽  
Shape Memory Alloy Actuator ◽  
Shape Memory Actuators ◽  
Step Procedure ◽  
Sma Actuator ◽  
Sma Spring ◽  
External Forces

The paper presents the design equations for an on-off shape memory alloy actuator under an arbitrary system of external constant forces. A binary SMA actuator is considered where a cursor is moved against both conservative and dissipative force which may be different during the push or pull phase. Three cases are analyzed and differentiated in the way the bias force is applied to the primary SMA spring, using a constant force, a traditional spring, or a second SMA spring. Closed-form dimensionless design equations are developed, which form the basis of a step-by-step procedure for an optimal design of the whole actuator.

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.

Tunable and Transferrable Bar Feeder Damping Design for Advanced Manufacturing

2013 ◽  
Author(s):  
Harry A. Pierson ◽  
Kumer V. Singh
Keyword(s):  
Vibration Suppression ◽  
Control Strategies ◽  
Active Vibration Control ◽  
Viscoelastic Model ◽  
Advanced Manufacturing ◽  
Euler Beam ◽  
Batch Sizes ◽  
Active Vibration ◽  
Cnc Turning Centers ◽  
High Degree

The economical production of high-value, low-volume, machined components is an important subtopic of advanced manufacturing. Bar feeders, a well-established technology for adding a high degree of automation to CNC turning centers by feeding 12′ lengths of stock through the machine spindle, have limitations in this realm. They rely on supporting the entire length of the stock in a continuous fluid bearing in order to suppress potential vibrations. Although this results in excellent vibration suppression, long tooling changeovers make them impractical for small batch sizes. Additionally, the expense of the tooling can render them cost-prohibitive. Thus a bar feeder technology is desired that provides comparable vibration suppression for a wide variety of stock sizes without the need for size-specific tooling changes. In this, a movable point support having tunable viscoelastic properties is studied for controlling the vibration of varying lengths of bar stock in a given speed range. The transverse vibration of mounted bar stock is modeled as a Bernoulli-Euler beam. The effects of the support position, viscoelastic model, and their associated parameters on the resonant frequencies, damping ratios, and vibration response of the bar stock are studied. Such a study will be instrumental in developing passive/active vibration control strategies for future bar feeders.

scholarly journals Application of Adaptive Tuned Magneto-Rheological Elastomer for Vibration Reduction of a Plate by a Variable-Unbalance Excitation

2020 ◽  
Vol 10 (11) ◽  
pp. 3934 ◽  
Author(s):  
Un-Chang Jeong
Keyword(s):  
Vibration Reduction ◽  
Excitation Frequency ◽  
Target Object ◽  
Vibration Absorber ◽  
Magnetorheological Elastomer ◽  
Dynamic Vibration Absorber ◽  
Mass Part ◽  
Dynamic Vibration ◽  
Frequency Excitation ◽  
Magneto Rheological

The present study on vibration reduction in systems wherein the excitation frequency is variable designed and fabricated a magnetorheological elastomer (MRE)-based tunable dynamic vibration absorber and evaluated its performance in an experimental manner. The design of an MRE-based adaptive tuned dynamic vibration absorber (ATDVA) involves designing two parts: stiffness and mass. Before designing the MRE-based ATDVA, this study determined the resonance frequency of a target object for vibration reduction. For the design of the ATDVA’s stiffness part, the thickness of specimens was determined by measuring the rate of variation of the MRE’s shear modulus with respect to the MRE’s thickness. The design of the mass part was optimized using sensitivity analysis and genetic algorithms after the derivation of formulas for its magnetic field and mass. Further, upon the application of an electric current to the MRE, its stiffness was measured so that the stiffness of the designed MRE-based ATDVA could be tuned accordingly. Finally, the vibration-reducing performance of the MRE-based ATDVA was evaluated to determine the applicability of the vibration absorber under the condition of variable-frequency excitation.

Adaptive-passive structural vibration attenuation using distributed absorbers

2002 ◽  
Vol 216 (3) ◽  
pp. 223-235 ◽  
Author(s):  
N Jalili ◽  
E Esmailzadeh
Keyword(s):  
Vibration Suppression ◽  
Sufficient Conditions ◽  
Structural Vibration ◽  
Dynamic Vibration Absorber ◽  
Vibration Attenuation ◽  
Adaptive Capability ◽  
On Line ◽  
Lumped Masses ◽  
Necessary And Sufficient ◽  
Tuning Strategy

A distributed dynamic vibration absorber with adaptive capability is presented to improve vibration suppression characteristics of harmonically excited structures. A double-ended cantilever beam carrying intermediate lumped masses forms the absorber subsection. The adaptive capability is achieved through concurrent adjustment of the positions of the moving masses, along the beam, to comply with the desired optimal performance. The necessary and sufficient conditions for the existence of periodic oscillatory behaviour, along with some physical bounds placed on the absorber parameters, form a constrained optimization problem for the optimum tuning strategy. Through numerical simulations it is shown that adaptive tuning is achieved by the variation of tuning mass locations such that the first-mode natural frequency is modulated on-line. The optimally tuned absorber provides considerable vibration suppression improvement over the passive and detuned absorbers.

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