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1 – 10 of over 4000
Article
Publication date: 5 May 2015

Fabien Hospital, Marc Budinger, Aurélien Reysset and Jean-Charles Maré

This paper aims to propose preliminary design models of actuator housing that enable various geometries to be compared without requiring detailed knowledge of the actuator

Abstract

Purpose

This paper aims to propose preliminary design models of actuator housing that enable various geometries to be compared without requiring detailed knowledge of the actuator components. Aerospace actuation systems are currently tending to become more electrical and fluid free. Methodologies and models already exist for designing the mechanical and electrical components, but the actuator housing design is still sketchy.

Design/methodology/approach

The approach is dedicated to linear actuators, the most common in aerospace. With special attention paid to mechanical resistance to the vibratory environment, simplified geometries are proposed to facilitate the generation of an equivalent formal development. The vibratory environment imposes the sizing of the actuator housing. Depending on the expected level of details and to vibration boundary conditions, three levels of modeling have been realized.

Findings

This paper shows that the vibrations induced by aircraft environment are not design drivers for conventional hydraulic actuators but can be an issue for new electromechanical actuators. The weight of the latter can be optimized through a judicious choice of the diameter of the housing.

Practical implications

This approach is applied to a comparison of six standard designs of linear actuator geometries after validation of the consistency of the different models. Early conclusions can be drawn and may lead to design perspectives for the definition of actuator architecture and the optimization of the design.

Originality/value

This paper has demonstrated the importance of the vibratory environment in the design of linear actuator housing, especially for electro-mechanical actuators with important strokes. Developed analytical models can be used for the overall design and optimization of these new aerospace actuators.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 25 November 2013

Alireza Fathi and Ahmad Mozaffari

The purpose of the current investigation is to design a robust and reliable computational framework to effectively identify the nonlinear behavior of shape memory alloy (SMA…

Abstract

Purpose

The purpose of the current investigation is to design a robust and reliable computational framework to effectively identify the nonlinear behavior of shape memory alloy (SMA) actuators, as one of the most applicable types of actuators in engineering and industry. The motivation of proposing such an intelligent paradigm emanates in the pursuit of fulfilling the necessity of devising a simple yet effective identification system capable of modeling the hysteric dynamical respond of SMA actuators.

Design/methodology/approach

To address the requirements of designing a pragmatic identification system, the authors integrate a set of fast yet reliable intelligent methodologies and provide a predictive tool capable of realizing the nonlinear hysteric behavior of SMA actuators in a computationally efficient fashion. First, the authors utilize the governing equations to design a gray box Hammerstein-Wiener identifier model. At the next step, they adopt a computationally efficient metaheuristic algorithm to elicit the optimum operating parameters of the gray box identifier.

Findings

Applying the proposed hybrid identifier framework allows the authors to find out its advantages in modeling the behavior of SMA actuator. Through different experiments, the authors conclude that the proposed identifier can be used for identification of highly nonlinear dynamic behavior of SMA actuators. Furthermore, by extending the conclusions and expounding the obtained results, one can easily infer that such a hybrid method may be conveniently applied to model other engineering phenomena that possess dynamic nonlinear reactions. Based on the exerted experiments and implementing the method, the authors come to the conclusion that integrating the power of metaheuristic exploration/exploitation with gray box identifier results a predictive paradigm that much more computationally efficient as compared with black box identifiers such as neural networks. Additionally, the derived gray box method has a higher degree of preference over the black box identifiers, as it allows a manipulated expert to extract the knowledge of the system at hand.

Originality/value

The originality of the research paper is twofold. From the practical (engineering) point of view, the authors built a prototype biased-spring SMA actuator and carried out several experiments to ascertain and validate the parameters of the model. From the computational point of view, the authors seek for designing a novel identifier that overcomes the main flaws associated with the performance of black-box identifiers that are the lack of a mean for extracting the governing knowledge of the system at hand, and high computational expense pertinent to the structure of black-box identifiers.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 6 no. 4
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 27 May 2022

Venkatesan V., Shanmugam S. and Veerappan A.R.

This paper aims to present the numerical analysis of displacements, forces and bend angles of three different structural designs of a soft actuator using the finite element…

Abstract

Purpose

This paper aims to present the numerical analysis of displacements, forces and bend angles of three different structural designs of a soft actuator using the finite element method. The results of this analysis help understand the physical behavior of the soft pneumatic actuator.

Design/methodology/approach

The soft actuator is designed using commercial modeling software, and the design of the actuator is analyzed using ABAQUS 19.0 with a standard implicit nonlinear analysis. There are three types of structural designs for actuators, namely, rectangular-base model, trapezoidal-base model and the trapezoidal model considered in the present study.

Findings

Maximum displacement, force and bend angle are observed in the rectangular-base model at various pressure levels.

Originality/value

The development of novel designs of the soft pneumatic actuator to undertake a comparative analysis of displacement, force and bend angle.

Details

World Journal of Engineering, vol. 20 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 8 April 2021

Chengxi Zhang, Jin Wu, Ran Sun, Mingjiang Wang and Dechao Ran

The purpose of this paper is to study the general actuator modeling in spacecraft attitude control systems.

Abstract

Purpose

The purpose of this paper is to study the general actuator modeling in spacecraft attitude control systems.

Design/methodology/approach

The proposed module in this paper provides various non-ideal factors such as the second-order dynamic time response, time-delay, bias torques, dead-zones and saturation. The actuator module can make the simulation as close to the practical situation as possible.

Findings

This paper presents a practical integrated module for the simulation of attitude control algorithms. Based on theoretical modeling, we give simulation modules and numerical examples. The proposed model can be directly used in spacecraft control simulation. Instead of considering only a few of them, it makes the simulation more convincing. Though it may not be perfect, it is better than totally ignoring the actuator dynamics.

Originality/value

The authors provide an integrated actuator model for spacecraft attitude control simulation, considering as many nonlinear factors as possible once time.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 9 July 2021

Xinjie Wang, Yan Cheng, Huadong Zheng, Yihao Li and Caidong Wang

Currently, rehabilitation medical care is expensive, requires a large number of rehabilitation therapist and which can only limit in the fixed location. In addition, there is a…

Abstract

Purpose

Currently, rehabilitation medical care is expensive, requires a large number of rehabilitation therapist and which can only limit in the fixed location. In addition, there is a lack of research on the structure optimization and theoretical analysis of soft actuators for hand rehabilitation. In view of the problems above, this paper aims to propose a cheap, portable, wearable soft multiple joints rehabilitation glove.

Design/methodology/approach

First, this paper determined the hyperelastic constitutive model by material tensile test. Second, the soft actuator’s internal longitudinal section shape was optimized through the comparison of three diverse chamber structures. Meanwhile, the motion model of the soft actuator is established by the finite element model analysis method. Then, this paper established the constitutive model of the soft actuator according to the torque equilibrium equation and analyzed the relationship between the soft actuator’s bending angle and the input air pressure. This paper has verified that the theoretical model is correct through the soft actuator bending test. Finally, rehabilitation gloves were manufactured according to the model and the rehabilitation performance and grasping ability of gloves were verified through experiments.

Findings

The optimization results show that the internal semicircular cavity has better performance. Then, the actuator performance is better after adding the external arc structure and optimizing the physical dimension. The experimental results show that the trajectory of the actuator conforms to the mathematical model and rehabilitation gloves can meet the needs of rehabilitation treatment.

Practical implications

Rehabilitation gloves made of actuators can help patients with hand dysfunction in daily rehabilitation training. Then, it can also assist patients with some fine and complicated hand movements.

Originality/value

This paper proposes a new type of soft rehabilitation glove, which is composed of new soft actuators and adapting pieces. The new actuator is small enough to be fitted to the knuckle of the glove to move each joint of the finger.

Details

Industrial Robot: the international journal of robotics research and application, vol. 48 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 6 May 2022

Lijia Cao, Xu Yang, Guoqing Wang, Yang Liu and Yu Hu

The purpose of this paper is to present an actuator fault detection method for unmanned aerial vehicles (UAVs) based on interval observer and extended state observer.

Abstract

Purpose

The purpose of this paper is to present an actuator fault detection method for unmanned aerial vehicles (UAVs) based on interval observer and extended state observer.

Design/methodology/approach

The proposed algorithm has very little model dependency. Therefore, a six-degree-of-freedom linear equation of UAVs is first established, and then, combined with actuator failure and external disturbances in flight control, a steering gear model with actuator failure (such as stuck bias and invalidation) is designed. Meanwhile, an extended state observer is designed for fault detection. Moreover, a fault detection scheme based on interval observer is designed by combining fault and disturbances.

Findings

The method is testified on the extended state observer and the interval observer under the failure of the steering gear and bounded disturbances. The simulation results show that the two types of fault detection schemes designed can successfully detect various types of faults and have high sensitivity.

Originality/value

This research paper studies the failure detection scheme of the UAVs’ actuator. The fault detection scheme in this paper has better performance on actuator faults and bounded disturbances than using regular fault detection schemes.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 10
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 14 August 2007

G. Krebs, A. Tounzi, F. Piriou, B. Pauwels and D. Willemot

Electromagnetic actuators, with very specific features for industrial processes, are needed much more for an increase in reliability and dynamic. To reach the wanted features, the…

Abstract

Purpose

Electromagnetic actuators, with very specific features for industrial processes, are needed much more for an increase in reliability and dynamic. To reach the wanted features, the actuator has to be designed and its performance has to be quantified with good accuracy and reasonable computation time. The purpose of this paper is to present the design and the study of a permanent magnet linear actuator.

Design/methodology/approach

The first design of the permanent magnet linear actuator has been introduced from electromechanical considerations. Then, both models utilized to study the actuator are presented: the permeance network model (PNM) and the 3D finite element model. These models are used to quantify the performance of the prototype. Owing to its speed, the influence of geometric parameters on the performances are studied by the PNM. Then, both models are used to perform calculations on global variables. A prototype of the designed actuator has been built up and the results obtained by both models are compared with the measurements.

Findings

The developed model has been used to study the behaviour of the designed actuator. Using the 3D‐FEM, the local phenomena have been highlighted as the magnetic flux density and the induced current. Then, global variables as the no load fluxes and the forces at load have been determined. The results obtained by both models have been compared together and show a good agreement. They are also very close to the measurements achieved on the prototype constructed.

Originality/value

This paper shows that it is possible to use a PNM model to design a permanent magnet linear actuator with a relative good accuracy. The PNM developed does not permit one to calculate the cogging forces and does not take into account the induced currents but it gives accurate results when the interest is focused only on the magnetostatic load operating. The comparison with the results given by 3D‐FEM and to the measurements shows a good agreement.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 11 March 2020

Nima Vaziri, Ming-Jyh Chern, Tzyy-Leng Horng and Syamsuri Syamsuri

The purpose of this study is to the modeling of the dielectric barrier discharge (DBD) actuator on the Eppler 387 (E387) airfoil in low Reynolds number conditions.

Abstract

Purpose

The purpose of this study is to the modeling of the dielectric barrier discharge (DBD) actuator on the Eppler 387 (E387) airfoil in low Reynolds number conditions.

Design/methodology/approach

A validated direct-forcing immersed boundary method is used to solve the governing equations. A linear electric field model is used to simulate the DBD actuator. A ray-casting technique is used to define the geometry.

Findings

The purposed model is validated against the former studies. Next, the drag and lift coefficients in the static stall of the E387 airfoil are investigated. Results show that when the DBD actuator is on, both of the coefficients are increased. The effects of the location, applied voltage and applied frequency are also studied and find that the leading-edge actuator with higher voltage and frequency has better improvement in the forces. Finally, the dynamic stall of the E387 with the DBD actuator is considered. The simulation shows that generally when the DBD is on, the lift coefficient in the pitch-up section has lower values and in the pitch-down has higher values than the DBD off mode.

Practical implications

It is demonstrated that using the DBD actuator on E387 in the low Reynolds number condition can increase the lift and drag forces. Therefore, the application of the airfoil must be considered.

Originality/value

The results show that sometimes the DBD actuator has different effects on E387 airfoil in low Reynolds number mode than the general understanding of this tool.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 October 2005

Georges Dumont and Christofer Kühl

The purpose of this paper is the optimisation of shape memory alloy (SMA) spring actuators. The purpose of these actuators is to control active endoscopes. The objective for such…

1247

Abstract

Purpose

The purpose of this paper is the optimisation of shape memory alloy (SMA) spring actuators. The purpose of these actuators is to control active endoscopes. The objective for such endoscopes is to minimize one patient pain during operation.

Design/methodology/approach

A range of recently published (1990‐2002) works, which aim to provide models for SMA actuators, do not focus on the simulation and on the design of such actuators. SMAs have two main characteristics, namely the phase change and non‐linear behaviour in each phase. The proposed model is based on a mixed approach combining an Euler‐Bernoulli beam model and a bi‐dimensional finite element model. It allows the modelling of plastic behaviour and drives the phase evolution in the beam cross‐section.

Findings

The physical properties of SMAs are described and modelled. A new beam model and a numerical algorithm are proposed. Preliminary results demonstrate the performance of our method on two problems and lead to determine the actuator capability. The resulting actuator model is then integrated into an optimisation process based on genetic algorithms. The overall approach provides a design tool for SMA spring actuator subjected to design constraints.

Research limitations/implications

The proposed method is only validated for our practical purposes. However, we believe that the optimisation methodology may have other implications in structure design.

Originality/value

This paper provides an optimisation approach that is valuable for scientists and engineers in engineering computations.

Details

Engineering Computations, vol. 22 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 2 August 2013

Imran Halimi Bin Ibrahim and Martin Skote

For the past decade, plasma actuators have been identified as a subset in the realm of active flow control devices. As research into plasma actuators continues to mature…

Abstract

Purpose

For the past decade, plasma actuators have been identified as a subset in the realm of active flow control devices. As research into plasma actuators continues to mature, computational modelling is needed to complement the investigation of the actuators. This paper seeks to address these issues.

Design/methodology/approach

In this study, the Suzen‐Huang model is chosen because of its ability to simulate both the charge density and Lorentz body force. Its advantages and limitations have been identified with a parametric study of two constants used in the modelling: the Debye length (λD) and the maximum charge density value (ρc* ). By varying the two scalars, the effects of charge density, body force and induced velocity are examined.

Findings

The results show that the non‐dimensionalised body force (Fb*) is nonlinearly dependent on Debye length. However, a linear variation of Fb* is observed with increasing values of maximum charge density. The optimized form of the Suzen‐Huang model shows better agreement in the horizontal velocity profile but still points to inaccuracy when compared to vertical velocity profile.

Originality/value

The results indicate that the body force still has to be modelled more extensively above the encapsulated electrode, so that the horizontal and vertical components of induced velocities are accurately obtained.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

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