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1 – 10 of 533
Article
Publication date: 1 June 2000

Gareth Monkman

Piezoelectric actuators are well established for use in expensive optical equipment. Within the last decade, relatively inexpensive piezoelectric actuators have become…

Abstract

Piezoelectric actuators are well established for use in expensive optical equipment. Within the last decade, relatively inexpensive piezoelectric actuators have become established technology in pneumatic switching and the first piezoelectrically driven impactive robot grippers are just starting to emerge. Although this article concentrates largely on the use of piezoelectric actuators for use in robot gripping systems, the potential for applications outside this field is immense.

Details

Industrial Robot: An International Journal, vol. 27 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 28 May 2021

Bin Wang, Nanyue Xu, Pengyuan Wu and Rongfei Yang

The purpose of this paper is to provide a new hydrostatic actuator controlled by a piezoelectric piston pump and to reveal its characteristics.

Abstract

Purpose

The purpose of this paper is to provide a new hydrostatic actuator controlled by a piezoelectric piston pump and to reveal its characteristics.

Design/methodology/approach

In this paper, a piezoelectric pump with passive poppet valves and hydraulic displacement amplifier is designed as a new control component in a hydrostatic actuator for high actuation capacity. A component-level mathematical model is established to describe the system characteristics. Simulation verification for cases under typical conditions is implemented to evaluate the delivery behavior of the pump and the carrying ability of the actuator.

Findings

By using the displacement amplifier and the passive distributing valves, simulation demonstrates that the pump can deliver flow rate up to 3 L/min, and the actuator controlled by this pump can push an object weighing approximately 50 kg. In addition, it is particularly important to decide a proper amplification ratio of the amplifier in the pump for better actuation performance.

Originality/value

The piezoelectric pump presented in this paper has its potential to light hydrostatic actuator. The model constructed in this paper is valid for characteristic analysis and performance evaluation of this pump and actuators.

Details

Assembly Automation, vol. 41 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 3 April 2017

Zhiqiang Yu, Qing Shi, Huaping Wang, Ning Yu, Qiang Huang and Toshio Fukuda

The purpose of this paper is to present state-of-the-art approaches for precise operation of a robotic manipulator on a macro- to micro/nanoscale.

Abstract

Purpose

The purpose of this paper is to present state-of-the-art approaches for precise operation of a robotic manipulator on a macro- to micro/nanoscale.

Design/methodology/approach

This paper first briefly discussed fundamental issues associated with precise operation of a robotic manipulator on a macro- to micro/nanoscale. Second, this paper described and compared the characteristics of basic components (i.e. mechanical parts, actuators, sensors and control algorithm) of the robotic manipulator. Specifically, commonly used mechanisms of the manipulator were classified and analyzed. In addition, intuitive meaning and applications of its actuator explained and compared in details. Moreover, related research studies on general control algorithm and visual control that are used in a robotic manipulator to achieve precise operation have also been discussed.

Findings

Remarkable achievements in dexterous mechanical design, excellent actuators, accurate perception, optimized control algorithms, etc., have been made in precise operations of a robotic manipulator. Precise operation is critical for dealing with objects which need to be manufactured, modified and assembled. The operational accuracy is directly affected by the performance of mechanical design, actuators, sensors and control algorithms. Therefore, this paper provides a categorization showing the fundamental concepts and applications of these characteristics.

Originality/value

This paper presents a categorization of the mechanical design, actuators, sensors and control algorithms of robotic manipulators in the macro- to micro/nanofield for precise operation.

Details

Assembly Automation, vol. 37 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 15 October 2018

Mohammad Azadi

The purpose of this paper is to analyze and control the flutter vibrations of a thermoelastic functionally graded material (FGM) beam subjected to follower force using the…

Abstract

Purpose

The purpose of this paper is to analyze and control the flutter vibrations of a thermoelastic functionally graded material (FGM) beam subjected to follower force using the piezoelectric sensors/actuators.

Design/methodology/approach

The beam is made of FGM properties which are functionally graded in the thickness direction according to the volume fraction power law distribution and change with temperature. As the two sides of the beam are located in two different temperatures, the thermoelastic effects are considered in the governing equation of motion. The beam is fixed from one end and a follower force is applied to the free end of it. An active control is applied to the system to suppress the flutter vibration of the beam.

Findings

After the simulation, the effects of the temperature gradient, magnitude of the follower force and piezoelectric lengths on the dynamic stability and the response of the system are studied. Simulation results show that the vibration of the system has been damped rapidly by applying the controller to the system.

Originality/value

Stability analysis and robust control of a thermoelastic FGM beam subjected to a follower force using piezoelectric sensors and actuators is the novelty of this study.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 2 May 2017

S. Ahmad Fazelzadeh and Emad Azadi

The purpose of this paper is to analyze and control the thermally induced vibration of orbiting smart satellite panels, which have been modeled as functionally graded…

Abstract

Purpose

The purpose of this paper is to analyze and control the thermally induced vibration of orbiting smart satellite panels, which have been modeled as functionally graded material (FGM) beams.

Design/methodology/approach

It is assumed that the satellite moves in a circular orbit and has pitch angle rotation maneuver. Rapid temperature changes at day–night transitions in orbit generate time dependent bending moments that induce vibrations in the appendages. So, the heat radiation effects on the appendages should be considered. The thermally induced vibrations of the appendages and the nonlinear heat transfer equation are coupled and should be solved simultaneously. So, the governing equations of the motion are nonlinear and very complicated ones. A robust passivity-based controller is proposed to control the satellite maneuver and appendages vibrations, using piezoelectric sensors/actuators.

Findings

After the simulation, the effects of the heat radiation, piezoelectric actuators and piezoelectric locations on the response of the system are studied. The results of dynamic response and thermal analysis show that the radiation thermal effects are coupled with structure dynamic. These effects induce the vibration. Also, the effectiveness and the capability of the controller are analyzed. The results of the simulation show that the robust passivity-based control can ensure that the satellite rotates in the desired trajectory and vibrations of the appendages are damped. It demonstrates that the proposed control scheme is feasible and effective.

Originality/value

The paper is the basis of deriving the governing equations, thermal analysis and a robust control system design of a smart satellite with FGM panels.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 4 July 2016

Antonios X. Lalas, Nikolaos V. Kantartzis and Theodoros D. Tsiboukis

Metamaterials are artificially tailored complex media with extraordinary properties, not available in nature. Due to their unique performance, they are considered as a…

Abstract

Purpose

Metamaterials are artificially tailored complex media with extraordinary properties, not available in nature. Due to their unique performance, they are considered as a crucial component of modern radio-frequency technology, especially in the THz regime. However, their lack of wide spectral bandwidths introduce constraints for realistic applications. The purpose of this paper is to propose piezoelectric micro-electromechanical systems (MEMS) actuators to modify the shape of electric field-driven LC (ELC) resonators. A THz modulation capability is revealed by connecting/disconnecting the associated metal parts.

Design/methodology/approach

Piezoelectric MEMS actuators are proposed to provide the desired bandwidth enhancement along with THz modulation. Two setups with different degrees of freedom in altering the behaviour of the novel modulator are investigated. A variety of numerical data, acquired via the finite element method, substantiate the advantageous characteristics of the proposed structures.

Findings

The novel devices enable the modification of the structural features of an ELC-based complex medium, unveiling in this manner a significant THz modulation capability along with improved bandwidth tunability. Two discrete cases are presented involving different degrees of freedom to shape the overall performance of the metamaterial modulator.

Originality/value

Development of a THz modulator, which utilises metamaterials as its fundamental component. Incorporation of tunable piezoelectric metamaterials into THz technology allowing increased reconfigurability. Bandwidth enhancement of metamaterial systems and alternative design via multiple controllable gaps enabling more degrees of freedom for design purposes.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 35 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 December 2003

M. Brown, N. Tsagarakis and D.G. Caldwell

This paper reviews the current status of devices for use as exoskeletons for assisting or constraining human movements. Applications include teleoperation and force…

2901

Abstract

This paper reviews the current status of devices for use as exoskeletons for assisting or constraining human movements. Applications include teleoperation and force augmentation to allow people to operate more easily or more efficiently in a variety of situations, including military and emergency service applications.

Details

Industrial Robot: An International Journal, vol. 30 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 September 2006

Qinglei Hu

To provide an approach to active vibration reduction of flexible spacecraft actuated by on‐off thrusters during attitude control for spacecraft designers, which can help…

Abstract

Purpose

To provide an approach to active vibration reduction of flexible spacecraft actuated by on‐off thrusters during attitude control for spacecraft designers, which can help them analysis and design the attitude control system.

Design/methodology/approach

The new approach includes attitude controller acting on the rigid hub, designed by using pulse‐width pulse‐frequency modulation integrated with component command technique, and the piezoelectric material elements as sensors/actuators bonded on the surface of the beam appendages for active vibration suppression of flexible appendages, designed by optimal positive position feedback (OPPF) control technique. The OPPF compensator is devised by setting up a cost function to be minimized by feedback gains, which are subject to the stability criterion at the same time, and an extension to the conventional positive position feedback control design approach is investigated.

Findings

Numerical simulations for the flexible spacecraft show that the precise attitude control and vibration suppression can be accomplished using the derived vibration attenuator and attitude control controller.

Research limitations/implications

Studies on how to control the on‐off actuated system under impulse disturbances are left for future work.

Practical implications

An effective method is proposed for the spacecraft engineers planning to design attitude control system for actively suppressing the vibration and at the same time quickly and precisely responding to the attitude control command.

Originality/value

The advantage in this scheme is that the controllers are designed separately, allowing the two objectives to be satisfied independently of one another. It fulfils a useful source of theoretical analysis for the attitude control system design and offers practical help for the spacecraft designers.

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 5
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 April 2005

Jaroslav Mackerle

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming…

5101

Abstract

Purpose

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

Design/methodology/approach

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Findings

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Originality/value

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

Details

Engineering Computations, vol. 22 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 August 2004

Tien‐Fu Lu, Daniel C. Handley, Yuen Kuan Yong and Craig Eales

Micromanipulation has enabled numerous technological breakthroughs in recent years, from advances in biotechnology to microcomponent assembly. Micromotion devices commonly…

1787

Abstract

Micromanipulation has enabled numerous technological breakthroughs in recent years, from advances in biotechnology to microcomponent assembly. Micromotion devices commonly use piezoelectric actuators (PZT) together with compliant mechanisms to provide fine motions with position resolution in the nanometre or even sub‐nanometre range. Many multiple degree of freedom (DOF) micromotion stages have parallel structures due to better stiffness and accuracy than serial structures. This paper presents the development of a three‐DOF compliant micromotion stage with flexure hinges and parallel structure for applications requiring motions in micrometres. The derivation of a simple linear kinematic model of the compliant mechanism is presented and simulation results before and after calibration are compared with results from finite element (FE) modeling and experiments. The position control system, which uses an experimentally determined constant‐Jacobian, and its performance are also presented and discussed.

Details

Industrial Robot: An International Journal, vol. 31 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

1 – 10 of 533