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The purpose of this paper is to develop lightweight actuators in order to replace conventional hydraulic/pneumatic actuators and to apply the actuation system to a small flying vehicle.

A new type of control surface using a piezo‐composite actuator for a small flying vehicle has been designed and manufactured. The piezo‐composite actuator is composed of a piezoelectric ceramic layer, a carbon/epoxy layer and glass/epoxy layers. Through this, the miniaturization and weight reduction of the actuation systems for flying vehicle can be achieved. A simple model of the control surface has been manufactured and evaluated through experiments.

The performance test results showed that the developed actuator can produce stable angle of attack independent of the applied loading. A radio controller for the actuator was developed to control the motions wirelessly. It was found that the piezo‐composite actuator and its integrated controller system have a possibility to be used not only as a small flying vehicle but also as a control surface actuator of a small unmanned flying robot through the miniaturization of power supply and control system.

The paper describes the procedures of designing and manufacturing smart structure application of the piezo‐composite actuator with performance evaluation and comparison method. It is expected that piezo‐composite actuator can be used as a small flying vehicle control surface actuator through the miniaturization of power supply and control system with the use of the integrated radio controller MIPAD.

Wall climbing robots' volume is needed to be very small in fields that workspace is limited, such as anti‐terror scouting, industry pipe network inspecting and so on. The purpose of this paper is to design a miniature wall climbing robot with biomechanical suction cups actuated by shape memory alloy (SMA) actuators.

Based on characteristics of biologic suction apparatuses, the biomechanical suction cup is designed first. Theory analysis of the suction cup is made considering elastic plate's deflection and SMAs constitutive model. A triangular close linkage locomotion mechanism is chosen for the miniature robot because of its simple structure and control. The robot's gait, kinematics, and control system are all illustrated in this paper.

Experiments indicate that the suction cup can be used as an adhesion mechanism for miniature wall climbing robots, and the miniature robot prototype with biomechanical suction cups can move in straight line and turn with a fixed angle on an inclined glass wall.

This paper describes how a miniature wall climbing robot with biomechanical suction cups actuated by SMA without any air pump is designed.

The aim of the research is to perform an accurate micromanipulation task, the assembly of a lens system, implementing safe procedures in a flexible microrobot‐based workstation for micromanipulation.

The approach to the micromanipulation research issue consists in designing and building a micromanipulation station based on mobile microrobots, with 5 degrees of freedom and a size of a few cm³, capable of moving and manipulating by the use of tube‐shaped and multilayered piezo‐actuators. Controlled by visual and force/tactile sensor information, the micro‐robot is able to perform manipulation with a motion resolution down to 10 nm in a telemanipulated or semi‐automated mode, thus freeing human operators from the difficult task of handling minuscule objects directly. Equipped with purposely‐developed grippers, the robot can take over high‐precise grasping, transport, manipulation and positioning of mechanical or biological micro‐objects. A computer system using PC‐compatible hardware components ensures the robot operation in real‐time.

The robots and the grippers described in this paper are highly interesting tools. Even if each specific application may require specific modifications, the proposed solution is extremely versatile, due to the ability to manipulate with a very large stroke (being the size of the base the robot works on) with a very high motion resolution. These positive aspects do make the robots very suitable also for working in a scanning electron microscope, for wafer inspection in a laboratory, and so on.

Future work will include modifications to the existing system in order to enhance the flexibility of the workstation: e.g. other robots and other tools with different characteristics will be designed and fabricated. Research efforts will be devoted in particular to further miniaturization of the actuators.

This workstation can be used as a platform for assembling novel prototypes, and as a test bench for testing new assembly procedures or new products, e.g. the lens assembly procedure described in this work, even if not suitable for mass production, was useful to assess the performance of the two‐lenses assembly system itself, compared to standard systems with just one lens.

The system proves that the development of mobile micro‐robots is a promising approach to realise very small and flexible tools useful for different applications. By means of its intuitive teleoperation mode, the system enables the user to work in the micro‐world; due to the force feedback the user is almost immersed into the micro‐world and gets a sense for the handled object.

Approaches for a miniaturisation of electrical machines that are based on an electromagnetic principle have to overcome numerous challenges. Some of these are only a result of the rules of growth (or shrinkage), some are a result of the micro technological fabrication processes. This paper aims to give an overview of the current state of the art including various examples of linear and rotating micro actuators that have been realised.

The paper presents details of further miniaturisation by using thin film technology for depositing and structuring soft magnetic and hard magnetic material as well as copper for conductors and insulation.

There are numerous limitations for the miniaturisation with respect to material properties, friction/guidance, etc. and this paper illustrates ways to overcome these limitations.

The paper presents a compact overview on the achievements gained in 12 years of research within a collaborative research centre of the German DFG.

The purpose of this paper is to review the current application areas of shape memory alloy (SMA) actuators in intelligent robotic systems and devices.

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.

SMA actuators find wide applications in various facets of robotic equipments. Selecting a suitable shape, fast heating and cooling method and better intelligent control technique with or without feedback devices could optimize its performance.

The frequency of SMA actuation purely depends on the rate of heat energy added to and removed from the actuator, which in turn depends upon interrelated nonlinear parameters.

For increasing the dof of robots, number of actuators also have to be increased that leads to complex control problems.

Explains the suitability of SMA as actuators in smart robotic systems, possibility of miniaturisation. It also highlights the difficulties faced by the SMA research community.

To predict the influence of inherent microfabrication and operating environmental influences on the performance of capacitive type sensors and actuators so that one can tune the performance and carry out more realistic designs.

When the sensors and actuators are micromachined or microfabricated, they are subjected to special problems that are characteristic to microdimensions. The important concerns are the influence of microfabrication process on the material properties and influence of operating environment on the system behavior. Hence, this paper proposed a way of quantifying and modeling the influence of inherent limitations of microfabrication and operating environment for the better design of micromachined capacitive type sensors and actuators. The methodology applies the modeling the variation of the elastic property of the system due to above influences through elastic stiffening and weakening concepts. The approach includes the application of boundary conditioning concept through Rayleigh energy method.

The microfabrication process and electrostatic field can alter significantly both static and dynamic behavior of the device. The performance of the device could also be tuned through these influences.

As the displacement of the sensors is expected to be small, linear approach is applied. The sensitivity, output range, operating limits and natural frequencies of the sensor can be easily controlled by varying the process and operating environmental influences.

Improved and more realistic design of microfabricated capacitive type sensors and actuators for many applications, such as, pressure sensors, microphones, microspeakers, etc.

A simple and easy way of modeling and quantifying the influence of process and operating environment was proposed for the betterment of design. The proposed design method can be applied for any micromachined or microfabricated capacitive type sensors and actuators so that varying sensitivities, output ranges and natural frequencies could be obtained. Over the last few years, newly emerging micro‐electro‐mechanical‐systems (MEMS) technology and micro‐fabrication techniques have gained popularity and importance in the miniaturization of a variety of sensors and actuators. The proposed technique is very useful in making the field of MEMS more matured as it attempts to model the problems that are unique to MEMS environment.

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.

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.

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.

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.