Actuators and Sensors

This work aims to develop a classification model for drives actuators features depending on their feature. The proposed model consists of nine levels that include the most common actuators, which in turn will facilitate easy identification of relationships and ease of finding alternatives. On the basis of the proposed classification, an information model of actuator alternatives has been created, which reflects key information about them. The created model will provide an opportunity to reduce the design time of the actuators.

We have fabricated an ionic polymer metal composite (IPMC) actuator with polyaniline and graphene oxide composite as electrode over the widely used Nafion membrane, using a simple solvent mixing and dip coating process thus avoiding the costly and time-consuming platinum coating process. The proton conductivity, dielectric constant, water uptake potential, ionic transference number and X-Ray diffraction studies have been carried out along with monitoring the tip displacement of the actuator with varying D.C. voltages and time.

This paper presents an enhanced haptic-enabled master-slave teleoperation system which can be used to provide force feedback to surgeons in minimally invasive surgery (MIS). One of the research goals was to develop a combined-control architecture framework that included both direct force reflection (DFR) and position-error-based (PEB) control strategies. To achieve this goal, it was essential to measure accurately the direct contact forces between deformable bodies and a robotic tool tip. To measure the forces at a surgical tool tip and enhance the performance of the teleoperation system, an optical force sensor was designed, prototyped, and added to a robot manipulator. The enhanced teleoperation architecture was formulated by developing mathematical models for the optical force sensor, the extended slave robot manipulator, and the combined-control strategy. Human factor studies were also conducted to (a) examine experimentally the performance of the enhanced teleoperation system w...

Presentation overview of Failure analysis of a helicopter rotor system. This presentation was performed by Md. Shahin Hossain (199012), and me Shariful Islam (199024). Department of Materials and Metallurgical Engineering at Dhaka University of Engineering and Technology, Gazipur.

We present MorePhone, an actuated flexible smartphone with a thin-film E Ink display. MorePhone uses shape memory alloys to actuate the entire surface of the display as well as individual corners. We conducted a participatory study to determine how users associate urgency and notification type with full screen, 1 corner, 2 corner and 3 corner actuations of the smartphone. Results suggest that with the current prototype, actuated shape notifications are useful for visual feedback. Urgent notifications such as alarms and voice calls were best matched with actuation of the entire display surface, while less urgent notifications, such as software notifications were best matched to individual corner bends. While different corner actuations resulted in significantly different matches between notification types, medium urgency notification types were treated as similar, and best matched to a single corner bend. A follow-up study suggested that users prefer to dedicate each corner to a specific type of notification. Users would like to personalize the assignment of corners to notification type. Animation of shape actuation significantly increased the perceived urgency of any of the presented shapes.

This work aims to develop a classification model for drives actuators features depending on their feature. The proposed model consists of nine levels that include the most common actuators, which in turn will facilitate easy identification of relationships and ease of finding alternatives. On the basis of the proposed classification, an information model of actuator alternatives has been created, which reflects key information about them. The created model will provide an opportunity to reduce the design time of the actuators.

The Internet of Things (IoT) will connect not only computers and mobile devices, but it will also interconnect smart buildings, homes, and cities. The integration of IoT with Fog and Cloud Computing can bring not only the computational requirements, but they also enable IoT services to be pervasive, cost-effective, and can be accessed from anywhere and at any time. In any IoT application, communications are crucial to deliver the required information, for instance to take actions during crisis events. However, IoT components such as Gateways, usually referred as IoT nodes, will introduce major security challenges as they contribute to increase the attack surface, preventing the IoT to deliver accurate information to final users. In this paper, we present a methodology to develop an Intrusion Detection System based on Anomaly Behavior Analysis to detect when an IoT network node is being compromised. Our preliminary experimental results show that our approach accurately detects known and unknown anomalies due to misuses or cyber-attacks, with high detection rate and low false alarms.

An efficient computational approach based on a generalized unconstrained approach in conjunction with isogeometric analysis (IGA) are proposed for dynamic control of smart piezoelectric composite plates. In composite plates, the mechanical displacement field is approximated according to the proposal model using isogeometric elements and the nonlinear transient formulation for plates is formed in the total Lagrange approach based on the von Kármán strains and solved by Newmark time integration. Through the thickness of each piezoelectric layer, the electric potential is assumed linearly. For active control of the piezoelectric composite plates, a close-loop system is used. An optimization procedure using genetic algorithm (GA) is considered to search optimal design for actuator input voltages. Various numerical examples are investigated to show high accuracy and reliability of the proposed method.

The ambitions of current neuroscience, understanding neurological disease progression and mapping the connectome, demonstrate a need for safe in vivo tools for creating intricate maps of brain circuitry. Present in vivo contrast agents are often limited by their specificity, uptake, resolvability, and/or clearance. We describe an aptamer-functionalized sensor for high-resolution imaging that can switch imaging targets by an induced multi-stage aptamer reaction. Included are synthetic methods as well as calculations of sensor efficacy based on known kinetics. Calculations show that 10 distinct targets may be imaged in a living brain at the submicron scale within 42 hours.

Gecko foots have inspired researchers to develop designs that can help robots to tread vertically oriented surface. These nanobots find many applications as they can perform a lot of operations more efficiently and also lower the cost of such operations. These can be employed in various fields: medical, industrial etc. Gecko lizards use dry adhesion van der Waals forces to climb walls produced by their spatular stalks attached on setae. The design of a 3D MEMS model of an electrothermally actuated gecko foot is presented in this paper. The working of a single microhair (with nanohairs attached to it) is discussed and the two designs, one with actuation and one without are compared.

In this work, novel Shape Memory Alloy (SMA)-based actuators are proposed to provide angular displacements in both clockwise and counterclockwise directions with compliance. A bidirectional SMA rotating actuator is fabricated using a rotating frame and two SMA wire-based actuating units similar to human skeletal muscle systems without any additional complicated rotational driving mechanism. These actuating units are activated independently to provide bidirectional rotary motions by using sequentially coordinated electrical inputs. The mechanical, thermal, and electrical properties of the bidirectional SMA rotating actuator are also characterized experimentally. The design and manipulation of the proposed actuator are experimentally verified with simple open-loop and closed-loop control strategies.

This paper presents a modified integral sliding surface, sliding mode control law for pneumatic artificial muscles. The cutoff frequency tuning parameter λ is squared to increase the gradient from absement (integral of position) to position and higher derivatives to reflect the more dominant terms in the actuator dynamics. The sliding mode controller is coupled with proportional and integral action compensation. The control system is sufficiently robust so that use of an observer and input-output feedback linearization are not required. Closed-loop control experiments are compared with traditional sliding mode controller designs presented in the literature for pneumatic artificial muscles. Experiments include the tracking of sinusoidal waves at 0.5 and 1 Hz, tracking of square-like waves with seventh-order trajectory transitions at a rate of 0.2 Hz without and with a steady-state period of 10 seconds, as well as a step input response. These experiments indicate that the control law ...

Photo‐crosslinkable side‐chain liquid‐crystalline polymers (LCPs) containing photoreactive benzophenone cores are synthesized in order to obtain their corresponding side‐chain liquid‐crystalline elastomers (LCEs). This strategic synthesis allows thin elastomeric films and their integration into microsystems for actuators and micromachines to be obtained. As an example of this principle, a gripper was developed. The position of its arms can be changed by applying voltages from 1.5 to 3.5 V at different rates. Small changes in the liquid‐crystalline elastomer film cause strains of up to 150% in the microdevice and the capacity to move up to 400 times its own mass due to the nematic‐to‐isotropic transformation.magnified image

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This paper introduces the Shape Adaptive Blades for Rotorcraft Efficiency (SABRE) Horizon 2020 research program and presents initial comprehensive analysis results on the efficacy of adapting blade shapes as a means of reducing rotorcraft power requirements and emissions. The aims of the research program are introduced, followed by discussion of the six different morphing concepts that will be explored. The morphing mechanisms are based on active camber, chord extension, twist, and active tendon morphing technologies. SABRE will explore the use of these concepts individually and in combination, for rotor quasi-steady configuration-type morphing and up to 2/rev actuation of some of the mechanisms, with the objective being to find the best balance between emissions reductions versus complexity and added weight. Initial investigations into the potential power reductions compared to the baseline full-scale BO-105 main rotor achievable with the morphing concepts were performed using Blad...

Pneumatic artificial muscles (PAMs) belong to the group of nonconventional actuators with remarkable force/weight ratio that can be used for the construction of soft mechanisms safe in contact with humans. In order to be able to design an effective control of 2-link soft robot arm actuated with PAMs, a dynamic model of this system needs to be derived. We use a PAM dynamic model derived using first principles modeling (for contraction, pressure, and air flow dynamics) and ANFIS-based approximation based on the experimental data for the muscle force function. To derive the dynamics of the robot arm, we use Lagrangian mechanics approach for planar arm with the inertial and mass data based on the 3D CAD model. To validate the complete dynamic model of the soft robot arm, we used a gravity test (without PAM actuation) and pulse excitation for PAM control. The results confirm good validity of the dynamic model for all relevant variables (joint angles, muscle contractions, and pressures) as well as the dynamic coupling between the joints.

The influence of the rate of dilution of the mesogens along the polymer backbone on the conformation and the structure of two different side-on mesogens polysiloxanes are studied using neutronscattering techniques. The average backbone conformation in the nematic and smectic C phases is deduced from small-angle neutron-scattering measurements. An inversion in the backbone conformation from prolate in the nematic phase to highly oblate in the smectic phase is evidenced. Distribution profiles of polysiloxane main chains are calculated from neutron diffraction experiments in the smectic phase. A transition in the confinement of the main chain within the layers has been demonstrated: the polymer backbone can be segregated between the layers, but also present in the middle part of the mesogenic layers.

The paper presents an effective numerical approach for modeling and optimizing the ceramic volume fraction distribution of functionally graded (FG) plates in the thermo-mechanical environment. Ceramic volume fraction design variables at control points whose coordinates are located along the plate thickness by Greville abscissae are used to describe the material distribution using the B-spline basis functions. Continuously altering macroscopic material properties can therefore be easily captured by selecting a proper order of these B-spline functions without any extra terms. The temperature-dependent material properties are then evaluated by either the rule of mixture or the Mori-Tanaka scheme. A non-uniform rational B-splines (NURBS)-based isogeometric finite element model associated with the third-order shear deformation theory (TSDT) is utilized for the static analysis of the FG plates. A recently proposed adaptive hybrid evolutionary firefly algorithm (AHEFA) is employed to solve compliance minimization problems with volume constraints. This algorithm effectively enhances the trade-off between the global and local search abilities, the solution accuracy and the convergence speed are thus improved dramatically. Several numerical examples are examined to confirm the effectiveness and robustness of the present method.

Abstract: An experimental and numerical research project was developed to address the effect of the level of transverse post-tensioning (TPT) and the number of the transverse diaphragms on the performance of side-by-side box-beam bridges using unbonded carbon fiber composite cables (CFCC). The experimental program included the construction, instrumentation, and testing of one half-scaled 30 skew bridge model. The numerical program investigated the sensitivity to longitudinal cracking for a wide range of side-by- ...

Among many rotating machinery vibration sources, there is one due to resonance, when the machine operation frequency crosses the natural frequency region. This study proposes a smart bearing that employs shape memory alloy NiTi helical springs for vibration-level reduction. This smart bearing is capable of dynamically changing its stiffness during machine acceleration or deceleration, keeping its natural frequency far from resonance. Activated by Joule effect and cooled by forced air convection, the prototype installed in horizontal rotating machinery reaches reduction of vibration amplitude of about 63% (root mean square) and 73% (Peak) at critical speed, with response time between 12–15 s. Compared with the results of the reference articles, satisfactory amplitude reduction and better response time were observed.

Shape memory alloy (SMA) actuators generally have a fast response time when heated. However, the return stroke during cooling can be slow and has been a hindrance to the application of SMA actuators in different areas such as robotic hands. Thus, a novel finger-like antagonistic SMA actuator design is presented in this paper. By using different thermal shape setting processes, one SMA actuator was designed to take a curved shape when heated. This actuator was antagonistically coupled to a different actuator that took a straight shape when heated. Thus, alternately heating each actuator caused the finger-like manipulator to flex and extend rapidly. A comparison study was performed between the novel antagonistic design and a single actuator which showed that the both designs applied approximately the same force with the same velocity when flexing. However, the antagonistic design was able to extend, or open, more rapidly with statistical significance. This was demonstrated for 1.5mm, 1.9mm, and 3.0mm SMA actuator diameters.

In this paper we give a new control model based on the so called computedtorque method for the control of a 2 degrees of freedom orthosis for the rehabilitation of the lower limb, the AIRGAIT exoskeleton's leg orthosis. The actuation of the AIRGAIT is made through self-made pneumatic muscles. For this reason this work starts with the static and dynamic characterization of our pneumatic muscles. The followed approach is based on the analytical description of the system. For this, we describe the pneumatic muscles behaviour with an easy-invertible polynomial fit function in order to model its non-linear trend. We give a geometrical model of the mechanical system to compute the length between the attachments of the pneumatic muscles to the structure for every angles assumed by the two joints. We evaluate through Newton-Euler equation the couples at the joints for each values of the angles. At last we show some validation tests in order to characterize the functioning of the proposed control model on the actuation of the orthosis.

An Emergency Response (ER) Cyber-Physical System (CPS) to avoid landslides and survey areas located on or near slopes is introduced that handles two problems: electronic waste disposal, and environmental disasters. Uncomplicated detection circuits using salvaged components can pinpoint floods in impoverished regions. CPSs simplify hazard prediction and mitigation in disaster supervision. Nonetheless, few green practices and efforts have been accomplished in this regard. Recent technical advances help landslides studies and the evaluation of suitable risk alleviation measures. This work addresses in situ meters, and cameras to observe ground movements more accurately. The ER-CPS identifies and can help mitigate landslides using techniques based on motion detection that can productively predict and monitor the zone conditions to classify it, and the landslide-related data can be transmitted to inspecting stations to lessen the erosion/sedimentation likelihood while increasing security.

Generally in a white light-emitting diode (LED), a phosphor slurry is placed around the semiconductor chip or the phosphor is conformally coated over the chip to covert the narrowband, short-wavelength radiation to a broadband white light. Over the past few years, the remote-phosphor method has provided significant improvement in overall system efficiency by reducing the photons absorbed by the LED chip and reducing the phosphor quenching effects. However, increased light output and smaller light engine requirements are causing high radiant energy density on the remotephosphor plates, thus heating the phosphor layer. The phosphor layer temperature rise increases when the phosphor material conversion efficiency decreases. Phosphor layer heating can negatively affect performance in terms of luminous efficacy, color shift, and life. In such cases, the performance of remote-phosphor LED lighting systems can be improved by suitable thermal management to reduce the temperature of the phosphor layer. To verify this hypothesis and to understand the factors that influence the reduction in temperature, a phosphor layer was embedded in a perforated metal heatsink to remove the heat; the parameters that influence the effectiveness of heat extraction were then studied. These parameters included the heatsink-to-phosphor layer interface area and the thermal conductivity of the heatsink. The temperature of the remote-phosphor surface was measured using IR thermography. The results showed that when the heat conduction area of the heatsink increased, the phosphor layer temperature decreased, but at the same time the overall light output of the remote phosphor light engine used in this study decreased due to light absorption by the metal areas.

The term liquid crystal elastomer (LCE) describes a class of materials that combine the elastic entropy behaviour associated with conventional elastomers with the stimuli responsive properties of anisotropic liquid crystals. LCEs consequently exhibit attributes of both elastomers and liquid crystals, but additionally have unique properties not found in either. Recent developments in LCE synthesis, as well as the understanding of the behaviour of liquid crystal elastomers—namely their mechanical, optical and responsive properties—is of significant relevance to biology and biomedicine. LCEs are abundant in nature, highlighting the potential use of LCEs in biomimetics. Their exceptional tensile properties and biocompatibility have led to research exploring their applications in artificial tissue, biological sensors and cell scaffolds by exploiting their actuation and shock absorption properties. There has also been significant recent interest in using LCEs as a model for morphogenesis....

Worldwide, stored grain pests are massively infesting most stored crops and their by-products. The main losses are due to infestation of these pests occurring on various carriers just prior to harvest, during storage or shipping. Methyl bromide and phosphine fumigation have been widely used for phytosanitary treatment of stored grains but are recognized as highly effective in depleting ozone, and similarly, residue-free grains are important for thermal disinfection. Solarization is one of the best ways to manage and disinfect crops, the traditional solarization methods are already practised by farmers but are inefficient to kill all stages of pests and require additional land exposed to the sun. In this work, thermal disinfection systems using solar heaters are proposed, designed, and developed to offset the actual lethal heat window. For the experiment work, the solar heater boxes were constructed in an octagon shape with 135 o at the base for trapping maximum heat inside the solar the heater box. The characteristics of the proposed system proved simpler, faster, and inexpensive but equally effective to achieve the desired results in terms of heat generation and seed moisture.

The main disadvantage of the pneumatic artificial muscles (PAMs) is that their dynamic behaviour is highly nonlinear. Designing an adequate control mechanism for this highly non-linear system needs precise modelling. This paper presents our new, accurate and simple approximation model of PAM, comparing with measured and literary data

The newest and most promising type of pneumatic actuators is the pneumatic artificial muscle (PAM). Different designs have been developed, but the McKibben muscle is the most popular and is made commercially available by different companies (e. g. Fluidic Muscle manufactured by Festo Company). The most often mentioned characteristic of PAMs is the force as a function of pressure and contraction. In this paper our newest function approximation for the force generated by Fluidic Muscles is shown that can be generally used for different muscles made by Festo Company.

Pneumatic artificial muscles (PAMs) as soft, lightweight and compliant actuators have great potential in applications for the actuations of new types of robots and manipulators. The favourable characteristics of fluidic muscles, such as high power-to-weight ratio and safe interaction with humans are also very suitable during the process of musculoskeletally rehabilitating patients and are often used in making artificial orthoses. This technology, despite the problems of control relatng to nonlinear phenomena, may also have wide future applications within industrial and mechatronic systems. This paper presents several experimental systems actuated by PAMs, which have been designed as test models within the fields of mobile robots, mechatronics, fluid power systems and the feedback control education of mechanical engineering students. This paper first presents the design and construction of a four legged walking robot actuated by pneumatic muscles. The robot has a fully autonomous system with a wireless application platform and can be controlled using a cell phone. Then the paper describes the design and construction of the prototype of an actively-powered ankle foot orthosis. This orthosis device actuated by a single PAM is able to provide the appropriate functions required during the rehabilitations of patients and the loss of mobility. Then the paper focuses on the design and control of a ball and beam system with an antagonistic muscle pair for generating the necessary torque for beam rotation. This mechatronic balancing mechanism falls into the category of unstable, under-actuated, multivariable systems with highly nonlinear dynamics. The final section of the article presents the design and control of a single-joint manipulator arm with pneumatic muscle actuators that enable some new features for the controlled systems.

The Display and Beam Steering Thrust of the AFOSR Liquid Crystal MURI addressed key materials and device technology issues affecting performance of liquid crystal (LC) electro-optic (EO) devices, particularly device structures useful in information Displays and for Laser Beam Steering and Switching. Two basic themes were development of bulk LCs having high performance characteristics (nematic LCs, and chiral smectic LC devices having analog response), and development of novel LC electro-optic structures. Research on novel device structures led to advances in LC alignment and on photonic band-gap materials.

There is heightened interest in research to develop materials and devices that achieve greater energy storage capacity, power density and increased energy efficiency. This work analyses the performance of a novel energy storage device, the pneumatic strain energy accumulator (pSEA), which is designed to exploit the advantageous aspects of the non-linear behaviour of elastomeric materials. An analytical method for simultaneously characterising the pneumatic energy and strain energy stored in a strain energy accumulator (SEA), and more generally for pneumatic and strain energy systems, has been employed. Component efficiency along with the expansion and contraction pressures of the pSEA are determined experimentally so that a system level efficiency calculation can be performed. Incorporating uncertainty analysis, the efficiencies of the SEA are measured to be consistently over 93% in over 800 cycles of testing. The steady-state expansion and contraction pressures of the accumulator have steady-state values with errors of less than 3 hundredths of a kilopascal from their means.

The aim of this study is to propose a methodology to actively control the vibration of functionally graded plates, with the help of piezoelectric actuators and sensors. The study relays on the classical plate theory to analytically formulate the governing equation of motion, which is then expanded to derive a space state equation of the model. The material properties of the FG plate are assumed to vary along the thickness direction. In order to improve the damping effectiveness, the location of the piezoelectric sensors and actuators is optimally determined using the H2 norm. The necessary control voltage was determined based on optimal LQR and LQG controllers.

One of the most severe failures in an aircraft provided with turboprops is an airscrew blade loss. Design precautions must be taken to minimize the hazards to the airplane in the event of a propeller blade failure. One of the hazards which must be considered include structural damage, and the airplane must be designed for the imbalance loads resulting from the failure. The structure must absorb the dynamic loads while the rest of the aircraft continues flying. If the energy of the phenomenon increases until it behaves uncontrollably, the engine could be detached from the structure. There must be devices which react to decrease the risks of critical failure for the rest of the structure. This article is mainly focused on the response of the structure after the break of a propeller blade until the end of the phenomenon. The detached propeller blade is also studied in terms of the size that is lost and its influence on the system behavior. Moreover the effects of stiffness and strength changes on the engine mounting system are analyzed. The research covers different parameters which can influence the phenomenon, including flight condition, propeller rotational frequency, and angular position where the blade is lost. The engine and the engine mounting system have been modeled in a finite element method (FEM). The simulations are run in an explicit solver and the simulation methodology includes failure of elements and non-linear behavior.

One of the common methods of structural damage detections and identification of location and severity of the damage in structures is investigation of changes in modal parameters before and after damage. These methods which are mostly based on optimization techniques use an objective function based on natural frequencies and mode shapes. This paper reviews previous researches in damage detection techniques based on modal parameters and common objective functions used in the optimization stage in the damage detection process. To this end, damage detection methods based on natural frequency, mode shape, curvature mode shape and both of mode shape and natural frequency are reviewed. In the following, due to high importance of objective function in the damage detection process, objective functions based on modal assurance criterion, flexibility matrix and natural frequency and mode shapes are compared.

This paper deals with the design, development, modeling and experimental validation of a prototype endoscopic attachment that can be actuated independently by soft actuators to position an endoscopic catheter tip to a desired location. The soft actuators are miniaturized pneumatic artificial muscles (MPAMs) and by applying 137 kPa-827 kPa pressure to one or more MPAMs, the tip of the endoscopic catheter can be positioned in an approximately hemispherical region of 45 mm radius. An optimization-based forward kinematic model to predict the profile of the actuated end-effector is developed. Experiments conducted on the prototype show that the kinematics model can predict the deformation profile of the end-effector with a maximum error of 2 mm. An inverse kinematics model to estimate the pressure required in the MPAMs to position the tip of the catheter at a specified point is also developed. The pressures in the MPAMs are controlled using an ATmel ATMega 2560 micro-controller with the inputs generated with a thumb-stick to show that real-time actuation is possible. Finally, ex-vivo experiments were conducted to show that the developed prototype endeffector can be successfully used to independently actuate endoscopic catheters.

In this paper, we present the design, development, modeling, and experimental validation of an endoscopic attachment that can be used to independently position an endoscopic catheter tip at a desired location. Three miniaturized pneumatic artificial muscles (MPAMs) are used in a flexible endoscopic attachment, each MPAM is of 1.2 mm diameter and 45 mm in length and placed approximately 120 degrees apart within a pair of concentric springs. Pressurizing one or more MPAMs allows the tip to be positioned in a workspace, which is approximately a hemispherical section of radius 45 mm. We present a new and improved theoretical model for pressure-deformation relationship of a MPAM using static equations of a pressurized thick cylinder and constraints due to the braids. Comparison with existing models show that the proposed model performs better and the errors predicted by the model are less than 5% with experiments. A new forward kinematic model relating the position and orientation of the tip of the end-effector with changes in MPAM lengths is developed. Finally, we present experimental results conducted on a prototype endoscopic attachment and show that our model could predict the pose of the end-effector with a maximum error of 2 ± 1 mm.

A McKibben actuator/ Pneumatic artificial muscle(PAM) is a soft actuator which has great potential in the field of bio-inspired robotics. Miniaturized versions of PAMs or MPAMs of less than 1.5 mm diameter are ideal actuators for developing surgical devices due to their compliance and high power to weight ratio. Accurate mathematical models to represent the mechanics of PAM is an ongoing research. This paper develops a mathematical model which relates the input pressure to end-point deformation of a fabricated MPAM without external loading. The developed theoretical model is validated against experimental data for MPAM of lengths 60 mm and 70 mm. The model predicts the deformation of MPAM with standard error of less than 10%. The model is also able to predict the locking angle of 54.7 • at higher pressures which is a distinct characteristic of McKibben actuators.

The paper stands for a layered architecture approach of the sensor software component stack for the Internet of Things applications. A well-defined architecture is one of the key success factors for a project, as it improves the maintainability, reusability, and other things related to the efficiency in software development. The concept is inspired by the AUTomotive Open System ARchitecture (AUTOSAR) approach of the Software component Development with the proposal to extend the architecture with the Sensor and Actuator component stacks as parts of so named, here, Extended Software (ESW). The first part presents a generic architecture for an IoT device, following with a generic software component stack proposal, applied for any component from the proposed architecture, going through the description of all layers from the Service down to Hardware abstraction, with an implementation proposal, also covering the HW/SW association. In the end, an architecture example for environmental dat...

An aircraft fatigue test rig consists ofa number of vertically mounted hydraulic jacks which are connected to the underside of an aircraft and are used to apply to the aircraft a prescribed sinusoidal loading pattern. Each jack is fitted with a pressure-ratio valve which is used to amplify or attenuate the input pressure signal generated from a common source. Part 1 describes and discusses the first stage of an investigation into the factors affecting the performance of a single valve-jack system. The equations of motion are formulated and the values of the system parameters are obtained either by calculation or from the results of practical tests. In a number of cases, a comparison is made between the theoretical and practical values and, where appropriate, the results are discussed with reference to the work of earlier investigators. An analogue computer simulation of the system, which is discussed in Part 2, shows the mathematical model derived herein to be an accurate representation of the practical system.

The purpose of thesis is to show the result of the analysis Pneumatic Artificial Muscle (PAM). Thus, more information to understand on its behavior in generating force for actuation is obtained. The content of this report consists of few sections such as the introduction, literature review, methodology, result and discussion and conclusion. The introduction part consists of project background and problem statement that discuss PAM behavior while researching about this project. The introduction also discuss about the objective and scope of study which is to analyze the behavior of Pneumatic Muscle by using Finite Element Analysis on ANSYS software. The methodology and project planning is stated to show the flow of the thesis and also the Gantt chart provided shows the working schedule that I follow during all this period of year. The result and discussion shows that the construction of 3D PAM model is mainly consists of flexible, inflatable membrane for which the material type and pr...

Director configuration of a side-chain type 'monodomain' nematic elastomer with global director under temperature variation is investigated in a mechanically constrained geometry where the thermally induced macroscopic deformation is strictly prohibited. The corresponding elastomer in the unconstrained geometry exhibits a finite elongation along the director by cooling to a temperature in the nematic state from the isotropic state as a result of an increase in nematic order. The mechanical constraint, where the macroscopic dimensions in the nematic state are kept to be the same as those in the isotropic state, has a pronounced effect on director configuration: The constrained elastomer shows a 'polydomain' texture composed of randomly oriented local domains in the nematic state.

Trailing edge modification is one of the most effective ways to achieve camber variations. Usual flaps and aileron implement this concept and allow facing the different needs related to takeoff , landing, and maneuver operations. The extension of this idea to meet other necessities, less dramatic in terms of geometry change yet useful a lot to increase the aircraft performance, moves toward the so-called morphing architectures, a compact version of the formers and inserted within the frame of the smart structures' design philosophy. Mechanic (whether compliant or kinematic), actuation and sensor systems, together with all the other devices necessary for its proper working, are embedded into the body envelope. After the successful experiences, gained inside the SARISTU (SmARt Intelligent Aircraft STrUctures) project where an adaptive trailing edge was developed with the aim of compensating the weight variations in a mediumsize commercial aircraft (for instance, occurring during cruise), the team herein exploits the defined architecture in the wing of a typical airfoil, used on high-altitude long-endurance aircraft such as the Global Hawk. Among the peculiarities of this kind of aerial vehicle, there is the long endurance, in turn, associated with a massive fuel storage (approximately around 50% of the total weight). A segmented, finger-like, rib layout is considered to physically implement the transition from the baseline airfoil to the target configurations. This article deals with an extensive estimation of the possible benefits related to the implementation of this device on that class of planes. Parametric aerodynamic analyses are performed to evaluate the effects of different architectural layouts (in-plane geometry extension) and different shape envelopes (namely, the rotation boundaries). Finally, the expected improvements in the global high-altitude long-endurance aircraft performance are evaluated, following the implementation of the referred morphing device.

This article proposes a bending angle controller for soft pneumatic actuators, which could be implemented in soft robotic rehabilitation gloves to assist patients with hand impairment, such as stroke survivors. A data-driven model is used to estimate the angle as pneumatic pressure is applied to the actuator. Furthermore, a finite element model was used to manually optimize the dimensions of the actuator. An embedded flex sensor, which together with a custom testing rig, was used to gather input data for the data-driven model. This rig contains a pneumatic pressure control circuit as well as a camera for image acquisition. Collected data were fed into a linear regression model to predict the data-driven model. Experiments were carried out to validate model's accuracy as well as modified proportional-integral-derivative controller angle controller performance. The latter controller is designed to mitigate the non-linear response of solenoid valves at different pressures of the actuator. The data-driven model along with the used controller allows more accurate estimation and quicker response.

This paper presents an analysis of the strength of a prototype test rig for testing rotors of unmanned aerial vehicles. Digital design software was used for the design work that covered the creation of a virtual model of the test rig and strength analysis of its key elements. The paper discusses the test rig solutions, applied to date, of the small main rotor research. From the assumed operational parameters and structural parameters of the rotor, the main forces acting on the designed structure were determined: lifting force, reaction torque and empty mass of the test rig. Suitable actuators of the control system enabling the regulation of the total pitch and periodic pitch of the rotor, within the full range of the angle of attack, were selected for the rotor under test. The FEM (Finite Element Method) strength analysis was carried out for the proposed support structure and the correctness of the design was verified.