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Wireless Sensor Network (WSN) is an emerging technology which has been employed recently in various applications such as healthcare systems, environmental monitoring, military and industrial applications. This is due to the easy deployment and (re)configuration of the sensor nodes in the environment. It also has the potential of being integrated into the distributed manufacturing systems particularly...
Wireless Sensor and Actuator Networks has become an important area of research. They can provide flexibility, low operational and maintenance costs and they are inherently scalable. In the realm of Internet of Things the majority of devices is able to communicate with one another, and in some cases they can be deployed with an IP address. This feature is undoubtedly very beneficial in wireless sensor...
Fault Tolerant Controls are highly reliable control systems aimed at increasing system reliability and reducing safety hazards. FTCs are designed to accommodate faults at their early stage of development to prevent those minor faults from developing into failures that might jeopardize system stability and availability. FTC design is a topic of active and ongoing research activities with applications...
In this article, we describe the analysis of a composite piezoelectric actuator intended for a force feedback application. The concept of the force feedback interface is based on reduction of the friction coefficient between two surfaces in contact, and the aim here is to achieve an enhanced performance design based on the existing actuator. For this purpose, and following up a previous study, the...
The stick-slip actuator motion is dependent on its natural frequency. The backward motion of the actuator during the slip phase due to the stiffness alters the motion of any stickslip friction principle based positioners drastically. This work is an attempt to design and fabricate a simple and compact piezoelectric walker integrated with a force sensor to measure the frictional force during the slip...
This article proposes a time efficient set-point tracking controller. The proposed controller synthesizes smooth control input within the input saturation limits of a class of second order nonlinear continuous time plants. The Lyapunov function based analysis assures the global asymptotic stability of the closed-loop and the convergence of the set-point tracking error to zero. The computer simulation...
The incorporation of an equivalent-input-disturbance estimator into a conventional sliding-mode control (SMC) system results in a new structure with improved disturbance rejection performance. This configuration enables an SMC system to reject unmatched disturbances. Simulation results for the positioning control of a dual-stage feed drive show that the method not only rejects unmatched disturbances,...
In this paper, a new combined approach for fault detection and diagnosis (FDD) of abrupt additive actuator and sensor faults, based on Kalman observer (KFO), on sliding mode observers (SMO), on singular values decomposition (SVD), and on principal component analysis (PCA), is proposed. The main contribution is the combined approach proposed for FDD based on ratios between singular values of the adaptive...
It is well-known that, one of the main disadvantages of parallel manipulators is their abundant singularities that diminish the usable workspace and limit their applications for machine tools. To overcome this problem, a 3-PPR planar parallel one in a non-conventional architecture is developed in this paper for a hybrid machine tool. The proposed architecture is shown to have some kinematic advantages...
Without fault-tolerance, a single component failure in a Networked Control System (NCS) can cause system downtime and potentially large production losses. Thus, fault-tolerance is fast becoming a key aspect in the design and evaluation of NCS architectures. In this paper, the focus is on the reliability modeling of network fabric level fault-tolerant NCSs. The two main considered fault-tolerant architectures...
Smart and energy efficient (office) buildings do not only have to implement smart sensors and actuators, they should also be able to be optimized to be as energy efficient as possible based on the behavior of the user. This paper focuses on knowledge extraction of a smart building and automatic rule creation based on that knowledge. We are using different methods to analyze this data, create the appropriate...
The introduction of a new product in the aeronautical sector implies conducting characterization tests in an automated, safe and sustainable way. This paper describes a dedicated test bench design and validation that allows characterizing a swashplate Helicopter Electro Mechanical Actuation System (HEMAS). The test bench replicates the operating conditions that the actuator will encounter in service...
The objective of this study is to propose the master-slave tendon-driven haptic robot hand system using Twist Drive. Twist Drive is one of transmission systems which is consisted of a pair of strings and rotary motor. This transmission system converts torque into a high pulling force by using a pair of strings twisted on each other. In this paper, Twist Drive system is verified at first. Next, Twist...
Low range differential air pressure sensors are used widely in various applications. In this paper the effects of temperature change on transient behavior of the calibration setup for differential air pressure sensors, due to temperature gradient are analyzed. A high performance reference setup utilizing ideal gas law, for differential air pressure sensors, is selected for experimental analysis. The...
The design of a wave energy converter (WEC) requires the preliminary selection of dimensional parameters in accordance with variables such as location site, power take off (PTO) characteristics or control strategy, with the aim of developing a realistic model to be used in the test of power takeoff devices. The paper proposes a laboratory test bench to test direct-drive linear generators, for being...
This paper details the design and development of a hybrid actuator system combining surface actuated Shape memory alloys (SMAs) and trailing-edge Macro fibre composites (MFCs) for a NACA 4412 airfoil. This design allows both for a high-frequent (≈ 100 Hz) low-displacement actuation as well as a low-frequent large-displacement actuation. The design of the actuator system is highlighted, the simulation...
This paper proposes a novel architecture for a hierarchical Wireless Networked Control System (WNCS). It consists of three cascaded workcells each containing 30 sensors, 30 actuators and one controller. The wireless communication protocol used is IEEE 802.11g with multicasting. The hierarchy of the system is such that the lowest level is that of the sensors and actuators, the intermediate level is...
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