Current Issue : October - December Volume : 2016 Issue Number : 4 Articles : 6 Articles
A rotating actuator in the active mass damper system for structural vibration control is proposed in this article.\nDifferent from the linear actuator in the traditional active mass damper system, a rotating actuator is developed to suppress\nstructural vibration. With the introduction of rotational movement and external excitations, nonlinearity and\nuncertainty are considered in the system. Using the Lagrange equations, the mathematical model of the nonlinear\nstructureââ?¬â??active mass damper system with uncertainty is derived. Regarding the uncertainty in the model, a hierarchical\nsliding mode controller is designed based on Lyapunov stability theory. Numerical and experimental analyses are conducted\nto prove the effectiveness of the control algorithm and the reliability of the control device....
Over the last few decades, several advancements in the field of smart environment gained importance, so the experts can analyze\nideas for smart building based on embedded systems to minimize the expense and energy conservation.Therefore, propelling the\nconcept of smart home toward smart building, several challenges of power, communication, and sensors� connectivity can be seen.\nSuch challenges distort the interconnectivity between different technologies, such as Bluetooth and ZigBee, making it possible to\nprovide the continuous connectivity among different objects such as sensors, actuators, home appliances, and cell phones. Therefore,\nthis paper presents the concept of smart building based on embedded systems that enhance low power mobile sensors for sensing\ndiscrete events in embedded systems. The proposed scheme comprises system architecture that welcomes all the mobile sensors\nto communicate with each other using a single platform service.The proposed system enhances the concept of smart building in\nthree stages (i.e., visualization, data analysis, and application). For low powermobile sensors, we propose a communication model,\nwhich provides a common medium for communication. Finally, the results show that the proposed system architecture efficiently\nprocesses, analyzes, and integrates different datasets efficiently and triggers actions to provide safety measurements for the elderly,\npatients, and others....
The aim of this work was to develop an eddy current type pressure sensor and investigate\nits fundamental characteristics affected by the mechanical and electrical design parameters of sensor.\nThe sensor has two key components, i.e., diaphragm and coil. On the condition that the outer\ndiameter of sensor is 10 mm, two key parts should be designed so as to keep a good linearity and\nsensitivity. Experiments showed that aluminum is the best target material for eddy current detection.\nA round-grooved diaphragm is suggested in order to measure more precisely its deflection caused by\napplied pressures. The design parameters of a round-grooved diaphragm can be selected depending\non the measuring requirements. A developed pressure sensor with diaphragm of t = 0.2 mm and\nw = 1.05 mm was verified to measure pressure up to 10 MPa with very good linearity and errors of\nless than 0.16%....
Gas/liquid phase changes produce large volume changes in working fluids. These volume changes are used as the\ndriving power sources in actuators such as micro-pumps and valves. Most of these actuators are utilized in ordinary\ntemperature environments. However, the temperature range in which the phase change actuator can operate\ndepends on the characteristics of the working fluid. We hypothesized that proper selection of the working fluid and\nthe structure of the actuator can enable such actuators to be applied not only in ordinary environments but also in\nhigh temperature environments. Consequently, in this paper, we discuss the design and fabrication of a new gas/\nliquid phase change actuator for use in high temperature environments. Our proposed actuator consists of a bellow\nbody, spring, heater, and working fluid. We used the Inconel super alloy, which is highly heat and corrosion resistant,\nfor the bellow and moving parts of the actuator. For the working fluid, we prepared triethylene glycol, which has a\nboiling point of 287.3 �°C and very low vapor pressure at ordinary temperature. As a result, our proposed actuator can\nbe utilized in high temperature environments up to 300.0 �°C. The results of several experiments conducted confirm\nthat our proposed actuator generates 1.67 mm maximum displacement in a 300.0 �°C atmospheric environment. In\naddition, we confirmed that the operation of the actuator is stable in that environment. Our results confirm that a\ngas/liquid phase change actuator can be used in high temperature environments....
Wearable technologies are gaining momentum and widespread diffusion. Thanks to devices such as activity trackers, in form\nof bracelets, watches, or anklets, the end-users are becoming more and more aware of their daily activity routine, posture, and\ntraining and canmodify their motor-behavior. Activity trackers are prevalently based on inertial sensors such as accelerometers and\ngyroscopes. Loads we bear with us and the interface pressure they put on our body also affect posture. A contact interface pressure\nsensing wearable would be beneficial to complement inertial activity trackers.What is precluding force sensing resistors (FSR) to be\nthe next best seller wearable? In this paper, we provide elements to answer this question.We build an FSR based on resistivematerial\n(Velostat) and printed conductive ink electrodes on polyethylene terephthalate (PET) substrate; we test its response to pressure in\nthe range 0ââ?¬â??2.7 kPa. We present a state-of-the-art review, filtered by the need to identify technologies adequate for wearables. We\nconclude that the repeatability is the major issue yet unsolved....
In this paper, we propose a temperature/thermal sensor that contains a Rhodamine-B\nsensing membrane. We applied two different sensing methods, namely, fiber-optic pulse width\nmodulation (PWM) and an interdigitated capacitor (IDC)-based temperature sensor to measure\nthe temperature from 5 Ã?ÂC to 100 Ã?ÂC. To the best of our knowledge, the fiber-optic PWM-based\ntemperature sensor is reported for the first time in this study. The proposed fiber-optic PWM\ntemperature sensor has good sensing ability; its sensitivity is ~3.733 mV/Ã?ÂC. The designed\ntemperature-sensing system offers stable sensing responses over a wide dynamic range, good\nreproducibility properties with a relative standard deviation (RSD) of ~0.021, and the capacity\nfor a linear sensing response with a correlation coefficient of R2 ? 0.992 over a wide sensing range. In\nour study, we also developed an IDC temperature sensor that is based on the capacitance variation\nprinciple as the IDC sensing element is heated. We compared the performance of the proposed\ntemperature-sensing systems with different fiber-optic temperature sensors (which are based on\nthe fiber-optic wavelength shift method, the long grating fiber-optic Sagnac loop, and probe type\nfiber-optics) in terms of sensitivity, dynamic range, and linearity. We observed that the proposed\nsensing systems have better sensing performance than the above-mentioned sensing system....
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