The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
We demonstrated a wireless vibration sensing system powered by a piezoelectric vibration energy harvester (VEH). The VEH with an AlN piezoelectric film was fabricated using a standard semiconductor micro electric mechanical system technology. Vibration with >0.45 m/s2 acceleration was applied to the VEH and a 40 bit payload was successfully sent using 920 MHz wireless communication technology driven...
Inertial sensors are used widely for detecting different contexts. However, noise components at high frequencies can disturb the recognition. In this paper, the measurements are made with multi IMU (MIMU) which combines the results of 32 inertial sensors. Averaging of individual sensor outputs reduce the noise level significantly and enables higher resolution. As an example case, we present application...
This paper presents the different stages of development of flight controller for unmanned aerial vehicle (UAV) with autonomously flying capability. The main purpose of flight controller is to perform a petrol function between given GPS coordinates while maintaining a specified altitude for an assigned time and then return to its launching position without any human interaction. At first a simulated...
A self-powered event-triggered wireless sensor network was developed for monitoring sabotage activities. The network has the capability of identifying suspicious activities and automatically sending out alarming signals. The sensor network consists of self-powered wireless alarming sensor nodes (SWASNs), router nodes, receiver nodes, GSM network and PC terminal. The SWASN is powered by a novel vibration-threshold...
Micromachined resonant sensors have been researched for several decades for a variety of applications with potential benefits in terms of improved sensitivity and scalability relative to other transduction principles. Conventional implementations usually involve detection elements monitoring resonant frequency and/or dissipation shift in a single degree-of-freedom or several independent degrees-of-freedom...
With the pace of construction of electrical grid, more districts are likely to be influenced by galloping of overhead transmission lines in winter. The galloping of overhead transmission lines may cause mechanical damages to metal fittings, insulators and transmission line towers. So it's of great significance to monitor the state and movement of overhead transmission lines. In transmission line galloping...
In the past decade there have been significant advancements in computer technology that have reduced the hardware form factor as well as increased energy efficient computing. Using network protocols for near field communication such as Body Area Networks (BANs), smaller and lighter computing units with attached sensors have transformed into wearable devices. These devices have served a plethora of...
A scheme combining phase-sensitive optical time domain reflectometry and Mach-Zehnder interferometer based on frequency division multiplexing has been demonstrated. The spatial resolution of 10m over 3Km sensing fiber and vibration frequency of 40 KHz are obtained.
We propose an algorithm which uses an optical time-domain reflectometer (OTDR) for real-time tracking of trains. OTDR sensing, often also termed distributed acoustical sensing (DAS), measures the Rayleigh backscattering of a light pulse along an optical fiber. The resulting signal provides information on local acoustic pressure at linearly spaced positions along the fiber. While different approaches...
In this paper a complete and inexpensive CNC milling chatter monitoring system is presented. By using a MEMS (Micro-Electro Mechanical System) accelerometer as a transducer mounted on the machine table, Arduino was used in a data acquisition platform and open source software to analyze the data in a completely functional chatter detection device. Initially the system was used to identify the main...
The vibrations while Milling often impact the results, sometimes generating very important cost because of the lack of quality for high value parts as well as cutting tool wear due to chatter phenomenon that happens during unstable vibrations. To mitigate this phenomenon, many techniques exist like passive and semi-active methods but the active control in milling, which is not as widespread in turning...
Seismic imaging is the primary technique for subsurface exploration. Traditional seismic imaging techniques rely heavily on manual labor to plant sensors, lay miles of cabling, and then recover the sensors. Often sites of resource or rescue interest may be difficult or hazardous to access. Thus, there is a substantial need for unmanned sensors that can be deployed by air and potentially in large numbers...
Automated Teller Machines (ATMs) security is the field of study that aims at solutions that provide multiple points of protection against physical and electronic theft from ATMs and protecting their installations. From anti-skimming defend systems to silent indicate systems, integrated ATM video surveillance cameras and ATM monitoring options, security specialists are ready to help the people get...
Bolted joints are widely used in CNC machine tools and the presence of joint interface results in discontinuities in the local stiffness and damping of the structure, which affects the dynamic characteristics of CNC machine tools. This paper focuses on identification techniques for the nonlinear characteristics of bolted joints from experimental perspectives: (1) Time-domain methods and frequency-domain...
Described in this paper is a mechatronic system whose functionality relies on the combination of fast, adaptive digital control and a carefully designed electromechanical system. Near-field acoustic levitation exploits elevated pressure due to the nonlinear pressure-volume characteristics of air. By controlling the actuator's vibration pattern of standing and traveling waves, a levitated object can...
This paper describes the basics of high-speed holographic metrology, its limitations, and its application to the investigation of traveling acoustic waves propagating in mechanical structures. Limits are related to few parameters that must be carefully adjusted for the recording. Applications to vibro-acoustics of structures consider the case of waves propagating after a shock and in an acoustic black...
There has been an increasing interest in sensing angular micro motion, ranging from personal tremor in the medical applications to sensitive vibration platform for surveillance in the defense applications. Sensing micro angular motion is a challenging task though because of the requirement of high accuracy. In addition, the motion is small which results in weak sensor signals. Hence, this paper proposes...
This paper presents a method for improved auscultation with an electronic stethoscope by estimating and removing the effects of unknown disturbance inputs. By replacing the single transducer in a stethoscope with a dual piezo transducer assembly, it is shown that an inverse dynamic mapping can be used to relate the two measured signals to original directional inputs acting on the stethoscope. Specifically,...
We present in this paper our development of a cyber physical sensing platform for monitoring the structural tension of large bridge cables using MEMS vibration sensors and proprietary wireless technology. In order to implement the online tension analysis of the bridge cables, we developed an improved technology for the general identification of cable tension using the Gauss-Newton method to determine...
There is a persistent problem that continues to be a relevant demand for the chemical, oil, food and pharmaceutical industries, the fouling detection in ducts systems. This work shows the early tests to develop a platform for detecting fouling in pipes and analyze specific locations using the impact hammer test based on a wireless sensor network communication. To minimize the costs of maintaining...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.