Wireless Transducer Interface Module Research Articles

Wireless Sensor Network for Temperatures Estimation in an Asynchronous Machine Using a Kalman Filter

<p class="Abstract">A 4<sup>th</sup>-order Kalman filter (KF) algorithm is developed based on the thermal model of an asynchronous machine. The thermal parameters are identified and KF is implemented in a wireless sensor network (WSN) to estimate the temperatures of the stator windings, the rotor cage, and the stator core of an asynchronous machine. The rotor speed, coolant air temperature, and the effective current and voltage are acquired by a WTIM (wireless transducer interface module) separately and transmitted to a NCAP (network capable application processor) where the KF algorithm is implemented. Losses of the stator windings and the rotor cage are copper losses, and the stator core losses are iron losses. The losses of the stator windings, the rotor cage and the stator core are calculated from the measurements and are processed with the coolant air temperature by KF. As the resistance varies from temperature, the estimated temperature of the stator windings is used for compensating the rising of resistance. Simulations and experiments on the test bench were performed before the KF algorithm is implemented on a wireless sensor node. The real-time temperature estimator on WSN is independent of control algorithm and can work under any load condition with very high accuracy.</p>

A framework for wireless sensor networks management for precision viticulture and agriculture based on IEEE 1451 standard

Precision viticulture (PV) and precision agriculture (PA) requires the acquisition and processing of a vast collection of data coming typically from large scale and heterogeneous sensor networks. Unfortunately, sensor integration is far from being simple due to the number of incompatible network specifications and platforms. The adoption of a common, standard communication interface would allow the engineer to abstract the relation between the sensor and the network. This would reduce the development efforts and emerge as an important step towards the adoption of “plug-and-play” technology in PA/PV sensor networks. This paper explores this need and introduces a framework for smart data acquisition in PA/PV that relies on the IEEE 1451 family of standards, which addresses the transducer-to-network interoperability issues. The framework includes a ZigBee end device (sMPWiNodeZ), as an IEEE 1451 WTIM (Wireless Transducer Interface Module), and an IEEE 1451 NCAP (Network Capable Application Processor) that acts as gateway to an information service provider and WSN (Wireless Sensor Network) coordinator. The paper discusses the proposed IEEE 1451 system architecture and its benefits in PA/PV and closes with results/lessons learned from in-field trials towards smarter WSN.

PAMC Based IEEE 1451 Wireless Sensor Interface Plug And Play Mechanism and Implementation

Aims at ZigBee wireless intelligent sensor that complies with IEEE 1451.5, an implementation method based on periodic association matching communication (PAMC) is put forward in order to realize wireless sensor interface plug and play. Four kinds of communication message frame format are defined at ZigBee application support sublayer, and the contents of transducer electronic data sheet (TEDS) are redefined according to actual application. Both network capable application processor (NCAP) and wireless transducer interface module (WTIM) start protocol stack event handling process to monitoring network structure change, and data storage units are used to realtime update, save the network structure parameters. An association configuration table is defined in NCAP to preserve WTIM transducer channel information. Through the association request frames periodically send by WTIM, NCAP can quickly and accurately identify WTIM access, disconnect network. Set up a ZigBee intelligent sensor system test platform, test show that using PAMC method can effectively implement IEEE 1541 wireless sensor interface plug and play and identification; Set association matching communication period to 1 second, WTIM network access time is less than 1.8seconds, better meets the practical application requirements.

IEEE 1451 Standard in 6LoWPAN Sensor Networks Using a Compact Physical-Layer Transducer Electronic Datasheet

The adoption of the Internet Protocol version 6 (IPv6) networking in IEEE 802.15.4 sensor networks, using IEEE 1451 standardization, increases the interoperability of low-power smart-sensor devices over IP networks. This paper explains the design and implementation of the IPv6 sensor network over low-power wireless personal-area networks (6LoWPANs), and it uses the IEEE 1451 standard in IEEE 802.15.4 sensor networks. We propose the design of the 6LoWPAN physical-layer transducer electronic datasheet (PHY-TEDS) using data-type redefinition with the header compression. Each TEDS was analyzed in terms of memory size, obtaining a reduction of 48% in the PHY-TEDS and 25% in the meta-TEDS with respect to the standard definition. Finally, the IEEE 1451 commands are encapsulated in User Datagram Protocol datagrams to establish communication from the network capable application processor to the wireless transducer interface module in an environmental monitoring application.