Thermoelectric energy harvester with a cold start of 0.6 °C

This paper presents the electrical and thermal design of a thermoelectric energy harvester power system and its characterisation. The energy harvester is powered by a single Thermoelectric Generator (TEG) of 449 couples connected via a power conditioning circuit to an embedded processor. The aim of the work presented in this paper is to experimentally confirm the lowest ΔT measured across the TEG (ΔTTEG) at which the embedded processor operates to allow for wireless communication. The results show that when a temperature difference of 0.6 °CΔTTEG is applied across the thermoelectric module, an input voltage of 23 mV is generated which is sufficient to activate the energy harvester in approximately 3 minutes. An experimental setup able to accurately maintain and measure very low temperatures is described and the electrical power generated by the TEG at these temperatures is also described. It was found that the energy harvester power system can deliver up to 30 mA of current at 2.2 V in 3ms pulses for over a second. This is sufficient for wireless broadcast, communication and powering of other sensor devices. The successful operation of the wireless harvester at such low temperature gradients offers many new application areas for the system, including those powered by environmental sources and body heat

Wireless sensors and IoT platform for intelligent HVAC control

Energy consumption of buildings (residential and non-residential) represents approximately 40% of total world electricity consumption, with half of this energy consumed by HVAC systems. Model-Based Predictive Control (MBPC) is perhaps the technique most often proposed for HVAC control, since it offers an enormous potential for energy savings. Despite the large number of papers on this topic during the last few years, there are only a few reported applications of the use of MBPC for existing buildings, under normal occupancy conditions and, to the best of our knowledge, no commercial solution yet. A marketable solution has been recently presented by the authors, coined the IMBPC HVAC system. This paper describes the design, prototyping and validation of two components of this integrated system, the Self-Powered Wireless Sensors and the IOT platform developed. Results for the use of IMBPC in a real building under normal occupation demonstrate savings in the electricity bill while maintaining thermal comfort during the whole occupation schedule.QREN SIDT [38798]; Portuguese Foundation for Science & Technology, through IDMEC, under LAETA [ID/EMS/50022/2013

A Wireless Sensor Network for Cold-Chain Monitoring

This paper deals with a wireless sensor network that was specifically designed to monitor temperature-sensitive products during their distribution with the aim of conforming to the cold-chain assurance requirements. The measurement problems and the constraints that have been encountered in this application are initially highlighted, and then, an architecture that takes such problems into account is proposed. The proposed architecture is based on specifically designed measuring nodes that are inserted into the products to identify their behavior under real operating conditions, e.g., during a typical distribution. Such product nodes communicate through a wireless channel with a base station, which collects and processes the data sent by all the nodes. A peculiarity of the product nodes is the low cost, which allows the information on the cold-chain integrity to be provided to the final customer. The results that refer to the functional tests of the proposed system and to the experimental tests performed on a refrigerated vehicle during a distribution are reporte

Design and Manufacture of Wireless Monitoring system of Photovoltaic Generation Employing Raspberry PI 3

This paper recounts design and development the realtime and wireless monitoring systems to observed the characteristics and performanced of the solar photovoltaic (pv) energy generation. The monitoring systems designed used the Raspberry Pi 3 as the data processing center, the voltage divider as the voltage sensor, ACS712 as the current sensor, DHT as the temperature sensor, and BH1750 as the solar irradiation sensor. The measurements of the pv generation characteristics are carried out all the time in real time. The monitoring systems developed has calibrated with standard measuring instruments. The measurement data has processed, sent and stored in the database via the internet. The MySQL database with single user interface using the Web-based programming language has employed. This research has proven that the system designed to functioning properly and correctly to achieve the objectived. The novelty of these project are the pv wireless monitoring systems techniques with the simple device resources, capable of showing maximum performanced

Root Zone Sensors for Irrigation Management in Intensive Agriculture

Crop irrigation uses more than 70% of the world’s water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the grower’s experience or on the determination of soil water balance (weather-based method). An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS), such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZS’ (for both soil moisture and salinity) marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy) on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy

Bridges Structural Health Monitoring and Deterioration Detection Synthesis of Knowledge and Technology

INE/AUTC 10.0

Fly, Wake-up, Find: UAV-based Energy-efficient Localization for Distributed Sensor Nodes

A challenging application scenario in the field of industrial Unmanned Aerial Vehicles (UAVs) is the capability of a robot to find and query smart sensor nodes deployed at arbitrary locations in the mission area. This work explores the combination of different communication technologies, namely, Ultra-Wideband (UWB) and Wake-Up Radio (WUR), with a UAV that acts as a "ubiquitous local-host"of a Wireless Sensor Network (WSN). First, the UAV performs the localization of the sensor node via multiple UWB range measurements, and then it flies in its proximity to perform energy-efficient data acquisition. We propose an energy-efficient and accurate localization algorithm - based on multi-lateration - that is computationally inexpensive and robust to in-field noise. Aiming at minimizing the sensor node energy consumption, we also present a communication protocol that leverages WUR technology to minimize ON-time of the power-hungry UWB transceiver on the sensors. In-field experimental evaluation demonstrates that our approach achieves a sub-meter localization precision of the sensor nodes - i.e., down to 0.6 m - using only three range measurements, and runs in 4 ms on a low power microcontroller (ARM Cortex-M4F). Due to the presence of the WUR and the proposed lightweight algorithm, the entire localization-acquisition cycle requires only 31 mJ on the sensor node. The approach is suitable for several emerging Industrial Internet of Things application scenarios where a mobile vehicle needs to estimate the location of static objects without any precise knowledge of their position