Bidirectional 868/915 MHz wireless module powered with energy harverster

In this paper, we present a work that allows bidirectional communications in the 868/915 MHz ISM bands, using the power generated by energy harvesters. Our investigations show that a clear channel assessment, receive of acknowledge and resend of the message are possible within a limited, but reasonable time. The design relies on the use of low power microcontrollers and transceivers, and low energy management techniques

Rapid Recovery of Program Execution Under Power Failures for Embedded Systems with NVM

After power is switched on, recovering the interrupted program from the initial state can cause negative impact. Some programs are even unrecoverable. To rapid recovery of program execution under power failures, the execution states of checkpoints are backed up by NVM under power failures for embedded systems with NVM. However, frequent checkpoints will shorten the lifetime of the NVM and incur significant write overhead. In this paper, the technique of checkpoint setting triggered by function calls is proposed to reduce the write on NVM. The evaluation results show an average of 99.8% and 80.5$% reduction on NVM backup size for stack backup, compared to the log-based method and step-based method. In order to better achieve this, we also propose pseudo-function calls to increase backup points to reduce recovery costs, and exponential incremental call-based backup methods to reduce backup costs in the loop. To further avoid the content on NVM is cluttered and out of NVM, a method to clean the contents on the NVM that are useless for restoration is proposed. Based on aforementioned problems and techniques, the recovery technology is proposed, and the case is used to analyze how to recover rapidly under different power failures.Comment: This paper has been accepted for publication to Microprocessors and Microsystems in March 15, 202

A Heterogeneous Wireless Identification Network for the Localization of Animals Based on Stochastic Movements

The improvement in the transmission range in wireless applications without the use of batteries remains a significant challenge in identification applications. In this paper, we describe a heterogeneous wireless identification network mostly powered by kinetic energy, which allows the localization of animals in open environments. The system relies on radio communications and a global positioning system. It is made up of primary and secondary nodes. Secondary nodes are kinetic-powered and take advantage of animal movements to activate the node and transmit a specific identifier, reducing the number of batteries of the system. Primary nodes are battery-powered and gather secondary-node transmitted information to provide it, along with position and time data, to a final base station in charge of the animal monitoring. The system allows tracking based on contextual information obtained from statistical data

Analysis, Design and implementation of Energy Harvesting Systems for Wireless Sensor Nodes.

Ph.DDOCTOR OF PHILOSOPH

Cattle-powered nodes experience in a heterogeneous network for localization of herds

A heterogeneous network, mainly based on nodes that use harvested energy to self-energize is presented and its use demonstrated. The network, mostly kinetically powered, has been used for the localization of herds in grazing areas under extreme climate conditions. The network consists of secondary and primary nodes. The former, powered by a kinetic generator, take advantage of animal movements to broadcast a unique identifier. The latter are battery-powered and gather secondarynode transmitted information to provide it, along with position and time data, to a final base station in charge of the animal monitoring. Because a limited human interaction is desirable, the aim of this network is to reduce the battery count of the system

Greenmission: An off-grid energy system

In alignment with Santa Clara University\u27s sustainability ideology, the outdoor science school WaldenWest desired to further its students\u27 education through a greenhouse with working electricity. Following greenhouse purchase and assembly, underground wiring for AC, DC and Ethernet lines were sized and installed. A substation was then designed and built in a designated shed, integrating wind turbines and photovoltaics rom past capstone projects. New charge controllers, batteries and circuit breakers were urchased and configured for the system. Worst-case electrical load and solar shading analyses also revealed that these older energy sources were collectively inadequate, so a secondary solar array was designed and flush-mounted to the shed roof; the system falls lightly short of desired year-round performance, but is otherwise a drastic improvement. Electrical measurements show that power is received at the greenhouse with a less than 3% voltage drop, meeting national Electric Code standards. To maintain the greenhouse environment, substation loads are specifically selected to allow for temperature control. These are driven by the Supervisory Control And Data Acquisition (SCADA) system, which never leaves the greenhouse; an enclosed Raspberry Pi automates load operation through SainSmart relays and simple comparative logic. To account for both varying seasonal weather conditions and client accessibility, a Graphical User Interface (GUI) is programmed to allow adjustment of all relevant control parameters via Wi-Fi in real-time. A battery monitor from a past capstone project is also reconfigured to run on Linux to estimate remaining stored energy. Project analyses include ethical, aesthetics, commercial benefit and basic photovoltaic rate-of-return analyses. Hypothetical scenarios are frequently presented to investigate the potential consequences of client and residentially-replicated usage of the entire system. It is also estimated that the combined photovoltaics will result in a lifetime net zero energy in 4.3 years of continuous expected use. Future project work involves tasks that could not be accomplished within the project time frame and budget. Among these include a larger solar array; the 24VDC integration of the horizontal wind turbine; rigorous seasonally-based testing of temperature controlling mechanisms for better parameter adjustments; and finally, the propagation of electrical power beyond the immediate premises and into the entire Walden West garden. Based on client needs, inspiration for future project work will likely draw from the tremendous success of the Milwaukee, Wisconsin non-profit organization, Growing Power

Design of a Health Monitoring Device

Home medical monitoring systems allow care providers to reduce their patient load, but no available systems offer portable operation. This effectively tethers patients to a specific location. In conjunction with the University of Limerick, our team desiged and implemented a proof-of-concept portable medical monitor able to transfer medical data wirelessly. Our completed project supports USB and 802.11b, includes a display and basic user interface, and runs Linux, making it a highly flexible platform for future progression toward marketability

Development of a domestic or business security system for low volume, highly customizable production

Aquest treball pretén cobrir alguns dels passos involucrats en la creació d’una start-up especialitzada en el disseny, producció i comercialització de sistemes de seguretat modulars destinats a particulars i PIMEs. Es dóna èmfasi, principalment, en els aspectes tècnics del desenvolupament d’un prototip funcional. El prototip esmentat consisteix en un sistema de seguretat relativament senzill però que ofereix, apart de les funcions típiques dels sistemes de seguretat, una base per incorporar-hi noves funcions que el client especifiqui (sempre i quan siguin tecnològicament viables). És per això que es considera un sistema de seguretat personalitzable. El model de disseny d’aquest prototip bàsic és el d’una xarxa centralitzada de nodes independents. Cada node és un sensor o actuador que es connecta al node central, que és qui determina quines accions es realitzen en funció de la informació enviada pels sensors i la configuració introduïda per l’usuari. Un node és, essencialment, un dispositiu electrònic encapsulat en una carcassa, que realitza una funció determinada i es comunica sense fils. La xarxa és modular i pot acomodar qualsevol nou node que l’usuari vulgui incorporar. Per al desenvolupament d’un prototip es fa ús de la plataforma de desenvolupament Arduino i d’un nombre elevat de components electrònics fàcilment adquiribles en volums petits. També s’utilitzen eines típiques d’una caixa d’eines i una impressora 3D. En el disseny hi intervenen suites de software tals com KiCad, Solidworks, Repetier Host, Slic3r o Autocad. És un objectiu primordial del projecte investigar i aprendre suficient sobre aquestes tècniques per desenvolupar la idea. El treball es desenvolupa centrant-se primer en les funcions primordials d’un sistema de seguretat i deixant pel final les més supèrflues. En la memòria s’hi pot trobar una progressió d’apartats que dediquen una explicació a cada detall del desenvolupament. El llenguatge utilitzat és pragmàtic - atén les raons pràctiques d’enginyeria abans que les ciències de fons -, i pretén ser llegit com un treball de referència per projectes similars. El resultat tangible creat és un sistema de seguretat format per cinc nodes diferents: un node central, un node per introduir codis de desactivació (manualment o amb un clauer amb tecnologia RFID), un sensor de moviment, un sensor d’obertura de portes i finestres, i una brunzidor per quan es dispara l’alarma. Tots ells són prototipus muntats en protoboards. El sistema és totalment funcional i està governat per 2.900 línies de codi C++ sense incloure llibreries externes. El brunzidor, a més, també s’ha redissenyat en la seva versió Beta, amb el circuit electrònic soldat i inserit en una carcassa impresa en 3D. Amb tot, aquest projecte ha estat una gran font de coneixements relacionats amb electrònica, C++, embedded development, soldadura amb estany, disseny CAD, impressió 3D i supply chain

Upgrade Design for Septage Treatment: Pease Tradeport Wastewater Treatment Plant, Portsmouth, New Hampshire

This Major Qualifying Project was completed in conjunction with Stantec to design upgrade options to increase septage treatment capacity at the Pease Wastewater Treatment Plant in Portsmouth, NH. Designs modernized existing technologies and suggested methods to treat glycol waste. Following a site visit, data analysis, design alternative development, and cost estimates, designs were scored in health and safety, environmental and sustainability, economic, and constructability criteria. This project proposes one short-term and one long-term design to resolve existing and future problems