Software-Defined Lighting.

For much of the past century, indoor lighting has been based on incandescent or gas-discharge technology. But, with LED lighting experiencing a 20x/decade increase in flux density, 10x/decade decrease in cost, and linear improvements in luminous efficiency, solid-state lighting is finally cost-competitive with the status quo. As a result, LED lighting is projected to reach over 70% market penetration by 2030. This dissertation claims that solid-state lighting’s real potential has been barely explored, that now is the time to explore it, and that new lighting platforms and applications can drive lighting far beyond its roots as an illumination technology. Scaling laws make solid-state lighting competitive with conventional lighting, but two key features make solid-state lighting an enabler for many new applications: the high switching speeds possible using LEDs and the color palettes realizable with Red-Green-Blue-White (RGBW) multi-chip assemblies. For this dissertation, we have explored the post-illumination potential of LED lighting in applications as diverse as visible light communications, indoor positioning, smart dust time synchronization, and embedded device configuration, with an eventual eye toward supporting all of them using a shared lighting infrastructure under a unified system architecture that provides software-control over lighting. To explore the space of software-defined lighting (SDL), we design a compact, flexible, and networked SDL platform to allow researchers to rapidly test new ideas. Using this platform, we demonstrate the viability of several applications, including multi-luminaire synchronized communication to a photodiode receiver, communication to mobile phone cameras, and indoor positioning using unmodified mobile phones. We show that all these applications and many other potential applications can be simultaneously supported by a single lighting infrastructure under software control.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111482/1/samkuo_1.pd

Gesture Based Home Automation for the Physically Disabled

Paralysis and motor-impairments can greatly reduce the autonomy and quality of life of a patient while presenting a major recurring cost in home-healthcare. Augmented with a non-invasive wearable sensor system and home-automation equipment, the patient can regain a level of autonomy at a fraction of the cost of home nurses. A system which utilizes sensor fusion, low-power digital components, and smartphone cellular capabilities can extend the usefulness of such a system to allow greater adaptivity for patients with various needs. This thesis develops such a system as a Bluetooth enabled glove device which communicates with a remote web server to control smart-devices within the home. The power consumption of the system is considered as a major component to allow the system to operate while requiring little maintenance, allowing for greater patient autonomy. The system is evaluated in terms of power consumption and accuracy to prove its viability as a home accessibility tool

A Review of Low-end, Middle-end and High-end IoT Devices

Internet of Things (IoT) devices play a crucial role in the overall development of IoT in providing countless applications in various areas. Due to the increasing interest and rapid technological growth of sensor technology, which have certainly revolutionized the way we live today, a need to provide a detailed analysis of the embedded platforms and boards is consequential. This paper presents a comprehensive survey of the recent and most-widely used commercial and research embedded systems and boards in different classification emphasizing their key attributes including processing and memory capabilities, security features, connectivity and communication interfaces, size, cost and appearance, operating system (OS) support, power specifications and battery life and listing some interesting projects for each device. Through this exploration and discussion, readers can have an overall understanding on this area and foster more subsequent studies

Design Experiences on Single and Multi Radio Systems in Wireless Embedded Platforms

The progress of radio technology has made several flavors of radio available on the market.Wireless sensor network platform designers have used these radios to build a variety of platforms. Withnew applications and different types of radios on wireless sensing nodes, it is often hard to interconnectdifferent types of networks. Hence, often additional radios have to be integrated onto existingplatforms or new platforms have to be built. Additionally, the energy consumption of these nodes have to be optimized to meetlifetime requirements of years without recharging.In this thesis, we address two issues of single and multi radio platform designfor wireless sensor network applications - engineering issues and energy optimization.We present a set of guiding principles from our design experiences while building 3 real life applications,namely asset tracking, burglar tracking and finally in-situ psychophysiological stress monitoring of human subjects in behavioral studies.In the asset tracking application, we present our design of a tag node that can be hidden inside valuable personal assets such asprinters or sofas in a home. If these items are stolen, a city wide anchor node infrastructure networkwould track them throughout the city. We also present our design for the anchor node.In the burglar tracking application, we present the design of tag nodes and the issueswe faced while integrating it with a GSM radio. Finally, we discuss our experiencesin designing a bridge node, that connects body worn physiological sensorsto a Bluetooth enabled mobile smartphone. We present the software framework that acts as middleware toconnect to the bridge, parse the sensor data, and send it to higher layers of the softwareframework.We describe 2 energy optimization schemes that are used in the Asset Tracking and the Burglar Tracking applications, that enhance the lifetime of the individual applications manifold.In the asset tracking application,we design a grouping scheme that helps increase reliability of detection of the tag nodes at theanchor nodes while reducing the energy consumption of the group of tag nodes travelling together.We achieve an increase of 5 times improvement in lifetime of the entire group. In the Burglar Tracking application, weuse sensing to determine when to turn the GSM radio on and transmit data by differentiatingturns and lane changes. This helps us reduce the number of times the GSM radio is woken up, thereby increasing thelifetime of the tag node while it is being tracked. This adds 8 minutes of trackablelifetime to the burglar tracking tag node. We conclude this thesis by observing the futuretrends of platform design and radio evolution

Wake-up communication system using solar panel and visible light communication

[ANGLÈS] One of the most promising energy-efficient communication methods is the use of wake-up receivers. In this work we propose and develop a wake-up communication system that uses Visible Light Communication (VLC) and an indoor solar panel with two functions: act as the receiver of the wake-up signal and harvest power from the light. After the reception of the wake-up signal an interrupt generated by the wake-up receiver wakes up the wireless device attached. Two configuration options are presented: an addressable and a broadcast-based wake-up configuration. In addressable configuration, after the reception of the wake-up signal a comparison is made with the identification code configured in the device; as consequence only the device with the match code is woken up. In broadcast-based wake-up configuration the wireless node attached wakes up after the detection of the carrier burst frequency, allowing use this system for wake up several nodes at once. Two options of configuration for the receiver are presented, and also the design of a transmitter who copes with flickering mitigation. Through experiments the feasibility of the system is shown and its performances is characterized in terms of wake-up probabilities for different distances. The effect of light interferences is evaluated, which shows that the achieved wake-up distances are reasonable for indoor scenarios.[CASTELLÀ] Uno de los más prometedores métodos para la comunicación con mayor eficiencia energética en las Redes de Sensores Inalámbricos (Wireless Sensor Networks - WSN) es el uso de wake-up receivers. Es este trabajo se propone y desarrolla un sistema de comunicación de wake-up que usa las comunicaciones por luz visible (Visible Light Communication - VLC) y un panel solar de interiores con dos funciones: actuar como receptor de la señal de wake-up y recoger energía de la luz. Después de la recepción de la señal el wake-up receiver genera una interrupción activando el nodo inalámbrico adjunto. Se presentan dos configuraciones para la generación de la interrupción: una basada en dirección y otra basada en la transmisión de la frecuencia portadora. En la configuración basada en dirección, después de la recepción de la señal de wake-up se hace una comparación con el código de identificación configurado en el dispositivo; como consecuencia sólo el dispositivo con el código correcto es activado. En la configuración basada en la transmisión de la frecuencia portadora, el nodo inalámbrico adjunto se activa con la detección de dicha frecuencia, lo cual permite usar el sistema para activar varios nodos a la vez. Se describen dos opciones de configuración para el receptor, así como el diseño de un transmisor diseñado para mitigar el parpadeo del LED. A través de experimentos se muestra la factibilidad del sistema y se caracteriza su desempeño en términos de la probabilidad de generar la interrupción de activación a diferentes distancias entre la fuente de luz y el receptor. Se evalúa el efecto de las interferencias de luz y se muestra que las distancias alcanzadas son razonables para escenarios intramuros.[CATALÀ] Un dels mètodes més prometedors per a la comunicació amb una major eficiència energètica en les Xarxes de Sensors Sense fil (Wireless Sensor Networks - WSN) és l'ús de wake-up receivers en el node receptor. Els wake-up receivers són dispositius d'ultra-baix consum de potència connectats al node sense fil que li permeten romandre en estat inactiu mentre esperen un senyal d'activació. En aquest treball es proposa i desenvolupa un sistema d’activació que usa les comunicacions per llum visible (Visible Light Communication - VLC) i un panell solar d’ús interior amb dues funcions: actuar com a receptor del senyal d’activació i recollir energia de la llum ambient. Després de la recepció del senyal de l’emissor, el wake-up receiver genera una interrupció activant el node sense fil adjunt. Es descriuen dues alternatives per a la generació de la interrupció: una basada en identificador i una altra basada en la transmissió de la freqüència portadora. En la configuració basada en identificador, després de la recepció del senyal de wake-up es fa una comparació amb el codi d'identificació al dispositiu i, com a conseqüència, només el dispositiu amb el codi correcte és activat. En la configuració basada en la transmissió de la freqüència portadora, el node sense fil adjunt s'activa amb la detecció d'aquesta freqüència, la qual cosa permet utilitzar el sistema per activar diversos nodes alhora. També se detallen dues opcions de configuració per al receptor així com el disseny d'un transmissor per mitigar el parpelleig del LED. Mitjançant experiments es mostra la factibilitat del sistema i s’avalua el seu funcionament en termes de la probabilitat de generar la interrupció d'activació a diferents distàncies entre la font de llum i el receptor. S'avalua l'efecte de les interferències del senyal i es mostra que les distàncies assolides són raonables per escenaris en interiors

Bluetooth Low Energy data transfer in energy harvester system : Comparison of platforms and boards

Energy harvesting is a widely known concept when used on a larger scale such as solar panels, wind turbines, and hydro plants, but tiny-scale energy harvesters are less utilized. Energy harvesters are applied to tiny-scale devices to build an autonomous system, to get longer operation time than devices powered by batteries, and to enable new applications. Bluetooth is also an extensively used technology in consumer products as it is found in the majority of mobile devices. In contrast, Bluetooth Low Energy (BLE) is a new technology and more challenging to familiarize with. The thesis will present the reasons to use energy harvesting and BLE. Another essential topic is examining development environments for BLE microcontroller boards and combining boards in a system containing an energy harvester and a sensor. The system is located in an isolated area that is difficult to reach and must have an energy source available for the energy harvester. Finally, the thesis explains the steps for software development. A prototype was built in a research group and this thesis examines research knowledge and technologies related to the prototype. The prototype system includes an electromagnetic induction-based energy harvester. As the energy harvester is one of the main parts of the thesis, it requires further examination. Other project members tested and constructed the energy harvester, and this thesis includes a cursory overview of its use and operation. The implementation phase of the thesis focuses on developing software for BLE devices. After studying BLE theory, the next step is comparing and testing development environments and boards using data transferring programs. Ampiq Apollo3 SDK, Mbed Studio, and Arduino IDE are compared with SparkFun Artemis and Arduino BLE boards. The intended prototype testing environment will be the inner circle of a car tire, influencing the choice of the optimal BLE board which limits the case size and install area of the prototype. As a result, a program developed in the Mbed Studio could not make a BLE connection, setting the comparison to a new perspective, focusing more on theory rather than development. The unexpected outcome showed that extensive background research does not ensure functionality. The unsuccessful result did not prevent continuing development with other environments. Implications and ideas regarding future work are documented for the next developer. The other two environments were functional and allowed a meaningful comparison. The differences between boards are most significant when use cases and development environment are taken into account. For example, boards differ by size, shape, and energy consumption. The Bluetooth features are similarly available on all boards, but taking advantage of them varies by board. The thesis concludes with a discussion about future progression paths in energy harvesting and Bluetooth Low Energy applications.Energian harvesterointi on laajasti tunnettu käsite, kun sitä käytetään isommassa mittakaavassa kuten aurinkopaneelit, tuuliturbiinit ja vesivoimalat mutta pienen mittakaavan energia harvesterit ovat vähemmän hyödynnettyjä. Energia harvesteria käytetään pienen mittakaavan laitteissa, jotta saadaan itsenäinen systeemi, pidempi toiminta aika kuin paristoilla toimivilla laitteilla ja mahdollistaa uusia sovelluksia. Bluetooth on myös laajasti tiedetty teknologia kuluttajalaitteista kuten suurimmassa osassa mobiililaitteista löytyy Bluetooth. Kun taas Bluetooth Low Energy (BLE) on uusi teknologia ja haastavampi perehtyä. Tutkielmassa esitellään syyt käyttää energian harvesterointi ja BLE teknologioita. Toinen tärkeä aihe, jota käydään läpi tutkielmassa, on kehitys ympäristöt Bluetooth Low Energy mikrokontrolleri laudoille ja lautojen yhdistäminen systeemiin, joka sisältää energia harvesterin ja sensorin. Systeemi on sijoitettu eristettyyn kohtaan, joka on vaikea saavuttaa ja kohteessa täytyy olla energia lähde saatavilla energia harvesterille. Lopuksi ohjelmiston kehitysvaiheet on selitetty. Prototyyppi rakennettiin tutkimusryhmässä ja tämä tutkielma tarkastelee tutkimustietoa ja teknologioita liittyen prototyyppiin. Prototyyppi systeemi sisältää elektromagneettiseen induktioon perustuvan energia harvesterin. Harvesteri on yksi tutkielman pääosista, joten se vaatii tarkempaa tutkintaa. Muut projektin jäsenet tekivät testauksen ja rakensivat energia harvesterin ja tutkielma sisältää pintapuolisen katsauksen energia harvesterin käytöstä ja toiminnasta. Tutkielman toteutus vaihe keskittyy kehittämään ohjelmistoa Bluetooth Low Energy laitteille. Sen jälkeen, kun BLE teoria on opiskeltu seuraava vaihe on verrata ja testata kehitysympäristöjä ja lautoja käyttäen datansiirto ohjelmia. Ampiq Apollo3 SDK, Mbed Studio ja Arduino IDE:ä vertaillaan SparkFun Artemis laudoilla ja Arduino BLE laudoilla. Prototyypin tarkoitettu testausympäristö tulee olemaan auton renkaan sisäkehä, vaikuttaen optimaalisen BLE laudan valintaan joka rajoittaa kotelon kokoa ja prototyypin asennus aluetta. Seurauksena saatiin Mbed Studiossa kehitetty ohjelma, joka ei pystynyt luomaan BLE yhteyttä asettaen vertailun uuteen näkökulmaan. Tulos oli odottamaton ja näytti että vahvakaan taustatutkimus ei varmista toiminnallisuutta. Tämä ei estänyt käyttämästä sitä tuloksena ja jatkamaan kehitystä muilla ympäristöillä. Tulevaa työtä koskevat vaikutukset ja ideat dokumentoidaan seuraavaa kehittäjää varten. Kaksi muuta ympäristöä olivat toimivia ja mahdollistivat merkityksekkään vertailun. Erot lautojen välillä ovat kaikkein merkittävimmät, kun laudan käyttötarkoitus ja käytetty ympäristö otetaan huomioon. Esimerkiksi lautojen koot, muodot ja energiankulutus vaihtelevat. Bluetooth ominaisuudet ovat samalla tapaa saatavilla kaikissa laudoissa mutta niiden hyödyntäminen myös vaihteli laudoittain. Päättäen tutkielman ajatuksilla tulevaisuuden kehitys poluista energia harvesteri ja Bluetooth Low Energy sovelluksissa

Methods and Tools for Battery-free Wireless Networks

Embedding small wireless sensors into the environment allows for monitoring physical processes with high spatio-temporal resolutions. Today, these devices are equipped with a battery to supply them with power. Despite technological advances, the high maintenance cost and environmental impact of batteries prevent the widespread adoption of wireless sensors. Battery-free devices that store energy harvested from light, vibrations, and other ambient sources in a capacitor promise to overcome the drawbacks of (rechargeable) batteries, such as bulkiness, wear-out and toxicity. Because of low energy input and low storage capacity, battery-free devices operate intermittently; they are forced to remain inactive for most of the time charging their capacitor before being able to operate for a short time. While it is known how to deal with intermittency on a single device, the coordination and communication among groups of multiple battery-free devices remain largely unexplored. For the first time, the present thesis addresses this problem by proposing new methods and tools to investigate and overcome several fundamental challenges

Deploying RIOT operating system on a reconfigurable Internet of Things end-device

Dissertação de mestrado integrado em Engenharia Eletrónica Industrial e ComputadoresThe Internet of Everything (IoE) is enabling the connection of an infinity of physical objects to the Internet, and has the potential to connect every single existing object in the world. This empowers a market with endless opportunities where the big players are forecasting, by 2020, more than 50 billion connected devices, representing an 8 trillion USD market. The IoE is a broad concept that comprises several technological areas and will certainly, include more in the future. Some of those already existing fields are the Internet of Energy related with the connectivity of electrical power grids, Internet of Medical Things (IoMT), for instance, enables patient monitoring, Internet of Industrial Things (IoIT), which is dedicated to industrial plants, and the Internet of Things (IoT) that focus on the connection of everyday objects (e.g. home appliances, wearables, transports, buildings, etc.) to the Internet. The diversity of scenarios where IoT can be deployed, and consequently the different constraints associated to each device, leads to a heterogeneous network composed by several communication technologies and protocols co-existing on the same physical space. Therefore, the key requirements of an IoT network are the connectivity and the interoperability between devices. Such requirement is achieved by the adoption of standard protocols and a well-defined lightweight network stack. Due to the adoption of a standard network stack, the data processed and transmitted between devices tends to increase. Because most of the devices connected are resource constrained, i.e., low memory, low processing capabilities, available energy, the communication can severally decrease the device’s performance. Hereupon, to tackle such issues without sacrificing other important requirements, this dissertation aims to deploy an operating system (OS) for IoT, the RIOT-OS, while providing a study on how network-related tasks can benefit from hardware accelerators (deployed on reconfigurable technology), specially designed to process and filter packets received by an IoT device.O conceito Internet of Everything (IoE) permite a conexão de uma infinidade de objetos à Internet e tem o potencial de conectar todos os objetos existentes no mundo. Favorecendo assim o aparecimento de novos mercados e infinitas possibilidades, em que os grandes intervenientes destes mercados preveem até 2020 a conexão de mais de 50 mil milhões de dispositivos, representando um mercado de 8 mil milhões de dólares. IoE é um amplo conceito que inclui várias áreas tecnológicas e irá certamente incluir mais no futuro. Algumas das áreas já existentes são: a Internet of Energy relacionada com a conexão de redes de transporte e distribuição de energia à Internet; Internet of Medical Things (IoMT), que possibilita a monotorização de pacientes; Internet of Industrial Things (IoIT), dedicada a instalações industriais e a Internet of Things (IoT), que foca na conexão de objetos do dia-a-dia (e.g. eletrodomésticos, wearables, transportes, edifícios, etc.) à Internet. A diversidade de cenários à qual IoT pode ser aplicado, e consequentemente, as diferentes restrições aplicadas a cada dispositivo, levam à criação de uma rede heterogénea composto por diversas tecnologias de comunicação e protocolos a coexistir no mesmo espaço físico. Desta forma, os requisitos chave aplicados às redes IoT são a conectividade e interoperabilidade entre dispositivos. Estes requisitos são atingidos com a adoção de protocolos standard e pilhas de comunicação bem definidas. Com a adoção de pilhas de comunicação standard, a informação processada e transmitida entre dispostos tende a aumentar. Visto que a maioria dos dispositivos conectados possuem escaços recursos, i.e., memória reduzida, baixa capacidade de processamento, pouca energia disponível, o aumento da capacidade de comunicação pode degradar o desempenho destes dispositivos. Posto isto, para lidar com estes problemas e sem sacrificar outros requisitos importantes, esta dissertação pretende fazer o porting de um sistema operativo IoT, o RIOT, para uma solução reconfigurável, o CUTE mote. O principal objetivo consiste na realização de um estudo sobre os benefícios que as tarefas relacionadas com as camadas de rede podem ter ao serem executadas em hardware via aceleradores dedicados. Estes aceleradores são especialmente projetados para processar e filtrar pacotes de dados provenientes de uma interface radio em redes IoT periféricas

Personal sensor wristband for smart infrastructure and control

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, February 2013."February 2013." Cataloged from PDF version of thesis.Includes bibliographical references (p. 67-72).Despite the rapid expansion of computers beyond desktop systems into devices and systems in the environment around us, the control interfaces to these systems are often basic and inadequate, particularly for infrastructure systems. WristQue is a wearable interface for interacting with computerized systems in the environment, providing both explicit remote control with buttons, touch, and gestural interfaces, and automatic closed-loop control using environmental sensors on the device, fused with precise indoor location for context. By placing these sensors and controls on the wrist, they are generally able to sense the environment unobstructed and are conveniently within reach at all times. WristQue is able to continuously collect and stream sensor data through a wireless network infrastructure, including temperature, humidity, activity, light, and color. A 9-DoF inertial/ magnetic measurement unit can be enabled to use the WristQue as a wrist-based gestural interface to nearby devices. Location and orientation data is used to implement a pointing interface that the user can use to indicate a device to control. This interface was implemented and tested using the WristQue and a commercial UWB localization system. The other sensors on the WristQue were validated by collecting several days of environmental data and conducting several controlled experiments. With these capabilities, the WristQue can be used in a number of sensing and control applications, such as lighting and comfort control.by Brian D. Mayton.S.M