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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Wireless Control of Industrial Robot

Paulsson, Johan January 2020 (has links)
The purpose of this project was to investigate if it is possible to have local wireless control of an industrial robot. This was achieved by first doing a diversity of research. Based on the research, the project was conceptualized and a real-life product was developed showcasing the functionality. The standard robot set up as of today consists of three main parts: A robot, a control unit and a handheld controller device, called Teach Pendant. All of these parts are connected with long aggravating cables. The cables cause inconvenience and can in some cases introduce unnecessary risks in the factory. Can this hardware be removed, and an overall more convenient use case be developed? The product was developed by programming an application on a Windows tablet. Further, a Bluetooth Low Energy server was created to handle the communication between the tablet and the robot control unit. The final product consisted of a tablet, a single-board computer, a robot and a control unit. The tablet is what replaces the Teach Pendant as a handheld device. The tablet is connected to the singleboard computer via Bluetooth. The single-board computer acts as a Bluetooth server and sends out advertisements for the tablet to detect. When the tablet detects a nearby robot it can then connect to it and send start and stop commands. The server then forwards it to the control unit which finally sends the data to the robot control unit to execute. The project shows that it is possible to develop wireless robot control. It showcases a potential solution on how one could set it up. However, the final product developed had a simple functionality compared to the wired Teach Pendant. To manage the same capacity as the wired Teach Pendent, further development is required.
12

A design of low power wearable system for pre-fall detection

Rathi, Neeraj R. 08 March 2018 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Fall in recent years have become a potential threat to elder generation. It occurs because of side effects of medication, lack of physical activities, limited vision, and poor mobility. Looking at the problems faced by people and cost of treatment after falling, it is of high importance to develop a system that will help in detecting the fall before it occurs. Over the year's, this has influenced researchers to pursue the development to automatic fall detection system. However, much of existing work achieved a hardware system to detect pre and post fall patterns, the existing systems deficient in achieving low power consumption, user-friendly hardware implementation and high precision. Growth in medical devices can be seen in recent years. Today's medical devices aim to increase the life expectancy and comfort of human being. The systems are designed to be made reliable by improving the performance, optimizing the size and minimizing the energy consumption. For wearable technologies, power consumption is an important factor to be considered during system design. High power consumption decreases the battery life, which leads to poor comfortability. The purpose of this research is to develop a system with low power consumption to detect human falls before they happen. This research points towards the development of dependable and low power embedded system device with easy to wear capabilities and optimal sensor structure. In this work, we have developed a device using motion sensor to sense the subjects linear and angular velocity, communication sensor to send the fall related information to caretaker, and signal sensors to communicate and update user about device information. The designed system is triggered on interrupts from motion sensor. As soon as the system is triggered by an interrupt signal, users balanced and unbalanced states gets monitored. Once the unbalanced state is designated, the system signifies it as fall by setting a fall flag. The fall decision parameters; pitch, roll, complementary pitch, complementary roll, Signal Vector Magnitude (SVM), and Signal Magnitude Area (SMA) are layered to classify subject's different body posture. This helps the system to differentiate between activity of daily living (ADL) and fall. When the fall flag is set, the device sends important information like GPS location and fall type to caretaker. Early fall detection gives milliseconds of time to initiates the preventive measures. The system was designed, developed, and constructed. Near 100% sensitivity, 96% accuracy, and 95% specificity for fall detection were measured. The system can detect Front, Back, Side and Stair fall with consumption of 100_A (650_A with BLE consumption) in deep sleep mode, 6.5mA in active mode with no fall, and 14.5mA, of which 8.5 mA is consumed via the BLE when fall is declared in active mode. The power consumption was reduced because the integrated wireless communication devices consumed power only when the fall is triggered, giving the device a potential to communicate wirelessly.
13

The use of Bluetooth Low Energy Technology for Cost-Effective Construction Equipment Tracking

Mukhtar, Muhammad Hamza 23 August 2022 (has links)
No description available.
14

Development and Characterization of an IoT Network for Agricultural Imaging Applications

Wahl, Jacob D 01 June 2020 (has links) (PDF)
Smart agriculture is an increasingly popular field in which the technology of wireless sensor networks (WSN) has played a large role. Significant research has been done at Cal Poly and elsewhere to develop a computer vision (CV) and machine learning (ML) pipeline to monitor crops and accurately predict crop yield numbers. By autonomously providing farmers with this data, both time and money are saved. During the past development of a prediction pipeline, the primary focuses were CV and ML processing while a lack of attention was given to the collection of quality image data. This lack of focus in previous research presented itself as incomplete and inefficient processing models. This thesis work attempts to solve this image acquisition problem through the initial development and design of an Internet of Things (IoT) prototype network to collect consistent image data with no human interaction. The system is developed with the goals of being low-power, low-cost, autonomous, and scalable. The proposed IoT network nodes are based on the ESP32 SoC and communicate over-the-air with the gateway node via Bluetooth Low Energy (BLE). In addition to BLE, the gateway node periodically uplinks image data via Wi-Fi to a cloud server to ensure the accessibility of collected data. This research develops all functionality of the network, comprehensively characterizes the power consumption of IoT nodes, and provides battery life estimates for sensor nodes. The sensor node developed consumes a peak current of 150mA in its active state and sleeps at 162µA in its standby state. Node-to-node BLE data transmission throughput of 220kbps and node-tocloud Wi-Fi data transmission throughput of 709.5kbps is achieved. Sensor node device lifetime is estimated to be 682 days on a 6600mAh LiPo battery while acquiring five images per day. This network can be utilized by any application that requires a wireless sensor network (WSN), high data rates, low power consumption, short range communication, and large amounts of data to be transmitted at low frequency intervals.
15

IoT - based Microseismic Detector

Lindgren, Anton January 2023 (has links)
Rockfall, which is the detachment of rocks from a mountain, is a major hazard in the mining industry. To help combat this issue, this thesis aims to develop a sensor platform that is able to detect both the potential risk for rockfall and if any rocks do hit the ground. The platform requires wireless communication in order to output relevant information and in order to be part of an IoT-network of sensors.The design of the platform used three different sensors, a geophone, an accelerometer and a microphone. The main focus of the design process was to keep the platform low power, enabling long operation times. The final design had data output from both the microphone and accelerometer, with the accelerometer able to pick up the impact from a falling barbell. Wireless transmission of data is possible for up to 7.5 meters using Bluetooth Low Energy. The low power design was met, with an average current consumption of 26 milliamperes during transmission using Bluetooth Low Energy. That gives a theoretical operation time of 27 days with the battery used. As the accelerometer can pick up a falling object and with a theoretical lifetime of 27 days for the platform, it can be argued that the goals, except for detecting potential risk for rockfall, were met. In order to properly function, however, the platform needs more development, but the most important conclusion of the work is that it seems possible to build this type of platform. Further research and development outside the scope of the thesis is connecting several platforms together.
16

Dynamic configuration of Bluetooth mesh : A master thesis in electrical engineering

Fricking, August January 2022 (has links)
When choosing what IoT protocol to use today, there are lots of choices. If a mesh type network is chosen, Bluetooth mesh might be a possible candidate. Bluetooth mesh without correctly configured parameters can however suffer from congestion and packet loss if the network is very dense or consists of many nodes. This can be counteracted by choosing which nodes should be relays more carefully, as well as setting the re-transmission count and Time To Live (TTL) based on the current topology of the network. If the nodes in the network change position or are added/removed regularly, it is impossible to set the parameters optimal for all the possible network layouts. This is where a dynamic configuration comes in handy. In this master thesis a custom control model was created which implemented the K2 Pruning algorithm for relay selection, custom heartbeats for a dynamic TTL on each node, and a static re-transmission count for message originators and relays. A possible way to implement a dynamic re-transmission count is also discussed, as well as how the dynamic configuration could be autonomous without the need of physical interaction when reconfiguring the network. The implemented dynamic configuration tested on a physical system of 33 nodes was partly unsuccessful, but still provided improved Packet Delivery Ratio (PDR), reduced message delay, and useful knowledge for future implementations of a dynamic configuration. The K2 Pruning algorithm failed in choosing relays correct and quickly due to congestion during the neighbor information exchange needed to run the algorithm. Therefore, a different relay selection algorithm is suggested for future models or the refrain of acknowledged messages during the neighbor information exchange phase.
17

ROLE DE L'AVERSION GUSTATIVE CONDITIONNEE ET DE LA SATIETE DANS LA DEPRESSION DE LA PRISE ENERGETIQUE INDUITE PAR LES REGIMES HYPERPROTEIQUES CHEZ LE RAT

Bensaid, Ahmed 17 June 2003 (has links) (PDF)
LES REGIMES HYPERPROTEIQUES INDUISENT UNE DEPRESSION DE LA PRISE ENERGETIQUE CHEZ LE RAT. LES MECANISMES SOUS-TENDANT CETTE DEPRESSION SONT MAL CONNUS. L'OBJET DE CETTE THESE EST D'ANALYSER LES ROLES RESPECTIFS DE LA PALATABILITE, DE LA SATIETE, ET DE L'AVERSION GUSTATIVE CONDITIONNEE DANS CE PHENOMENE. LAPPLICATION DE LA METHODE DENREGISTREMENT DE LA PRISE ALIMENTAIRE ET DE VIDEO ANALYSE A DES RATS, LORS DE LA TRANSITION DUN REGIME NORMOPROTEIQUE (14%) VERS UN REGIME HYPERPROTEIQUE (>50%), MONTRE DES MODIFICATIONS TRANSITOIRES DU COMPORTEMENT DE LANIMAL LORS DU PREMIER JOUR : REDUCTION DE LA TAILLE DU REPAS, DIMINUTION DE LA VITESSE DINGESTION ET MODIFICATION DE LA SEQUENCE COMPORTEMENTALE DE SATIETE. APRES ADAPTATION AU REGIME HYPERPROTEIQUE, LA QUANTITE DENERGIE INGEREE AVEC LE REGIME HYPERPROTEIQUE RESTE NEANMOINS EN DEÇA DE CELLE INGEREE EN REGIME NORMOPROTEIQUE ET LE POIDS DES ANIMAUX RECEVANT UN REGIME HYPERPROTEIQUE EST PLUS FAIBLE. DES LE SECOND OU TROISIEME JOUR, SELON LA PROTEINE ALIMENTAIRE UTILISEE, LA SEQUENCE COMPORTEMENTALE DE SATIETE N'EST PLUS DIFFERENTE DE CELLE INDUITE PAR UN REPAS NORMOPROTEIQUE. L'ABSENCE D'AVERSION GUSTATIVE CONDITIONNEE ET LA PRESENCE D'UN EFFET SATIETOGENE DES PROTEINES A ETE CONFIRMEE QUAND LES RATS, ELEVES SUR UN REGIME NORMOPROTEIQUE, ET RECEVANT TROIS REPAS PAR JOUR, INGERENT UN EN-CAS PROTEINE. LES PROTEINES DEPRIMENT PLUS LA PRISE ALIMENTAIRE LORS DU REPAS SUIVANT QUE LES GLUCIDES. LANALYSE DE LA SEQUENCE ALIMENTAIRE MONTRE QUE LA DIMINUTION DE LA TAILLE DU REPAS INDUITE PAR LES CHARGES PROTEIQUES 35% ET 50% EST DU A UN EFFET SATIETOGENE ET NON A UNE AVERSION GUSTATIVE CONDITIONNEE. NOTRE ETUDE A AUSSI MONTRE QUE PLUSIEURS PARAMETRES BIOCHIMIQUES (AMINOACIDEMIE TOTALE, ACIDES AMINES BRANCHES ) OU HORMONAUX (LEPTINEMIE) SONT SUSCEPTIBLES DETRE A LA BASE DES SIGNAUX ENVOYES AU CERVEAU POUR INITIER LA BAISSE DE PRISE ALIMENTAIRE. EN RESUME, LES RATS NE DEVELOPPENT PAS UNE AVERSION GUSTATIVE CONDITIONNEE VIS A VIS DU REGIME HYPERPROTEIQUE. LES MODIFICATIONS DE LA PRISE ALIMENTAIRE ET DU COMPORTEMENT, CORRESPONDENT PLUS A UN EFFET SUR-SATIETOGENE DU REGIME HYPERPROTEIQUE COMBINE A SA FAIBLE PALATABILITE ET A UNE NECESSAIRE ADAPTATION METABOLIQUE DE L'ANIMAL A CE REGIME. NOS RESULTATS, QUE CE SOIT DANS LE CADRE DE L'INGESTION D'UN REGIME HYPERPROTEIQUE OU, PLUS SIMPLEMENT LORS D'UN REPAS, MONTRE QUE L'INGESTION DE PROTEINES S'ACCOMPAGNE D'UN EFFET SATIETOGENE QUI RESTE A EXPLIQUER
18

Vzdáleně řízený termostat / Remotely controlled thermostat

Závodný, Vilém January 2014 (has links)
The aim of my thesis is to understand the manufactured thermostats and design own thermostat to allow the most basic possibilities classical thermostats plus setup and management via web interface. It is a realization of a small web server that works closely with hardware peripherals. In addition, the web interface is still possible to manage a Web server of TFT LCD screen or applications for smart phone with Android. In addition, the thermostat allows the temperature reading from the BLE modules. All temperatures are continuously stored in a database and graphically processed.
19

Portabel EKG : Med möjlighet att trådlöst överföra och behandla EKG-data / Wearable ECG : With the capability to wirelessly transfer and process ECG data

Bengtsson, Richard, Lindgren, Joel January 2020 (has links)
Hjärt-kärlsjukdomar är den vanligaste dödsorsaken i Sverige och om dessa hjärtfel kan konstateras i ett tidigt stadie är chansen för att överleva hos den drabbade mycket hög. Detta projekt gick ut på att designa ett modulbaserat och portabelt EKG-system som kan mäta minst sju avledningar och trådlöst överför EKG-data till en dator eller mobil där det sparas för analys vid ett senare tillfälle. De tre moduler som använts i projektet är ett demokort från Texas Instrument, som bygger runt deras A/D-omvandlar ADS1298 konstruerad för att sampla EKG-data, en Nordic Thingy 52 som trådlöst via Bluetooth Low Energy överför det data som samplats samt en Raspberry Pi för lagring och datahantering. Mätvärdena ska sparas i en fil som senare ska kunna användas för att visualisera ett EKG-komplex.   Arbetet inleddes med en förstudie samt en designspecifikation som en grund till EKG-systemet. När systemet var implementerat utfördes en rad olika EKG för att kontrollera dataöverföring samt att filtrering var korrekt. Det färdiga EKG-systemet visade sig uppfylla de krav som ställdes i början av projektet och har mycket hög förbättringspotential inför framtiden. / Cardiovascular disease is the most common cause of death in Sweden and if these heart defects can be diagnosed at an early stage, the chance of survival in the sufferer is very high. This project involved designing a modular and portable ECG system that can measure at least seven leads and wirelessly over Bluetooth Low Energy transfer ECG data to a computer or mobile where it can be saved for later analysis. The three modules used in the project are a demonstration board from Texas Instrument, which builds around the analog to digital converter ADS1298 designed to collect ECG data, Nordic Thingy 52 which wirelessly via Bluetooth Low Energy transmits the collected ECG data and a Raspberry Pi for storage and data management. The measured values ​​must be saved in a file that can later be used to visualize an ECG complex.  The work began with a feasibility study and a design specification as a basis for the ECG system. When the system was implemented several different ECGs was done to test so that data transfer and filtering were correct. The completed ECG system proved to meet the requirements set at the beginning of the project and has a very high potential for improvement in the future.
20

Trådlösa tekniker i tidskritiska system : En experimentell jämförelse mellan Zigbee 3.0 och Bluetooth Low Energy 5.2 / Wirelss technologies in time-critical system : An experimental comparison between Zigbee 3.0 and Bluetooth Low Energy 5.2

Hsertawbu, Naw Michey Hsalehleh, Sabbagh, Marwa January 2021 (has links)
Examensarbetet genomfördes tillsammans med företaget Rol Ergo. Syftet med studien var att analysera Zigbee 3.0 och Bluetooth Low Energy 5.2 och deras lämplighet i tidskritiska system genom att studera latensen och förhållandet mellan signalstyrkan och avståndet mellan de två kommunikationsprodukter. Datainsamlingen genomfördes med en experimentell studie och utifrån kunskap som framskaffats har ett visst antal bestämda experiment utförts för att svara på frågeställningarna som ställs.  Datainsamlingen visar att både maxlatensen och typiska latensen hos Zigbee är lägre än maxlatens och typiska latens för Bluetooth Low Energy. Datainsamlingen för signalstyrkan visar att Bluetooth Low Energys signalstyrka blir mer påverkad av avståndet mellan kommunikationsprodukterna än vad Zigbees blir. Det visar även att den optimala förhållande mellan signalstyrkan och avståndet hos Zigbee är bättre än hos Bluetooth Low Energy.  Slutsatsen av arbetet är att Zigbee är mer lämpad för tidkritiska system än Bluetooth Low Energy då låg latensen prioriteras. Zigbee är även mer lämpad då lång distansen prioriteras men då bör signalstyrkan ligga runt -50dBm. Bluetooth Low Energy är dock mer lämpad då lång distans inte prioriteras och signalstyrkan inte behöver vara utmärkt för att kunna kommunicera.  Begränsningarna för arbetet är att Bluetooth Low Energy och Zigbee endast har prövats på utvecklingskortet nRF5340 DK.  På grund av den begränsade tiden så har endast ett antal bestämda experiment som har föreslagits av rådgivare på Rol Ergo utförts. / The thesis has been conducted together with  Rol Ergo company. The purpose of this study is to analyse Zigbee 3.0 and Bluetooth Low Energy 5.2 and their suitability for time-critical systems, by studying latency and the relations between signal strength and distance between two communication products. The data collection was completed by an experimental study. By using knowledge that has been collected for the study, sets of experiments will be performed to answer the research questions.  Results of the collected data indicate that both the maximum latency and the typical latency for Zigbee is significantly lower than for Bluetooth Low Energy. The collected data for signal strength shows that the signal strength for Bluetooth Low Energy is more affected by distance between the communication product, than Zigbee’s is. It also shows that the optimal ratio between signal strength and distance for Zigbee is better than for Bluetooth Low Energy. The conclusion of the study shows Zigbee to be a more suitable for time-critical systems compared to Bluetooth Low Energy when low latency is being prioritized. Zigbee is also more suitable for time-critical systems when long distance is being prioritized, however the signal strength must then be around -50 dBm. Bluetooth Low Energy is more suitable when long distance is not the priority, and the signal strength does not have to be excellent to be able to communicate.  The limitations for this thesis are that Bluetooth Low Energy and Zigbee will only be tested on the nRF5349 Development Kit. given limited time, only a certain of experiments, whereas some have been suggested by advisors from Rol Ergo, has been carried out.

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