Non-cash payment method using QR codes in an automated microcontroller-based vending machine

This thesis report is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2014.Cataloged from PDF version of thesis report.Includes bibliographical references (page 42).The purpose of this thesis project is to implement a micro-controller-based automated vending machine which uses codes as a method for authorization of payments of online accounts to implement a non cash payment method for a contact less mobile payment system. Once a user places his/her order in the vending machine a QR (quick response) code is generated which holds all of the information of the user's order. An application is used to scan that QR code. The QR code once scanned with that application, populates the information of the order and sends that information to a web server only after the user’s approval for using their online account for payment. This web server takes this input from the user and processes the payment. The transaction is made from the web server with an online payment platform which holds the user's account. After the transaction is made, a second QR code, which stores the user's order information and authorization, is sent to the user's application from the server. User displays the QR code and it is scanned by the vending machine's scanner to release the desired product(s) thus making the process contact less.Md. Shahidur RahmanShamiha Yeasin BintuSidratul AmanB. Electrical and Electronic Engineerin

Compact Multi-Coil Inductive Power Transfer System with a Dynamic Receiver Position Estimation

Inductive power transfer (IPT) systems with tolerance to the lateral misalignment are advantageous for enhancing the transmitted power, usability and security of the system. In this thesis, a misalignment tolerant multi-coil design is proposed to supply stationary and dynamic battery-free wireless devices. A compact architecture composed of individually switchable 3 layers of printed coils arranged with overlap for excellent surface coverage. A hybrid architecture based on three compact AC supply modules reduces the supply circuit complexity on the sending Seite 2 von 4side. It detects the position of the receiver coil quickly, controls the activation of the transmitting coils and estimates the next receiver position. The proposed architecture reduces the circuit footprint by a factor of 62% compared to common architectures. A transmitter coil activation strategy is proposed based on the detection of the transmitting coils voltage and communication between sending side and receiving side to detect devices to supply nature and position and to differentiate them from other conductive objects in the sending area to the supplying security. The experimental results prove that the proposed architecture has a good performance for different trajectories when the device speed does not exceed 15 mm/s. Besides, the maximum detection time for the initial device position is about 1.6 s. The maximal time interval to check the transmitter coils is around 0.7 s.:1. INTRODUCTION 2. THEORETICAL BACKGROUND 3. STATE OF THE ART OF MULTI-COIL IPT SYSTEMS 4. NOVEL DESIGN OF A MULTI-COIL IPT SYSTEM 5. MULTI-COIL ACTIVATION PROCEDURE 6. EXPERIMENTAL INVESTIGATIONS 7. CONCLUSION AND OUTLOOKInduktive Energieübertragungssysteme (IPT) mit Toleranz gegenüber seitlichem Versatz sind vorteilhaft, um die übertragene Leistung, die Nutzbarkeit und die Sicherheit des Systems zu verbessern. In dieser Arbeit wird ein versatztolerantes Multispulen-Design vorgeschlagen, um stationäre und dynamische batterielose drahtlose Geräte zu versorgen. Die kompakte Architektur besteht aus 3 einzeln schaltbaren Schichten gedruckter Spulen, die überlappend angeordnet sind, um eine hervorragende Oberflächenabdeckung zu gewährleisten. Eine hybride Architektur, die auf drei kompakten AC-Versorgungsmodulen basiert, reduziert die Komplexität der Versorgungsschaltung auf der Senderseite. Sie erkennt die Position der Empfängerspule schnell, steuert die Aktivierung der Sendespulen und schätzt die nächste Empfängerposition. Die vorgeschlagene Architektur reduziert den Platzbedarf der Schaltung um einen Faktor von 62 % im Vergleich zu herkömmlichen Architekturen. Es wird eine Aktivierungsstrategie für die Sendespulen vorgeschlagen, die auf der Erkennung der Spannung der Sendespulen und der Kommunikation zwischen Sende- und Empfangsseite basiert, um die Art und Position der zu versorgenden Geräte zu erkennen und sie von anderen leitfähigen Objekten im Sendebereich zu unterscheiden. Die experimentellen Ergebnisse zeigen, dass die vorgeschlagene Architektur eine gute Leistung für verschiedene Trajektorien hat, wenn die Geschwindigkeit der Geräte 15 mm/s nicht überschreitet. Außerdem beträgt die maximale Erkennungszeit für die anfängliche Geräteposition etwa 1,6 s. Das maximale Zeitintervall für die Überprüfung der Senderspulen beträgt etwa 0,7 s.:1. INTRODUCTION 2. THEORETICAL BACKGROUND 3. STATE OF THE ART OF MULTI-COIL IPT SYSTEMS 4. NOVEL DESIGN OF A MULTI-COIL IPT SYSTEM 5. MULTI-COIL ACTIVATION PROCEDURE 6. EXPERIMENTAL INVESTIGATIONS 7. CONCLUSION AND OUTLOO

Contactless Measurement of Angular - Speed

The control technology has been improved to enormous scales so far. People are trying to apply control over everything they do, so that the level of accuracy and efficiency increase. The simplest form of control could be a control of a rotating shaft. We might want to keep its speed stable at some rps (rounds per second). This can be achieved in numerous methods. Regardless of any method chosen, the first step to achieve this goal would always be being able to measure the speed and then to apply control measures to it. In this project, I aminvestigating contactless measurement ofangular speed of a rotating shaft. My main objective is to demonstrate how to measure the angular speed of a rotating shaft contactlessly. Contactless measurement of angular speed is particularly critical when dealing with load-sensitive devices such as mobile antennas. I am achieving the contactless measurement through using IR (infrared) emitter-detector circuitry. The IR pair generates pulses, which are galvanized by the rotation of the shaft. Slots on a disk mounted to the shaft permits light transmission between IR emitter and detector, which are placed on both sides of the disk. Hence, when the disk rotates it is possible to get stream of pulses from the circuitry. I used a PIC microcontroller to accept the pulses and obtain the angular speed in terms of rps. This value is then displayed on 7-segment LEDs. Lastly, this project involved a lot of microprocessor concepts. I tried my best to present concepts involvedas comprehensible as possible. I expectthe reader to have no difficulty while reading it

Micro air vehicles energy transportation for a wireless power transfer system

The aim of this work is to demonstrate the feasibility use of an Micro air vehicles (MAV) in order to power wirelessly an electric system, for example, a sensor network, using low-cost and open-source elements. To achieve this objective, an inductive system has been modelled and validated to power wirelessly a sensor node using a Crazyflie 2.0 as MAV. The design of the inductive system must be small and light enough to fulfil the requirements of the Crazyflie. An inductive model based on two resonant coils is presented. Several coils are defined to be tested using the most suitable resonant configuration. Measurements are performed to validate the model and to select the most suitable coil. While attempting to minimize the weight at transmitter’s side, on the receiver side it is intended to efficiently acquire and manage the power obtained from the transmitter. In order to prove its feasibility, a temperature sensor node is used as demonstrator. The experiment results show successfully energy transportation by MAV, and wireless power transfer for the resonant configuration, being able to completely charge the node battery and to power the temperature sensor.Peer ReviewedPostprint (published version

Dynamic modelling and control schemes for current-source resonant converters

Versió amb diverses seccions retallades, per drets de l'editorThis thesis focuses on the control methods applied to current source resonant converters, especially in two different applications of switching power supplies and wire-less power transfer systems. In fact, the existing applications are mostly working with voltage source resonant converters. For voltage-source resonant converters, many control strategies have been analyzed and investigated, turning this into a mature technology nowadays. The current-source resonant converter is an alternative solution as they offer well-known advantages such as non-pulsating input current, low stress for switches, simple driving circuitry, and short circuit protection capabilities. However, there is an obvious lack of control methods applicable to current-source resonant converters. In addition, obtaining an appropriate dynamic model to be used in control design is the other challenging issue in this field. Hence, the objectives of this thesis are used to fill these gaps. The proposed control schemes are: - Frequency modulation control scheme applied to a DC/DC current-source parallel resonant converter. - Sliding mode control scheme with amplitude modulation applied to a DC/DC current-source parallel resonant converter. - A control scheme for a multiple-output DC/DC current-source parallel resonant converter. - A communication-less control scheme for a variable air-gap wireless energy transfer system using a current-source resonant converter.Esta tesis doctoral está centrada en los métodos de control aplicados a los convertidores resonantes con fuente de corriente, especialmente en dos aplicaciones distintas como son fuentes de alimentación conmutadas y sistemas de transferencia de energía sin hilos. De hecho, las aplicaciones existentes trabajan principalmente con convertidores alimentados mediante fuentes de tensión. Para los convertidores resonantes con fuente de tensión, se han analizado muchas estrategias de control en la literatura, lo que hace hoy en día que esta sea una tecnología madura. El convertidor resonante con fuente de corriente es una solución alternativa, que ofrece ventajas conocidas como corriente de entrada no pulsante, baja tensión para interruptores, circuitos de conducción sencillos y capacidades de protección contra cortocircuitos. Sin embargo, existe una falta evidente de métodos de control aplicables a los convertidores resonantes con fuente de corriente. Además, otro desafío en este tema es la obtención de modelos dinámicos apropiados para el diseño del control. Por lo tanto, los objetivos de esta tesis se utilizan para llenar estos vacíos. Los esquemas de control propuestos son: - Esquema de control en frecuencia aplicado a un convertidor resonante paralelo con fuente de corriente para reguladores de tensión en continua - Esquema de control en modo de deslizamiento con modulación de amplitud aplicado a un convertidor resonante paralelo con fuente de corriente para reguladores de tensión en continua. - Esquema de control para un convertidor resonante paralelo con fuente de corriente para la regulación de tensión en continua de varias salidas. - Esquema de control sin comunicaciones para un sistema de transferencia de energía sin hilos con un transformador con entrehierro variable basado en un convertidor resonante con fuente de corriente.Postprint (published version

Advanced spacecraft electrical power systems applying solid state technology Final report, 1 Jan. - 31 Dec. 1970

Solid state system for advanced spacecraft electric power distribution and contro

DJI Drone Modification

For this project, we set out to create a lightweight carrying case that would be mounted to a DJI Phantom 3. This case is designed to transport small packages, such as medications, from a delivery vehicle to their final destination. Based on our maximum drone lifting capacity of 600 grams, our case, servomotor, and contents had to weigh less than or equal to that value. The coronavirus pandemic has led to an increase in contactless delivery options along with the push for immunocompromised people to avoid contact with people that may be sick. Our product would help transport necessary supplies to those that have a difficulty leaving their homes to get them. We also envision the case to be scalable based on the size and lifting capacity of the drone. We used multiple design revisions to create our ideal design. This design has two release mechanisms; a manual option with a sliding clip and a powered option with a servomotor that is integrated into the control of the drone. To integrate additional servo inputs to the drone, we need a NAZA-M Lite flight controller. Since our drone did not come standard with this flight controller, we chose to forgo these changes to the drone and to explain how the flight controller would be integrated and programmed. Our final design reflects this change, but still includes the cut out for the servomotor on the front side. Our prototype combines the manual release mechanism and the powered release mechanism. The servomotor can be added, and the manual clip can be moved to the open position to create the powered release. Future designs would remove the manual clip to create the powered release. When our final design and testing were complete, we completed a product that met our initial goals and was fully functional in testing