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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.
61

Embedded GUI Library Development

Dreborg, Sofia January 2022 (has links)
This project aimed to create a simple open-source embedded graphical user interface library that could be used on more or less any microcontroller platform. The programming language was intended to be C++ for the GUI but as the project evolved C was chosen above C++. This was a decision based primarily on the fact that STM's development environment, STMCubeIDE, is less compatible with C++. The IDE offers great hardware support which in the end was more important than the advantages given by C++. The hardware used in this project was an STM32F469 microcontroller. It has an ARM CortexM4 processor core and 2 Mbyte of flash memory and 384 Kbytes of RAM. Wrapper functions for the Board Support Package, BSP, were written as a part of the library to allow easy access tothe BSP needed for the hardware configuration. The first part of the project goal was achieved, a simple GUI library was created. The resulting GUI library supports user interaction through buttons, it can display the current time andvisualizes given data in graphs. The graph function can display the data live, as a scatter plot, a bar plot and a line plot. The library also supports an alarm function that allows the user to decide what will happen after the alarm time is up. However, even though the GUI library was written to be device-independent, the product has not been tested on other platforms. For further development, this GUI library could be tested on another microcontroller. This would provide answers to how much software changes are needed to make the product as hardwareindependent as possible. To make the library lighter and faster, there is a possibility of optimizing the GUI core.
62

Hardwarová akcelerace šifrování / Hardware Accelerating of Encryption Algorithm

Hradil, David January 2007 (has links)
The goal of this thesis is to design a hardware realization of circuit which will implement the AES algorithm. A motivation was to make an acceleration against the classic software encryption. The acceleration is achieved by special designed parts of the circuit, which correspond to particular operations of the AES algorithm. First, there was necessary to design the circuit. In the next step there was a need to describe the designed circuit by the VHDL language. Then the circuit was simulated and synthesized. Due to comparing the circuit with software processing a software implementation was created. Both implementations were created for the FITKit platform. The hardware implementation is made by the FPGA technology and the software implementation is realized in a microcontroller. The result of the thesis is almost one thousandfold acceleration against the classic software encryption.
63

FPGA-Based IR Localization Sensor

Susanto, Samuel I. 31 August 2018 (has links)
No description available.
64

An Intelligent Lead Acid Battery Management System for Solar and Off-Peak Energy Storage

Ming-Chieh, Chen January 2012 (has links)
No description available.
65

Encryption of Computer Peripheral Devices

Norman, Kelly Robert 20 March 2006 (has links) (PDF)
Computer peripherals, such as keyboards, scanners, printers, cameras, and Personal Data Assistants (PDAs) typically communicate with a host PC via an unencrypted protocol, leaving them vulnerable to eavesdropping techniques, such as keyloggers. An encryption system was developed that is simple enough to be used in peripherals that do not have large amounts of processing power and memory. A software driver loaded in the operating system of the host computer communicates with a simple 8-bit microcontroller in the peripheral device. The driver handles key generation, key exchange, and provides decrypted data to the operating system. A key exchange protocol allows the driver and microcontroller to securely exchange randomly generated keys. The system can function without user intervention, but will alert a user if a non-encrypting or non-authorized peripheral device is detected. The system is designed to be implemented over a variety of interfaces including PS/2, RS-232, TCP/IP over Ethernet, 802.11, and Bluetooth. A demonstration system was built, which encrypts data on the PS/2 bus between a keyboard and the host computer. Several ciphers were considered for use in encryption. The RC4 cipher was selected for encrypting and decrypting the data in a demonstration system because of it's speed and efficiency when working with 8-bit data. The driver and the microcontroller share a hard-coded key, which is used to encrypt a randomly generated session key, in order to provide a secure exchange of the session key. The demonstration system performs well, without introducing enough latency to be noticed by the user, and the microcontroller is idle over 95% of the time, even when a fast typist is using the keyboard.
66

Biomechanical Applications and Modeling of Quantum Nano-Composite Strain Gauges

Remington, Taylor David 01 April 2014 (has links) (PDF)
Biological tissues routinely experience large strains and undergo large deformations during normal physiologic activity. Biological tissue deformation is well beyond the range of standard strain gauges, and hence must often be captured using expensive and non-portable options such as optical marker tracking methods that may rely upon significant post-processing. This study develops portable gauges that operate in real time and are compatible with the large strains seen by biological materials. The new gauges are based on a relatively new technique for quantifying large strain in real-time (up to 40 %) by use of a piezoresistive nano-composite strain gauge. The nano-composite strain gauges (NCSGs) are manufactured by suspending nickel nanostrands within a biocompatible silicone matrix. The conductive nickel filaments come into progressively stronger electrical contact with each other as the NCSG is strained, thus reducing the electrical resistance that is then measured using a four-probe method. This thesis summarizes progress in the understanding, design and application of NCSGs for biomechanical applications. The advanced understanding arises from a nano-junction-level finite element analysis of gap evolution that models how the geometry varies with strain in the critical regions between nickel particles. Future work will incorporate this new analysis into global models of the overall piezoresistive phenomenon. The improvements in design focused on the manufacturing route to obtain a reliable thin and flexible gauge, along with a modified connection and data extraction system to reduce drift issues that were present in all previous tests. Furthermore, a pottable data logging system was developed for mobile applications. Finally, a method of analyzing the resultant data was formulated, based upon cross-correlation techniques, in order to distinguish between characteristic wave-forms for distinct physical activities. All of these improvements were successfully demonstrated via a gait-tracking system applied to the insole of standard running shoes.
67

Design of Inexpensive and Easy to Use DIY Internet of Things Platform

Jaffe, Samuel R 01 June 2016 (has links) (PDF)
This thesis focuses on the design and implementation of a new, inexpensive, and less complex system for a Do-It-Yourself (DIY) Internet of Things (IoT) platform. The hardware aspects focus on a new chip called the ESP8266 which contains both microcontroller and WiFi connectivity capabilities in an extremely affordable package. The system uses the Arduino IDE to program the ESP8266, which is known to be an extremely user-friendly environment. All other software is both free and easy to use. Past methods of creating IoT projects involved either expensive hardware, often ranging from $50-$100 per node, or complicated programming requiring a full computer, or a constant connection to an immobile power source. This method costs as little as $2.50, can last for months or even years off of batteries, can be smaller than a quarter, and only requires a few lines of code to get data moving, making this platform much more attractive for ubiquitous use.
68

Development of a Low-Cost, Photovoltaic-Powered, Automated Water Recovery System

Daley, David E. 01 August 2021 (has links) (PDF)
An existing water filtration system at the Channel Islands Marine & Wildlife Institute (CIMWI) wastes approximately 25 gallons of water per day rinsing out solid waste under light load. To reduce CIMWI’s water and energy consumption, an automated system was designed and built to recover the rinse water and return it to the existing filtration loop. Models for fluid system requirements, basic energy needs, and photo- voltaic energy generation were created to aid in component selection. Basic sensors and electronics were programmed in Python for use with a Raspberry Pi single board computer to collect and process water recovery data over time. Pump automation and data acquisition energy needs were met with a 100W photovoltaic module, pulse width modulation (PWM) charge controller, and an absorbed glass mat (AGM) battery. A prototype system, $732 in total cost, was installed and was found to recover 19 gallons of water over the initial 30-hour testing period under light load. Models and software developed for this project could be adapted to aid in the creation of similar water recovery systems.
69

Satisfying Distributed Joint Control Timing Constraints

Stelmack, Maxwell Asher 23 February 2024 (has links)
When controlling the real-time system that is a robotic joint, reliability is the chief concern. Implementing controllers via embedded software imposes several limitations on the controller frequency, such as algorithm latency and supplemental processes (like networking) competing for execution time. If these obstacles prevent a controller from finishing a cycle before its period expires, stability cannot be guaranteed. A developer of embedded software controls ought to be able to prove the timeliness of the controller based on analysis and validation. Otherwise, the choice of controller frequency is arbitrary, without any guarantee of stability in worst-case scenarios. This work realized a truly distributed control system for a humanoid robot by migrating a portion of the joint controller to the low-level. While the central computer is still responsible for determining a joint torque to properly realize whole-body objectives, the low-level processor executes force control locally to produce that torque via a linear actuator. Decoupling the force controller from networking reduced its latency and variability, allowing it to execute several times between receiving desired forces. Furthermore, a real-time operating system was added on top of the existing firmware to enforce and verify timing constraints. Preemptive threading modules within the real-time kernel allow the processor to prioritize controller execution above all other activities, aiding its routine completion. The chosen RTOS provides powerful instrumentation and debugging tools to efficiently verify proper execution and quickly resolve errors. These changes allowed the controller to demonstratively operate at a greater frequency with a full guarantee that timeliness is enforced under all possible circumstances. Verification was performed on a robotic joint test stand to prepare for deployment on a full-scale humanoid robot. / Master of Science / A "control algorithm", or simply "controller", can be made to balance a humanoid robot by taking a snapshot of the robot's pose and motion to calculate how to manipulate each motor to maintain stability. This process repeats many times per second. The precise rate is a design choice termed as the controller's "frequency". While a higher frequency generally yields better performance, too great a frequency means the algorithm cannot finish before it is time to repeat, resulting in malfunction. This work implements tools for developers to observe exactly how long a controller algorithm takes to run. This helps the developer choose a frequency fast enough to maintain robot balance within the computer's capabilities.
70

Design and development of a low cost heart best monitor device using finger photoplethysmography technique :|bcircuit design and fabrication of a non-invasive heart beat monitoring device that employs reflectance and transmission mode photoplethysmography using parallel port interface and microcontroller PIC16F84A.

Ramli, Nur Ilyani Binti January 2014 (has links)
A low cost Heart Beat Monitoring device (HBMD) for detecting heart beat in beats per minute is presented in this thesis. An optical technique called “Photoplethysmography” is utilized by attaching to the base of the finger for monitoring beat to beat pulsation. Two major design issues addressed in this research is to achieve a strong and accurate PPG signal and simultaneously minimizing physiological artefacts and interference. In order to achieve the aim and objectives of the research, this thesis thoroughly explores two new signal conditioning hardware designs. Firstly is the design and fabrication of a low cost reflectance mode PPG heart monitor using parallel port interfacing and secondly are the design and development of a portable transmission mode PPG heart monitor using microcontroller PIC16F84A and PIC16F87. Both PPG heart monitor design is divided into three phases. First is the detection of weak pulses through the fingertip. The PPG signal is then amplified, filtered and digitized by the signal processing unit. Finally the heart rate is calculated, analyzed and displayed on the computer using parallel port interface and on the liquid crystal display using microcontroller PIC16F87. A comprehensive circuit design and analysis work was implemented verified by Proteus VSM circuit simulations and laboratory experiments. Data is presented from the method comparison study in which heart rates measured with the reflectance mode PPG and portable transmission mode PPG heart monitor were compared with those measured with standard techniques on 13 human subjects. Benchmarking tests with approved pulse oximeter and blood pressure monitor Omron M6 reveals that the PPG heart monitor is comparable to those devices in displaying the heart rate. It is also verified through experiments that both PPG heart monitor design fulfill the objectives, including achieving strong and accurate PPG signal, reduction in physiological artefacts and interference and financially low in cost. As the conclusion, the current version of the reflectance mode PPG and portable transmission mode PPG heart monitor successfully measure heart rates fast and reliably in most subjects in different body position. The PPG heart monitor proposed avoid the need to apply electrodes or other sensors in the correct position which directly minimizes the preparation time drastically. This makes the PPG heart monitor more attractive for heart monitoring purpose and its advantage should be explored further. / Ministry of Higher Education Malaysia (MOHE) and Universiti Tun Hussein Onn Malaysia (UTHM)

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