Engineering Science - Theses, Dissertations, and other Required Graduate Degree Essays

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Screen-printable polymer fabrication with applications to wearable nanocomposite electronics and microfluidic systems

Author: 
Date created: 
2018-09-19
Abstract: 

Wearable devices and systems are already important to our lives and have the potential for even greater impact. Many researchers are developing wearable devices and systems, and many different technologies are investigated. However, most of these technologies have limitations in flexibility, long fabrication times, lack of reusability, or complicated attachment mechanisms. Furthermore, many systems are limited in the functions that they can perform. Most systems are also confined to electronic functionality; there is not a fully successful wearable microfluidic technology developed with wearable fluidic channels for microfluidic devices, e.g., foldable microfluidic mixers or flexible bio-fluid sensors for wearable analysis systems. As an alternative approach, we develop new methods to screen-print electronic and fluidic devices on clothing that employ materials designed specifically for printing on textile. We present a new screen-printable silver conductive nanoparticle composite polymer (C-NCP) that can be applied to wearable systems for electronic functionality. We also develop a new technique to realize fully wearable microfluidic devices. Screen printable C-NCPs benefit the development of wearable devices due to their high degree of flexibility, good conductivity, and ability to be easily patterned into electrical and microfluidic devices. The new microfluidic device fabrication method enables easy, simple, and fast development of wearable microfluidic devices using inexpensive materials and equipment. In this thesis, a screen-printable C-NCP is developed and characterized, and its potential for wearable devices and systems is explored through a variety of demonstrator systems. The new microfluidic device fabrication method is explained in detail with optimization and characterization. Passive wearable microfluidic devices are fabricated on fabric, and active wearable microfluidic devices with electrical structures are also fabricated by combining wearable microfluidic structures with silver C-NCP as electronic routing and electrodes. The following demonstration devices and systems are developed to showcase different aspects of the new materials and fabrication techniques: 1) flexible dry electrocardiogram (ECG) electrodes screen printed on textile to measure heart bioelectrical signals; 2) flexible electrical routing printed on a safety vests for LED attachment and lighting system demonstration; 3) wearable microfluidic mixer fabricated on textiles; 4) and a wearable fluid conductivity sensor that combines C-NCP with flexible microfluidics.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Bonnie L. Gray
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) Ph.D.

Multi-phase placement approach for field programmable gate arrays

Author: 
Date created: 
2018-06-29
Abstract: 

Field Programmable Gate Arrays (FPGAs) are integrated circuits that contain configurable logic blocks and wiring resources that enable them to implement digital circuits. To create a design, the designer typically describes the design using a Hardware Description Language (HDL). This HDL is synthesized into a configuration bitstream to program the FPGA using Computer-Aided Design (CAD) tools. Due to their rapid growth in size, FPGAs are able to implement increasingly larger circuit designs. However, this has also lead to the run-time of the CAD tools increasing dramatically. To improve the run-time of CAD tools, this thesis focuses on improving the run-time of the placement stage of the CAD algorithms, which accounts for a significant portion of the overall run-time of the CAD flow. This thesis explores techniques for creating design specific groupings of logic blocks (called multi-blocks) that can be used in conjunction with a new placement algorithm, called the singularity placer. This approach allows the flow to collapse related logic blocks in the design into “multi-blocks”, thereby reducing the design complexity for placement. This reduced complexity can be used to reduce placement runtime, despite having to re-expand these multi-blocks into their original logic blocks to complete the placement phase of the design. This approach allows tradeoffs between the run-time of the CAD tools and the design’s key performance metrics (e.g. operating frequency). This thesis first proposes and evaluates a number of algorithms to divide a design comprised of logic blocks into groups of logic blocks (also known as “multi-blocks”). The objective of this approach is to reduce the run-time as grouping logic blocks of a design decreases the number of nodes to be processed for placement. Next, a two-phase placement algorithm, called the singularity placer, is proposed that can place a mix of multi-blocks and singular logic blocks onto FPGA resources. The experimental evaluation shows that the proposed approach to placement enables up to 30X speedup with an average wirelength degradation of 12% with respect to VPR. This speedup is a dramatic increase that has the potential to make FPGA devices and design flows more useful to application spaces that desire acceleration over pure software in a timely fashion, while not requiring the “best” operating frequency possible.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Lesley Shannon
Peter Jamieson
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) Ph.D.

Fabrication of two dimensional MoS2 sensors for piezoelectric applications

Author: 
Date created: 
2018-08-21
Abstract: 

With the growing popularity of miniaturization of high performance piezoelectric devices, the research on applications of Transition Metal Dicalcogenide (TMD) mono layers has also grown a lot. This is because of the suitable piezoelectric properties exhibited by these two dimensional materials. In this project, a piezoelectric sensor, which could be used for various applications, is being designed which could receive both low and high frequency signals well. This project is in collaboration with Think Sensor Research, an organization working towards the development of marine and aerospace sensor applications. The present version of this device, which is being used by the collaboration company, possesses Lead zirconate titanate (PZT) as the piezoelectric material. Our purpose was to design and fabricate this device using Molybdenum Disulfide (MoS2) instead of PZT and observe the response and piezoelectric properties of the device.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Michael Adachi
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Project) M.Eng.

Application of machine learning techniques for detecting anomalies in communication networks

Author: 
Date created: 
2018-06-19
Abstract: 

Detecting, analyzing, and defending against cyber threats is an important topic in cyber security. Applying machine learning techniques to detect such threats has received considerable attention in research literature. Anomalies of Border Gateway Protocol (BGP) affect network operations and their detection is of interest to researchers and practitioners. In this Thesis, we describe main properties of the BGP and datasets that contain BGP records collected from various public and private domain repositories such as Réseaux IP Européens (RIPE) and BCNET. With the development of fast computing platforms, the neural network-based algorithms have proved useful in detecting BGP anomalies. We apply the Long Short-Term Memory machine learning technique for classification of known network anomalies. The models are trained and tested on various collected datasets. Various classification techniques and approaches are compared based on accuracy and F-Score.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Ljiljana Trajković
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) M.A.Sc.

Feasibility of using force myography (FMG) for estimating hand force and wrist torque

Date created: 
2017-10-12
Abstract: 

Hand force estimation is critical for applications that involve physical human-machine interactions for force monitoring and machine control. Force Myography (FMG) is a potential technique to be used for estimating hand force/torque. The FMG signals represent the volumetric changes in the arm muscles due to muscle contraction or expansion during force/torque exertion. The aim of this thesis is to explore the suitability of FMG for hand force/torque estimation. Studying the feasibility of using FMG for torque estimation was preliminary investigated by using 1-DOF torque sensor for labeling the FMG during torque exertion. A custom designed force-sensing resistors (FSRs) band was donned on the forearm for measuring FMG signals, while the participants exerted torque around three axes. A regression model was created for each torque axis. The average R2 was 0.89 for pronation-supination, flexion-extension, and radial-ulnar deviations. Using 1-DOF torque sensor for labeling the data needs a new custom-rig for capturing each torque axis. To overcome this limitation, a 6-DOF force/torque load cell was used for labeling the FMG data during force/torque exertion in any direction. In addition, 60 FSRs were embedded into four bands to be worn on the arm for measuring FMG signals during force/torque exertion. Healthy participants were recruited in this study and were asked to exert isometric force along three perpendicular axes, torque about the same three axes, and force and torque freely in any direction. Three cases were considered to explore the performance of the FMG bands in estimating force/torque in single- and multi- axis. These cases are: (1) 6 axes force/torque individually; (2) 3-DOF force and 3-DOF torque; and (3) 6-DOF force and torque simultaneously. In addition, a comparison between all possible combinations of the four bands was held to provide guidelines about the best placement of the FMG measurements in each case. The results show a promising potential of FMG to estimate isometric force/torque. Specifically, the average R2 accuracies using the four bands on the arm are 0.97 when the 6 force/torque axes were considered individually; 0.98 and 0.96 for the 3-DOF force and torque, respectively; and 0.95 for 6-DOF force/torque estimation.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Carlo Menon
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) M.A.Sc.

Voluntary Driven, Velocity Controlled Tremor Suppression

Author: 
Date created: 
2017-12-15
Abstract: 

The standard course of treatment for pathological tremor mainly involvespharmacotherapy. However, treatment can be challenging as individual responses totherapy vary widely. Individuals with a disabling or medication refractory tremor, mayhave the option for one of several surgical procedures. Essential Tremor (ET) andParkinson’s Disease (PD) are considered to be among the most pervasive of tremorrelated disorders. Overall pathological tremor prevalence statistics range from 2% to wellover 10% in the elderly. Up to 60% of those affected by tremor experience disability intheir Activities of Daily Living (ADL) and more than a quarter struggle to find reliefthrough conventional treatments. There is, therefore, a persuasive case for alternativetherapies for individuals with pathological tremor. This thesis proposes a tremorsuppression approach to track the intentional motion. Typically tremor suppressionmethods estimate the tremor component and produce a counteracting signal. Thesuggested approach instead predicts the voluntary motion component via forceinformation, while the tremor signal is regarded as a motion disturbance andconsequently rejected. The approach is demonstrated in a modular form for flexibility inimplementation. The suppression approach, involving an admittance and speedcontrolled feedbacks, was evaluated experimentally with a benchtop tremor simulationsystem. Parametric stability and controller tuning were demonstrated, and response timeperformance specifications were achieved. Spectral analysis results show a 99.8%tremor power reduction; the power reduction related to the voluntary movement wasinstead negligible (0.18%). A robotic orthosis was subsequently developed to validatethe approach for the suppression of pathologic elbow tremor. Two types of roboticallysimulated human inputs were evaluated in addition to employing orthosis gravitycompensation. Finally, nine participants with either ET or PD were recruited andperformed computerized pursuit tracking tasks with the orthosis. The mean tremor powerreduction was 94.4%; significantly higher than typically achieved with pharmacotherapy.Importantly, the effect to the voluntary motion was limited to only 6.6%. Whenmechanically suppressing tremor, there is a risk of preventing the individual with tremorfrom performing volitional movements. An important contribution of this work involves theexplicit treatment of the impact to the volitional motion.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Carlo Menon
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) Ph.D.

Hand Gesture Identification in Older Adults using Force-Myography

Author: 
Date created: 
2017-06-20
Abstract: 

The projected increase in the proportion of seniors in society has prompted the growth of senior-technologies that support aging-in-place. The aim of this thesis to explore the suitability of Force Myography (FMG) for hand gesture identification in aging populations to complement other technologies that promote aging-in-place and to investigate the practical considerations for implementation. Characteristics of using FMG with seniors (aged 60+ years old) was first determined with a protocol involving five seniors and five non-seniors. Participants were invited to don a custom FMG device and perform a series of stationary hand gestures while being guided by a virtual user interface. The interface provided online image instructions of the required gesture, as well as visual feedback of successful gesture identification. Participants also performed household activities based tasks in a self-selected manner. On average, seniors completed specified hand gestures within 1.4 seconds of online instruction, with inadvertent identification of control gestures during household tasks lasting at most 1.45 seconds. Although these times were comparable non-senior participants, seniors demonstrated increased variability. Lastly, online accuracies for gesture classification only reached 75% compared to the 91% of non-senior participants. Considering the results of the first study, a follow up study was performed with a larger recruitment pool focusing on intrinsic user features that influence the variability in FMG acquisition and modelling. The results demonstrate that age and gender associated differences in band tightness, grip strength and ratio of skinfold thickness to forearm circumference account for at most 30% of the variability in FMG responsiveness, translating to 7% to 30% of the variability of model test accuracy. Intrinsic user features also influenced the severity that functional noise (the affect of unintended movements) had on classification. Results also revealed that variables independent of the user, such as band removal, contribute significantly to declines in testing accuracy, where declines ranged from 28% to 96%. Finally, results also showed that methods of FMG modelling typically encountered in the literature shows limited effectiveness during non-static activity.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Carlo Menon
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) M.A.Sc.

Towards the development of a sub 500 micron thermally actuated scanning fiber endoscope for detection of lung cancer

Date created: 
2018-05-30
Abstract: 

Medical professionals increasingly rely on endoscopes to carry out many minimally-invasive procedures on patients in order to safely examine, diagnose and treat a myriad of conditions. However, their distal tip size dictates which passages of the body they can be inserted into and consequently what organs they can access. For inaccessible areas and organs, patients are often subjected to intrusive, risky and uncomfortable procedures; diagnosis of lung cancer is one of these cases. Hence, this study sets out to design an endoscope head that has an outer diameter of less than 500 microns, small enough to be inserted into the lungs. To attain this goal, a novel approach based on resonance thermal excitation of a dual clad single mode optical fiber at a location close to its base is proposed. The previously obtained analytical models for describing the lateral vibratory motion of the fixed-free micro-cantilever are used to validate the corresponding physical prototypes. Parameters such as choice of materials, resonance frequency, bonding methods, shape and dimensions of the actuator bridge, structural rigidity, assembly are considered in the physical design of the device. Lateral free-end deflection of the center fiber is used as a benchmark for evaluating performance. The results show that this novel proposal can be used to satisfy the project requirements.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Carlo Menon
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) M.A.Sc.

An in-depth study on Power Line Communications

Author: 
Date created: 
2018-04-13
Abstract: 

Power Line Communication has acquired tremendous interest from the research community since its applications and development in the field of Smart grid, in-home & vehicular communication, and its role in Internet of Things (IoT). In this project, I study the features of power line communication and provide an overview of applications in both narrowband and broadband systems, listing applicable standards and specifications. We study the problems in the technology and how recent developments have led to resolve them. A number of tests were conducted for the in-home Power Line Communication (PLC) setup, and different PLC modules were tested for a variety of wiring systems. Further, we conducted tests on two transformers to list the frequencies that can pass through the system, and to study general behaviour of the system to high frequencies.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Ash M. Parameswaran
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Project) M.Eng.

Development of a motion vector field model of an unstable slope using terrestrial radar interferometry

Date created: 
2018-04-20
Abstract: 

200 kilometres southeast by south of Fairbanks, Alaska lies the Fels Glacier valley where within, several sections of the northern slope are experiencing active deep-seated gravitational slope deformation. High-temporal resolution terrestrial radar imagery of the westernmost such section was acquired over the course of a 3-day field campaign in July 2017. These data were analyzed using interferometric techniques with the goal of extracting the rate of deformation across the 3-kilometre-wide section. The analysis and resulting motion vector field model reveal the extent and relative magnitude of the most actively deforming region located at the base of the slope with respect to the main body of the slope as observed over the short duration of the campaign.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Bernhard Rabus
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Project) M.Eng.