Power supply in any electronic system is a crucial necessity. Especially so in fully compliant personalized advanced healthcare electronic self-powered systems where we envision seamless integration of sensors and actuators with data management components in a single freeform platform to augment the quality of our healthcare, smart living and sustainable future. However, the status-quo energy storage (battery) options require packaging to protect the indwelling toxic materials against harsh physiological environment and vice versa, compromising its mechanical flexibility, conformability and wearability at the highest electrochemical performance. Therefore, clean and safe energy storage solutions for wearable and implantable electronics are needed to replace the commercially used unsafe lithium-ion batteries. This dissertation discusses a highly manufacturable integration strategy for a free-form lithium-ion battery towards a genuine mechanically compliant wearable system. We sequentially start with the optimization process for the preparation of all solid-state material comprising a ‘’Lithium-free’’ lithium-ion microbattery with a focus on thin film texture optimization of the cathode material. State of the art complementary metal oxide semiconductor technology was used for the thin film based battery. Additionally, this thesis reports successful development of a transfer-less scheme for a flexible battery with small footprint and free form factor in a high yield production process. The reliable process for the flexible lithium-ion battery achieves an enhanced energy density by three orders of magnitude compared to the available rigid ones. Interconnection and bonding procedures of the developed batteries are discussed for a reliable back end of line process flexible, stretchable and stackable modules. Special attention is paid to the advanced bonding, handling and packaging strategies of flexible batteries towards system-level applications. Finally, this work shows seamless integration of the developed battery module in an effective strategy to incorporate them into a complex architecture such as orthodontic domain in the human body. The developed optoelectronic system embedded in a 3D printed smart dental braces for enhanced enamel healthcare protection and overall healthcare cost reduction. These findings complement and provide power solution options in which flexibility of electronics is an added beneficial dimensionality to wearable biomedical and implantable devices.

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Advancements in electronics research triggered a vision of a more connected world, touching new unprecedented fields to improve the quality of our lives. This vision has been fueled by electronic giants showcasing flexible displays for the first time in consumer electronics symposiums. Since then, the scientific and research communities partook on exploring possibilities for making flexible electronics. Decades of research have revealed many routes to flexible electronics, lots of opportunities and challenges. In this work, we focus on our contributions towards realizing a complimentary approach to flexible inorganic high performance electronic memories on silicon. This approach provides a straight forward method for capitalizing on the existing well-established semiconductor infrastructure, standard processes and procedures, and collective knowledge. Ultimately, we focus on understanding the reliability and functionality anomalies in flexible electronics and flexible solid state memory built using the flexible silicon platform. The results of the presented studies show that: (i) flexible devices fabricated using etch-protect-release approach (with trenches included in the active area) exhibit ~19% lower safe operating voltage compared to their bulk counterparts, (ii) they can withstand prolonged bending duration (static stress) but are prone to failure under dynamic stress as in repeated bending and re-flattening, (iii) flexible 3D FinFETs exhibit ~10% variation in key properties when exposed to out-of-plane bending stress and out-of-plane stress does not resemble the well-studied in-plane stress used in strain engineering, (iv) resistive memories can be achieved on flexible silicon and their basic resistive property is preserved but other memory functionalities (retention, endurance, speed, memory window) requires further investigations, (v) flexible silicon based PZT ferroelectric capacitors exhibit record polarization, capacitance, and endurance (1 billion write-erase cycles) values for flexible FeRAMs, uncompromised retention ability under varying dynamic stress, and a minimum bending radius of 5 mm, and (vi) the combined effect of 225 °C, 260 MPa tensile stress, 55% humidity under ambient conditions (21% oxygen), led to 48% reduction in switching coercive fields, 45% reduction in remnant polarization, an expected increase of 22% in relative permittivity and normalized capacitance, and reduced memory window (20% difference between switching and non-switching currents at 225 °C).

Master of Science

The Flexible Manufacturing Cell (FMC) represents an important and widely utilized constituent of hierarchically structured automated manufacturing systems. The control of FMCs is therefore of great importance in automated manufacturing. However, there are few tools and methodologies available for specifying and developing the control logic. The few tools that do exist have proven to be impractical due to their equirements for compatibility by the constituent equipment. Therefore, this research focuses on the development of a solution to the control of FMCs through the development of a programming language that provides a methodology and capabilities for developing the supervisory control applications. Accordingly, a programming language was developed in which the control logic is specified in modules, each of which control an equipment or resource in the cell. These modules interact with each other according to well defined models of interaction to achieve the control. The language provides features to enable this modularity and the interaction between the modules. The process plan of the parts that are produced in the cell drive the control logic and are also the means of communication between the modules. Additionally, several features required for control such as the detection of deadlocks, part information and so on are also developed. In the proposed language, the communication problem is separated from the logic specification. Guidelines and requirements are developed for a language implementation system that will enable the communication with the cell devices and that works with the language structure. / Master of Engineering

Many real-world vehicle routing problems are dynamic optimization problems, with customer requests arriving over time, requiring a repeated reoptimization. In this paper, we consider a dynamic vehicle routing problem where one additional customer arrives at a beforehand unknown location when the vehicles are already under way. Our objective is to maximize the probability that the additional customer can be integrated into one of the otherwise fixed tours without violating time constraints. This is achieved by letting the vehicles wait at suitable locations during their tours, thus influencing the position of the vehicles at the time when the new customer arrives. For the cases of one and two vehicles, we derive theoretical results about the best waiting strategies. The general problem is shown to be NP-complete. Several deterministic waiting strategies and an evolutionary algorithm to optimize the waiting strategy are proposed and compared empirically. It is demonstrated that a proper waiting strategy can significantly increase the probability of being able to service the additional customer, at the same time reducing the average detour to serve that customer.

The Fourth Industrial Revolution is driven by cyber-physical systems, in which sensors link the real and virtual worlds. A global explosion of physical sensors seamlessly connected to networks is expected to produce trillions of sensors annually. To accommodate sustainable sensor production, it is crucial to minimize the consumption of raw materials, the complexity of fabrication, and waste discharge while improving sensor performance and wearability. Graphene has emerged as an excellent candidate material for its electrical and mechanical characteristics; however, its economic impact has been hindered by complex and energy-intensive processes. Meanwhile, printed electronics offer a compelling range of merits for scalable, high-yield, low-cost manufacturing of graphene. Among them, the one-step laser scribing process has enabled a simultaneous formation and patterning of porous graphene in a solid-state and opened new perspectives for versatile and widely tunable physical sensing platforms. This dissertation introduces flexible, lightweight, and robust Laser-Scribed Graphene sensor solutions for detecting various physical parameters, such as strain, flow, deflection, force, pressure, temperature, conductivity, and magnetic field. Multifunctionality was obtained by exploiting the direct laser scribing process combined with the flexible nature of polyimide and the piezoresistivity of porous graphene. The outstanding properties of LSG, such as low cytotoxicity, biocompatibility, corrosion resistance, and ability to function under extreme pressure and temperature conditions, allowed targeting diverse emerging applications. As a wearable device in healthcare, the LSG sensor was utilized to monitor motions involving joint bandings, such as finger folding, knee-related movements, microsleep detection, heart rate monitoring, and plantar pressure measurements. The marine ecosystem was used as an illustrative sensor application to cope with harsh environments. To this end, the sensor measured the velocity of underwater currents, pressure, salinity, and temperature while monitoring the movement of marine animals. The sensitivity to the magnetic field remained stable up to 400 °C, making the LSG sensor a viable option for high-temperature applications. In robotics, the LSG sensor was developed for velocity profile monitoring of drones and as a soft tactile sensor. The study provides insights into methods of improving sensor performance, opportunities, and challenges facing a tangible realization of LSG physical sensors.

Compliant electronics are an emerging class of electronics which offer physical flexibility in their structure. Such mechanical flexibility opens up opportunities for wide ranging applications. Nonetheless, compliant electronics which can be functional in unusual environments are yet to be explored. Unusual environment can constitute a harsh environment where temperature and/or pressure is much higher or lower than the usual room temperature and/or pressure. Unusual environment can be an aquatic environment, such as ocean/sea/river/pond, industrial processing related liquid and bodily fluid environment, external or internal for implantable electronics. Finally, unusual environment can also be conditions when extreme physical deformation is anomalously applied to compliant electronics in order to understand their performance and reliability under such extraordinary mechanical deformations. Therefore, in this thesis, three different aspects of compliant electronics are thoroughly studied, addressing challenges of material selection/optimization for unusual environment applications, focusing on electrical performance and mechanical flexible behavior. In the first part, performance of silicon-based high-performance complementary metal oxide semiconductor (CMOS) devices are studied under severe mechanical deformation. Next, a high-volume manufacturing compatible solution is offered to reduce the usage of toxic chemicals in semiconductor device fabrication. To accomplish this, Germanium Dioxide (GeO2) is simultaneously used as transient material and dielectric layer to realize a dissolvable/bioresorbable transient electronic system which can be potentially used for implantable electronics. Finally, wide bandgap semiconductor Gallium Nitride is studied to understand its mechanical flexibility under high temperature conditions. In summary, this research contributes to the advancement of material selection, optimization and process development towards achieving compliant and transient devices for novel applications in unusual environments.

Real-time monitoring of fluid properties in tubular systems, such as viscosity, flow rate, and pressure, is essential for industries utilizing the liquid medium. Today such fluid characteristics are studied off-line using laboratory facilities that can provide accurate results. Nonetheless, it is inadequate to match the pace demanded by the industries. Therefore, off-line measurements are slow and ineffective. On the other hand, commercially available real-time monitoring sensors for fluid properties are generally large and bulky, generating considerable pressure reduction and energy loss in tubular systems. Furthermore, they produce significant and persistent damage to the tubular systems during the installation process because of their bulkiness. To address these challenges, industries have realigned their attention on non-destructive testing and noninvasive methodologies installed on the outer tubular surface to avoid flow disturbance and shutting systems for installations. Although, such monitoring sensors showed greater performance in monitoring and inspecting pipe health conditions, they are not effective for monitoring the properties of the fluids. It is limited to flowmeter applications and does not include fluid characteristics such as viscometers. Therefore, developing a convenient real-time integrated sensory system for monitoring different fluid properties in a tubular system is critical. In this dissertation, a fully compliant compact sensory system is designed, developed, examined and optimized for monitoring fluid properties in tubular architectures. The proposed sensor system consists of a physically flexible platform connected to the inner surface of tubes to adopt the different diameters and curvature shapes with unnoticeable flow disruption. Also, it utilizes the microchannel bridge to serve in the macro application inside pipe systems. It has an array of pressure sensors located bellow the microchannel as the primary measurement unit for the device. The dissertation is supported by simulation and modeling for a deeper understanding of the system behavior. In the last stage, the sensory module is integrated with electronics for a fully compliant stand-alone system.

This thesis describes the experimental test results and computer simulation investigations which were conducted to verify the existing theory of skewed disk forced response predictions. The experimental tests were conducted on a horizontal flexible shaft rotor system supported in two hydrodynamic journal bearings. The computer simulations were conducted with a program that uses a matrix transfer method to get the desired solution. The agreement between experiment and simulation is very good for most skewed disk response characteristics. The influence of measurement errors and operation condition uncertainties are discussed.In the first part of this study, the dynamic behavior of experimental investigations focused on two different skewed disk designs which were mounted at midspan, 1/3 span and 2/3 span of the shaft. The two skewed disks were designed to allow a fine angle adjustment of the desired skew angle. The two designs are (a) the angle tiltable disk and (b) the couple unbalanced mass disk. The experimental results are shown to be close to the theoretical predictions of other authors.In the second part of this study, an existing computer program was used to simulate the experimental test rotor. The results give excellent qualitative agreement although there are some differences in quantitative analysis comparisons. The forced response characteristics of the computer simulation match the experimental results. It has been shown that by using the approximate linear skewed disk model, it is possible to get similar results to the experimental tests for similar disk skew conditions. / Master of Science