Currently, the Low Earth Orbit (LEO) space environment contains a growing number of orbital debris objects. This growing orbital debris population increases collision probabilities between both orbital debris and functioning satellites. A phenomenon known as Kessler Syndrome can be induced if these collisions occur. Kessler Syndrome states that these collisions can lead to an exponential increase in the orbital debris population, which could dangerously impede future space missions. Current literature outlines the necessity of stabilizing the near-Earth environment debris population and introduces the concept of active debris removal (ADR). The use of ADR on five orbital debris objects per year was found to be a requirement to achieve stability within the orbital debris population. A viable mission architecture is henceforth explored to utilize ADR for near-future execution to further develop research for orbital debris mitigation missions. The larger orbital debris objects are found in many different orbital regimes and are primarily composed of spent rocket bodies and retired satellites. Different orbital debris ranking schemes have been developed based on the population density in these different regimes, which are linked to higher collision probabilities. Using these ranking schemes, a set of target objects are selected to be investigated for this mission design that was composed of target objects with similar orbital characteristics that were not launched by the Commonwealth of Independent States (CIS) to minimize legal barriers. Different ADR capture and removal methods are inspected to find the optimal methods for this mission. An Analytical Hierarchy Process (AHP) has been used to assess these different methods, which utilizes comparisons of the different methods among a set of weighted criteria. A net capture method with a low thrust chemical engine for removal is identified as the optimal ADR method. The use of a laser detumbling system is also selected to stabilize target objects with a high rotation rate. A rendezvous and deorbit orbital analysis are conducted using both a low fidelity tool (for preliminary results) and a high fidelity tool (for more precise results). The rendezvous analysis is used to select a mission architecture that was composed of two different chaser satellites which rendezvous with the five different target objects by taking advantage of nodal precession. The deorbit analysis investigates different decay timelines and found the delta-v estimates that would be required to deorbit the target objects within the same year that they were captured in. These two orbital analyses provide valuable insight to the mission timeline, delta-v estimates, and approximate mass requirement for the chaser satellite and deorbit kits. The results of the target selection process, ADR selection process, and the rendezvous and deorbit analyses are meant to provide an initial concept and analysis for a near-future ADR mission. These approximate results provide insight and information to further develop orbital debris mitigation research to help solve the orbital debris population growth challenge for future space missions. / Master of Science / Currently, the near Earth space environment contains a growing number of space debris. This growth in the orbital debris population increases the likelihood of collisions with orbital debris, functioning satellites, and launch vehicles. These collisions can generate a chain of events that could exponentially increase the population of orbital debris, which at some scale could become a major obstacle for future space missions. Researchers have introduced the concept of active debris removal (ADR), which in simulations has been shown to help stabilize the growth of orbital debris. The use of ADR to remove as low as five orbital debris objects per year has been found to be sufficient to stabilize debris growth. A viable mission architecture using ADR technologies that can be implemented in the near future is henceforth explored to further develop research for orbital debris missions. The larger orbital debris objects are found in many different areas in space and are primarily made up of used rocket bodies and retired satellites. Different ranking schemes have been developed by researchers for these larger orbital debris objects based on the population density within these areas in space, which are linked to the chance of a collision. Using these ranking schemes, a set of orbital debris objects are selected to be targeted for this mission design. This set of selected target objects have similar orbital characteristics and the political/legal barriers that could be present during removal are minimal. An ADR mission is composed of two primary components, a capture method and a removal method, which are inspected to find the optimal methods for this mission. A decision-making technique, called an Analytical Hierarchy Process (AHP), has been used to assess these different methods. The AHP compares different capture and removal methods using a set of weighted criteria. A net capture method with small thrusters for removal is identified as the optimal ADR method. Additionally, the use of a laser system is selected to stabilize target objects that may be rotating too quickly for capture. An analysis on different mission architectures is conducted using both a low fidelity tool (for preliminary results) and a high fidelity tool (for more precise results). A mission architecture composed of two different "chaser" satellites which rendezvous with and deorbit the five different target objects is selected. The analysis used on the selected mission architecture provides valuable insight to the mission timeline, fuel estimates, and approximate mass requirements. The results of the target selection process, ADR selection process, and the mission architecture analysis are meant to provide an initial concept and introduce possible requirements for a nearfuture ADR mission. These approximate results provide information to further develop research that can help us solve the orbital debris population growth challenge for future space missions.

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The complexity of automotive software has increased dramatically in recent years. New technological advances as well as increasing market competitiveness create a high cost-pressure environment. This thesis seeks to apply established modular principles to a Simulink Model to increase information hiding to improve the maintainability of controls software. A Hybrid Supervisory Controller (HSC) model, developed as part of the McMaster EcoCAR Competition, is used throughout this thesis. The software design process followed during the HSC model development is detailed, as well as providing an example of the application of the Simulink Module Tool, a Simulink add-on developed by Jaskolka et. al. The HSC System decomposition was restructured based on an analysis of the likely changes to the vehicle software, as well the system secrets contained within the model. This thesis also presents an analysis of the original and modular system decompositions, comparing several common software indicators of information hiding, coupling, cohesion, complexity, and testability. The modular decomposition led to a significant improvement in information hiding, both in system changeability and internal implementation. Likely changes to the system propagate to fewer modules and components within the new decomposition, with hardware data separated from behavioral algorithms, and all modules grouped based on shared secrets. The redistribution of algorithms based on separation of concern also led to improvements in coupling, cohesion, and interface complexity. The resulting software design process and modular system decomposition provides a framework for future EcoCAR students to focus on correct design and implementation of hybrid vehicle software. The benefits provided by the application of the Simulink Module Tool also contributes additional data and supporting evidence to the improvements that can be realized within Simulink Models by introducing the concepts of information hiding and modularity. / Thesis / Master of Applied Science (MASc) / The complexity of automotive software has increased dramatically in recent years. New technological advances as well as increasing market competitiveness create a high cost-pressure environment. As a result, improving the development of automotive software and its maintainability has become an increasingly critical issue to solve. This thesis uses a Hybrid Vehicle Controller Model developed within MATLAB Simulink to investigate the possible improvements that can be made to software modularity. The system decomposition is modified using the Simulink Module Tool, and is analyzed regarding improvements to information hiding, interface complexity, and specifically minimizing change propagation. The modular improvements made to the Simulink Model resulted in significant improvements in system changeability and information hiding, providing a useful framework for future EcoCAR students.

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As distributed generations and renewable energy are becoming the fastest growing segment of the energy industry, the technical issues and environmental impacts have to be studied and understood. The large number of small-scale Microgrid components with their own characteristics is a big challenge for Microgrid modeling, simulation, planning and operation. The major goal of this thesis is to build a library of various Microgrid components. First of all, the thesis is going to present a detailed description of Microgrid models with moderate complexity. Next, it will present the modeling of loads, utility grid and transmission lines. Then, the paper will discuss the distributed generation models that have been developed in Matlab/Simulink including Diesel Engine, Fuel Cell, Micro Gas Turbine, Wind Turbine, Photovoltaic Cell, along with the detailed modeling of short-term storage (Battery, Pumped Hydro Storage, Flywheel, and Supercapacitor). In addition to steady-state study, the thesis will also discuss the hybrid sample systems that are built to investigate their transient responses. To enhance the simulation performance, some improvements on modeling and simulation will be introduced as well. To accommodate the high demand of renewable energy and the environment policy, the planning and operation the of Micro-source generators has been studied using HOMER. Simulation results show a case study of an optimal microgrid configuration on Ontario area in Canada. Sensitivity variables are specified to examine the effect of uncertainties, especially in a long-term planning. Also, demand side management plays an important role in the operation of Microgrid. Based on raw data, case studies are carried out to investigate and validate the demand response methods. Finally, the philosophy for Microgrid protection, especially Time-delay overcurrent protection, will be briefly introduced in both gird-connected and islanding modes. / Master of Science

Many industries are turning to wireless communication systems to track their assets. One example of such an industry is the shipping industry, where — under the growing emphasis on homeland security — tracking cargo containers and their contents has become a high priority. There are several beacons on the commercial market that will meet this need if the required beacon does not need to be independently powered or to have global coverage. This thesis attempts to find a design solution for a beacon that transmits location data, is battery powered, and has world-wide coverage. The beacon is intended to be a low power, transmit only device, and the receiver will not be designed to operate in real-time. Several communication systems were evaluated on these conditions, and the Globalstar Satellite System was selected to use as the communication system for the beacon. The Globalstar Satellite System is a low earth orbiting (LEO) satellite system and uses Code Division Multiple Access (CDMA) to allocate system resources to the maximum number of users possible. Discussions of spread spectrum techniques and theory, Rake receivers, and error correction codes are included as a background for the design. This thesis examines the initial steps in the design of the transmitter beacon and aims to determine the minimum required beacon transmit power for good receiver performance. A portion of the correlator in the Globalstar receiver is simulated for several scenarios: a single user case with varying transmit power, and a multiple user case with fixed transmit power. Although not likely to occur, the single user case was used to baseline system performance and to verify the multi-user case results. The simulated correlator employed a parallel search strategy and used a truncated version of the Globalstar system code sequence. Finally, a threshold analysis was performed to determine if better receiver performance could be obtained. / Master of Science

The tire–terrain interaction is an essential criterion for assessing tire performance. Understanding the complex characteristics of the dynamic interactions of tires and terrain required a detailed and deep study on the characteristics of the contact patch area of the tire. Most of the studies conducted to determine the properties of the contact patch considered the tire-road interaction in a static condition and there are a limited number of research studies that focused on the dynamic behavior of the tire at the contact area especially when the real-time measurement of the dynamic contact area of the rolling tire with high slip ratio is the matter of interest. In order to completely understand the tire dynamics at the contact patch, a novel optical method based on light refraction and reflection is proposed for the measurement of contact area between the tread of the tire and a rigid transparent surface. To this end, constructing an indoor test rig is required. In this research, a three-dimensional drawing software Autodesk Inventor has been used to analyze a customized testing facility. An indoor test rig has been designed and manufactured to visualize the contact area of a rolling tire. A supporting mechanical system incorporated into this test rig allows providing the tire with variable camber angles and slip ratios. For the rolling tire, a digital camera GoPro has been used under a glass panel to record the tread pattern in detail when the tire passes over it during the test, to represent the footprint for a high slip ratio. From the image obtained with this system, the length, width, ratio, and shape of the patch can be determined, which are related to the effect on tire traction performance. This study specifically proposes a digital image correlation technology that can be used to capture the contact patch of a passenger car tire 205/55R16 and to obtain the geometry features of the contact area. Based on the appropriate image processing techniques in the MATLAB, a precise reconstruction of tire footprint was realized. The results for the footprint properties of the tire with an applied normal load of 4 kN and tire inflation pressures of 21 Psi for free rolling, static state, and the slip ratio of 0%, 2%, 4%, 6%, 8%, 10%, 12%, 15%, 20%, 25%, 30%, and 35% are presented. Presented results in the paper will show that the system is robust enough to obtain a real-time dynamic measurement. The novel method based on digital image processing revealed by the author can be validated as a precision measurement system of footprint characteristics. / Master of Science / The tire–road interaction is an essential criterion for assessing tire performance. Most of the studies conducted to determine the properties of the contact area considered the tire-road interaction in a static condition and there are a limited number of research studies that focused on the dynamic behavior of the tire at the contact area. Thus, a novel optical method based on light refraction and reflection is proposed for the measurement of contact area between the tread of the tire and a rigid transparent surface. To this end, constructing an indoor test rig is required. In this research, a three-dimensional drawing software has been used to analyze a customized testing facility. An indoor test rig has been designed and manufactured to visualize the contact area of a rolling tire. A digital camera has been used under a glass panel to record the tire footprint in detail during the test. The length, width, ratio, and shape of the tire footprint can be determined, which are related to the effect on tire traction performance. Based on the appropriate image processing techniques in the MATLAB, a precise reconstruction of tire footprint was realized. The results for the footprint properties of the tire with an applied normal load of 4 kN and tire inflation pressures of 21 Psi for free rolling, static state, and the different slip ratios are presented. Presented results in the paper will show that the system is robust enough to obtain a real-time dynamic measurement.