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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.

This study examined an existing industrial workstation at an automobile assembly plant using computer aided ergonomics and digital human models. The purpose of this evaluation was the development of a methodology useful for evaluating workstations to identify potential design issues that could result in musculoskeletal injury in a real work environment. An ergonomic risk assessment was conducted on a lifting task while being performed both manually and using an assist device. JACK digital human modeling and ergonomics software were used to conduct a computer-based ergonomic analysis. Four analysis tools in JACK (static strength analysis, rapid upper limb assessment, metabolic energy expenditure analysis and NIOSH lift analysis) were used to evaluate the potential injury risk of the current method of task performance and there is any difference between using and not using the assist device. Muscle activity was measured by electromyography (EMG) to identify physiological indicators of fatigue. Also, Borg¡¯s Rate of Perceived Exertion (RPE) scale was administered to obtain psychophysical data. Results of this study revealed that there were relative stresses on the trunk and arm areas when the task was performed manually. The results also suggest although using the assist device decreased injury risk potentially, use of the assist device had an adverse impact on the productivity of the assembly line. Based on the findings of this study, the methodology used appears to be an appropriate ergonomic analysis tool for assessing and predicting potential risks associated with the design of industrial workstations. Furthermore this methodology can be extended to designing and redesigning industrial workstations.

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No description available.

No description available.

The automotive industry has become a major user of magnesium components. However, use of magnesium sheet products is quite limited, due to difficulties in producing cost effective components. Any sheet currently produced is formed at elevated temperatures, making magnesium parts relatively expensive. Knowledge of the microstructural effects on magnesium formability will help reduce the cost of these products. In this thesis, the microstructural factors that affect the formability of rolled and extruded magnesium sheet were compared. It was found that the degree of dynamic recrystallization was the factor that controlled elongation. Dynamic recrystallization produced a finer grain size, which resulted in a transition in deformation mechanism from dislocation slip to grain boundary sliding. Digital image correlation was used to study local stresses during tensile deformation, and to determine if magnesium satisfies Considere's criterion before failure. The results indicated that local stresses developed during deformation satisfied Considere's criterion, although the global strains were lower than the theoretical predictions. / Thesis / Master of Applied Science (MASc)

The purpose of this study was to determine if Automotive Service Excellence (ASE) certification of automotive service technicians in independent dealerships enhanced job performance. Descriptive survey methodology was used to gather information for 100 automotive technicians (50 ASE-certified and 50 non-certified technicians) located in 50 different work sites. Each site's service manager was asked to complete a questionnaire and a rating scale for two technicians, one ASE certified and one non-certified. The questionnaire was designed using expert opinions of automotive service managers and community college automotive instructors in the Triad area of North Carolina. The 28-item Minnesota Satisfactoriness Scales (MSS) were used to assess job satisfactoriness. Responses to 95 completed questionnaires and accompanying MSS were included in statistical analyses. The role of these variables in predicting ratings of job performance was further examined by including the regression analyses of only those who had four or less years of on-the-job experience. Among certified technicians, higher scale scores and longer years of experience positively predicted ratings of job performance, as well as decreased numbers of customer complaints. Overall, certified technicians had higher mean job performance ratings than non-certified technicians. Attendance and employee recognition did not significantly predict ratings of job performance in either category of technicians. Results indicated that the number of technicians receiving customer complaints was directly dependent on certification status. Variables such as awards and number of months of perfect attendance had minimal effect on both categories of technician job performance rating. / Ph. D.

This work describes the design, development and research applications of a Modular Automotive Technology Testbed (MATT). MATT is built to evaluate technology components in a hybrid vehicle system environment. MATT can also be utilized to evaluate energy management and torque split control strategies and to produce physical measured component losses and emissions to monitor emissions behavior. In the automotive world, new technology components are first developed on a test bench and then they are integrated into a prototype vehicle for transient evaluation from the vehicle system perspective. This process is expensive and the prototype vehicles are typically inflexible in hardware and software configuration. MATT provides flexibility in component testing through its component module approach. The flexible combination of modules provides a vehicle environment to test and evaluate new technology components. MATT also has an open control system where any energy management and torque split strategy can be implemented. Therefore, the control's impact on energy consumption and emissions can be measured. MATT can also emulate different types and sizes of vehicles. MATT is a novel, unique, flexible and powerful automotive research tool that provides hardware-based data for specific research topics. Currently, several powertrain modules are available for use on MATT: a gasoline engine module, a hydrogen engine module, a virtual scalable energy storage and virtual scalable motor module, a manual transmission module and an automatic transmission module. The virtual battery and motor module uses some component Hardware-In-the-Loop (HIL) principles by utilizing a physical motor powered from the electric grid in conjunction with a real time simulation of a battery and a motor model. This module enables MATT to emulate a wide variety of vehicles, ranging from a conventional vehicle to a full performance electric vehicle with a battery pack that has virtually unlimited capacity. A select set of PHEV research studies are described in this dissertation. One of these studies had an outcome that influenced the PHEV standard test protocol development by SAE. Another study investigated the impact of the control strategy on emissions of PHEVs. Emissions mitigation routines were integrated in the control strategies, reducing the measured emissions to SULEV limits on a full charge test. A special component evaluation study featured in this dissertation is the transient performance characterization of a supercharged hydrogen internal combustion engine on MATT. Four constant air-fuel ratio combustions are evaluated in a conventional vehicle operation on standard drive cycles. Then, a variable air fuel ratio combustion strategy is developed and the test results show a significant fuel economy gain compared to other combustion strategies, while NOx emissions levels are kept low. / Ph. D.

Remote attacks on vehicles have become alarmingly more common over the past decade. Attackers often can compromise a single Electronic Control Unit (ECU) in the In-Vehicle Network (IVN) and then use it to send malicious messages that can cause a vehicle to stop, turn, or even crash. It is critical that we find a way to block or discard these messages. However, current IVNs contain few measures to prevent such threats. Most research in this area focuses on cryptography-based approaches that are too slow or too expensive for vehicle applications. In this thesis, we explore how we can stop many of these remote attacks without cryptography. We define a `security policy' that describes what messages are allowed in an IVN and then create a system of distributed firewalls to enforce it, blocking many remote attacks. Using newer, switched IVN topologies, we can authenticate messages with nearly zero additional overhead and implement our system with minimal changes to each ECU. This places the security responsibility on a few centralized network devices that automakers can more easily control and update, even after a vehicle is sold. We evaluate our firewall design using a network simulator and find that our approach is significantly faster than state-of-the-art cryptographic approaches. / Master of Science / Over the past decade, hackers and security researchers have found many ways to remotely take control of a vehicle. Most modern vehicles contain numerous Electronic Control Units (ECUs) that each control some aspect of the vehicle, such as the brakes or engine. It is difficult to design all ECUs perfectly, however, and attackers are often able to remotely hack into one of them. From there, attackers can send malicious messages throughout the In-Vehicle Network (IVN) that connects ECUs. These messages can cause the car to stop, turn, or even crash. Thus, we must find a way to block or discard these messages. Most current research uses cryptography to accomplish this, which is a computationally expensive technique that uses math to determine if messages are legitimate. In this thesis, we examine how we can stop these malicious messages without cryptography. We introduce an approach based on firewalls, which are devices in the network that inspect messages and block them if they do not pass a set of rules. Our approach, which leverages new trends in IVN architectures, allows us to stop many of these malicious messages in the network with nearly zero additional overhead. In addition, our system of firewalls is much easier for an automaker to manage and update than previous approaches. We simulate our idea and find that it is significantly faster than previous state-of-the-art techniques.