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Contemporary manufacturing systems are still evolving. The system elements, layouts, and integration methods are changing continuously, and ‘collaborative robots’ (CoBots) are now being considered as practical industrial solutions. CoBots, unlike traditional CoBots, are safe and flexible enough to work with humans. Although CoBots have the potential to become standard in production systems, there is no strong foundation for systems design and development. The focus of this research is to provide a foundation and four tier framework to facilitate the design, development and integration of CoBots. The framework consists of the system level, work-cell level, machine level, and worker level. Sixty-five percent of traditional robots are installed in the automobile industry and it takes 200 hours to program (and reprogram) them.

Corona ignition is a promising technology that has been demonstrated to be capable of improving the reliability of lean combustion. However, arcing is unavoidable during corona discharge. The high current surge during arcing can cause excessive damage to the corona ignition system. In this work, a control framework is proposed to help reduce and prevent arcing from happening in a corona ignition system. Experimental results are demonstrated to show the effectiveness of the proposed methodology.

When performing trajectory planning for robotic applications, there are many aspects to consider, such as the reach conditions, joint and end-effector velocities, accelerations and jerk conditions, etc. The reach conditions are dependent on the end-effector orientations and the robot kinematic structure. The reach condition feasibility is the first consideration to be addressed prior to optimizing a solution. The ‘functional’ work space or work window represents a region of feasible reach conditions, and is a sub-set of the work envelope. It is not intuitive to define. Consequently, 2D solution approaches are proposed. The 3D travel paths are decomposed to a 2D representation via radial projections. Forward kinematic representations are employed to define a 2D boundary curve for each desired end effector orientation.

Laser cladding is a method of material deposition through which a powdered or wire feedstock material is melted and consolidated by use of a laser to coat part of a substrate. Determining the parameters to fabricate the desired clad bead geometry for various configurations is problematic as it involves a significant investment of raw materials and time resources, and is challenging to develop a predictive model. The goal of this research is to develop an experimental methodology that minimizes the amount of data to be collected, and to develop a predictive model that is accurate, adaptable, and expandable. To develop the predictive model of the clad bead geometry, an integrated five-step approach is presented. From the experimental data, an artificial neural network model is developed along with multiple regression equations.

Due to high torque and power density, permanent magnet synchronous motor (PMSM) has become the most viable candidate for electric vehicle (EV) traction application. However, to obtain such high torque and power density within a compact motor structure can cause a significant temperature rise within the motor while operating. As a result of high temperature rise, permanent magnet demagnetization may even occur within the motor. Thus, PMSM is susceptible to thermal instability. Therefore, to ensure thermal stability during varying operating conditions, thermal analysis is a mandatory procedure in addition to electromagnetic analysis during the design phase of the motor. In this paper, a computationally efficient numerical finite element analysis (FEA) process has been proposed for thermal analysis of PMSM.

To overcome the unfavorable operation conditions caused by lean/diluted charges in modern Spark Ignited (SI) engines, various advanced ignition systems have been proposed in the past. Among them, the dual-coil and multi-coil Transistor Coil Ignition (TCI) systems with offset discharge strategy caused significant attention in literature because they can generate a continuous spark with high spark energy being delivered into the cylinder. Comparing with the dual-coil system, a multi-coil system is capable to apply more flexible control strategies and generate a higher discharge current. However, the spark energy and transfer efficiency of the multi-coil system are still worthy to investigate as they are important performance indicators for a TCI system. In this paper, the discharge characteristics of the dual-coil and triple-coil strategies under both quiescent and flow conditions were studied firstly by experimental methods.

Thermal comfort in automotive seating has been studied and discussed for a long time. The available research, because it is focused on the components, has not produced a model that provides insight into the human-seat system interaction. This work, which represents the beginning of an extensive research program, aims to establish the foundation for such a model. This paper will discuss the key physiological, psychological, and biomechanical factors related to perceptions of thermal comfort in automotive seats. The methodology to establish perceived thermal comfort requirements will also be presented and discussed.

A semi-empirical turbulent flame growth model has been developed based on thermodynamic equilibrium calculations and experiments in a 125-mm cubical combustion chamber. It covers the main flame growth period from spark kernel formation until flame wall contact, including the effects of laminar flame speed, root mean square turbulence intensity, turbulent eddy size, and flame size. As expected, the combustion rate increases with increasing laminar flame speed and/or turbulence intensity. The effect of turbulent eddy scale is less obvious. For a given turbulence intensity, smaller scales produce higher instantaneous flame speed. However, turbulence of a smaller scale also decays more rapidly. Thus, for a given laminar flame speed and turbulence intensity at the time of ignition, there is an optimum turbulent eddy size which leads to the fastest combustion rate over the period considered.

The ever-growing demand to meet the stringent exhaust emission regulations have driven the development of modern gasoline engines towards lean combustion strategies and downsizing to achieve the reduction of exhaust emission and fuel consumption. Currently, the inductive ignition system is still the dominant ignition system applied in Spark Ignited (SI) engines. It is popular due to its simple design, low cost and robust performance. The new development in spark ignition engines demands higher spark energy to be delivered by the inductive ignition system to overcome the unfavorable ignition conditions caused by the increased and diluted in-cylinder charge. To meet this challenge, better understanding of the inductive ignition system is required. The development of a first principle model for simulation can help in understanding the working mechanism of the system in a better way.

In this study the capabilities of a semi-active suspension and an active roll suspension are evaluated for comparison with a passive suspension. The vehicle used is a utility truck modeled as a multi-body system in ADAMS/Car while the ECU (electronic control unit) is built in Matlab/Simulink. Cosimulation is used in linking the vehicle model with the controller by exchanging the input and output values of each sub-system with one another. For the simulation models considered, results indicate that for a fish-hook cornering maneuver the semi-active suspension is limited in increasing vehicle performance while the active roll suspension significantly improves it. Further analysis is needed to confirm these findings.

In this work, engine tests were performed to realize EGR-enabled LTC on a single-cylinder common-rail diesel engine with three different compression ratios (17.5, 15 and 13:1). The engine performance was first investigated at 17.5:1 compression ratio to provide baseline results, against which all further testing was referenced. The intake boost and injection pressure were progressively increased to ascertain the limiting load conditions for the compression ratio. To extend the engine load range, the compression ratio was then lowered and EGR sweep tests were again carried out. The strength and homogeneity of the cylinder charge were enhanced by using intake boost up to 3 bar absolute and injection pressure up to 180 MPa. The combustion phasing was locked in a narrow crank angle window (5~10° ATDC), during all the tests.

This work investigates the benefits and challenges of enabling neat n-butanol HCCI combustion on a high compression ratio (18.2:1) diesel engine. Minor engine modifications are made to implement n-butanol port injection while other engine components are kept intact. The impacts of the fuel change, from diesel to n-butanol, are examined through steady-state engine tests with independent control of the intake boost and exhaust gas recirculation. As demonstrated by the test results, the HCCI combustion of a thoroughly premixed n-butanol/air lean mixture offers near-zero smoke and ultralow NOx emissions even without the use of exhaust gas recirculation and produces comparable engine efficiencies to those of conventional diesel high temperature combustion. The test results also manifest the control challenges of running a neat alcohol fuel in the HCCI combustion mode.

In the recent decades, the emission and fuel efficiency regulations put forth by the emission regulation agencies have become increasingly stringent and this trend is expected to continue in future. The advanced spark ignition (SI) engines can operate under lean conditions to improve efficiency and reduce emissions. Under such lean conditions, the ignition and complete combustion of the charge mixture is a challenge because of the reduced charge reactivity. Enhancement of the in-cylinder charge motion and turbulence to increase the flame velocity, and consequently reduce the combustion duration is one possible way to improve lean combustion. The role of air motion in better air-fuel mixing and increasing the flame velocity, by enhancing turbulence has been researched extensively. However, during the ignition process, the charge motion can influence the initial spark discharge, resulting flame kernel formation, and flame propagation.

Clean diesel engines are one of the fuel efficient and low emission engines of interest in the automotive industry. The combustion chamber flow field and its effect on fuel spray characteristics plays an important role in improving the efficiency and reducing the pollutant emission in a direct injection diesel engine, in terms of influencing processes of breakup, evaporation mixture formation, ignition, combustion and pollutant formation. Ultra-high injection pressure fuel sprays have benefits in jet atomization, penetration and air entrainment, which promote better fuel-air mixture and combustion. CFD modeling is a valuable tool to acquire detailed information about these important processes. In this research, the characteristics of ultra-high injection pressure diesel fuel sprays are simulated and validated in a quiescent constant volume chamber. A profile function is utilized in order to apply variable velocity and mass flow rate at the nozzle exit.

Spark ignition systems with the capability of providing spark event with either higher current level or longer discharge duration has been developed in recent years to help IC engines towards clean combustion with higher efficiency under lean/diluted intake charge. In this research, a boosted current spark strategy was proposed to investigate the effect of spark discharge current level and discharge duration on the combustion process. Firstly, the discharge characteristics of a boosted current spark system were tested with a traditional spark plug under crossflow conditions, and results showed that the spark channel was more stable, and was stretched much longer when the discharge current was boosted. Then the boosted current strategy was used in a spark ignition engine operating under lean conditions. Boosted current was added to the spark channel with different timing, duration, and current levels.

Increasingly stringent emission standards have promoted the interest in alternate fuel sources. Because of the comparable energy density to the existing fossil fuels and renewable production, alcohol fuels may be a suitable replacement, or an additive to the gasoline/diesel fuels to meet the future emission standards with minimal modification to current engine geometry. In this research, the combustion characteristics of neat n-butanol are analyzed under spark ignition operation using a single cylinder SI engine. The fuel is injected into the intake manifold using a port-fuel injector. Two modes of charge dilution were used in this investigation to test the limits of stable engine operation, namely lean burn using excess fresh air and exhaust gas recirculation (EGR). The in-cylinder pressure measurement and subsequently, heat release analysis are used to investigate the combustion characteristics of the fuel under low load SI engine operation.

For spark ignition (SI) engines, further improvement of engine efficiency has become the major development trend, and lean burn/EGR technologies, as well as intensified in-cylinder flow, need to be adapted to reach that target. Stronger ignition sources become more favorable under extreme lean/EGR conditions. Among the ignition technologies developed, multiple ignition sites technology has been proved to be an effective way to help with the initial flame kernel development. In this paper, a spark ignited 4-cylinder turbo-charged production engine is employed to investigate the impact of multiple ignition sites technology on engine performance under lean burn conditions. Four in-house designed 3-core sparkplugs are installed on the cylinders to replace traditional stock sparkplugs, in order to generate multiple ignition sites in the cylinders.

End-of-life is the least studied phase of the vehicle life-cycle. Dismantling and shredding are the principal processes used for vehicle end-of-life (VEOL) management in Canada and the U.S. and are typically perceived as distinct processes, each one having its own unique challenges. Dismantling typically precedes shredding, with vehicle parts and materials removed for direct reuse, for remanufacturing and reuse, or for recycling. Dismantling may be perceived as a non-preferred alternative, compared to shredding, because it is principally a manual process which can be cost prohibitive in the North America/western labour market. However, there has been no exhaustive assessment of the dismantling process. Because of the complexity in automobiles, significantly more needs to be known about dismantling, its benefits and impacts, its efficiencies and inefficiencies, and its relation to other ELV management processes.

The purpose of this study is to determine the feasibility of simulating an active suspension using cosimulation. The vehicle used is a utility truck created in ADAMS/View while the E.C.U. (electronic control unit) is implemented in Simulink for both a fully-active and semi-active controller. The LQR (Linear Quadratic Regulator) is used for the fully-active system while the semi-active system uses a switching law adopted from Karnopp et al. {1}. Nonlinear and linear vehicle models are compared and the influence of suspension bushings is examined. All simulations undertaken are geared towards evaluating the ride capabilities of such systems.

A production V-8 engine was redesigned to run on low temperature combustion (LTC) with conventional Diesel fuel. Two fuel injection strategies were used to attain reduction in soot and NOx; a) early premixed injection strategy: fuel injected early during the compression stroke and b) late premixed injection strategy: fuel injected close to TDC with heavy EGR. The early premixed injection strategy yielded low NOx and soot but struggled to vaporize the fuel as noted in unburned hydrocarbons readings. The late premixed injection strategy introduced the fuel at higher in-cylinder temperatures and densities, improving the fuel's vaporization and limited the unburned hydrocarbon and carbon monoxide. The use of high EGR and high injection pressure for late premixed injection strategy provided sufficiently long ignition delay that resulted in partially premixed cylinder charge before combustion, and thereby prevented high soot, even in presence of high EGR.