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Industrial robotic arms and manipulators are systems that offer technological advances in automation, production, and logistical processes. Therefore, it is vital to understand and analyze the reachability and dexterity of such manipulators. This paper presents a reconfigurable algorithm for evaluation and 3D visual representation of the total workspace and singularity space of two and three degrees of freedom open-ended kinematic chains. A manipulator's performance is greatly depreciated at or near singular regions which may occur as subset(s) in its complete workspace. It is therefore crucial to understand the functional workspace of a manipulator for an enhanced performance in an industrial setting. The implementation of this algorithm requires two inputs namely; the joint type(s), rotational (R) or translational (T), and the Denavit-Hartenberg (D-H) parameters of the manipulator.

Diesel fueling and exhaust flow strategies are investigated to control the substrate temperatures of diesel aftertreatment systems. The fueling control includes the common-rail post injection and the external supplemental fuel injection. The post injection pulses are further specified at the early, mid, or late stages of the engine expansion stroke. In comparison, the external fueling rates are moderated under various engine loads to evaluate the thermal impact. Additionally, the active-flow control schemes are implemented to improve the overall energy efficiency of the system. In parallel with the empirical work, the dynamic temperature characteristics of the exhaust system are simulated one-dimensionally with in-house and external codes. The dynamic thermal control, measurement, and modeling of this research intend to improve the performance of diesel particulate filters and diesel NOx absorbers.

A vehicle undergoing longitudinal or lateral accelerations experiences load transfer, dynamically changing the normal load carried by each tire. Conventional braking systems are designed only to work adequately over a large range of conditions, but often ignore the dynamic state of the tire's normal load. Fortunately, new developments in braking system hardware give designers more control over the application of braking pressures. By identifying the tires that carry increased normal load, and biasing the braking system toward those tires, total braking force can be increased. The purpose of this research is to investigate advantages of open-loop load transfer based active brake pressure distribution. By estimating the tractive ability of the tires as a function of measurable vehicle conditions, brake pressure can be applied in proportions appropriate for the current dynamic state of the vehicle, referred to as Active Brake Proportioning (ABP).

Exhaust gas recirculation (EGR) is effective to reduce nitrogen oxides (NOx) from diesel engines. However, when excessive EGR is applied, the engine operation reaches zones with higher combustion instability, carbonaceous emissions, and power losses. In order to improve the engine combustion process with the use of heavy EGR, the influences of boost pressure, intake temperature, and fuel injection timing are evaluated. An adaptive fuel injection strategy is applied as the EGR level is progressively elevated towards the limiting conditions. Additionally, characterization tests are performed to improve the control of the homogeneous charge compression ignition (HCCI) type of engine cycles, especially when heavy EGR levels are applied to increase the load level of HCCI operations. This paper constitutes the preparation work for a variety of algorithms currently being investigated at the authors' laboratory as a part of the model-based NOx control research.

Low temperature combustion (LTC), though effective to reduce soot and oxides of nitrogen (NOx) simultaneously from diesel engines, operates in narrowly close to unstable regions. Adaptive control strategies are developed to expand the stable operations and to improve the fuel efficiency that was commonly compromised by LTC. Engine cycle simulations were performed to better design the combustion control models. The research platform consists of an advanced common-rail diesel engine modified for the intensified single cylinder research and a set of embedded real-time (RT) controllers, field programmable gate array (FPGA) devices, and a synchronized personal computer (PC) control and measurement system.

Extensive empirical work indicates that the exhaust emission and fuel efficiency of modern common-rail diesel engines characterise strong resilience to biodiesel fuels when the engines are operating in conventional high temperature combustion cycles. However, as the engine cycles approach the low temperature combustion (LTC) mode, which could be implemented by the heavy use of exhaust gas recirculation (EGR) or the homogeneous charge compression ignition (HCCI) type of combustion, the engine performance start to differ between the use of conventional and biodiesel fuels. Therefore, a set of fuel injection strategies were compared empirically under independently controlled EGR, intake boost, and exhaust backpressure in order to improve the neat biodiesel engine cycles.

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.

The heterogeneous nature of direct injection (DI) combustion yields high combustion efficiencies but harmful emissions through the formation of high nitrogen oxide (NOx) and smoke emissions. In response, extensive empirical and computational research has focused on balancing the NOx-smoke trade-off to limit diesel DI combustion emissions. Dimethyl ether (DME) fuel is applicable in DI compression ignition engines and its high fuel oxygen produces near-smoke-free emissions. Moreover, the addition of a premixed fuel can improve mixture homogeneity and minimize the DI fuel energy demands lessening injection durations. For this technique, a low reactivity fuel such as ethanol is essential to avoid early autoignition in high compression ratio engines. In this work, empirical experiments of dual fuel operation have been conducted using premixed ethanol with high-pressure direct injection DME.

Electric power steering (EPS) systems have been used to replace hydraulic power steering systems in vehicles. How to enhance the safety and reliability while reducing the manufacturing cost of EPS systems is still of strong interest to the automotive industry. In this paper, modeling analysis is conducted for advanced control of electric power steering system. Specifically, a mathematical model is proposed for a column-mounted EPS system and then a simplified model for control design purpose is proposed. Issues that need to be addressed, such as noise/ disturbance attenuation as well as potential fault detection/tolerance are analyzed. Simulation using CarSim™ is also presented for an optimal control design using the simplified model as an example to validate the proposed ideas.

Amid all nondestructive testing (NDT) methods Ultrasound is considered the most practically feasible modality for quality assessment and detection of defects in automobile industry. Pattern recognition of the ultrasonic signals gives us important information about the interrogated object. This information includes size, geometric shape and location of the defect zone. However, this would not be straightforward to extract this information from the backscattered echoes due to the overlapping signals and also the presence of noise. Here in this study, we suggest a new method for classification of different defects in inspection of adhesively bonded joint. At the first step of this method, the problem of parameter estimation of the reflected echoes is defined in a Maximum Likelihood Estimation (MLE) framework. Then a space alternating generalized Expectation Maximization (SAGE) algorithm is implemented to solve the MLE problem.

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.

The paper describes a study conducted by the University of Windsor Vehicle Dynamics and Control Research Group into the stability of coupled vehicles, e.g., truck-trailer combinations. Several instabilities associated with truck-trailer combinations have been well documented, and have been predicted using mathematical models. Despite having relatively low complexity the classic truck-trailer model, a simple two body, three degree of freedom, linear model has been used extensively in coupled vehicle stability analyses. The aim of the presented work was to extend the conventional coupled vehicle analysis with a set of more elaborate mathematical models evaluating various vehicle configurations. Using in-house multibody dynamics software the linearized equations of motion of three dimensional models were automatically generated for various coupled vehicle configurations with general and military applications. Stability analyses were conducted over a range of expected operating speeds.

Aluminum engines have been successfully used to replace heavy gray cast engines to lighten the car's weight and reduce the fuel consumption. To overcome the aluminum alloys' poor wear resistance, cast iron liners and thermal spraying coatings were used as cylinder bore materials for wear protection. A plasma electrolytic oxidation (PEO) technique had also been proposed to produce an oxide coating on aluminum cylinder bore. The oxide coating can have a low coefficient of friction (COF) and minimum wear shown in the lab tests. To conserve more fuel, the stopping and restarting system was introduced when the vehicle was forced to stop immediately for a short time. When the engine was forced to stop and restart, the reciprocating speed of the piston was very slow, and the friction between the piston and the cylinder was high. In this research, a pin-on-disc tribometer was used to investigate tribological behavior of the oxide coating on an aluminum alloy.

Exhaust gas recirculation, fuel injection strategy and boost pressure are among the key enablers to attain low NOx and soot emissions simultaneously on modern diesel engines. In this work, the individual influence of these parameters on the emissions are investigated independently for engine loads up to 8 bar IMEP. A single-shot fuel injection strategy has been deployed to push the diesel cycle into low temperature combustion with EGR. The results indicated that NOx was a stronger respondent to injection pressure levels than to boost when the EGR ratio is relatively low. However, when the EGR level was sufficiently high, the NOx was virtually grounded and the effect of boost or injection pressure becomes irrelevant. Further tests indicated that a higher injection pressure lowered soot emissions across the EGR sweeps while the effect of boost on the soot reduction appeared significant only at higher soot levels.

Preliminary empirical and modeling analyses are conducted to evaluate the energy efficiency of in-cylinder and external fuel injection strategies and their impact on the energy required to enable diesel particulate filter (DPF) regeneration for instance. During the tests, a thermal wave that is generated from the engine propagates along the exhaust pipe to the DPF substrate. The thermal response of the exhaust system is recorded with the thermocouple arrays embedded in the exhaust system. To implement the external fuel injection, an array of thermocouples and pressure sensors in the DPF provide the necessary feedback to the control system. The external fuel injection is dynamically adjusted based on the thermal response of the DPF substrate to improve the thermal management and to reduce the supplemental energy. This research intends to quantify the effectiveness of the supplemental energy utilization on aftertreatment enabling.

As European and Chinese tailpipe emission regulations for gasoline light-duty vehicles impose particulate number limits, automotive manufacturers have begun equipping some vehicles with a gasoline particulate filter (GPF). Increased understanding of how soot morphology, reactivity, and GPF loading affect GPF filtration and regeneration characteristics is necessary for advancing GPF performance. This study investigates the impacts of morphology, reactivity, and filter soot loading on GPF filtration and regeneration. Soot morphology and reactivity are varied through changes in fuel injection parameters, known to affect soot formation conditions. Changes in morphology and reactivity are confirmed through analysis using a transmission electron microscope (TEM) and a thermogravimetric analyzer (TGA) respectively.

Ferritic nitrocarburizing offers excellent wear, scuffing, corrosion and fatigue resistance by producing a thin compound layer and diffusion zone containing ε (Fe2-3(C, N)), γ′ (Fe4N), cementite (Fe3C) and various alloy carbides and nitrides on the material surface. It is a widely accepted surface treatment process that results in smaller distortion than carburizing and carbonitriding processes. However this smaller distortion has to be further reduced to prevent the performance issues, out of tolerance distortion and post grinding work hours/cost in an automotive component. A numerical model has been developed to calculate the nitrogen and carbon composition profiles of SAE 1010 torque converter pistons during nitrocarburizing treatment. The nitrogen composition profiles are modeled against the part thickness to predict distortion.

Simultaneous low NOx (< 0.15 g/kWh) & soot (< 0.01 g/kWh) are attainable for enhanced premixed combustion that may lead to higher levels of hydrocarbons and carbon monoxide emissions as the engine cycles move to low temperature combustion, which is a departure from the ultra low hydrocarbon and carbon monoxide emissions, typical of the high compression ratio diesel engines. As a result, the fuel efficiency of such modes of combustion is also compromised (up to 5%). In this paper, advanced strategies for fuel injection are devised on a modern 4-cylinder common rail diesel engine modified for single cylinder research. Thermal efficiency comparisons are made between the low temperature combustion and the conventional diesel cycles. The fuel injection strategies include single injection with heavy EGR, and early multi-pulse fuel injection under low or medium engine loads respectively.

Empirical results indicated that the engine emission and fuel efficiency of low-temperature combustion (LTC) cycles can be optimized by adjusting the fuel-injection scheduling in order to obtain appropriate combustion energy release or heat-release rate patterns. Based on these empirical results the heat-release characteristics were correlated with the regulated emissions such as soot, hydrocarbon and oxides of nitrogen. The transition from conventional combustion to LTC with the desired set of heat-release rate has been implemented. This transition was facilitated with the simplified heat-release characterization wherein each of the consecutive engine cycles was analyzed with a real-time controller embedded with an FPGA (field programmable gate array) device. The analyzed results served as the primary feedback control signals to adjust fuel injection scheduling. The experimental efforts included the boost/backpressure, exhaust gas recirculation, and load transients in the LTC region.

Whole field displacement/strain measurement of automotive components can be done efficiently by digital image correlation based technique. Inverse problems with this kind of input data, such as the identification of damage parameters/effective modulus in different part of a component, can be pursued by either virtual fields method or finite element model updating. In this paper, the two methods are applied to the identification of a tension plate with a circular hole, and different aspects of the two methods are discussed. It is found that the success of virtual fields method relies on the choice of a set of optimal virtual displacement fields; finite element model updating, on the other hand, can be applied to any geometry and any load condition, and can also be applied to problems where only limited number of measurements are available. However, its performance relies on the choice of optimization algorithms.