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The handling of flexible components creates a unique problem set for pick and place automation within automotive production processes. Fabrics and woven textiles are examples of flexible components used in car interiors, for air bags, as liners and in carbon-fiber layups. These textiles differ greatly in geometry, featuring complex shapes and internal slits with varying material properties such as drape characteristics, crimp resistance, friction, and fiber weave. Being inherently flexible and deformable makes these materials difficult to handle with traditional rigid grippers. Current solutions employ adhesive, needle-based, and suction strategies, yet these systems prove a higher risk of leaving residue on the material, damaging the weave, or requiring complex assemblies. Pincer-style grippers are suitable for rigid components and offer strong gripping forces, yet inadvertently may damage the fabric, and introduce wrinkles / folded-over edges during the release process.

In recent years, bearing electrical failures have been a significant concern in electric cars, restricting electric engine life. This work aims to introduce a coating approach for preventing electrical erosion on 52100 alloy steel samples, the most common material used on manufacturing bearings. This paper discusses the causes of shaft voltage and bearing currents, and summarizes standard electrical bearing failure mechanisms, such as morphological damages and lubrication failures. Alumina coatings are suitable for insulating the 52100 alloy steel samples because alumina coatings provide excellent insulation, hardness, and corrosion resistance, among other characteristics. The common method to coat an insulated alumina coating on the bearing is thermal spraying, but overspray can cause environmental issues, and the coating procedures are costly and time-consuming.

Due to the reduced or less-frequent usages of the friction brakes and the lower brake rotor temperature on electrical vehicles (EV), corrosion would much likely occur on brake rotors. Using hard braking to clean the corroded rotor surfaces often leads to extra rotor surface wear. Improvement in corrosion and wear resistance is an important technological topic to brake rotors for EVs. Many original equipment manufacturers (OEM) and their suppliers are exploring surface treatments including laser cladding and thermal spray processes on cast iron rotors to combat the corrosion issues. However, mentioned surface coating processes increase the cost of brake rotors and there is a need to search for cost-effective coating processes. In this research, a new Al2O3-Ni composite coating was proposed for preparation of a commercial cast iron brake rotor using plasma electrolytic aluminating (PEA) followed by electroless nickel plating (ENP) processes.

Performance of the ignition system becomes more important than ever, because of the extensively used EGR in modern spark-ignition engines. Future lean burn SI and SACI combustion modes demand even stronger ignition capability for robust ignition control. For spark-based ignition systems, extensive research has been carried out to investigate the discharge characteristics of the ignition process, including discharge current amplitude, discharge duration, spark energy, and plasma stretching. The correlation between the spark stretch and the discharge energy, as well as the impact of discharge current level on this correlation, are important with respect to both ignition performance, and ignition system design. In this paper, a constant volume combustion chamber is applied to study the impact of plasma stretch on the spark energy release process with cross-flow speed from 0 m/s up to 70 m/s.

The axial cutting deformation mode is a novel alternative to progressive folding, the current state-of-the-art, where the cutting scheme exhibits more favorable mechanical performance. By splitting the extrusion into multiple evenly spaced and near-identical petals a highly consistent force response can be achieved. Maximizing the energy absorbing capacity of a sacrificial energy absorber is a fundamental design challenge in the field of crashworthiness. Generating hybrid deformation modes by simultaneously combining multiple deformation mechanisms into a single safety system is a promising technique to achieve high capacity energy dissipation. However, these systems tend to be susceptible to transitioning deformation modes (e.g. from progressive folding to global bending) since the sacrificial material is often loaded at or near its capacity.

Gray cast iron brake rotor experiences substantial wear during braking and contributes largely to the wear debris emissions. Surface coating on the gray cast iron rotor represents a trending approach dealing with the problems. In this research, a new plasma electrolytic aluminating (PEA) process was used for preparing an alumina-based ceramic coating with metallurgical bonding to the gray cast iron. Three different types of brake pads (ceramic, semi-metallic and non asbestos organic (NAO)) were used for tribotests. Performances of PEA coatings vs. different brake pad materials were comparatively investigated with respect to their coefficients of friction (COFs) and wear. The PEA-coated brake rotor has a dimple-like surface which promotes the formation of a thin transferred film to protect the rotor from wear. The transferred film materials come from the wear debris of the pads. The secondary plateaus are regenerated on the brake pads through compacting wear debris of the pads.

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.

Advanced ignition systems with enhanced discharge current have been extensively investigated in research, since they are highly regarded as having the potential to overcome challenges that arise when spark-ignition engines are running under lean or EGR diluted conditions. Local flow field is also of particular importance to improve the ignitability of the air-fuel mixture in SI engines as the spark plasma channel can be stretched by the flow across the spark gap, leading to longer plasma length, thus more thermal spark energy distributed to the air-fuel mixture in the vicinity of the spark plug. Research results have shown that a constantly high discharge current is effective to maintain a stable spark plasma channel with less restrikes and longer plasma holding period.

A plethora of applications in the transportation industry for both vehicular and roadside safety hardware, especially seatbelts, harnesses and restraints, rely on tensile loading to dissipate energy and minimize injury. There are disadvantages to the current state-of-the-art for these tensile energy absorbers, including erratic force-displacement responses and low tensile force efficiencies (TFE). Axial cutting was extensively demonstrated by researchers at the University of Windsor to maintain a stable reaction force, although exclusively under compressive loading. A novel apparatus was investigated in this study which utilized axial cutting under a tensile loading condition to absorb energy. A parametric scope was chosen to include circular AA6061 extrusions in both T4 and T6 temper conditions with an outer diameter of 63.5 mm and wall thickness of 3.18 mm.

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.

The breakdown phase is considered to have the highest electric-thermal energy transfer efficiency among all the discharge modes in a conventional spark ignition process. In this study, an external capacitor is connected in parallel with the spark plug in order to enhance the discharge energy and power during the breakdown phase. A constant volume combustion chamber is used to investigate the high power spark discharge under different background pressures and with varied flow velocities. Results show that the added parallel capacitance is effective in redistributing the spark energy. With the increase in parallel capacitance, the breakdown power and energy increase, though at the cost of reduced glow phase energy. The breakdown energy also increases with the increased background pressure. Then combustion tests are carried out to study the effects of the breakdown power enhanced spark on flame propagation under both quiescent and flow conditions via optical diagnosis.

Conventional axially loaded energy absorbers dissipate kinetic energy through progressive folding. The significant fluctuations in load and high risk of transition to global bending are drawbacks that engineers have attempted to mitigate through several methods. A novel energy dissipation mechanism, referred to as axial cutting, utilizes thin-walled extrusions and a strengthened cutting tool to absorb energy in an axial impact. Compared to progressive folding, this can be achieved with minimal fluctuations in load during the deformation process. Based upon estimates from finite element models, a series of test cases were postulated where, for 8 and 10-bladed cutting scenarios, greater total energy absorption could be achieved through axial cutting than with progressive folding of geometrically similar extrusions. The specimens were AA6061 extrusions having T6 temper conditions that possessed 63.5 mm outer diameters and 1.5 mm wall thicknesses.

A Split-Cycle engine fueled with methane has been constructed and operated at the University of Windsor. A split-cycle engine consists of two interconnected cylinders working together to preform the four engine strokes. Cylinder 1 preforms intake and compression strokes while cylinder 2 is where combustion, expansion and exhaust occur. The connecting high pressure crossover passage is where methane is injected, resulting in a well pre-mixed air-fuel mixture. Transfer occurs to the combustion cylinder near TDC, resulting in intense small scale turbulence that leads to short combustion durations under 30° CA. Short durations are achieved despite low engine speeds of 850-1200 rpm, late combustion phasing and part loads. Of note is the lean limit of operation of the engine at the equivalence ratio Φ = 0.85, which is high compared to other natural gas engines which have limits around Φ = 0.6.

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.

Carbon fiber sheet molding compound (SMC) is an attractive material for automotive lightweighting applications, but several issues present themselves when adapting a process developed for glass fiber composites to instead use carbon fibers. SMC is a discontinuous fiber material, so individual carbon fiber tows must be chopped into uniform rovings before being compounded with the resin matrix. Rotary chopping is one such method for producing rovings, but high wear rates are seen when cutting carbon fibers. Experiments were performed to investigate the wear progression of cutting blades during rotary carbon fiber chopping. A small rotary chopper with a polyurethane (PU) backing and thin, hardened steel blades was used to perform extended wear tests (120,000 chops, or until failure to reliably chop tows) to simulate the lifespan of blades during composite material production.

Close-loop feedback combustion control is essential for improving the internal combustion engines to meet the rigorous fuel efficiency demands and emission legislations. A vital part is the combustion sensing technology that diagnoses in-cylinder combustion information promptly, such as using cylinder pressure sensor and ion current measurement. The promptness and fidelity of the diagnostic are particularly important to the potential success of using intra-cycle control for abnormal cycles such as super knocking and misfiring. Many research studies have demonstrated the use of ion-current sensing as feedback signal to control the spark ignition gasoline engines, with the spark gap shared for both ignition and ion-current detection. During the spark glow phase, the sparking current may affect the combustion ion current signal. Moreover, the electrode gap size is optimized for sparking rather than measurement of ion current.

Laser cladding is used to coat a surface of a metal to enhance the metallurgical properties at the surface level of a substrate. For surface cladding operations, overlapping bead geometry is required. Single bead analyses do not provide a complete representation of essential properties; hence, this research focuses on overlapping conditions. The research scope targets the coaxial laser cladding process specifically for P420 stainless steel clad powder using a fiber optic laser with a 4.3 mm spot size on a low/medium carbon structural steel plate (AISI 1018). Many process parameters influence the bead geometrical shape, and it is assumed that the complex temperature distributions within the process could cause subsequent large variations in hardness values. The bead overlap configurations experiments are performed with 40%, 50% and 60% bead overlaps for a three-pass bead formation.

Laser cladding is a novel process of surface coating, and researchers in both academia and industry are developing additive manufacturing solutions for large, metallic components. There are many interlinked process parameters associated with laser cladding, which may have an impact on the resultant microhardness profile throughout the bead zone. A set of single bead laser cladding experiments were done using a 4 kW fiber laser coupled with a 6-axis robotic arm for 420 martensitic stainless steel powder. A design of experiments approach was taken to explore a wide range of process parameter settings. The goal of this research is to determine whether robust predictive models for hardness can be developed, and if there are predictive trends that can be employed to optimize the process settings for a given set of process parameters and microhardness requirements.

Cylindrical extrusions of magnesium AZ31B were subjected to quasi-static axial compression and cutting modes of deformation to study this alloy’s effectiveness as an energy absorber. For comparison, the tests were repeated using extrusions of AA6061-T6 aluminum of the same geometry. For the axial compression tests, three different end geometries were considered, namely (1) a flat cutoff, (2) a 45 degree chamfer, and (3) a square circumferential notch. AZ31B extrusions with the 45 degree chamfer produced the most repeatable and stable deformation of a progressive fracturing nature, referred to as sharding, with an average SEA of 40 kJ/kg and an average CFE of 45 %, which are nearly equal to the performance of the AA6061-T6. Both the AZ31B specimens with the flat cutoff and the circumferential notch conditions were more prone to tilt mid-test, and lead to an unstable helical fracture, which significantly reduced the SEA.

Friction between the piston and cylinder accounts for large amount of the friction losses in an internal combustion (IC) engine. Therefore, any effort to minimize such a friction will also result in higher efficiency, lower fuel consumption and reduced emissions. Plasma electrolytic oxidation (PEO) coating is considered as a hard ceramic coating which can provide a dimpled surface for oil retention to bear the wear and reduce the friction from sliding piston rings. In this work, a high speed pin-on-disc tribometer was used to generate the boundary, mixed and hydrodynamic lubrication regimes. Five different lubricating oils and two different loads were applied to do the tribotests and the COFs of a PEO coating were studied. The results show that the PEO coating indeed had a lower COF in a lower viscosity lubricating oil, and a smaller load was beneficial to form the mixed and hydrodynamic lubricating regimes earlier.