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Environmental perception is considered an essential module for autonomous driving and Advanced Driver Assistance System (ADAS). Recently, deep Convolutional Neural Networks (CNNs) have become the State-of-the-Art with many different architectures in various object detection problems. However, performances of existing CNNs have been dropping when detecting small objects at a large distance. To deploy any environmental perception system in real world applications, it is important that the system achieves high accuracy regardless of the size of the object, distance, and weather conditions. In this paper, a robust sensor fused object detection system is proposed by utilizing the advantages of both vision and automotive radar sensors. The proposed system consists of three major components: 1) the Coordinate Conversion module, 2) Multi level-Sensor Fusion Detection (MSFD) system, and 3) Temporal Correlation filtering module.

Pending reductions in light duty vehicle PM emissions standards from 10 to 3 mg/mi and below will push the limits of the gravimetric measurement method. At these levels the PM mass collected approaches the mass of non-particle gaseous species that adsorb onto the filter from exhaust and ambient air. This introduces an intrinsic lower limit to filter based measurement that is independent of improvements achieved in weighing metrology. The statistical variability of back-up filter measurements at these levels makes them an ineffective means for correcting the adsorption artifact. The proposed subtraction of a facility based estimate of the artifact will partially alleviate the mass bias from adsorption, but its impact on weighing variability remains a problem that can reach a significant fraction of the upcoming 3 and future 1 mg/mi standards. This paper proposes an improved PM mass method that combines the gravimetric filter approach with real time aerosol measurement.

This paper includes a numerical and experimental study of fluid flow in automotive catalytic converters. The numerical work involves using computational fluid dynamics (CFD) to perform three-dimensional calculations of turbulent flow in an inlet pipe, inlet cone, catalyst substrate (porous medium), outlet cone, and outlet pipe. The experimental work includes using hot-wire anemometry to measure the velocity profile at the outlet of the catalyst substrate, and pressure drop measurements across the system. Very often, the designer may have to resort to offset inlet and outlet cones, or angled inlet pipes due to space limitations. Hence, it is very difficult to achieve a good flow distribution at the inlet cross section of the catalyst substrate. Therefore, it is important to study the effect of the geometry of the catalytic converter on flow uniformity in the substrate.

Kettering University's entry for the 2006 Clean Snowmobile challenge utilizes a Polaris FST Switchback. This snowmobile having a two cylinder, four-stroke engine has been modified to run on ethanol (E-85). The student team has designed and built a new exhaust system which features customized catalytic converters to minimize engine out emissions. A number of improvements have been made to the track to reduce friction and diminish noise.

Clean snowmobile technology has been developed using methods which can be applied in the real world with a minimal increase in cost. Specifically, a commercially available snowmobile using a two cylinder, four-stroke engine has been modified to run on high-blend ethanol (E-85) fuel. Additionally, a new exhaust system which features customized catalytic converters and mufflers to minimize engine noise and exhaust emissions has developed. Finally, a number of additional improvements have been made to the track to reduce friction and diminish noise. The results of these efforts include emissions reductions of 94% when compared with snowmobiles operating at the 2012 U.S. Federal requirements.

Mechanical counter-pressure (MCP) spacesuit designs have been a promising, but elusive alternative to historical and current gas pressurized spacesuit technology since the Apollo program. One of the important potential advantages of the approach is enhanced mobility as a result of reduced bulk and joint torques, but the literature provides essentially no quantitative joint torque data or quantitative analytical support. Decisions on the value of investment in MCP technology and on the direction of technology development are hampered by this lack of information since the perceived mobility advantages are an important factor. An experimental study of a simple mechanical counter-pressure suit (elbow) hinge joint has been performed to provide some test data and analytical background on this issue to support future evaluation of the technology potential and future development efforts.

Kettering University's entry in the 2003 Clean Snowmobile Challenge entails the installation of a fuel injected four-stroke engine into a conventional snowmobile chassis. Exhaust emissions are minimized through the use of a catalytic converter and an electronically controlled closed-loop fuel injection system, which also maximizes fuel economy. Noise emissions are minimized by the use of a specifically designed engine silencing system and several chassis treatments. Emissions tests run during the SAE collegiate design event revealed that a snowmobile designed by Kettering University produces lower unburned hydrocarbon (1.5 to 7 times less), carbon monoxide (1.5 to 7 times less), and oxides of nitrogen (and 5 to 23 times less) levels than the average automobile driven in Yellowstone National Park. The Kettering University entry also boasted acceleration performance better than the late-model 500 cc two-stroke snowmobile used as a control snowmobile in the Clean Snowmobile testing.

Numerical simulations of lean Methanol combustion in a four-stroke internal combustion engine were conducted on a high-compression ratio engine. The engine had a removable integral injector ignition source insert that allowed changing the head dome volume, and the location of the spark plug relative to the fuel injector. It had two intake valves and two exhaust ports. The intake ports were designed so the airflow into the engine exhibited no tumble or swirl motions in the cylinder. Three different engine configurations were considered: One configuration had a flat head and piston, and the other two had a hemispherical combustion chamber in the cylinder head and a hemispherical bowl in the piston, with different volumes. The relative equivalence ratio (Lambda), injection timing and ignition timing were varied to determine the operating range for each configuration. Lambda (λ) values from 1.5 to 2.75 were considered.

Impinging jets are an established technique for obtaining high local heat transfer coefficients between a fluid and a surface. Factors such as jet attachment, surface angle, jet angle, separation distance between jet orifice and surface of impingement, and trajectory influence heat transfer dramatically. In the current study, the specific application of interest is air issuing from the defroster's nozzles of a vehicle and impinging on a glass windshield. The current work is aimed at studying the flow patterns off a vehicle windshield as a result of air issuing from various nozzle configurations. The effects of openings' geometry (circular vs rectangular), number of openings, angle that the windshield makes with the horizontal plane and angle of impinging jet, on windshield heat transfer is examined. An optimal configuration will be recommended for better heat transfer.

Numerous human cadaver impact studies have shown that acute injury to the knee, femoral shaft, and hip may be significantly reduced by increasing the contact area over the anterior surface of the knee. Such impact events are common in frontal crashes when the knee strikes the instrument panel (IP). The cadaveric studies show that the injury threshold of the knee-thigh-hip complex increases as the contact area over the knee is likewise increased. Unfortunately, no prior methodology exists to record the spatial and temporal contact pressure distributions in dummy (or cadaver) experiments. Previous efforts have been limited to the use of pressure sensitive film, which only yields a cumulative record of contact. These studies assumed that the cumulative pressure sensitive film image correlated with the peak load, although this has never been validated.

A vehicle’s performance and fuel economy plays an important role in obtaining a larger market share in the segment. This can be best achieved by optimizing the aerodynamics of the vehicle. Aerodynamics can be improved by altering the bodylines on a vehicle. Its drag coefficient can be maintained at a minimum value by properly designing various component profiles. The stability of a vehicle and Passenger comfort are affected by wind noise that is related to the aerodynamics of a vehicle. To study the effects of the above-mentioned parameters, the vehicle is tested inside a wind tunnel. In this paper, the authors study the body profile for different vehicles and analyze them using Computational Fluid Dynamics software - FLUENT. To study the influence of different body profiles on drag coefficient, 3 different vehicle segments are considered.

A numerical study on the combustion of Methanol in a directly injected (DI) engine was conducted. The study considers the effect of the bowl-in-piston (BIP) geometry, swirl ratio (SR), and relative equivalence ratio (λ), on flame propagation and burn rate of Methanol in a 4-stroke engine. Ignition-assist in this engine was accomplished by a spark plug system. Numerical simulations of two different BIP geometries were considered. Combustion characteristics of Methanol under swirl and no-swirl conditions were investigated. In addition, the amount of injected fuel was varied in order to determine the effect of stoichiometry on combustion. Only the compression and expansion strokes were simulated. The results show that fuel-air mixing, combustion, and flame propagation was significantly enhanced when swirl was turned on. This resulted in a higher peak pressure in the cylinder, and more heat loss through the cylinder walls.

Kettering University's entry in the 2002 Clean Snowmobile Challenge involves the installation of a fuel injected four-stroke engine into a conventional snowmobile chassis. Exhaust emissions are minimized through the use of a catalytic converter and an electronically controlled closed-loop fuel injection system, which also maximizes fuel economy. Noise emissions are minimized by the use of a specifically designed engine silencing system and several chassis treatments. Emissions tests run during the SAE collegiate design event revealed that a snowmobile designed by Kettering University produces lower unburned hydrocarbon (1.5 to 7 times less), carbon monoxide (1.5 to 7 times less), and oxides of nitrogen (and 5 to 23 times less) levels than the average automobile driven in Yellowstone National Park. The Kettering University entry also boasted acceleration performance better than the late-model 500 cc two-stroke snowmobile used as a control snowmobile in the Clean Snowmobile testing.

A dimensionless relationship that estimates the maximum bearing load of a 4-cylinder 4-stroke in-line engine has been found. This relationship may assist the design engineer in choosing a desired counterweight mass. It has been demonstrated that: 1) the average bearing load increases with engine speed and 2) the maximum bearing load initially decreases with engine speed, reaches a minimum, then increases quickly with engine speed. This minimum refers to a transition speed at which the contribution of the inertia force overcomes the contribution of the maximum pressure force to the maximum bearing load. The transition speed increases with an increase of counterweight mass and is a function of maximum cylinder pressure and the operating parameters of the engine.

Tires are one of the major sources of noise and vibration in vehicles. The vibration characteristic of a tire depends on its resonant frequencies and mode shapes. Hence, it is desirable to study how different parameters affect the characteristics of tires. In the current paper, experimental modal tests are performed on a tire in free-free and fixed conditions. To obtain the mode shapes and the natural frequencies, the tire is excited using a mechanical shaker and the response of the tire to the excitation is measured using three roving tri-axial accelerometers. The mode shapes and resonant frequencies of the tire are extracted using LMS PolyMax modal analysis. The obtained mode shapes in the two configurations are compared using Modal Assurance Criterion (MAC) to show how mode shapes of tires change when the tire is moved from a free-free configuration to a fixed configuration. It is shown that some modes of the tire are more sensitive to boundary conditions.

A numerical and experimental study of the use of air motion control, piston bowl shape, and injector configuration on combustion and emissions in diesel engines has been conducted. The objective of this study is to investigate the use of flow control within the piston bowl during compression to enhance fuel air mixing to achieve a uniform air-fuel mixture to reduce soot and NO emissions. In addition to flow control different piston bowl geometries and injector spray angles have been considered and simulated using three-dimensional computational fluid dynamics and experiments. The results include cylinder pressure and emissions measurements and contour plots of fuel mass fraction, soot, and NO. The results show that soot and NO emissions can be reduced by proper flow control and piston bowl design.

A coupler has been developed to prevent windshield wiper systems from being damaged by excessive loads that can occur when the normal wiping pattern is restricted. The coupler is composed of a pultruded composite rod with injection-molded plastic spherical joints (a.k.a. sockets) attached at either end. The sockets are used to attach the coupler to the crank and rocker of the windshield wiper linkage. Because the loads exerted on a coupler vary in magnitude and direction during a wiping cycle, the joint between the sockets and the pultruded composite rod must be robust. The paradigm for attaching sockets to steel couplers (i.e. over-molding the sockets around holes stamped into the ends of traditional steel couplers) was applied to the pultruded rods, tested, and found to produce inadequate joint strength. This paper details the methodology that was employed to produce and optimize an acceptable means to attach the injection-molded sockets to the pultruded rods.

Large hood mounted plastic trim components are subjected to complex and often extreme loading conditions. Typical loading conditions include solar and thermal cycling, as well as road and powertrain induced vibrations, aero lift and buffeting, and mechanical loads such as car wash. For the above components understanding and classifying the typical loading conditions is an essential and important step in achieving long term quality. This paper discusses different approaches to the design, analysis, development, and testing of plastic trim components. Samples of analysis and test results are presented to demonstrate how to identify and prevent the loss of the part function. Some useful guidelines and practices for addressing thermal expansion, dimensional variation, and redundancy in attachments are also discussed.

Doors inside an automotive HVAC module are essential components to ensure occupant comfort by controlling the cabin temperature and directing the air flow. For temperature control, the function of a door is not only to close/block the airflow path via the door seal that presses against HVAC wall, but also control the amount of hot and cold airflow to maintain cabin temperature. To meet the stringent OEM sealing requirement while maintaining a cost-effective product, a “V-Shape” soft rubber seal is commonly used. However, in certain conditions when the door is in the position other than closed which creates a small gap, this “V-Shape” seal is susceptible to the generation of objectionable whistle noise for the vehicle passengers. This nuisance can easily reduce end-customer satisfaction to the overall HVAC performance.

Much development in the automotive industry relates to the use of high-content ethanol blended fuels to reduce the emissions produced by on-road engines/vehicles. However, less research has been done on the effect of operating small off-road engines (SORE) on high-blend ethanol fuels without substantial modifications. Most manufacturers of such engines only certify proper operation on low content ethanol blends such as E10 (10% ethanol, 90% gasoline by volume). This paper focuses on the use of E77 fuel in a small off-road engine which is speed-governed. Such engines are commonly used in lawn mowers, small recreational vehicles, or other equipment. The exhaust emissions and performance of the engine were evaluated using the EPA 6-mode duty cycle for small recreational engines where testing and analysis followed the recommendations of SAE J1088. This test cycle consisted of operating the engine at steady state load points using a fixed engine speed.