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We present an approach in which an open-source software infrastructure is used for testing the behavior of autonomous vehicles through computer simulation. This software infrastructure is called CAVE, from Connected Autonomous Vehicle Emulator. As a software platform that allows rapid, low-cost and risk-free testing of novel designs, methods and software components, CAVE accelerates and democratizes research and development activities in the field of autonomous navigation.

A hydrostatic dynamometer capable of accurately controlling the speed and torque of an engine has been designed and constructed. The thrust of this work is not only to build a better dynamometer, it is the first step in creating a system for laboratory simulation of the actual load environment of engines and powertrains. This paper presents the design, construction, and evaluation of a hydrostatic dynamometer. The evaluation includes speed and torque limits, and bandwidth of the dynamometer. Also, the dynamometer is compared with those in common use, and the feasibility of accurately reproducing the engine or powertrain load environments are assessed. This is the first phase of a development program; future research is discussed.

A direct calibration has been performed on laser-induced fluorescence measurements of the oil film in a single cylinder air-cooled research engine by simultaneously measuring the minimum oil film thickness by the capacitance technique. At the minimum oil film thickness the capacitance technique provides an accurate measure of the ring-wall distance, and this value is used as a reference for the photomultiplier voltage, giving a calibration coefficient. This calibration coefficient directly accounts for the effect of temperature on the fluorescent properties of the constituents of the oil which are photoactive. The inability to accurately know the temperature of the oil has limited the utility of off-engine calibration techniques. Data are presented for the engine under motoring conditions at speeds from 800 - 2400 rpm and under varying throttle positions.

Engine tests were conducted to study the effect of fuel-air mixture preparation on the combustion and emission performance of a two-stroke direct-injection engine. The in-cylinder mixture distribution was altered by changing the injection system, injection timing, and by substituting the air in an air-assisted injector with nitrogen. Two injection systems which produce significantly different mixtures were investigated; an air-assisted injector with a highly atomized spray, and a single-fluid high pressure-swirl injector with a dense penetrating spray. The engine was operated at overall A/F ratios of 30:1, where stratification was necessary to ensure stable combustion; and at 20:1 and 15:1 where it was possible to operate in a nearly homogeneous mode. Moderate engine speeds and loads were investigated. The effects of the burning-zone A/F ratio were isolated by using nitrogen as the working fluid in the air-assist injector.

Transient operation of automobile engines is known to contribute significantly to regulated exhaust emissions, and is also an area of drivability concerns. Furthermore, many on-board diagnostic algorithms do not perform well during transient operation and are often temporarily disabled to avoid problems. The inability to quickly and repeatedly test engines during transient conditions in a laboratory setting limits researchers and development engineers ability to produce more effective and robust algorithms to lower vehicle emissions. To meet this need, members of the Powertrain Control Research Laboratory (PCRL) at the University of Wisconsin-Madison have developed a high-bandwidth, hydrostatic dynamometer system that will enable researchers to explore transient characteristics of engines and powertrains in the laboratory.

This paper describes how a blend of silicon polymers, mixed with the right combination of fillers, enables the production of durable rubber IC engine head and exhaust gaskets. The resin blend, when mixed with glass fiber reinforcement, produces a liquid sealant suitable for exhaust gasket applications. The exhaust sealant and laminate head gaskets were tested on Ford 460 truck engines at Jasper Engine Company and completed more than 5,000 hours of durability testing without incident. Fabric reinforced polymer (FRP) head and exhaust gaskets can be laser cut from molded laminates, creating a ceramic glass-sealed edge. Thermogravimetric scans of typical gasket laminate material reveal an 88%-yield at 1000°C. FRP head gaskets also enable the cost-effective production of multiple spark ignition (MSI) head gaskets.

The focus of this paper is to discuss the modeling and control of intake plenum pressure on the Powertrain Control Research Laboratory's (PCRL) Single-Cylinder Engine (SCE) transient test system using a patented device known as the Intake Air Simulator (IAS), which dynamically controls the intake plenum pressure, and, subsequently, the instantaneous airflow into the cylinder. The IAS exists as just one of many devices that the PCRL uses to control the dynamic boundary conditions of its SCE transient test system to make it “think” and operate as though it were part of a Multi-Cylinder Engine (MCE) test system. The model described in this paper will be used to design a second generation of this device that utilizes both continuously and discretely actuating valves working in parallel.

The properties of aluminum alloys reinforced by ceramic nanoparticles (less than 100nm) would be enhanced considerably while the ductility is retained over that of the native alloy. The potential of bulk Al-based metal matrix nano-composites (Al MMNCs) cannot be fully developed for industrial applications unless complex structural Al MMNC components can be fabricated cost effectively, such as by casting. Reliable bulk Al MMNCs cannot be cast unless the nanoparticles can be dispersed and distributed uniformly in molten Al alloys. This paper investigates a high volume production method for high performance aluminum matrix nanocomposites, in particular, the application of high intensity ultrasonic cavitation in mixing and dispersing nano-sized ceramic particles in Al melts to cast bulk Al MMNCs for complex automobile structures. Nano-sized SiC particles have been dispersed in molten aluminum alloy A356 for casting.

This paper reviews the engine modeling program in the Powertrain Control Research Laboratory at the University of Wisconsin-Madison, focuses on simulation results obtained from a complete modular turbocharged diesel engine dynamic model developed in this lab, and suggests ways that dynamic engine system models can be used in the design process. It examines the dynamic responses and interactions between various components in the engine system, looks at how these components affect the overall performance of the system in transient and steady state operation.