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The requirements of suspension systems have become increasingly complex in recent years due to the expansion of global markets and diversification of the conditions under which vehicles are used in different parts of the world. It is also becoming increasingly important to ensure that vehicles offer the secure handling stability which are expected by drivers, but can also provide an adequate level of ride comfort when driving on a wide diversity of road surfaces in all parts of the world. From an environmental viewpoint, it is also essential to achieve weight reductions for better fuel economy. To meet these wide-ranging requirements, we have developed a new multi-link rear suspension that has a simple link configuration and a lower link that features a connecting bushing mechanism developed by Nissan.

There is significant potential for connected and autonomous vehicles to impact vehicle efficiency, fuel economy, and emissions, especially for hybrid-electric vehicles. These improvements could have large-scale impact on oil consumption and air-quality if deployed in large Mobility-as-a-Service or ride-sharing fleets. As part of the US Department of Energy's current Advanced Vehicle Technology Competition (AVCT), EcoCAR: The Mobility Challenge, Mississippi State University’s EcoCAR Team is redesigning and doing the development work necessary to convert a conventional gasoline spark-ignited 2019 Chevy Blazer into a hybrid-electric vehicle with SAE Level 2 autonomy. The target consumer segments for this effort are the Mobility-as-a-Service fleet owners, operators and riders. To accomplish this conversion, the MSU team is implementing a P4 mild hybridization strategy that is expected to result in a 30% increase in fuel economy over the stock Blazer.

Although turbocharging can extend the high load limit of low temperature combustion (LTC) strategies such as reactivity controlled compression ignition (RCCI), the low exhaust enthalpy prevalent in these strategies necessitates the use of high exhaust pressures for improving turbocharger efficiency, causing high pumping losses and poor fuel economy. To mitigate these pumping losses, the divided exhaust period (DEP) concept is proposed. In this concept, the exhaust gas is directed to two separate manifolds: the blowdown manifold which is connected to the turbocharger and the scavenging manifold that bypasses the turbocharger. By separately actuating the exhaust valves using variable valve actuation, the exhaust flow is split between two manifolds, thereby reducing the overall engine backpressure and lowering pumping losses. In this paper, results from zero-dimensional and one-dimensional simulations of a multicylinder RCCI light-duty engine equipped with DEP are presented.

The use of a hydraulic drive system with accumulator energy storage has the potential of providing large gains in fuel economy of internal combustion engine passenger automobiles. The improvement occurs because of efficient regenerative braking and the practicality of decoupling the engine operation from the driving cycle demands. The concept under study uses an engine-driven pump supplying hydraulic power to individual wheel pump/motors (P/M's) and/or an accumulator. Available P/M's have high efficiencies (e.g., 95%) at the ideal point of operation, but the efficiency falls off considerably at combinations of pressure, speed, and displacement that are significantly away from ideal. In order to maximize the fuel economy of the automobile, it is necessary to provide the proper combination of components, system design, and control policies that operate the wheel P/M's as close as possible to their maximum efficiency under all types of driving and braking conditions.

Students, as members of Team Paradigm, at the University of Wisconsin-Madison have designed a charge regulating, parallel hybrid electric Dodge Intrepid for the 1997 FutureCar Challenge (FCC97). The goals for the Wisconsin “FutureCow” are to achieve an equivalent fuel consumption of 26 km/L (62 mpg) and Tier 2 Federal Emissions levels while maintaining the full passenger/cargo room, appearance, and feel of a stock Intrepid. These goals are realized through drivetrain simulations, a refined vehicle control strategy, decreased engine emissions, and aggressive weight reduction. The vehicle development has been coupled with 8,000 km of reliability and performance testing to ensure Wisconsin will be a strong competitor at the FCC97.

The University of Wisconsin - Madison Hybrid Vehicle Team has designed, fabricated, tested and optimized a four-wheel drive, charge sustaining, split-parallel hybrid-electric crossover vehicle for entry into the 2006 Challenge X competition. This multi-year project is based on a 2005 Chevrolet Equinox platform. Trade-offs in fuel economy, greenhouse gas impact (GHGI), acceleration, component packaging and consumer acceptability were weighed to establish Wisconsin's Vehicle Technical Specifications (VTS). Wisconsin's Equinox, nicknamed the Moovada, utilizes a General Motors (GM) 110 kW 1.9 L CIDI engine coupled to GM's 6-speed F40 transmission. The rear axle is powered by a 65 kW Ballard induction motor/gearbox powered from a 44-module (317 volts nominal) Johnson Controls Inc., nickel-metal hydride hybrid battery pack. It includes a newly developed proprietary battery management algorithm which broadcasts the battery's state of charge onto the CAN network.

The demand for highly flexible manipulation of plant growth generations, modification of specific plant processes, and genetically engineered crop varieties in a controlled environment has led to the development of a Commercial Plant Biotechnology Facility (CPBF). The CPBF is a quad-middeck locker playload to be mounted in the EXPRESS Rack that will be installed in the International Space Station (ISS). The CPBF integrates proven ASTROCULTURE” technologies, state-of-the-art control software, and fault tolerance and recovery technologies together to increase overall system efficiency, reliability, robustness, flexibility, and user friendliness. The CPBF provides a large plant growing volume for the support of commercial plant biotechnology studies and/or applications for long time plant research in a reduced gravity environment.

Optimal fuel injection strategies are obtained with a micro-genetic algorithm and an adaptive gradient method for a nonroad, medium-speed DI diesel engine equipped with a multi-orifice, asynchronous fuel injection system. The gradient optimization utilizes a fast-converging backtracking algorithm and an adaptive cost function which is based on the penalty method, where the penalty coefficient is increased after every line search. The micro-genetic algorithm uses parameter combinations of the best two individuals in each generation until a local convergence is achieved, and then generates a random population to continue the global search. The optimizations have been performed for a two pulse fuel injection strategy where the optimization parameters are the injection timings and the nozzle orifice diameters.

The University of Wisconsin Hybrid Vehicle Team has implemented and optimized a four-wheel drive, charge sustaining, split-parallel hybrid-electric crossover vehicle for entry into the 2008 ChallengeX competition. This four year project is based on a 2005 Chevrolet Equinox platform. Fuel economy, greenhouse gas impact (GHGI), acceleration, component packaging and consumer acceptability were appropriately weighted to determine powertrain component selections. Wisconsin's Equinox, nicknamed the Moovada, is a split-parallel hybrid utilizing a General Motors (GM) 110 kW 1.9L CDTi (common rail diesel turbo injection) engine coupled to an F40 6-speed manual transmission. The rear axle is powered by a SiemensVDO induction motor/gearbox power-limited to 65 kW by a 40-module (288 volts nominal) Johnson Controls Inc, nickel-metal hydride battery pack.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/coir fiber composites were prepared via both conventional and microcellular injection-molding processes. The surface of the hydrophilic coir fiber was modified by alkali and silane-treatment to improve its adhesion with PHBV. The morphology, thermal, and mechanical properties were investigated. The addition of coir fiber (treated and untreated) reduced cell size and increased cell density. Further decrease in cell size and increase in cell density were observed for treated fibers compared with PHBV/untreated fiber composites. Mechanical properties such as specific toughness and strain-at-break improved for both solid and microcellular specimens with the addition of coir fibers (both treated and untreated); however, the specific modulus remained essentially the same statistically while the specific strength decreased slightly.

The University of Wisconsin - Madison hybrid vehicle team has designed and constructed a four-wheel drive, charge sustaining, parallel hybrid-electric sport utility vehicle for entry into the FutureTruck 2003 competition. This is a multi-year project utilizing a 2002 4.0 liter Ford Explorer as the base vehicle. Wisconsin's FutureTruck, nicknamed the ‘Moolander’, weighs 2000 kg and includes a prototype aluminum frame. The Moolander uses a high efficiency, 1.8 liter, common rail, turbo-charged, compression ignition direct injection (CIDI) engine supplying 85 kW of peak power and an AC induction motor that provides an additional 60 kW of peak power. The 145 kW hybrid drivetrain will out-accelerate the stock V6 powertrain while producing similar emissions and drastically reducing fuel consumption. The PNGV Systems Analysis Toolkit (PSAT) model predicts a Federal Testing Procedure (FTP) combined driving cycle fuel economy of 16.05 km/L (37.8 mpg).

The University of Wisconsin - Madison FutureTruck Team has designed and built a four-wheel drive, charge sustaining, parallel hybrid-electric sport utility vehicle for entry into the FutureTruck 2001 competition. The base vehicle is a 2000 Chevrolet Suburban. Our FutureTruck is nicknamed the “Moollennium” and weighs approximately 2427 kg. The vehicle uses a high efficiency, 2.5 liter, turbo-charged, compression ignition common rail, direct-injection engine supplying approximately 104 kW of peak power and a three phase AC induction motor that provides an additional 68.5 kW of peak power. This hybrid drivetrain is an attractive alternative to the large displacement V8 drivetrain, as it provides comparable performance with lower emissions and fuel consumption. The PNGV Systems Analysis Toolkit (PSAT) model predicts a Federal Testing Procedure (FTP) urban driving cycle fuel economy of 11.24 km/L (26.43 mpg) with California Ultra Low Emission Vehicle (ULEV) emissions levels.

The University of Wisconsin - Madison FutureTruck Team has designed and built a four-wheel drive, charge sustaining, parallel hybrid-electric sport utility vehicle for entry into the FutureTruck 2002 competition. This is a two-year project with tiered goals; the base vehicle for both years is a 2002 Ford Explorer. Wisconsin's FutureTruck, nicknamed the ‘Moolander’, weighs approximately 2050 kg. The vehicle uses a high efficiency, 2.5 liter, turbo-charged, compression ignition common rail, direct-injection engine supplying approximately 100 kW of peak power and a AC induction motor that provides an additional 33 kW of peak power. This hybrid drivetrain is an attractive alternative to the large displacement V6 drivetrain, as it provides comparable performance with similar emissions and drastically reduced fuel consumption.

Recently, urgent needs have arisen for improving the fuel economy of passenger cars. To improve the fuel comsumption, it is necessary to develop a technology that can improve fuel efficiency and weight-saving. This paper describes the development of a soundproof package to balance weight-saving with performance of acoustic isolation used to reduce engine noise. First, we developed a hybrid statistical energy analysis (HSEA) model to evaluate the performance. Second, by using the HSEA model, we (1) analyzed the power flow and dominant path from noise source to interior cavity, (2) extracted efficient sections such as dash, dash penetration parts, and floor so as to improve the performance. Using the above process, we developed a soundproof package that improves the performance without increasing the weight. As a result, we balanced weight-saving with performance of acoustic isolation using the HSEA model.

A method including Multi-Body Dynamics (MBD) and fatigue assessment process with modal approach was developed to predict Light Commercial Van (LCV) Rear French Doors open/close durability performance during early design stage to improve test detect ability. The nonlinear properties of joints, such as those on bolted housings or spot welds sheets and hem flange areas, can substantially influence the local and global results of a dynamic simulation. The Modal approach considers joint contact, by way of Joint Interface Modes (JIMs) by using Contact Subroutine (MAMBA) to co-simulate with MBD software to improve result quality. One of the main challenges is measuring the dynamic stiffness for the weather strip. A novel test method was used to measure the weather strip dynamic stiffness by conducting an “in-situ” test. For CAE simulation results, positive feedback was received from design and test engineers.

This paper describes the design measures taken to develop the noise and vibration performance of a new rear suspension and a new drivetrain system for rear-wheel-drive vehicles. The new rear suspension is designed to solve trade-off issues between road noise and handling performance. Despite higher drive torque, booming noise is greatly reduced by the new rear suspension and drivetrain without increasing the vehicle weight or sacrificing fuel economy.

A hybrid system that has been put on the market by Nissan Motor Company was configured by removing the torque convertor with a lockup clutch from a conventional 7-speed automatic transmission and installing a clutch and a motor in its place. This hybrid electric vehicle (HEV) has a simple structure and is expected to improve fuel economy and responsiveness because it eliminates the torque convertor. One issue for this system is that an abrupt change in the input torque could cause torsional vibration of the drive shaft, resulting in a severe degradation of ride comfort. To solve this problem, an original vibration control system that was adapted for the mass-produced LEAF electric vehicle was also adapted for use on this HEV fitted with an engine and a 7-speed automatic transmission. This control system enables the hybrid vehicle to generate maximum motor torque at launch and also provides significant advantages for vehicle design.

A new 1.2L inline 3-cylinder supercharged gasoline engine was developed to improve fuel efficiency and to meet EURO 5 emission regulations. The engine was designed with a high compression ratio, heavy exhaust gas recirculation (EGR), and a long stroke to improve fuel efficiency. The Miller cycle and a direct fuel injection system were applied to this engine in order to mitigate the occurrence of knock due to the high compression ratio. In addition, a supercharging system was adopted to compensate for the decline in charging efficiency due to the Miller cycle. The design of a direct injection gasoline engine involves a lot of problems such as reduction of oil dilution, stabilization of combustion at first idle retarded, improvement of air-fuel mixing homogeneity, and strengthening of the gas flow. It is hard to resolve these problems independently due to their complexities and difficult nature. Reducing wall wetting by the fuel spray can improve oil dilution in a small engine.

This paper describes a new 1.2-liter three cylinder gasoline engine named HR12DDR, with the target to achieve the lowest level CO2 in the European B-segment market and also, to satisfy the customer's driving pleasure through high output performance. This engine is developed with the consideration of meeting further strict regulations in the years ahead and of the possibility of being an alternative powertrain of diesel in the future as well. As a first step this engine was applied on the European Nissan Micra in 2011; achieving 95g/km CO2 emissions(NEDC mode). This low fuel consumption was realized mainly through technologies which scope to maximize thermal efficiency with high compression ratio, and to minimize the mechanical friction loss. The combustion was optimized by Direct injection (DI)system. To obtain the better fuel economy performance without sacrificing high output, we chose the supercharger system with bypass valve and electromagnetic clutch.

Hybrid powertrain technology, which combines an internal combustion engine and an electric motor as power sources, is penetrating auto markets as a practical approach for reducing vehicle fuel consumption and exhaust emissions. This paper describes the development of an integrated powertrain simulation technology for predicting the fuel economy and exhaust emissions of hybrid electric vehicles with high accuracy and computation speed. Primary paths of kinetic, electric, chemical and thermal energies and their management were modeled. The predicted exhaust emissions and temperatures of the coolant and lubrication oil agreed well with experimental data in various vehicle driving conditions. This simulation was used to study an air-fuel ratio control strategy for reducing NOx at engine restart and to examine an exhaust heat recovery method for reducing fuel consumption and exhaust emissions under cold start conditions.