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Fuel economy of two-wheelers is an important factor influencing the purchasing psychology of the consumer within the emerging markets. Additionally, air pollution being a major environmental topic, there is a rising concern about vehicle emissions, especially in the big cities and their metropolitan areas. Potentially, the relatively expensive engine management systems are providing more features and value in comparison to the carburettor counterpart. The combustion system analysis is carried out on a 125 cm3 motorcycle engine and the subsequent numerical simulation comparing the carburettor and the Electronic (Port) Fuel Injection which provides a basis to establish the fuel consumption benefit for the electronic injection systems [1].

The peak efficiency of modern spark ignited engines varies from 36% to 40% depending on the exact technology utilized. Most engines can achieve this peak efficiency for a limited operating region. Multi-speed transmissions allow the engine to operate closer to its most efficient operating regions for more significant portions of operation. In the case of hybrid powertrains, electric machines help in improving engine efficiency by adjusting operating speed and load. Engine shutdown during idle events and low loads is another avenue for improving the overall efficiency. The choice of the ideal powertrain and component sizes depends on the engine characteristics, drive cycles and vehicle technical requirements. This study examines what type of powertrains will be suitable for more efficient engines that are likely to be available in the near future. Some of the new technologies achieve higher efficiency with a trade off on power or by accepting a more restrictive operating region.

The first commercially available Plug-In Hybrid Electric Vehicle (PHEV), the General Motors (GM) Volt, was introduced into the market in December 2010. The Volt's powertrain architecture provides four modes of operation, including two that are unique and maximize the Volt's efficiency and performance. The electric transaxle has been specially designed to enable patented operating modes both to improve the electric driving range when operating as a battery electric vehicle and to reduce fuel consumption when extending the range by operating with an internal combustion engine (ICE). However, details on the vehicle control strategy are not widely available because the supervisory control algorithm is proprietary. Since it is not possible to analyze the control without vehicle test data obtained from a well-designed Design-of-Experiment (DoE), a highly instrumented GM Volt, including thermal sensors, was tested at Argonne National Laboratory's Advanced Powertrain Research Facility (APRF).

By using a radio frequency (RF) audio distortion measurement test setup, communication devices can be evaluated for degradation caused by electromagnetic interference (EMI) from active vehicle components. This measurement technique can be used to determine the performance of a radio receiver under a variety of conditions. The test setup consists of making measurements on a baseband audio signal that is sent to the device under test (receiver) via over-the-air RF transmissions. Once a baseline is established, active components on the vehicle can be powered on to determine their contribution to the receiver's degradation. The degradation measured is a result of distortion caused by conducted, radiated, and/or coupled EMI from active components into the receiver's passband.

When considering the addition of radio frequency reception and transmission equipment to the suite of electronics already installed on a modern motor vehicle, numerous issues must be considered and tested to ensure reliable and safe operation not only of the additional equipment but the vehicle itself. This paper addresses some of the major issues and suggests modest design and testing practices that will accomplish the desired reliability and safety. The modest design and testing proposed addresses good engineering practices of electrically bonding metallic surfaces of the vehicle, grounding equipment, shielding signal cables, introducing filters, and appropriately separating cables into bundles.

A new physical layer for automobile class B communication networks is based on simple galvanic connections. Only ten passive external components per node are needed to perform reliable data transmission inside the hostile car environment. Every single fault related to the bus will be detected and diagnosed by every node, where a software controlled logic assures continuous data flow.

Detailed diesel particulates morphology, nanostructures, fractal geometry, and nitrogen oxides (NOx) emissions were analyzed for five different test fuels in a 1.7-L, common-rail direct-injection diesel engine. The accurately formulated fuels permit the effects of sulfur, paraffins, aromatics, and naphthene concentrations to be determined. A novel thermophoretic sampling technique was used to collect particulates immediately after the exhaust valves. The morphology and nanostructures of particulate samples were examined, imaged with a high-resolution transmission electron microscope (HRTEM), and quantitatively analyzed with customized digital image processing/data acquisition systems. The results show that the particle sizes and the total mass of particulate matter (PM) emissions correlate most strongly with the fuels' aromatics and sulfur content.

A multimode transmission combines several power-split modes and possibly several fixed gear modes, thanks to complex arrangements of planetary gearsets, clutches and electric motors. Coupled to a battery, it can be used in a highly flexible hybrid configuration, which is especially practical for larger cars. The Chevrolet Tahoe Hybrid is the first light-duty vehicle featuring such a system. This paper introduces the use of a high-level vehicle controller based on instantaneous optimization to select the most appropriate mode for minimizing fuel consumption under a broad range of vehicle operating conditions. The control uses partial optimization: the engine ON/OFF and the battery power demand regulating the battery state-of-charge are decided by a rule-based logic; the transmission mode as well as the operating points are chosen by an instantaneous optimization module that aims at minimizing the fuel consumption at each time step.

This paper covers the development of a closed loop transaxle synchronization algorithm which was a key deliverable in the control system design for the L3 Enigma, a Battery Dominant Hybrid Electric Vehicle. Background information is provided to help the reader understand the history that lead to this unique solution of the input and output shaft synchronizing that typically takes place in a manual vehicle transmission or transaxle when shifting into a gear from another or into a gear from neutral when at speed. The algorithm stability is discussed as it applies to system stability and how stability impacts the speed at which a shift can take place. Results are simulated in The MathWorks Simulink programming environment and show how traction motor technology can be used to efficiently solve what is often a machine design issue. The vehicle test bed to which this research is applied is a parallel biodiesel hybrid electric vehicle called the Enigma.

In order to determine the factors that affect fuel economy quantitatively, the power flows through the major powertrain components were measured during operation over transient cycles. The fuel consumption rate and torque and speed of the engine output and axle shafts were measured to assess the power flows in a vehicle with a CVT. The measured power flows were converted to energy loss for each component to get the efficiency. Tests were done at Phase 1 and Phase 3 of the FTP and for two different CVT shift modes. The measured energy distributions were compared with those from the ADVISOR simulation and to results from the PNGV study. For both the Hot 505 and the Cold 505, and for both shift modes, the major powertrain loss occurs in the engine, including or excluding standby losses. However, the efficiency of the drivetrain/transmission is important because it influences the efficiency of the engine.

Connecting microcontrollers, sensors and actuators by several communication systems is state of the art within the electronic architectures of modern vehicles. The communication among these components is widely based on the event triggered communication on the Controller-Area-Network (CAN) protocol. The arbitrating mechanism of this protocol ensures that all messages are transferred according to the priority of their identifiers and that the message with the highest priority will not be disturbed. In the future some mission critical subnetworks within the upcoming generations of vehicle systems, e.g. x-by-wire systems (xbws), will additionally require deterministic behavior in communication during service. Even at maximum bus load, the transmission of all safety related messages must be guaranteed. Moreover it must be possible to determine the point of time when the message will be transmitted with high precision.

A thermophoretic particulate sampling device was used to investigate the detailed morphology and microstructure of diesel particulates at various engine-operating conditions. A 75 HP Caterpillar single-cylinder direct-injection diesel engine was operated to sample particulate matter from the high-temperature exhaust stream. The morphology and microstructure of the collected diesel particulates were analyzed using a high-resolution transmission electron microscope and subsequent image processing/data acquisition system. The analysis revealed that spherical primary particles were agglomerated together to form large aggregate clusters for most of engine speed and load conditions. Measured primary particle sizes ranged from 34.4 to 28.5 nm at various engine-operating conditions. The smaller primary particles observed at high engine-operating conditions were believed to be caused by particle oxidation at the high combustion temperature.

This work details two approaches for evaluating transmission warming technology: experimental dynamometer testing and development of a simplified transmission efficiency model to quantify effects under varied real world ambient and driving conditions. Two vehicles were used for this investigation: a 2013 Ford Taurus and a highly instrumented 2011 Ford Fusion (Taurus and Fusion). The Taurus included a production transmission warming system and was tested over hot and cold ambient temperatures with the transmission warming system enabled and disabled. A robot driver was used to minimize driver variability and increase repeatability. Additionally the instrumented Fusion was tested cold and with the transmission pre-heated prior to completing the test cycles. These data were used to develop a simplified thermally responsive transmission model to estimate effects of transmission warming in real world conditions.

Detailed characteristics of morphology, nanostructures, and sizes were analyzed for particulate matter (PM) emissions from low-temperature combustion (LTC) modes of a single-cylinder, light-duty diesel engine. The LTC engines have been widely studied in an effort to achieve high combustion efficiency and low exhaust emissions. Recent reports indicate that the number of nucleation mode particles increased in a broad engine operating range, which implies a negative impact on future PM emissions regulations in terms of the nanoparticle number. However, the size measurement of solid carbon particles by commercial instruments is indeed controversial due to the contribution of volatile organics to small nanoparticles. In this work, an LTC engine was operated with various biofuel blends, such as blends (B20) of soy bean oil (soy methyl ester, SME20) and palm oil (palm methyl ester, PME20), as well as an ultra-low-sulfur diesel fuel.

Detailed characteristics of particulate matter (PM) from a gasoline-direct-injection (GDI) engine were analyzed in terms of primary and aggregate particle sizes, morphology, and nanostructures. For the work, PM was collected from exhaust streams of the engine on transmission electron microscope (TEM) grids by using a thermophoretic sampler. To evaluate the effects of engine load and speed on the properties of PM, the engine was operated at loads of 25, 50, and 75% at 1500 and 3000 rpm. In addition, the effects of fuel injection timing on the PM were examined for samples subjected to injection timings of 190, 230, 260, 300 and 330° bTDC at the constant engine load (50% load) and speed (1500 rpm). The results showed that with advancing injection timing, average primary and aggregate particle sizes gradually increased, which implies that fuel-air mixing is a crucial factor influencing particle size.

Electronic control systems for automatic transmissions have been gaming acceptance in recent years Besides the various types of sensors already in use [for speed, temperature, pressure etc], electro-hydraulic actuators and electronic control units [ECU] are also major constituents of modern control systems Former designs utilized discrete components which were wired together In the interim, actuator modules have been developed for use in new transmission designs As well as presenting actuator concepts, this paper describes a highly integrated and advanced control module This module consists of hydraulic actuators, pilot-solenoid values and an electronic control unit which has been realized in multi-layer hybrid technology

The electrification of the powertrain, the diversity and the complexity of the more or less individual technical solutions which are preferred by different car manufacturers, create a steadily increasing challenge for the whole automotive industry. Missing standards and sales volumes still below the market expectations on the one hand, and the increasing interaction of the main powertrain domains (engine, transmission, e-drive) caused by upcoming cross domain functions on the other hand, lead to increasing development costs and non-optimal solutions concerning fuel economy improvement. Within the domain of engine management systems Bosch established in the mid-nineties the so called torque structure as the solution to a similar situation addressing the coordination of air management, fuel injection and ignition.

Argonne National Laboratory (ANL) researchers have embarked on an ambitious program to quantitatively demonstrate the potential of hydrogen as a fuel for internal combustion engines (ICEs) in hybrid-electric vehicle applications. In this initiative, ANL researchers need to investigate different hybrid configurations, different levels of hybridization, and different control strategies to evaluate their impacts on the potential of hydrogen ICEs in a hybrid system. Because of limitations in the choice of motor and battery hardware, a common practice is to fix the size of the battery and motor, depending on the hybrid configuration (starter/alternator, mild hybrid, or full hybrid) and to tune the system control for the above-available electrical power/energy. ANL has developed a unique, flexible, Hardware-In-the-Loop (HIL) platform for advanced powertrain technology evaluation: The Mobile Advanced Technology Testbed (MATT).

The particulate matter (PM) produced from a diesel engine-simulating combustor was characterized in its morphology, microstructure, and fractal geometry by using a unique thermophoretic sampling and Transmission Electron Microscopy (TEM) system. These results revealed that diesel PM produced from the laboratory-scale burner showed similar morphological characteristics to the particulates produced from diesel engines. The flame air/fuel ratio and the particulate temperature history have significant influences on both particle size and fractal geometry. The primary particle sizes were measured to be 14.7 nm and 14.8 nm under stoichiometric and fuel-rich flame conditions, respectively. These primary particle sizes are smaller than those produced from diesel engines. The radii of gyration for the aggregate particles were 83.8 nm and 47.5 nm under these two flame conditions.

The Center for Transportation Research (CTR) Vehicle Systems team modified a Nissan CK-2 Continuously Variable Transmission (CVT) for a diesel hybrid powertrain application. Mechanical and electrical modifications were made to the CVT, both internal and external to the transmission. The goal of this experiment was to investigate and demonstrate the potential of CVT for diesel engines hybrid electric vehicles (HEVs) in fuel economy and emissions. The test set-up consisted of a diesel engine coupled to an electric motor driving a Continuously Variable Transmission (CVT). This hybrid drive is connected to a dynamometer and a DC electrical power source creating a vehicle context by combining advanced computer models and emulation techniques. The experiment focuses on the impact particular transmission control strategies have on measured fuel economy and emissions specifically, nitrogen oxides (NOx) and particulate matter (PM).