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As the automotive industry vies to meet progressively more stringent global CO2 regulations in a cost-effective manner, electrified drive system cost and losses must be reduced. To this end, a parametric Drive Unit (DU) mechanical-loss model was developed to aid in the design and development of electrified propulsion systems, where the total propulsion system cost and DU losses can be directly linked (e.g., Hybrid Electric Vehicle (HEV) motor/inverter/engine content, or Battery Electric Vehicle (BEV) battery size). Many DUs for electrified propulsion systems are relatively “simple” drive systems, consisting of gears, bearings, shafts, lip seals, and an electric motor(s), but without clutches, high-pressure lube systems, or chains/belts as found in conventional automatic transmissions. The DU loss model described in this paper studies these simple DUs, with the mechanical losses dissected into 10 loss components.

This paper deals with the relationship between powertrain design and the requirements resulting from connected and automated driving. The questions addressed are how much powertrain design will change in regard to automated and connected driving and which powertrain in an automated vehicle will prove to be the optimum solution. To this end, a concept study is being conducted for a D-segment vehicle and multiple powertrain topologies ranging from non-electrified, mild-hybrids to plug-in hybrids and battery electric vehicles. The development processes required to address this issue is presented accordingly, as well as the necessary methods for systemic drive optimization, taking into account all requirements of the vehicle, the drive system and the components and their interactions with each other. The requirements resulting from connected and automated driving as well as their influences on vehicle and drive concepts are elaborated.

Tula’s Dynamic Skip Fire (DSF®) technology combines highly responsive torque control with cylinder deactivation to optimize fuel consumption of spark ignited engines. Through careful control of individual combustion events, engine operation occurs at peak efficiency over the full range of torque demand. A challenge with skip-fire operation is avoiding objectionable noise and vibration. Tula’s DSF technology uses sophisticated firing control algorithms which manage the skip-fire sequence to avoid excitation of the powertrain and vehicle at sensitive frequencies. DSF enables a production-quality driving experience while reducing CO2 emissions by 8-15% with no impact on regulated toxic emissions. Moreover, DSF presents a high value solution for meeting global emissions mandates, with estimated cost less than $40 per percent gain in fuel efficiency.

Current industry trends in both powertrain electrification and vehicle drag reduction point towards reduced peak and average power demands from the internal combustion engine in future long-haul class 8 vehicles. Downsizing the engine displacement to match these new performance requirements can yield a benefit in drive cycle efficiency through reduced friction and improved cruise load efficiency. Downsizing by reducing cylinder count avoids the heat loss and friction penalties from reduced per-cylinder displacement and could allow a manufacturer to continue to leverage the highly optimized combustion system from existing heavy-duty engines in the new downsized offering. The concept of this study is to leverage powertrain electrification and the improvement trends in vehicle aerodynamics and rolling resistance to develop a fuel economy focused, downsized heavy duty diesel powertrain for future long-haul vehicles utilizing a reduced cylinder count.

What will the passenger car fleet look like over the next two decades' As most expected, affordability and convenience are the major drivers of new vehicle technology penetration into the market. Within this scope, vehicle electrification strategy to limit oil dependence and meet the European targets for CO₂ emissions should be cost-effective and convenient to the buyer. This paper will focus first, through different economic models, on the penetration of passenger electrified vehicles (Plug-in Hybrid Vehicles PHVs and Electric Vehicles EVs) in Europe (EU15: 15 European Union member countries) up to 2030. Economic models are based on real-world-use behaviors and driving patterns in order to compute fuel and energy consumption and to estimate total cost of the vehicle including incentives. The economic models use household wages in order to later make conclusions on vehicle technology market shares by vehicle classes.

This paper discusses some of the key issues that policy would need to address to effectively encourage significant innovation in hybrid electric vehicle technologies. Emphasis is placed in related provisions in the Energy Independence and Security Act of 2007, as the energy legislation that authorizes (though appropriations have not occurred yet) the allocation of public resources to vehicle technology programs. Private investment in vehicle hybridization is contingent on expectations about future oil prices, which in turn are highly uncertain. The importance of addressing this issue in the context of technology innovation policy is discussed.

A car contained automotive speed control system is described. Electrical signals generated by a speedometer operated switch are amplified by a transistor controlling a solenoid valve. This valve modulates manifold vacuum supply to a diaphragm which controls the engine throttle, maintaining a precisely preselected speed. Components and system operation are outlined, with a description of driver operated controls and circuitry. The AC Electro-Cruise concept has resulted in a constan speed throttle control which can be economically produced to fill today's super highway cruising needs. There is considerable design flexibility for adapting to the individual desires of various car manufacturers and for filling future needs.

Electro emissive devices, called ESTHER, are thin sheets - similar to solar cells - whose infrared emissivity can be varied reversibely by electrical charging. Bonded to external surfaces of spacecraft radiators, they allow active control of the heat radiated to space while consuming negligible electrical energy. Applying this novel component for spacecraft thermal control, considerable cost savings in spacecraft development and operation can be achieved. Progress in the design and manufacturing process has been made since the first puplication in July '92 /1/ revealing an increased variability of emissivity and an increased duty cycle stability. The material selection process was facilitated by the exposure of material samples to the space environment during two spaceflight missions and the subsequent material analyses.

Visteon Automotive Systems has developed an Electro-Hydraulic Power Assist Steering (EHPAS) System. This low-cost system uses conventional hydraulic power steering components with an electrically-driven and electronically-controlled power steering pump. This paper presents the Visteon EHPAS system and its development process. This process began with analytical modeling of the EHPAS system and integration of these models with a two degree of freedom (2DOF) vehicle model. These models were critical for system analysis and control strategy design. The EHPAS system sizing procedure and control strategy performance optimization were verified with the use of a real-time computer designed by Ford Motor Company, and by specially-designed Visteon test benches. Finally, EHPAS equipped test vehicles were tuned for high performance, providing better feel and fuel economy than conventionally equipped base line vehicles.

The first step toward a braking system ‘by wire’ is Electro-Hydraulic Braking System (EHB). The paper describes a method to evaluate through virtual experimentation the actual improvement in vehicle behaviour, from the point of view of both handling and comfort, including also pedal feeling, due to EHB. The first step consisted in modelling the hydraulic unit, comprehensive of sensors. Then it was conceived a control logic devoted to medium-low intensity braking manoeuvres, without ABS intervention, to determine an optimal braking force distribution and pedal feeling depending on the manoeuvre. A failsafe strategy, complete of on board diagnosis, to prevent dangerous system behaviour in the eventuality of a component failure was carried out and tested. Finally, EHB wheel pressure sensors were used to improve both ABS performance, increasing the adherence estimation, and Vehicle Dynamics Control (VDC) performance, through a more precise actuation.

With the development of brake-by-wire technology, electro-hydraulic composite braking technology came into being. This technology distributes the total braking force demand into motor regenerative braking force and hydraulic braking force, and can achieve a high energy recovery rate. The existing composite braking control belongs to single-channel control, i.e., the four wheel braking pressures are always the same, so the hydraulic braking force distribution relationship of the front and rear wheels does not change. For single-axle-driven electric vehicles, the additional regenerative braking force on the driven wheels will destroy the original braking force distribution relationship, resulting in reduced braking efficiency of the driven wheels, which are much easier to lock under poor road adhesion conditions.

Recently, 5-speed automatic transmissions have become mainstream through the world, and 6-speed automatic transmissions have also been introduced in the market. Consequently, the issue of shift control is gaining importance, and a trend toward increasing number of gears in automatic transmissions has become apparent. On the other hand, weight saving and downsizing of the transmission, including the hydraulic control unit, are strongly required in order to promote fuel efficiency. To meet these requirements, an electro-hydraulic control unit offering sophisticated functionality desired in order to provide excellent shift quality. As an answer to these requirements AISIN AW developed two types of new 6-speed automatic transmissions in 2002: “TR-60SN” for RWD vehicles and “TF-60SN” for FWD vehicles. Both TR-60SN and TF-60SN have the same structural characteristics.

Combine electro-hydraulic header height control systems have been widely accepted. Conventional on-off solenoid valves, however, perform less than ideally in automatic header height control systems due to their lack of metering. More acceptable automatic mode performance can be achieved with two stage valving, with a controlled response solenoid valve, or using a proportional valve. Electro-hydraulic proportional flow limiters provide smooth, repeatable flow control for combine hydraulic reel drives. Manual control options include a rheostat, a stepped resistance switch, or a pulse width modulated circuit. Automatic correlation of reel speed to ground speed is achieved with a closed loop or open loop electronic system.

This paper describes a new technology of an electronically controlled transmission for mid-size agricultural tractors. The most notable feature is a electro hydraulically controlled wet multi-disk clutch that is employed to change transmission speeds. This clutch provides for continuous, smooth speed changes regardless of load. The speed change is accomplished by three steps of control: 1) overlap control where the pressure applied to the hydraulic clutch is overlapped, 2) load detection control where the load is determined by monitoring the engine rpm and the governor setting, and 3) shock reduction control where the hydraulic clutch pressure is reduced according to the load.

A controller for a three point hitch is described. It includes five separate states which govern the operation and performance of the hitch. The control objective in each state is explained in detail. The actual transitions between the states, which are controlled based on external events, are given via a transition table and some examples. Such transitions are triggered by both; the operator and, in certain circumstances, by the conditions of the soil, tractor speed, etc. The controller is designed to allow adapting it to various tractors under different types of loading conditions, hydraulic cylinder volumes, and options available on the tractor. Controller operation is also adjusted based on battery voltage as well as the electro-hydraulic valve coil resistance. Failures, which are being continuously searched for, are divided into four categories which manipulate and modify the performance of the hitch.

Vehicle responsiveness to the driver's steering maneuvers and external turbulences caused by irregularities in the road surface and wind gusts are two opposing factors to be studied for better stability and controllability of vehicles. The cruising speeds of vehicles on freeways have been becoming higher, and wider physiological differences in the driving ability of drivers are appearing with the increase in elderly drivers. Therefore, to meet the requirements of higher cruising speeds and the expanding physiological differences between drivers, an electro-hydraulic feedforward control power steering system has been developed for trucks and buses. This is a parallel operating system consisting of a mechanical route and an electronic route, and improves vehicle responsiveness so as to absorb the physiological differences of drivers.

Fully Flexible Valve Actuation (FFVA) systems provide maximum flexibility to adjust lift profiles of engine intake and exhaust valves. A research grade electro-hydraulic servo valve based FFVA system was designed to be used with an engine in a test cell to precisely follow desired lift profiles. Repetitive control was chosen as the control strategy. Crank angle instead of time is used to trigger execution to ensure repeatability. A single control is used for different engine speeds even though the period for one revolution changes with engine speeds. The paper also discusses lift profile extension, instantaneous lift profile switching capability and built-in safety features.

A new control system for combine harvesters has been developed allowing vertical and lateral header control both above and on the ground. A further characteristic of this new control system is its active oscillation damping during transport with header installed. Above-ground header control with programmable stubble height operates without contact. The ground clearance is measured using ultrasonic sensors with adaptive signal filtering in order to distinguish ground signals from crop signals. The ground pressure is controlled by reference to the measured pressure in the hydraulic lift cylinder. A high-resolution pressure sensor continually measures the residual weight of the header. The pressure signal in the lift cylinder is also used for active oscillation damping of the combine harvester's pitching motion.

This paper introduces two new types of basic components (an Electro-Hydraulic Tube and a Hydraulic Tube) which when connected in an appropriate manner can control flow and pressure for many applications; in addition, one of the devices is readily interfacable to a microprocessor for external control. Some background information about the basic concept and the operation of the two components is introduced. Some of the experimental characteristics will be illustrated and several basic circuit examples will be presented to show how the concept can be implemented. The Electro-Hydraulic Integrated Block (EHIB) and Circuit (EHIC) will be introduced followed by a discussion of the advantages and potential of the EHIC concept.

Use of the electro-hydraulic effect for metal forming is one of the significant advances in the high-energy-rate field. The Cincinnati Electroshape method of converting electrical energy to hydraulic energy by discharging a high voltage spark across a transducer under water provides new production capability. This paper describes the Electroshape and discusses how new transducer developments provide an economic manufacturing method. Specific parts and related tooling problems are presented. Economic application of the electro-hydraulic effect to various parts and production rates are considered. The possibility of new quality standards and increased design flexibility are discussed.