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An essential feature of the Audi Quattro permanent four-wheel drive system is in the inter-axle differential located on the hollow output shaft in the gearbox: the drive is taken from this differential forward to the front differential through the inside of the hollow shaft, and rearward to a propellor shaft driving the rear differential. The major advantages in everyday driving include improved traction and a reduced tendency toward throttle induced changes of attitude. The greater traction allows not only better progress in difficult road conditions; it also gives better acceleration in difficult traffic situations, such as when joining a busy main road. The more easily predictable handling response to throttle changes means that Quattro vehicles have better tracking stability. Altogether, the active safety and "roadability" are considerably improved.

It is well known that backpressure is one of the important parameters to be minimised during the exhaust system development. Unfortunately, during the first phases of an engineering process of a new engine, engine prototypes are not available yet. Due to this the exhaust system backpressure is generally evaluated using simulation software, and/or measuring the backpressure by a flow rig test at room temperature. Goal of this paper is to compare exhaust backpressure results obtained respectively: i) at the room temperature flow rig; ii) at the engine dyno bench; iii) by simulation with one of the most common 1D fluidodynamics simulation tool (Gt-Power). A correlation of the three different techniques is presented.

The battery cooling system is one of the most critical parts for the safe and efficient operation of the Li-ion battery pack in EVs. Battery liquid cooling system is most commonly used. This paper represents a comprehensive study of the electric vehicle battery liquid cooling system design and performance using the 1D tool and experimental validation. The 1D model includes the battery thermal load, cooling system components, and different ambient conditions. The cooling system components are calibrated using the experimental performance data of the components. The 1D model is used to evaluate the effect of fan speed, ambient temperature, compressor speed, and coolant flow rate on the battery cooling system and to optimize the component sizing. The results are then experimentally validated in a climate chamber, and the simulation results show good agreement with experimental results. The study's findings provide a good understanding of the Li-ion liquid cooling system.

Model-based software development is a well-established software development process and recognized by ISO26262 [1] as allowing for highly consistent and efficient development. Nevertheless, enhancing a model-based development process in such a way that it is compliant with the ISO26262 safety standard is a challenging task. To achieve ISO26262 compliance, the development team of a safety-related software project faces a multitude of additional requirements for the development process without a corresponding increase of the project budget to fulfill them. The fact that many of the requirements of ISO26262 are defined in a very generic way such that an interpretation is required further hampers their implementation. We propose a 10-step strategy to achieve an ISO26262 compliant model-based software development process. This strategy relates ISO26262 requirements with state-of-the art methods and approaches currently used for model-based software development.

Many automated guided golf cars using the electromagnetic guide technology are used in Japan to obtain more convenient and safer golf play. Now this technology is beginning to be used outside of the golf course as an on-demand people mover system. This paper presents an example of the engineering system of automated guided golf cars along for the 2 principles of automated guided vehicle. The first principle is “the steering control system including the automatic sensitivity adjustment function”, and the other principle is “the vehicle speed control system”.

A vehicle model is an important factor in the development of vehicle control systems. Various vehicle models having different complexities, assumptions, and limitations have been developed and applied to many different vehicle control systems. A 14 DOF vehicle model that includes a roll center as well as non-linear effects due to vehicle roll and pitch angles and unsprung mass inertias, is developed. From this model, the limitations and validity of lower order models which employ different assumptions for simplification of dynamic equations are investigated by analyzing their effect on vehicle roll response through simulation. The possible limitation of the 14 DOF model compared to an actual vehicle is also discussed.

Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.

An expansion tank is an integral part of an automotive engine cooling system. The primary function of the expansion tank is to allow the thermal expansion of the coolant. The expansion tank will be referred as hot bottle in this paper. In the System level modeling of the engine internal flow, it is imperative to accurately model and characterize the components in the system. It is often challenging to define the hot bottle accurately with limited parameters in the 1D modeling. Currently it is very difficult to optimize the system by testing. Since testing consumes a lot of time and changes in development stage. If the hot bottle component is not defined properly in the system network, then the system flow balancing cannot be predicted accurately. In this paper, the approach of creating a 1D modeling tool for hot bottle flow prediction is discussed and the simulation results are compared with the physical test data.

Advanced control techniques are widely used in different automotive applications including climate control. Significant costs associated with the development and calibration of such controllers can be reduced if these tasks are conducted in a virtual environment. Such a virtual environment can be developed by integrating the controller with the system model. Different scenarios can be then simulated to make sure functional objectives of the system are met. 1D models provide the necessary level of accuracy without imposing extra computational cost in such virtual environments. As such, they are perfect candidates for model, hardware or software-in-the loop validation benches for controls. Performance of a heating, ventilation and air-conditioning (HVAC) system can be controlled through the settings of the components like mode door, blend door, recirculation door, blower, and the compressor.

In today’s competitive scenario, the automotive product life cycle has drastically reduced and all Auto OEM’s are coming up with their updated products with lesser development time. These frequent product upgrades are possible due to use of various digital tools during product design and development. Design and optimization of engine coolpack (powertrain cooling unit) to attain engine cooling performance is one of the important parameter during vehicle development or upgrade. Hence, to keep control over development cost and time of delivery, quick and accurate digital validation capability like one dimensional (1D) simulation is the need of the hour. To predict the powertrain cooling (PTC) performance at vehicle concept stage, when physical prototypes are not available, airflow data from similar developed platforms is considered as an input for 1D simulation.

This paper discusses the methodology setup for grill opening area prediction at the early development phase of the product development lifecycle, using a commercially available 1D simulation tool- AMESIM. Representative under hood has been modeled using Grill, Condenser, Radiator, intercooler, fan, and engine components. Vehicle velocity is used as an input to derive the airflow passing through the grill and other under-hood components based on ram air coefficient, pressure drop through different components (Grill, Heat exchanger, Fan & Engine). This airflow is used to predict the top tank temperature of the radiator. Derived airflow is correlated with airflow obtained from CFD simulation. A balance has been achieved between cooling drag & fan power consumption at different grill opening areas for target top tank temperature. Top tank temperature has been predicted at two different extreme engine heat rejection operating points.

Handling performance of a vehicle is a key characteristic determining the response of vehicle under different operating scenarios. An insight into these vehicle-handling characteristics at early stage can be extremely useful in the design and development process. Tire characterization and tuning is important and mandatory to scrutinize each functional and individual parameter of tire. Tire force and moment data is having a significant effect in vehicle handling. Segregation of tire parameter, which is contributing vehicle-handling performance, helps to identify and perform optimization for improvisation. The main objective of this study is development and integration optimized 1D tire model into multibody dynamics model of the vehicle to observe various vehicle compliances towards its handling performance target.

For the thermal management of an automobile, the induced airflow becomes necessary to enable the sufficient heat transfer with ambient. In this way, the components work within the designed temperature limit. It is the engine-cooling fan that enables the induced airflow. There are two types of engine-cooling fan, one that is driven by engine itself and the other one is electrically driven. Due to ease in handling, reduced power consumption, improved emission condition, electrically operated fan is becoming increasingly popular compared to engine driven fan. The prime mover for electric engine cooling fan is DC motor. Malfunction of DC motor due to overheating will lead to engine over heat, Poor HVAC performance, overheating of other critical components in engine bay. Based upon the real world driving condition, 1D transient thermal model of engine cooling fan motor is developed. This transient model is able to predict the temperature of rotor and casing with and without holes.

Motor thermal management of electric vehicles (EVs) is becoming more significant due to its close relations to vehicle aerodynamic performance and power consumption, while computer aided engineering (CAE) plays an important role in its development. A 1D-3D coupled model is established to characterize transient thermal performance of the motor in an electric vehicle on a high performance computer (HPC) platform. The 1D motor thermal management model is integrated with the 1D powertrain model, and a 3D thermal model is established for the motor, while online data exchange is realized between the 1D and 3D models. The 1D model gives boundaries such as inlet coolant temperature, mass flowrate and motor heat generation to the 3D model, while the 3D model gives back boundaries such as heat transfer to coolant simultaneously. Transient simulations are performed for the 140kph(20°C) driving cycle, and the model is calibrated with experimental data.

This paper describes new 2 stroke fuel injected spark ignition outboard motor equipped with unique oxygen sensor feed back control system to assure constantly optimized air/fuel ratio. First, the general concept and the engineering target of commercial model are explained, and then the design and arrangement of oxygen sensor feedback fuel injection control system are described. Common automotive oxygen sensor is utilized in this system, and it is devised to overcome the problems inherent in 2-stroke engines. This paper also describes the controlled combustion system that enhances consistent and stable performance, and improves fuel efficiency. Applying these technologies, 40% less fuel consumption in cruise range was demonstrated by the comparative test with conventional fuel injected 2-stroke model.

After the first appearance of LED rear lamps, which employed mainly two-dimensional arrays of LEDs, the request of stylists and OEMs to have three-dimensional LED alignment has increased strongly. Development of more powerful LEDs and new packaging and assembly technologies now allows for a three-dimensional assembly of the LEDs, giving an impression of depth and enabling the LEDs to follow even extreme curvatures. This gives great customer satisfaction in terms of styling, but the disadvantage is that the cost for the three-dimensional LED alignment increases significantly. To counteract this development, we have developed a light guide technology approach (so-called 2.5 D) to combine a cost efficient LED assembly process with the flexibility of a 3 D arrangement of the light sources. Thus, we can use standard planar FR4 (Flame Resistant 4) LED printed circuit boards with arbitrary LEDs and do not depend on a certain assembly technology.

The 2005 Ford GT high performance sports car was designed and built in keeping with the heritage of the 1960's LeMans winning GT40 while maintaining the image of the 2002 GT40 concept vehicle. This paper reviews the technical challenges in designing and building a super car in 12 months while meeting customer expectations in performance, styling, quality and regulatory requirements. A team of dedicated and performance inspired engineers and technical specialists from Ford Motor Company Special Vehicle Teams, Research and Advanced Engineering, Mayflower Vehicle Systems, Roush Industries, Lear, and Saleen Special Vehicles was assembled and tasked with designing the production 2005 vehicle in record time.

An integrated engineering approach using computer modeling, laboratory and vehicle testing enabled the Ford GT engineering team to achieve supercar thermal management performance within the aggressive program timing. Theoretical and empirical test data was used during the design and development of the engine cooling system. The information was used to verify design assumptions and validate engineering efforts. This design approach allowed the team to define a system solution quickly and minimized the need for extensive vehicle level testing. The result of this approach was the development of an engine cooling system that adequately controls air, oil and coolant temperatures during all driving and environmental conditions.

This paper describes the engineering, manufacturing and integration necessary to produce the Corvette's first ever all-aluminum spaceframe (see Figure 1). The engineering and manufacturing of the spaceframe was a joint venture between General Motors and suppliers ALCOA (Aluminum Company of America) and Dana Corporation. ALCOA led the initial design of the spaceframe; Dana Corp led the manufacturing; General Motors' Engineering and Manufacturing groups led the integration of the assembly. The aluminum spaceframe design is modeled after the baseline steel structure of the Corvette coupe. The aluminum spaceframe reduces 140 lbs from the steel baseline and enters the plant at 285 lbs. This frame allows the 2006 Corvette Z06 to enter the market at a 3100 lbs curb weight. Aluminum casting, extruding, stamping, hydroforming, laser welding, Metal Inert Gas (MIG) welding, Self Pierce Riveting (SPR), and full spaceframe machining make up the main technologies used to produce this spaceframe.