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A simulation technology has been developed to enable prediction of galvanic corrosion in chassis parts where two different materials, iron and aluminum, come into contact with each other. When polarization curves representing a corrosive environment are input, this simulation technology calculates the corrosion current to flow and outputs the volume of aluminum corrosion to be formed near the iron-aluminum interface. The simulation makes it possible to predict the depth of corrosion that may occur in automobiles in the market.

Honda has developed an “Independent Left and Right Rear Toe Control System” that can achieve stable cornering performance and agile handling. We believe the issue that should be resolved in the next generation of ESC is the expansion of stability and agility into the general operation area. We examined how to accomplish this aim, and control of the independent rear toe angle was decided to be an appropriate method. In addition, a method for mounting the system without using a dedicated suspension was proposed. If left and right toe angles can be controlled independently, toe angle control and normal 4WS control become possible at the same time. In this paper, we will discuss the fundamental principle of independent toe angle control and the system configuration. Also, “INOMAMA Handling” (at driver's will) achieved by this system, as well as the fun and safe driving that are achieved as a result will be shown.

Systems engineering is not a new discipline for todays automotive OEMs and suppliers. So, why is it that many feel the discipline is under-utilized or not utilized at all in main-stream product development? For those that do believe systems engineering is a key activity in the development cycle, why is it common to disagree on a definition of what it is or how it manifests itself in the development cycle? If we examine the development activity of leading OEM's and suppliers in any industry, there can be no doubt that product development is a complex and intensive activity. Many disciplines are utilized with many specialized skills deployed throughout the lifecycle of the typical product, and even more so in the automotive industry. One can point to several processes that seem to indicate the presence of systems engineering, yet the ability to clearly define whether or not - and to what degree - we leverage systems engineering is still difficult.

Designing a lightweight and durable engine is universally important from the standpoints of fuel economy, vehicle dynamics and cost. However, it is challenging to theoretically find an optimal solution which meets both requirements in products such as the cylinder head, to which various thermal loads and mechanical loads are simultaneously applied. In our research, we focused on “non-parametric optimization” and attempted to establish a new design approach derived from the weight reduction of a cylinder head. Our optimization process consists of topology optimization and shape optimization. In the topology optimization process, we explored an optimal structure with the theoretically-highest stiffness in the given design space. This is to provide an efficient structure for pursuing both lightweight and durable characteristics in the subsequent shape optimization process.

In this research, a three degree-of-freedom (DOF) rack-type electric-based power steering (EPS) model is developed. The model is coupled with a three DOF vehicle model and includes EPS maps as well as non-linear attributes such as vibration and friction characteristics of the steering system. The model is simulated using Matlab's Simulink. The vibration levels are quantified using on-vehicle straight-line test data where strain-gauge transducers are placed in the tie-rod ends. Full vehicle kinematic and compliance tests are used to verify the total steering system stiffness levels. Frequency response tests are used to adjust tire cornering stiffness levels as well as the tire dynamic characteristics such that vehicle static gain and yaw natural frequency are achieved. On-center discrete sinusoidal on-vehicle tests are used to further validate the model.

Recently vehicle development timeline is becoming shorter, so there is an urgent need to be able to develop vehicles with limited resources. This means the efficiency of the body structure development process must be improved. Specifically it is important to reduce the amount of design re-work required to meet performance targets as this can have a large influence on the body development time. In order to reduce the afore mentioned design re-work, we developed simple calculation models to apply a “V-Flow Development Process” to the preliminary stage design of the automobile body structure. The “V-Flow” advantages are as follows: (1) simple and easy to use, (2) defects are found at early stage, (3) avoids the downward flow of the defects. The advantage of preliminary stage design is that there is design flexibility since not many specifications have been determined yet.

The development and calibration of stress state-dependent failure criteria for advanced high-strength steel (AHSS) and aluminum alloys requires characterization under proportional loading conditions. Traditional tests to construct a forming limit diagram (FLD), such as Marciniak or Nakazima tests, are based upon identifying the onset of strain localization or a tensile instability (neck). However, the onset of localization is strongly dependent on the through-thickness strain gradient that can delay or suppress the formation of a tensile instability so that cracking may occur before localization. As a result, the material fracture limit becomes the effective forming limit in deformation modes with severe through-thickness strain gradients, and this is not considered in the traditional FLD. In this study, a novel bending test apparatus was developed based upon the VDA 238-100 specification to characterize fracture in plane strain bending using digital image correlation (DIC).

This study developed technology for simultaneously welding heterogeneous resin tubes in order to weld and integrate resin tubes with two different specifications (low temperature and high temperature). The aim of integration was cost and weight reduction. The cost reduction due to reducing the number of parts exceeded the increase in material cost due to a change to resin materials. Base material fracture of the resin tubes was set as the breaking format condition, and the welding parameters of the joint part rotations and the friction time between the joint part and the resin tubes were specified as the weld strength judgment standard. In addition, the fused thickness determined by observing the cross-section after welding was specified as the weld quality judgment standard. The range over which weld boundary peeling does not occur and weld strength is manifest was clarified by controlling the welding parameters and the fused thickness.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 8 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. J2578 is currently being updated to clarify and update requirements so that it will continue to be relevant and useful in the future. An update to SAE J1766 for post-crash electrical safety was also published to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to revising SAE J2578 and J1766, the Working Group is also developing a new Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

Acoustic comfort of automotive cabins has progressively become one of the key attributes of passenger comfort within vehicle design. Wind noise and the heating, ventilation, and air conditioning (HVAC) system noise are two of the key contributors to noise levels heard inside the car. The increasing prevalence of hybrid technologies and electrification has an associated reduction in powertrain noise levels. As such, the industry has seen an increasing focus on understanding and minimizing HVAC noise, as it is a main source of noise in the cabin particularly when the vehicle is stationary. The complex turbulent flow path through the ducts, combined with acoustic resonances can potentially lead to significant noise generation, both broadband and tonal.

In use cars often drive through the wakes of other vehicles. It has long been appreciated that this imposes a fluctuating onset flow which can excite a structural response in vehicle panels, particularly the bonnet. This structure must be designed to be robust to such excitation to guarantee structural integrity and maintain customer expectations of quality. As we move towards autonomous vehicles and exploit platoons for drag reduction, this onset flow condition merits further attention. The work reported here comprises both measurements and simulation capturing the unsteady pressure distribution over the bonnet of an SUV following a similar vehicle at high speed and in relatively close proximity. Measurements were taken during track testing and include 48 static measurement locations distributed over the bonnet where the unsteady static pressures were recorded.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 10 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards associated with the integration of hydrogen and electrical systems onto the vehicle and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. An update to SAE J1766 for post-crash electrical safety was also published in 2008 to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to SAE J2578 and J1766, the SAE FCV Safety Working Group also developed a Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

Never in the history of the automotive industry has it been more critical for automakers to prove that they are capable of producing vehicles efficiently and cost-effectively. In the coming months and years there will be a growing requirement for lean product design and manufacturing strategies that will re-shape the way the automotive suppliers and OEMs conduct business. Computer-aided-design and manufacturing have become commonplace in automotive product design and manufacturing processes. These technologies enable efficiencies and quality improvements through virtual simulation and testing of kinematic designs. However, to date, there has been no ability to incorporate the process controls into these simulations. Vehicle introductions require new manufacturing processes and equipment which is typically outsourced by the OEMs to a supplier.

The CAE method to predict the vibration transfer function of the hydraulic engine mount on a vehicle with sufficient precision and calculation time without prototype cars was developed. The transfer function is given in the following steps. First, rubber deformation form under the power train weight loaded must be predicted. It’s obtained by using a reduction model of an engine mount, as a unit, which doesn’t have its fluid sealed inside, with the technique to get the static spring characteristics in a non-linear relationship. Second, Young’s modulus and structural damping coefficient for the deformed rubber must be given. As for these characteristics, ignoring the relations between these values and strain, the constant values are used. This considerably reduces computation time and model size. Next, the reduction model and the fluid model have must be combined to express actual product. In this step, coupled analysis for fluid and structure is used.

Thermal management on aircraft has been an important discipline for several decades. However, with the recent generations of high performance aircraft, thermal management has evolved more and more into a critical performance and capability constraint on the whole aircraft level. Fuel continues to be the most important heat sink on high performance aircraft, and consequently the requirements on thermal models of fuel systems are expanding. As the scope of modeling and simulation is widened in general, it is not meaningful to introduce a new isolated modeling and simulation capability. Instead, thermal models must be derived from existing model assets and eventually enable integration across several physical domains. This paper describes such an integrated approach based on the Modelica Fuel System Library and the 3DExperience Platform.

Today's engineers must meet program management demands within the context of the challenges facing the industry as a whole. Resource scarcity, both people and capital, is forcing the automotive industry to optimize the deployment and consumption of enterprise resources. As globally dispersed project teams become more commonplace, efficient and effective communication across geographies is critical. Market segmentation and technology are influencing how well manufacturers deliver products within performance and timing guidelines. Future success means providing global engineering teams with state- of- the- art tools and processes to unify disparate business groups in a virtual workspace -24/7. The solution to this is Product Lifecycle Management (PLM), a strategic business approach that supports collaborative creation across the enterprise and all stakeholders. PLM solutions link information from different authoring tools and others systems to the developing product configuration.

Mechatronics development continues to be a challenge for automotive OEM's and suppliers. Multi-disciplinary collaboration and development is critical, especially as architectures and solutions evolve in the automotive industry to satisfy changing needs of the customer and environment. New approaches to mobility, sustainment, and infotainment create the need for new combinations of electrical, software, mechanical, and chemical know-how. Whereas most frameworks for requirements-driven model-based design support a single discipline, what is really needed is a framework for requirements-driven model- based design that can capture the multi-disciplinary architecture of the vehicle or system. This would and allow development organizations to then further decompose the objects in support of further refinement and validation.

The Aerospace and Automotive industries face increasing product complexity and shortening of product development cycles. One critical means companies in these industries strive to directly overcome these challenges is through modeling and simulation. Beginning at the earliest phases in the new product development process, companies derive additional value through increased deployment of simulation across the entire product life-cycle. This paper discusses three areas: 1) the business case for change; 2) technology enablement of the various types of model-based simulators; 3) institutional mobilization to move to a new enterprise state that embraces new ways of working and engaging with existing and prospective customers. The business case for change focuses on two main points in acquisition: developing a detailed understanding of the system needs and systematically working through the techno-economic estimation challenges.

To increase sales and market position, automotive OEMs must have comprehensive strategies for developing innovative products while continuing to reduce costs, increase quality and accelerate time to market. One of the strategies that can help them to achieve these objectives is strategic modularity. A modularization strategy can help automakers reduce cost and time to market, as well as improve quality and launch readiness. While a significant number of OEMs are adopting modularity strategies, the realization of benefits has been, for many OEMs, limited in scope and scale. These limitations are due to: Process issues in managing dependencies across multiple programs and platforms; Measurements which discourage modularity adoption, together with an inability to measure enterprise costs; Organizational issues associated with siloed structures, a lack of clear roles and responsibilities, and the management of disparate groups across the extended enterprise.