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For energy saving and global warming prevention, Toyota has developed Toyota Hybrid System (THS) for mass-produced passenger cars, which achieves drastic improvement in fuel efficiency and reduction in exhaust emissions compared to conventional gasoline engine cars. The THS has two motive power sources which engage depending on driving conditions. It's power is supplied either from an engine (controlled by the engine ECU) or an electric motor (controlled by the motor ECU) which is powered by a high-voltage battery (monitored by the battery ECU). These ECUs are controlled by a hybrid ECU. Each ECU has been developed with a fail-safe system in mind, to ensure driver safety in case of vehicle breakdowns. Among these ECUs, this paper reports particularly on the newly introduced ECUs: hybrid ECU and battery ECU. In the development of these ECUs, special attention was focused on fail-safe performance.

EU legislation provides for only local CO2 emission-free vehicles to be allowed in individual passenger transport by 2035. In addition, the directive provides for fuels from renewable sources, i.e. defossilised fuels. This development leads to three possible energy sources or forms of energy for use in individual transport. The first possibility is charging with electricity generated from renewable sources, the second possibility is hydrogen generated from renewable sources or blue production path. The third possibility is the use of renewable fuels, also called e-fuels. These fuels are produced from atmospheric CO2 and renewable hydrogen. Possible processes for this are, for example, methanol or Fischer-Tropsch synthesis. The production of these fuels is very energy-intensive and large amounts of renewable electricity are needed.

By analyzing the dynamic distortion in all body closure openings in a complete vehicle, a better understanding of the body characteristics can be achieved compared to traditional static load cases such as static torsional body stiffness. This is particularly relevant for non-traditional vehicle layouts and electric vehicle architectures. The body response is measured with the so-called Multi Stethoscope (MSS) when driving a vehicle on a rough pavé road (cobble stone). The MSS is measuring the distortion in each opening in two diagonals. During the virtual development, the distortion is described by the relative displacement in diagonal direction in time domain using a modal transient analysis. The results are shown as Opening Distortion Fingerprint ODF and used as assessment criteria within Solidity and Perceived Quality. By applying the Principal Component Analysis (PCA) on the time history of the distortion, a Dominant Distortion Pattern (DDP) can be identified.

Computer modelling, virtual prototyping and simulation is widely used in the automotive industry to optimize the development process. While the use of CAE is widespread, on its own it lacks the ability to provide observable acoustics or tactile vibrations for decision makers to assess, and hence optimize the customer experience. Subjective assessment using Driver-in-Loop simulators to experience data has been shown to improve the quality of vehicles and reduce development time and uncertainty. Efficient development processes require a seamless interface from detailed CAE simulation to subjective evaluations suitable for high level decision makers. In the context of perceived vehicle vibration, the need for a bridge between complex CAE data and realistic subjective evaluation of tactile response is most compelling. A suite of VI-grade noise and vibration simulators have been developed to meet this challenge.

Previous studies have shown that dosing AdBlue into the exhaust system of diesel engines to reduce nitrogen oxides can lead to an increase in the number of particles (PN). In addition to the influencing factors of exhaust gas temperature, exhaust gas mass flow and dosing quantity, the dosed medium itself (AdBlue) is not considered as a possible influence due to its regulation in ISO standard 22241. However, as the standard specifies limit value ranges for the individual regulated properties and components for newly sold AdBlue, in reality there is still some margin in the composition. This paper investigates the particle number increase due to AdBlue dosing using several CPCs. The increase in PN is determined by measuring the number of particles after DPF and thus directly before dosing as well as tailpipe. Several AdBlue products from different sources and countries are measured and their composition is also analyzed with regard to the limit values regulated in the standard.

The phenomenon of automotive bumper impact conforms to the theory of classic physics. The basic variables of impact can be measured, recorded, and analyzed with “state-of-the-art” test equipment. The goal of this paper is to demonstrate the test techniques available to measure and analyze impact. The initial parameters of impact are mass, velocity, and geometry. The resulting variables of impact are force, acceleration, displacement, rebound velocity, and impact energy. These parameters and variables can be recorded, measured, and analyzed within a bumper test laboratory. The relationship between the initial conditions and resulting impact phenomenon follow the laws of classical Newtonian physics. This paper discusses the methodology for testing and measuring automotive bumper performance and demonstrates how modern testing methods can help evaluate relative bumper performance.

High repair cost and the subsequent increase in insurance cost in a highly competitive automobile market have forced every automobile original equipment manufacturer (OEM) to comply with the FMVSS and ECE-42 regulatory requirements of low-speed vehicle damageability. Although, the terminologies used are different, similar regulatory requirements also exist in Asia-pacific region. At the rear side, reducing the damage to expensive vehicle components in a low-speed pendulum impact or a low-speed barrier impact can attain a good rating for low-speed vehicle damageability. This paper focuses on a detailed study of various lightweight plastic rear beam designs and their effectiveness in reducing the damage to the vehicle during low-speed vehicle-to-vehicle collision or vehicle to barrier collision.

With the recent change to the Canadian bumper impact requirement (CMVSS 215) to match Title 49, part 581 of Code of Federal Regulation of the United States (CFR part 581) and/or ECE R42 there is a tendency to think that having capable energy absorbers is no longer beneficial. However, many benefits of thermoplastic energy absorbers are still relevant. For example, highly efficient energy absorbers allow vehicle package space to be minimized. This can help improve vehicle styling or reduce vehicle mass. Thermoplastic energy absorbers (EA) have a history of helping solve poor overlap conditions in both pendulum impacts and deformable barrier impacts. Because of the increased emphasis placed on avoiding high pendulum plane loads as defined in CFR part 581, good “catching” capability from an EA is highly advantageous.

Evaluation of the severity of low speed motor vehicle crashes has been the subject of significant research for more than 25 years. These crashes typically result in little if any damage to the vehicles involved and therefore the ability to determine the threshold of damage would be very useful in analysis of such cases. One such threshold, which has been used by accident reconstructionists, is the manufacturer’s published bumper rating in compliance with Federal Motor Vehicle Safety Standards (FMVSS) for vehicle bumpers. The rationale is that if there is any damage to the bumper system of the vehicle in question, the impact must have had a severity greater than the rated bumper speed. This paper examines the FMVSS bumper standards upon which the published bumper ratings are reportedly in compliance, historical low speed testing damage results, and engineering considerations of bumper damage in low speed impacts.

The dimensions of automobile-body seats receive consideration with regard to the features that are conducive to comfort. A diagram is presented upon which the dimensions treated are indicated, and a tabulation of seat dimensions of 12 representative cars is included. Comments are made upon the factors influencing seat dimensions, as well as recommendations regarding the different desirable dimensions. The considerations are inclusive of cushion height, depth and slope, leg-room and head-room, upholstery shape and softness of trimming, foot-rest and other control-element locations, factors influencing entrance and egress provisions, seat widths and advisable front and rear-compartment heights. The author recommends the standardization of a range of locations for the different control elements.

Motorcycle collisions by their very nature are difficult at best to analyze and/or reconstruct. Motorcycles come in as many different types, models and styles as do passenger vehicles and trucks. The inherent problems of load changes and articulation are enough to discourage anyone from reconstructing these type of collisions. This document is a result of efforts by members of the Washington State Patrol Traffic Investigation Division and members of the Washington State Patrol Academy. The purpose of the tests was to use the G-Analyst to determine the most appropriate value for both rear and front brake resistance during brake application and to make some comparisons of acceleration rates and deceleration rates.

Fatigue simulation is an essential part of the development of components and systems in the automotive and machinery industry. Weak points can be identified fast and reliable. A pure virtual optimization of the design can be performed without the need of prototypes. Only for the production release a final test is necessary. A lot of parameters influence the fatigue life as the local stress, material, surface roughness, temperature etc. Notches have the strongest impact on fatigue life since they cause an increase of the local stress. Also, the local fatigue strength is increased in notches because of a support effect from the neighboring areas. To account for this effect, several methods exist, each with their specific advantages and disadvantages. In this contribution an overview is given with brief descriptions for some common methods. The methods are compared both from a theoretical and practical point of view.

High cycle fatigue (HCF) S-N curves of steels are applied by OEMs for direct evaluation of the products' durability or as an input to their CAE for design purpose. It has been found that the existing models for S-N data resulting HCF test might have difficulties in properly depicting the entire spectrum of fatigue lives. To overcome these difficulties, a new equation has been developed based on the relationship between the behaviors of short and long fatigue lives. The new equation was applied to model S-N data resulting from recent HCF testing of several steels and was compared with the 3 existing popular models. The comparison in the preliminary validations indicated that the new equation has high potential for application in more accurate S-N data modeling and fatigue limit prediction.

The active sound generation systems (ASGS) for electric vehicles (EVs) play an important role in improving sound perception and transmission in the car, and can meet the needs of different user groups for driving and riding experiences. The active sound synthesis algorithm is the core part of ASGS. This paper uses an efficient variable-range fast linear interpolation method to design a frequency-shifted and pitch-modified sound synthesis algorithm. By obtaining the operating parameters of EVs, such as vehicle speed, motor speed, pedal opening, etc., the original sound signal is interpolated to varying degrees to change the frequency of the sound signal, and then the amplitude of the sound signal is determined according to different driving states. This simulates an effect similar to the sound of a traditional car engine. Then, a dynamic superposition strategy is proposed based on the Hann window function.

Noise reduction is generally accomplished by applying appropriate noise control treatments at strategic locations. Noise control treatments consisting of poroelastic materials in layers are extensively used in noise control products. Sound propagation through poroelastic materials is governed by macroscopic material and geometric properties. Thus, a knowledge of material properties is important to improve the acoustical performance of the resulting noise control products. Since the direct measurement of these properties is cumbersome, these have been usually estimated indirectly from easily measurable acoustic performance metrics such as normal incidence sound transmission and/or absorption coefficient, measured using readily available impedance tube. The existing inverse characterization approaches fulfilled the estimation by curve fitting measured and predicted acoustic models.

Systems-Theoretic Process Analysis (STPA) is being used as a hazard analysis technique within automotive, due in part to its systems engineering viewpoint making it suitable to automated driving feature analysis and with several new and emerging standards and guidelines suggesting its use as one option its familiarity is increasing. Approaches incorporating the human into the STPA Control Structure Diagram (CSD) have been proposed, such as Engineering for Humans: A New Extension to STPA [1]. Such approaches position the human as the top controller in the CSD hierarchy. While placing the human at the top of the CSD is suited to reasoning about supervisory human machine interactions, perhaps in an industrial control setting, we argue that a different approach is needed to address automotive shared control. In an automotive context the driver is integral to vehicle control.

The negative effects of long-term exposure to soot and particulate matter emissions from diesel exhaust on the human health have been widely acknowledged due to the harmful substances that exhaust gas contains. Regulators have established strict programs to determine the performance and reliability of emissions after-treatment systems and devices. Tests were conducted to evaluate the efficacy of three diesel particulate filter (DPF) cleaning methods: 1) thermal and pneumatic cleaning, 2) ultrasonic cleaning, and 3) aqueous cleaning methods. A novel non-destructive method to quantify soot and ash deposits in the filters was developed, validated and used to determine the effectiveness of the identified cleaning methods. Given the number of different cleaning methods available, testing against a set of standard parameters provided accurate comparative results.

Typical everyday driving scenarios involve acceleration ranges which are relevant to accident reconstruction. Understanding the motions and accelerations endured in common driving maneuvers can help quantify the accelerations of vehicles and occupants when reconstructing a collision. This paper evaluates various everyday driving conditions, such as traversing speed bumps and dips, and impacting parking blocks. The purpose of this paper is to quantify the accelerations experienced during everyday driving scenarios to provide a reference for impact severity analysis in the field of accident reconstruction.

In vehicle development, reducing noise is a major concern to ensure passenger comfort. As electric vehicles become more common and engine and vibration noises improve, the aerodynamic noise generated around the vehicle becomes relatively more noticeable. In particular, the fluctuating wind noise, which is affected by turbulence in the atmosphere, gusts of wind, and wake caused by the vehicle in front, can make passengers feel uncomfortable. However, the cause of the fluctuating wind noise has not been fully understood, and a solution has not yet been found. The reason for this is that fluctuating wind noise cannot be quantitatively evaluated using common noise evaluation methods such as FFT and STFT. In addition, previous studies have relied on road tests, which do not provide reproducible conditions due to changing atmospheric conditions. To address this issue, automobile manufacturers are developing devices to generate turbulence in wind tunnels.

As the mobility being developed becomes more complex and numerous, it is becoming difficult and inefficient to apply current vehicle-test-based development. To overcome this, research on combining test and simulation models has been actively conducted to perform objective and subjective evaluations more accurately and efficiently in the advance stage without a vehicle over the years. At first, test models for various systems such as tire, suspension and body were made compatible with simulation models by using various methodologies such as blocked forces, FBS decoupling, and Virtual Point Transformation (VPT). The second step was to objectively estimate road noise by using FBS coupling with system models and to deeply analyze transfer paths and system’s sensitivity. The results were verified by comparing with what was measured and analyzed on vehicle.