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This paper has been withdrawn by the publisher because of non-attendance and not presenting at WCX 2024.

This paper has been withdrawn by the publisher because of non-attendance and not presenting at WCX 2024.

This paper has been withdrawn by the publisher because of non-attendance and not presenting at WCX 2024.

This paper has been withdrawn by the publisher because of non-attendance and not presenting at WCX 2024.

This paper has been withdrawn by the publisher because of non-attendance and not presenting at WCX 2024.

The objective of this study is to introduce and assess a computational tool designed to facilitate product development via sensory scores, which serve as a quantifiable representation of human sensory experiences. In the context of designing ride comfort performance, the specialized terminology—either technical or sensory—often served as a barrier to comprehension among the diverse set of specialists constituting the multidisciplinary team. In a previous study by the authors introduced a tool that incorporated a model of sensory performance, utilizing sensory scores as universally comprehensible metrics. However, the tool had yet to be appraised by a genuine cross-functional team. In this study, the tool underwent evaluation through a user-testing process involving twenty-five cross-functional team members engaged in the conceptual design phase at an automotive manufacturing company.

The Fly-By-Light Advanced Systems Hardware (FLASH) program is developing Fly-By-Light (FBL) and Power-By-Wire (PBW) technologies for military and commercial aircraft. The flight control system portion of FLASH focuses on the integration of fiber optic sensors, optic data buses, actuators (PBW, smart, rotary thin wing) and optic cable plant components for centralized and distributed flight control architectures. Laboratory demonstrations will show applicability to widebody commercial transport and military tactical aircraft. This paper summarizes the requirements, objectives, key technologies and demonstration configurations of each of three FLASH flight control system developments.

The mutual aerodynamic influence of road vehicles in close proximity is known to alter significantly the drag performance of the vehicles. This paper presents an extended analysis from a study of two open-access road-vehicle shapes (a DrivAer Notchback model and an AeroSUV Estateback model) in close lateral proximity with each other, or with other vehicle shapes. Wind-tunnel measurements were conducted for a yaw-angle range of ±10°, for lateral distances representing 75%, 100%, and 125% of a typical highway lane spacing, and for longitudinal distances up to 2 vehicle lengths forward and back. The results of a previous analysis of the data, which examined aerodynamic force measurements only, showed changes in drag coefficient of ±20% or more depending on the relative locations and wind conditions. In this paper, the force-coefficient results reexamined, and surface-pressure measurements are introduced to investigate the sources of the performance changes.

This is a follow-up report about the development of a cost-effective Palladium (Pd) zeolite-based (HC/NOx trap type) cold-start catalyst (CSC) [1] to meet the future more stringent Chinese vehicle tailpipe emission standard. The impacts of Pd /stabilizer combination within zeolite for the HC/NOx trapping efficiency, the high temperature aging and the durability of the CSCs will be demonstrated by the laboratory results within this paper. The feasibility of a Cu zeolite, a popular non-precious metal ion- zeolite CSC for vehicle applications with respect to cost saving options will be demonstrated. A more complete picture of the effects of PGM/stabilizer within the zeolite to the functions of a CSC will also be summarized in this paper. All results indicate clearly that without the PGM/stabilizer within the zeolite, it would be difficult for the zeolite-based HC/NOx trap type CSC catalyst to be practically used for a vehicle application.

With the implementation of BS6 Norms, there is an increased focus on reducing particulate matter emissions from gasoline Direct Injection (GDI) engines. GPFs are effective in capturing particulate matter (PM) and particulate number (PN) but their calibration is critical to ensure optimal performance and emissions compliance. This paper presents a study on the calibration of Gasoline Particulate Filters (GPF) to comply with Bharat Stage-6 (BS6) emissions norms. The focus is on thermal management, soot loading, ash loading, and the unique challenges faced in the Indian market. Thermal management strategies include active and passive methods to optimize GPF regeneration and prevent thermal degradation. Soot load detection involves engine-out simulation-based approach as well as delta-Pressure-based approach for accurate soot modelling. Impact of ash loading and its effects on filtration efficiency and pressure drop will also be discussed.

Bharat Stage VI emission norms were implemented in India in two stages: Stage I from April 1, 2020, and Stage II from April 1, 2023. For M & N category vehicles, the RDE test along with other applicable certification tests is mandatory for obtaining a BSVI compliance certificate during stages I and II. The RDE test is conducted on roads under real driving conditions, unlike the Type-I test, which uses a predefined cycle on the chassis dynamometer, during which the ambient temperature and other environmental conditions are controlled in a narrow range. During BSVI Stage I for the RDE test, there was no limit for any pollutant. Therefore, it is considered as the RDE monitoring stage, and from BS-VI Stage II, limits are enforced on a few pollutants (NOX and PN) as notified in notification GSR 226(E) dated March 27, 2023. Therefore, it is considered the RDE compliance stage.

The ever-tightening regulation norms across the world emphasize the magnitude of the air pollution problem. The decision to leapfrog from BS4 to BS6 – with further reduction in emission limits -showed India’s commitment to clean up its atmosphere. The overall cycle emissions were reduced significantly to meet BS6 targets [1]. However, the introduction of RDE norms in BS6.2 [1] demanded further reduction in emissions under real time operating conditions – start-stop, hard acceleration, idling, cold start – which was possible only through strategies that demanded a cost effective yet robust solutions. The first few seconds of the engine operation after start contribute significantly to the cycle gaseous emissions. This is because the thermal inertia of the catalytic converter restricts the rate at which temperature of the catalyst increases and achieves the desired “light-off” temperature.

This paper provides measurement and analysis on rotor in-plane mode induced squeal. Methodology is presented to simultaneously acquire both temporal and spatial squeal operational deflection shapes (ODS). Rotor accelerations both in the in-plane and out-of-plane directions were measured during squeal along with rotor's normal ODS using a laser vibrometer. Modal measurement and analysis of the rotor and pad in the in-plane and out-of-plane directions were conducted as installed in system condition. The test results indicating rotor modal coupling in the in-plane are provided, and out-of-plane directions, and conclusions on in-plane mode induced squeal are proposed. In addition, the countermeasure for squeal reduction is discussed.

This paper will present an overview of research relating to tire-related accident studies and case studies in evaluating specific accident situations where tire disablements were also encountered. This paper also presents a comprehensive examination of selected accidents following tire disablements. Tire disablements include blowouts, tread separations, punctures, airouts, etc. Methodology for studying vehicle performance during tread separation is presented as well as results of full-scale tests where tread separations were induced. In this manner, vehicle transient response during tire disablements is also discussed. This paper also addresses warning signs preceding tire disablements that often accompany tread separation, as well as the human response in these situations.

”Tire blow-out” is a fast loss of air pressure that fills a vehicle tire, effecting from a puncture or a fatigue of tire structure. Statistical data, published in the United States, showed that “tire blow-out” caused more than 300,000 road accidents in the period of 1992–96 [1, 3]. Over 2000 people died in those accidents and many more were injured [1, 3]. The data and successful attempts of simulation presented in the work [1], prompted the author to try modeling and simulating this case of vehicle motion. The main emphasis in the hereto presented tests was put on qualitative assessment of vehicle behavior after a “tire blow-out”. The results presented in the work [1] show that the smallest motion disturbance of a vehicle takes place when the driver does not react (by turning the steering wheel or pressing the brake pedal). So, an assumption was made that the driver keeps a zero value of the steering wheel turning angle and pressure on the brake pedal.

For the past approximately 20 years, the Serial Peripheral Interface (SPI) has been the established standard for serial communication between a host or central microprocessor and peripheral devices. This standard has been used extensively in control modules covering the entire spectrum of automotive applications, as well as non-automotive applications. As the complexity of engine control modules grows, with the number of vehicle actuators being controlled and monitored increasing, the number of loads the central microprocessor has to manage is growing accordingly. These loads are typically controlled using discrete and pulse-width modulated (PWM) outputs from the microcontroller when real-time operation is essential or via SPI when real-time response is not critical. The increase of already high pin-count on microcontrollers, the associated routing effort and demand for connected power stages is a concern of cost and reliability for future ECU designs.

In the brake system, unevenly distributed disc-pad contact pressure not only leads to a falling-off in braking feeling due to uneven wear of brake pads, but also a main cause of system instability which leads to squeal noise. For this reason there have been several attempts to measure contact pressure distribution. However, only static pressure distribution has been measured in order to estimate the actual pressure distribution. In this study a new test method is designed to quantitatively measure dynamic contact pressure distribution between disc and pad in vehicle testing. The characteristics of dynamic contact pressure distribution are analyzed for various driving conditions and pad shape. Based on those results, CAE model was updated and found to be better in detecting propensity of brake squeal.

This paper documents the vehicle response of a tractor-semitrailer following a sudden air loss (Blowout) in a steer axle tire while traveling at highway speeds. The study seeks to compare full-scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models. Full-scale testing of a tractor-semitrailer experiencing a sudden failure of a steer axle tire was conducted. Vehicle handling parameters were recorded by on-board computers leading up to and immediately following the sudden air loss. Inertial parameters (roll, yaw, pitch, and accelerations) were measured and recorded for the tractor and semitrailer, along with lateral and longitudinal speeds. Steering wheel angle was also recorded. These data are presented and also compared to the results of computer simulation models. The first simulation model, SImulation MOdel Non-linear (SIMON), is a vehicle dynamic simulation model within the Human Vehicle Environment (HVE) software environment.

Brake squeal is a phenomenon of self-induced vibration of the brake components during braking. There are many kinds of brake squeal cases whose mechanisms require acting on a various number of potential root causes. Brake squeal phenomena can be generally separated into 2 main mode types related to the direction of disc vibration involved: in-plane mode and out-of-plane mode. For out-of-plane mode, a number of existing countermeasures can be potentially applied after characterization of the squeal occurrence condition by direct experiment or simulation analysis[1,2,3,4]. However, as there are many possible mechanisms and root causes for the in-plane modes[5,6,7,8,9,10,11,12,13], it is generally necessary to perform a detailed analysis of the vibration mechanism before implementing a countermeasure.

This paper examines the onset of brake noise and the mechanisms involved during the initial stages of noise occurrence. The emphasis is directed towards disc mode coupling and improvements are suggested to inhibit the coupling of the in-plane and out-of-plane modes with similar frequencies. To better understand the mechanisms, modal analysis of the system is carried out in a static condition but with varying pressure loads. In addition the operational deflection shape (ODS) was recorded under normal braking conditions using tri axial accelerometers attached on a disc. It was identified by a 3D scanning technique during squeal braking. Through a parametric study and using complex eigenvalue analysis the disc mode shapes were reproduced and correlated to the system results. The proposals to reduce mode coupling were successfully evaluated on a brake dynamometer and the results were confirmed with vehicle testing.