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Abstract Due to the presence of uncertain disturbances in the actual steering system, disturbances in the system may affect the handling stability of the vehicle. Therefore, this article proposes an integrated steering system control strategy with stronger anti-disturbance performance. When disturbances exist in the system, the proposed control strategy effectively reduces the attitude changes during the vehicle steering process. In the upper-level control strategy, a variable transmission ratio curve is designed to coordinate the high-speed handling stability and low-speed steering sensitivity of the vehicle. On this basis, a sideslip angle observer is proposed based on the extended state observation theory, which does not depend on an accurate system model, thus determining the intervention timing of the active front wheel steering system. In the lower-level control strategy, DR-PI/DR-PID controllers are designed for the integrated steering system.

Abstract To realize the dynamics concept “enjoy driving” of new-model cars, engine sound was based on the concept of “exhilarating.” To achieve “exhilarating,” we compared current models with competitor cars to understand the countermeasure sound characteristics. As a result, it was found that the rumble noise at low-RPM medium load needs to be reduced. To reduce rumble noise, the crankshaft system and power train stiffness were refined. As a result, we were able to achieve our goal of exhilarating engine sound. However, as the evaluation of sound after a vehicle is sold is generally left to the user, there are few studies that examine whether a car is more highly evaluated based on the sounds it creates. Therefore, this study was conducted to evaluate concept compatibility and loyalty in relation to exhilarating engine sound in the U.S. market for Generation Z, the target group for the new car.

The high-performance and motorsport vehicle sectors are pushing the performance frontiers of aerodynamically efficient vehicles. Well-balanced use of accurate and consistent numerical simulation tools in combination with wind tunnel experiments is crucial for cost-effective aerodynamic research and development processes. Therefore, this study assesses the simulation performance of four Reynolds-averaged Navier–Stokes (RANS) turbulence models in relation to experimental and high-fidelity delayed detached eddy simulation (DDES) data for the aerodynamic assessment of a high-performance variant of the DrivAer model (DrivAer hp-F). The influences of predominant wind tunnel conditions on the vehicle’s aerodynamic force coefficients and flow field are also investigated. Additionally, a novel CFD-based blockage correction method is introduced and applied to evaluate the accuracy of conventional blockage correction methods.

This research explores friction stir welding (FSW) to examine the mechanical characteristics and microstructure of thick plates manufactured from the Mg-8Al-0.5Zn alloy. Applying the FSW procedure to warm-form an Mg-8Al-0.5Zn alloy for the differential case covering the gears in the car’s automotive technology. Weld quality was significantly improved after using response surface methodology (RSM) to examine various welding parameters and find the best configurations. Improved grain refinement and phase distribution in the weld zone were found in the microstructural study of 11.5 mm thick magnesium alloy plates using RSM-optimized parameters. By dynamic recrystallization, the grain size was reduced to 16 μm, which is fifteen times smaller than the original material, thanks to the good results of single-pass FSW welding.

In regions with hot and humid climatic conditions, lightweight cotton textiles such as lawns, are famous for clothing and being explored for use in automobile interiors. Specifically, there’s an interest in these fabrics for car seat covers, interior roof linings, and door trims. Textiles must balance weight and durability for automotive applications to ensure passenger comfort while withstanding regular wear and tear. This study assesses cotton fabrics’ wear and mechanical performance with densities between 40 and 60 g/m2, produced using yarn counts of 70, 60, and 40 Ne. The objective was to determine the optimal fabric parameters for creating automotive spare parts that are both durable and comfortable. Two production strategies were contrasted: coarser yarn counts with fewer warp and weft threads per inch and finer yarn counts with a higher thread density.

Researchers have chosen to study natural fibers instead of synthetic fibers since low-cost and ecologically favorable materials are required. The present research concentrates on the mechanical characteristics of epoxy composites reinforced with bamboo and bagasse fibers. The hybrids were created using four different ratios of bamboo/bagasse fibers, then hand-laid up. The material characteristics of the generated composites, including tension, bending, impacts, and Shore D hardness measurements, were assessed. The scanning electron microscopy technique was used to study morphology. Three levels of bamboo and a core network of bamboo fibers in composites were assumed to generate superior qualities. The core layer of bamboo and an outer layer typically characterized by sugarcane composites have enhanced flexural strength and Shore D toughness because of the bamboo layer at the center.

This SAE Recommended Practice establishes uniform procedures for testing fuel cell and hybrid fuel cell electric vehicles, excluding low speed vehicles, designed primarily for operation on the public streets, roads and highways. The procedure addresses those vehicles under test using compressed hydrogen gas supplied by an off-board source or stored and supplied as a compressed gas onboard. This practice provides standard tests that will allow for determination of fuel consumption and range based on the US Federal Emission Test Procedures, using the Urban Dynamometer Driving Schedule (UDDS) and the Highway Fuel Economy Driving Schedule (HFEDS). Chassis dynamometer test procedures are specified in this document to eliminate the test-to-test variations inherent with track testing, and to adhere to standard industry practice for fuel consumption and range testing.

This SAE Information Report relates to a special class of automotive adaptive equipment which consists of modifications to the power steering system provided as original equipment on personally licensed vehicles. These modifications are generically called “modified effort steering” or “reduced effort power steering.” The purpose of the modification is to alter the amount of driver effort required to steer the vehicle. Retention of reliability, ease of use for physically disabled drivers and maintainability are of primary concern. As an Information Report, the numerical values for performance measurements presented in this report and in the test procedure in the appendices, while based upon the best knowledge available at the time, have not been validated.

Abstract Fully flexible valve actuation (FFVA) is a key enabling technology of internal engine combustion research and development. Two laboratory electro-hydraulic FFVA systems have been developed and implemented in R&D test cells. These FFVA systems were designed using repetitive control (RC), which is based on internal model principle (IMP), for constant engine speed operation. With the engine operating in a steady-state condition, the valve profile input is periodic. This can be accommodated by a repetitive controller, which provides the function of flexible control to step changes in valve lift, valve opening duration, and cam phase angle position. During engine speed transients, as the valve reference trajectory becomes aperiodic in the time domain, the controllers based on the linear time invariant (LTI) IMP, such as RC, are no longer applicable. Engine speed transient control is a desired function to engine research and other similar applications, such as motor control.

There is little reason to lose confidence in the overall trajectory of electric vehicles.

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