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Abstract In this work, a three-phase integrated onboard battery charger is investigated and implemented for electric vehicle (EV) applications. A three-switch add-on interface is introduced to connect with the inverter and the motor windings, such that a two-channel interleaved boost converter is formed for the battery charging. The detailed system analysis, design methodology, and control strategy are discussed. Moreover, a simulation study is carried out to validate the effectiveness of the proposed integrated charger. As verification, a 5 kW liquid-cooled prototype is built and tested. The proposed integrated charging system achieves a power factor of 0.99, and total harmonic distortion (THD) of 4.82% at 5 kW with an efficiency of 93.2%.

Abstract An efficient vehicle thermal management is essential to fulfil the requirements of fuel consumption and passenger comfort. Therefore, the design and dimensioning of the cooling system is under high scrutiny in new vehicle architectures. With increasing electrification, no longer just the load peaks define the design frame but also the dynamics of thermal loading and recovery. Consequently, electrified vehicle architectures such as plug-in hybrid fuel cell vehicles demand for alternative approaches regarding the design of cooling systems and the definition of the decisive criteria. This article presents a new methodology for designing the cooling system related to its demands in customer operation. The recorded fleet data is first filtered for high load driving, using the so-called thermal load integral (LI) as a filter criterion.

Abstract Automotive interior coatings for flexible and rigid substrates represent an important segment within automotive coating space. These coatings are used to protect plastic substrates from mechanical and chemical damage, in addition to providing colour and design aesthetics. These coatings are expected to resist aggressive chemicals, fluids, and stains while maintaining their long-term physical appearance and mechanical integrity. Designing such coatings, therefore, poses significant challenges to the formulators in effectively balancing these properties. Among many factors affecting coating properties, the cross-link density (XLD) and solubility parameter (δ) of coatings are the most predominant factors.

Abstract Maximum lifetime and minimum manufacturing cost for new products are the primary goals of companies for competitiveness. These two objectives are contradictory and the geometric dimensions of the products directly control them. In addition, the earlier design errors of new products are predicted, the easier and more inexpensive their rectification becomes. To achieve these objectives, we propose in this article a novel model that makes it possible to solve the problem of optimizing the lifespan and the manufacturing cost of new products during the phase of their design. The prediction of the life of the products is carried out by an energy damage method implemented on the finite element (FE) calculation by using the ABAQUS software. The manufacturing cost prediction is carried out by applying the ABC cost estimation analytical method. In addition, the optimization problem is solved by the method of genetic algorithms.

Abstract Tailored blanks offer great lightweighting opportunities for automotive industry and were applied on the front rails of a sedan in this research. To achieve the most efficient material usage, all the front rail parts were tailored into multiple sheets with the gauge of each sheet defined as a design variable for optimization. The equivalent static loads (ESL) method was adopted for linear optimization and the Insurance Institute for Highway Safety (IIHS) moderate overlap frontal crash as the nonlinear analysis load case. The torsion and bending stiffness of the sedan body in white (BIW) were set as design constraints. The occupant compartment intrusion in IIHS moderate overlap front crash was set as design objective to be minimized. The optimal thickness configuration for the tailored front rail designs was obtained through ESL optimization for multiple mass saving targets.

Abstract Advanced Driver Assistance Systems (ADAS) are playing a significant role in enhancing driver safety and occupant comfort in modern vehicles. The primary research focus in this domain includes the precise perception of the current state and the prediction of the future states of dynamic agents. To perform these tasks an intelligent agent capable of operating in the stochastic environment is implemented in the form of various ADAS features. A trajectory prediction problem can be defined using either a model-based or data-driven approach. The current article addresses the problem of trajectory prediction in the stochastic environment using a model-based approach with a quintic polynomial as a function approximator to ensure smooth acceleration trajectory for the left and right lane-change maneuvers. The task of trajectory prediction also considers the information about the vehicle dynamics, the concept of Receding Time Horizon (RTH), and the variable curvature model of the road.

Abstract Platform sharing is widely used for reducing time and cost of vehicle development. It has been believed that vehicles that employ the same platform show similar performances of noise and vibration. Recently, however, it is observed that two vehicles that share the same platform present a noticeable difference in road noise. The structural difference between the two vehicles is located only at the upperbody of a Body In White (BIW). In order to investigate the effects of the upperbody on the road noise, several analyses such as (1) input point stiffness, (2) noise transfer function (NTF), and (3) road noise are performed using finite element (FE) models of the vehicles. As a result, it is found that the upperbody affects the NTF of the trimmed body and the road noise, which explains the dissimilarity of the road noise for the two vehicles. A novel method based on equivalent radiated power (ERP) is proposed to assess the upperbody.

Abstract This article focuses on passenger cars whose car structure is separated from the chassis. The elastic properties of the car structure, often measured with static and dynamic stiffness parameters, have significant influence on driving dynamics (which includes handling and riding comfort). However, a design process based on empirically determined target values for those stiffness parameters does not guarantee adequate structural quality in terms of driving dynamics requirements. Vehicle vibration behavior, which is perceived as driving dynamics, has a frequency range up to approximately 20 Hz with acceleration amplitudes sufficiently large to be feelable. Previous research assumes that the vibration behavior of the car structure itself cannot be relevant for driving dynamic perception as the lower limit for its vibrations is given by the first-order bending and torsional modes, which are normally above 20 Hz.

Abstract As part of the development of an automated virtual design classification approach for nonlinear structural dynamics, alternative excitation functions are evaluated with respect to their overall performance and efficiency in feature-based response analysis. Robust design of nonlinear structures requires analysis of extensive parameter variations. Both the character of the stimulus and feature metrics used are central to the performance of a response classification approach. The main purpose of this study is to compare stimulus candidates with respect to their efficiency in response classification. A deterministic multilevel, multifrequency stepped-sine periodic test function is used as a baseline. Order-wise differences between generalized and linearized system frequency response functions are evaluated by a selected feature metric to allow categorization into primary, sub and super harmonic responses, as well as odd and even order response distortions.

Abstract This article presents a problem that originates from a control design case study for lateral control of automated automotive vehicles. A lane-keeping control algorithm was developed and tested in a simulation environment and was planned to be implemented in a test vehicle. First, tests showed significantly deteriorated and unstable performance results of the corresponding controller caused by sensor delays and actuator imperfections. After the diagnosis of the problem, an approach to mitigate these issues was undertaken by predicting the delayed sensor data utilizing a linear Kalman filter and an a priori predictor. The Kalman filter and a priori predictor design approach are based on a discrete time version of the lane-tracking model. The proposed measures are easy to be implemented on real-time hardware due to low computational effort. The approach is described using simulation results and verified with results from a test vehicle in real driving conditions.

Abstract Recently, permanent magnet (PM)-assisted reluctance (PMAREL) machines are gaining increasing attention for traction applications to reduce magnet consumption. In this article, a comprehensive design methodology is applied to design a PMAREL machine for an electric vehicle (EV) propulsion application. The design method includes both electromagnetic and mechanical analyses. A finite element analysis (FEA)-based differential evolution (DE) algorithm is adopted to find the best reluctance (REL) rotor geometry. The PM dimensions are calculated analytically, which allows a fast identification for the initial design. An FEA model for mechanical analysis is developed, and some remedial techniques are adopted to improve the mechanical stress. The design procedure starts with the selection of the stator split ratio. Then it continues with REL optimization and PM dimension determination.

Abstract Lubrication has been a major area of interest in engineering. Especially in vehicle transmissions, lubrication plays a very crucial role because gears and bearings are constantly subjected to heavy loads. Proper lubrication is essential for maintaining system performance and ensuring endurance life. Insufficient lubrication can lead to excessive wear, increased friction, and eventually, failures in the transmission components. However, excess lubrication can result in power losses due to the resistance offered by the excessive lubricant. Therefore, achieving effective lubrication using optimized lubrication system design is vital for ensuring the longevity and efficiency of the transmission system. Majorly, two types of lubrication methods are used in transmissions: splash lubrication and forced lubrication. This article focuses on forced lubrication, where the lubrication system actively delivers the required flow of lubricant to specific locations within the transmission.

Abstract Aircraft lift bag is the equipment used for the recovery of an aircraft and is considered as a lifting equipment. Boeing 737 is a domestic aircraft considered for designing this bag. The aircraft lift bag is made of composite material, and the most widely used materials are nylon and neoprene. A composite material is used to make the bag lightweight and easy to handle. For calculation of properties and the engineering constant of the respective composite materials, micromechanics approach is used, in which the method of Representative Volume Element (RVE) is taken into consideration. The loading and boundary conditions are the exact replica of the working conditions. The operation of this bag is completely pneumatic. The stresses induced in the bag are analyzed in finite element software and are compared with the calculated theoretical values. CATIA is used to model the bag, and ABAQUS is used for the finite element calculations.

Abstract In this study, an attempt is made to deduce the number of teeth in the driven sprocket of a Formula SAE (FSAE) car using Optimum Lap software based on track run simulation of the car, which comes out to be 51 teeth. The sprocket material was selected as Aluminum Alloy AL-7075 T6 because of its strength-to-weight ratio. In addition to it, the generative design strategy by Fusion-360 was utilized to automatically engender the slotted sprocket design on the ground of stress induced on it during operation. Furthermore, the design was verified virtually carrying out static structural and fatigue analysis under the worst-case scenario in CAE software. The overall weight reduction achieved was around 45%. Furthermore, the center-to-center distance between the sprockets and the number of chain links required were also calculated on the basis of space constraints and the wrap angle of the sprocket.

Abstract Electrification of vehicles can improve energy efficiency and reduce emissions in vehicle operations. Studies have focused on designing powertrains of several topologies, including serial, parallel, and power-split hybrid powertrains. In this study, a design and control co-optimization is demonstrated for a novel mixed-powertrain architecture. The component sizes of the mixed powertrain are optimized to minimize the fuel and component costs. Nested optimization is applied with a surrogate integrated operation and control model that evaluates powertrain performance in the inner loop. The surrogate model is trained to capture the powertrain performance under a near-optimal power management approach, namely, the equivalent consumption minimization strategy (ECMS). Using sequential quadratic programming, optimal results are obtained and verified using a high-fidelity powertrain model which is equipped with ECMS control.

Abstract The purpose of this research is to fabricate a multipurpose drone with different lightweight materials that are used for water irrigation as well as pesticide spraying in agricultural fields. Components are collected and the drone is fabricated based on the parameters required for payload, weight, and design calculations. After the completion of fabrication, the drone is tested using different masses of payload for better endurance. The drone arms are made of balsa wood and stands are fabricated with polyvinyl chloride (PVC) and carbon fiber. The obtained results proved that a full payload is able to fly for 7 min; at the same time if we reduce the payload to 50%, the endurance will be increased double the time. In this study, the same drone and pumping configuration is used to perform the water and pesticide irrigation over various areas on agricultural land, which is achieved by changing the tank quantity.

Abstract Aiming at solving the battery electric vehicle (BEV) problems of high energy consumption and low efficiency in heating at low temperature, this study takes the thermal management system of BEV as the research object and develops an integrated thermal management control system based on heat pump air-conditioning for BEV. First, the functional requirements and optimal operating temperature range of each BEV subsystem are defined. Second, on the basis of the thermodynamic cycle principle of the air-conditioning system and compared with the traditional positive temperature coefficient thermistor (PTC) heating mode, the high heating efficiency and low energy consumption advantages of the heat pump system in winter are highlighted.

Abstract The preeminent obligation of the automotive engineers, while designing a car, is to assure the driver’s well-being during any kind of impact by suppressing intrusions into the cockpit or minacious deceleration levels. Technologists and designers are advancing various modern active and passive safety systems to augment vehicle occupants’ safety. To mitigate the research and development expenditure in time and money, it is recommended to utilize computational crash simulations for the early evaluation of safety behavior under vehicle impact tests. Therefore, in this research study, an attempt is made to simulate crashworthiness and design the impact attenuator utilized in Formula SAE vehicles to absorb the kinetic energy of a car during a frontal collision. Closed-cell aluminum foam is selected as its material because of its less density than solid metals and ability to undergo large deformations at almost constant load.

Abstract Active systems, from active safety to energy management, play a crucial role in the development of new road vehicles. However, the increasing number of controllers creates an important issue regarding complexity and system integration. This article proposes a high-level controller managing the individual active systems—namely, Torque Vectoring (TV), Active Aerodynamics, Active Suspension, and Active Safety (Anti-lock Braking System [ABS], Traction Control, and Electronic Stability Program [ESP])—through a dynamic state variation. The high-level controller is implemented and validated in a simulation environment, with a series of tests, and evaluate the performance of the original design and the proposed high-level control. Then, a comparison of the Virtual Driver (VD) response and the Driver-in-the-Loop (DiL) behavior is performed to assess the limits between virtual simulation and real-driver response in a lap time condition.

Abstract Aiming at the problems of insufficient perception and adaptability of vehicle-mounted drilling rig control system to complex formation and unsatisfactory drilling efficiency, an adaptive drilling weight on bit (WOB) control system of the vehicle-mounted drilling rig is designed in this article. Based on the real-time monitoring of drilling parameters obtained by various sensors, the lithology of drilling formation is identified by particle swarm optimization-support vector machine (PSO-SVM), the corresponding high-efficiency WOB is matched according to the differences in rock properties of different formations, and the valve port size of electrohydraulic proportional overflow valve is controlled by fuzzy proportional-integral-derivative (PID) to adjust the feed force of the feed cylinder so that the WOB of the drilling rig can change adaptively with the formation, and the rock-breaking efficiency of the drilling rig can be improved.