bluuebunny/crossref_metadata_2025 huggingface dataset:
The Important Role of GD&T in Mechanical Drawing, Design and Manufacturing for Students of Engineering Institutes
Authors: Ali Amr S.H.R. , Ali Akram M. S. , Amin Youssef W.R. , Ali Salah H. R.
Published: April 2024

Mechanical drawing plays an important role in managing, designing and implementing engineering projects, especially in the field of the automotive industry. The need for accuracy in element design and manufacturing is greater now than ever before in engineering industries. In order to increase accuracy, the part design and function must be clearly communicated between the design engineer and the manufacturing technicians, especially in automotive industry and feeder industries projects. Geometric Dimensions and Tolerances (GD&T) system of elements determines the quality, importance and price of the designed product. The standard used in the United States to define GD&T methodology is ASME Y14.5-2009 while the standard used in Europe is ISO 1101-2017. This article discussed the importance of using GD&T system including the types of geometrical features, limitations and accuracy, datum references frame and feature control frame to handle these symbols seamlessly. Moreover, the paper included a proposal to draw and design a drive shaft as a mechanical element to become a prototype when manufactured, with the aim of distributing it to achieve the highest possible quality. The performance evaluation was verified by distributing closed-ended questionnaires with a Likert scale of five answer choices. The sample size of students who provided answers was 33 students from the mechatronics engineering program. The results showed that more than 86% of mechanical drawing students showed great interest in the GD&T system lecture on the proposed drawing-sheet. While more than 83% were very satisfied with the inclusion of the GD&T system in the proposed mechanical drawing-sheet. In addition, the drawing and design took into account that the project operations are carried out with the least amount of waste of raw materials and reduce project risk. This is for the purpose of raising the educational and skill level of students in engineering colleges and higher institutes and technicians in automobile companies and their feeding industries.
Approaches for Developing and Evaluating Emerging Partial Driving Automation System HMIs
Authors: Glaser Yi G. , Kiefer Raymond , Glaser Daniel , Landry Steven , Owen Susan , Llaneras Robert , LeBlanc David , Leslie Andrew , Flannagan Carol
Published: April 2024

Level 2 (L2) partial driving automation systems are rapidly emerging in the marketplace. L2 systems provide sustained automatic longitudinal and lateral vehicle motion control, reducing the need for drivers to continuously brake, accelerate and steer. Drivers, however, remain critically responsible for safely detecting and responding to objects and events. This paper summarizes variations of L2 systems (hands-on and/or hands-free) and considers human drivers’ roles when using L2 systems and for designing Human-Machine Interfaces (HMIs), including Driver Monitoring Systems (DMSs). In addition, approaches for examining potential unintended consequences of L2 usage and evaluating L2 HMIs, including field safety effect examination, are reviewed. The aim of this paper is to guide L2 system HMI development and L2 system evaluations, especially in the field, to support safe L2 deployment, promote L2 system improvements, and ensure well-informed L2 policy decision-making.
Research on Bottom Collision of Battery Pack Based on the First Force Point
Authors: Yan Pengfei , Wang Fang , Ma Tianyi , Gao Yan , Han Ce
Published: April 2024

The rapid advancement of new energy vehicle technology has led to the widespread placement of battery packs at the bottom of vehicles. However, there is a lack of corresponding regulations and standards to guide aspects related to vehicle bottom safety. This lack of guidance obscures the relative importance of various parameters impacting the structural safety of battery packs under dynamic impact conditions. Consequently, research on battery pack bottom collisions holds practical significance and offers valuable reference material. This study proposed a method based on the first collision point to examine the impact of bottom collisions on the mechanical safety performance of battery pack bottoms. A finite element model of the battery pack was established to investigate the effects of different impact types. During the collision event, the first collision point on the battery pack absorbed the most energy, resulting in the most severe damage and the formation of a distinct dent at the first collision point. The results indicated that bottom collisions exert a substantial impact on the structural safety of battery packs, with stress concentration primarily occurring near the impact point. The analysis of the first collision point emerged as a critical aspect of the bottom collision process, offering insights into the safety performance of battery packs under bottom impact and revealing the damage mechanisms that transpire during such collisions. Additionally, This study offered essential data support for design, verification testing, and optimization of battery packs.
The Hybrid Friction Surfacing Deposition Assisted Arc Welding (FsaAW) Approach for Dissimilar Steel/Al Joining of Automobile Structure
Authors: Chudasama Gautam , Kalyankar Vivek , Chauhan Shiv
Published: April 2024

A multi-material design strategy of steel and aluminium alloy is a key solution in response to stringent emission requirements and to offset the additional weight of batteries in electric vehicles. However, dissimilar Al/steel welding is mainly challenging due to the formation of brittle and hard intermetallic compounds (IMC). In order to resolve the issue of IMC formation, the present study proposed an alternative manufacturing method consisting of friction surfacing deposition and arc welding. The proposed method involves two steps for dissimilar welding: step 1, friction surfacing deposition of aluminium alloy on the steel surface and step 2, arc welding of friction surfacing deposited steel and aluminium alloy. Auxiliary friction surfacing deposition acts as a preliminary bonding and avoids the direct contact between steel and aluminium alloy during arc welding, which eludes the IMC formation at the interface. 3.15 mm thick E46 steel and 3 mm AA6061-T6 were selected as base metals to investigate the feasibility of the proposed method. The welded joints were characterized by microstructure, microhardness, and lap-shear tests. Compared to conventional arc welding, the proposed method provides better mechanical performance. Additionally, the proposed method can also be applicable to other mutually insoluble dissimilar combinations.
Automatic Optimization Method for FSAE Racing Car Aerodynamic Kit Based on the Integration of CAD and CAE
Authors: Chen Yanjun
Published: April 2024

In the process of designing the aerodynamic kit for Formula SAE racing cars, there is a lot of repetitive work and low efficiency in optimizing parameters such as wing angle of attack and chord length. Moreover, the optimization of these parameters in past designs heavily relied on design experience and it's difficult to achieve the optimal solution through theoretical calculations. By establishing a parametric model in CAD software and integrating it with CFD software, we can automatically modify model parameters, run a large number of simulations, and analyze the simulation results using statistical methods. After multiple iterations, we achieve fully automatic parameter optimization and obtain higher negative lift. At the same time, the simulation process is optimized, and simulations are run based on GPUs, resulting in a significant increase in simulation speed compared to the original. The results show that automated optimization saves a lot of manpower costs, and compared to manual optimization, the negative lift coefficient of the optimized components has increased by around 10%.
Evolution of Light-Duty Gasoline Compression Ignition (LD-GCI) for High Efficiency and US Tier3- Bin30 Emissions
Authors: Sellnau Mark , Whitney Christopher , Shah Ashish , Sari Rafael , Klemm William , Cleary David
Published: April 2024

It is widely recognized that internal combustion engines (ICE) are needed for transport worldwide for years to come, however, demands on ICE fuel efficiency, emissions, cost, and performance are extremely challenging. Gasoline compression ignition (GCI) is one approach to achieve demanding efficiency and emissions targets. At Aramco Research Center-Detroit, an advanced, multi-cylinder GCI engine was designed and built using the latest combustion system, engine controls, and lean aftertreatment. The combustion system uses Aramco’s PPCI-diffusion process for ultra-low NOx and smoke. A P2 48V mild hybrid system was integrated on the engine for braking energy recovery and improved cold starts. For robust low-load operation, a 2-step valvetrain system was used for exhaust rebreathing.

Test data showed that part-load fuel consumption was reduced 7 to 10 percent relative to a competitive 2.0L European diesel engine. The GCI engine produced “near-zero” tailpipe emissions of NOx, smoke, HC, and CO at most warm operating conditions. At 1500rpm, the engine was capable of over 25bar BMEP, demonstrating excellent low-speed torque characteristics of the engine.

Cold transient tests were conducted on the US FTP75 drive cycle using a “virtual vehicle” test methodology. A real engine and aftertreatment system with controller were tested in combination with vehicle and transmission models. Measured fuel economy (mpg) was 61 percent higher than the baseline spark-ignited turbocharged engine in a large SUV vehicle. Hydrocarbon, carbon monoxide, and NOx and PM emissions were below the stringent US 2026 Tier3- Bin30 regulations. An electrically heated SCR catalyst was needed to meet NOx tailpipe targets.

In addition to room temperature cold starts, cold startability tests were conducted in a cold chamber down to -30 degrees C. Electric intake air heating combined with exhaust rebreathing provided robust cold starts without spark assistance.

When operated on commercial E10 gasoline, simulated life-cycle CO2 emissions were reduced about 31 percent relative to the baseline. When operated on low carbon eGasoline, CO2 emissions were reduced by an estimated 80 percent, which is competitive with various new energy vehicles (NEV) including battery electric vehicles. Overall, this work shows that GCI technology has evolved as an efficient, clean, and robust powertrain for future transport.
Downsizing a Heavy-Duty Natural Gas Engine by Scaling the Air Handling System and Leveraging Phenomenological Combustion Model
Authors: Balazadeh Navid , Munshi Sandeep , Shahbakhti Mahdi , McTaggart-Cowan Gordon
Published: April 2024

A potential route to reduce CO2 emissions from heavy-duty trucks is to combine low-carbon fuels and a hybrid-electric powertrain to maximize overall efficiency. A hybrid electric powertrain can reduce the peak power required from the internal combustion engine, leading to opportunities to reduce the engine size but still meet vehicle performance requirements. Although engine downsizing in the light-duty sector can offer significant fuel economy savings mainly due to increased part-load efficiency, its benefits and downsides in heavy-duty engines are less clear. As there has been limited published research in this area to date, there is a lack of a standardized engine downsizing procedure. This paper uses an experimentally validated one-dimensional phenomenological combustion model in a commercial engine simulation software GT-SUITE™ alongside turbocharger scaling methods to develop downsized engines from a baseline 6cyl (2.1 L/cyl, 26 kW/L) pilot-ignition, direct-injection natural gas engine. Since there is a reduced power demand from the engine in the hybrid powertrain over transient drive cycles, this study compares two methodologies to achieve a 230 kW engine: a reduction in number of cylinders at fixed displacement (4cyl- 2.1 L/cyl) and a reduction in cylinder displacement volume but retaining six cylinders (6cyl-1.4 L/cyl). The power for the downsized engine is reduced compared to the baseline engine since a future hybrid powertrain will not need as much power as a non-hybrid. By retaining similar total displacement and equivalent power rating, the impacts of engine size reduction can be distinguished from the scaling of the turbocharging and air handling system. The engines are evaluated over a series of steady-state and transient cycles based on a reduced load duty cycle for an engine in a hybridized vehicle. The results indicated that, as expected, downsized engines demonstrate increased peak cylinder pressure, exhaust gas temperature, boost pressure, and turbocharger speed compared to the baseline engine when all engines undergo the same reduced load duty cycle. Distinctly, the 6 cyl-1.4 L/cyl variant showed increased heat losses due to the higher surface area to volume ratio in the combustion chamber, while the 4 cyl-2.1 L/cyl variant had higher exhaust enthalpy losses. Both downsized engines showed lower friction losses than the baseline engine. Due to these offsetting effects, neither of the downsized engines showed a significant improvement in brake specific fuel consumption (BSFC). The change in mass due to the smaller engine offers only a minor improvement in payload capacity compared to the reduction in the maximum torque.
Comparison of the Predictive Capabilities of Chemical Kinetic Models for Hydrogen Combustion Applications
Authors: Ribnishki Aleksandar , Charles Cameron , Esposito Stefania , Akehurst Sam , Yuan Hao
Published: April 2024

Recent legislation banning the sale of new petrol and diesel vehicles in Europe from 2035 has shifted the focus of internal combustion engine research towards alternative fuels with net zero tailpipe emissions such as hydrogen. Research regarding hydrogen as a fuel is particularly pertinent to the so-called ‘hard-to-electrify’ propulsion applications, requiring a combination of large range, fast refuelling times or high-load duty cycles. The virtual design, development, and optimisation of hydrogen internal combustion engines has resulted in the necessity for accurate predictive modelling of the hydrogen combustion and autoignition processes. Typically, the models for these processes rely respectively on laminar flame speed datasets to calculate the rate of fuel burn as well as ignition delay time datasets to estimate autoignition timing. These datasets are generated using chemical kinetic mechanisms available in the literature. However, these mechanisms have typically been developed with a focus on hydrocarbon oxidation – e.g., syngas, natural gas, biofuels, diesel, and gasoline - and their validation datasets feature a very limited number of hydrogen-specific targets. Therefore, this study explores the predictive capability of six commonly used chemical kinetic mechanisms over a large dataset consisting of hydrogen-specific ignition delay time and laminar flame speed targets compiled using data available in the literature. Additionally, a sensitivity analysis was conducted to identify reactions that strongly affect the ignition delay time of hydrogen-air mixtures in the intermediate-temperature regime, where large ignition delay time deviations are observed compared to experimental results. The sensitivity analysis was followed by an exploratory study in ad-hoc mechanism adjustment.
Numerical Simulation of Ammonia-Hydrogen Engine Using Low-Pressure Direct Injection (LP-DI)
Authors: Xu Xiaoting , Wang Wei , Qi Yunliang , Wang Zhi , Min Haijiao , Li Fangwei , Yin Yong , Li Zhi
Published: April 2024

Ammonia (NH3), a zero-carbon fuel, has great potential for internal combustion engine development. However, its high ignition energy, low laminar burning velocity, narrow range of flammability limits, and high latent heat of vaporization are not conducive for engine application. This paper numerically investigates the feasibility of utilizing ammonia in a heavy-duty diesel engine, specifically through low-pressure direct injection (LP-DI) of hydrogen to ignite ammonia combustion. Due to the lack of a well-corresponding mechanism for the operating conditions of ammonia-hydrogen engines, this study serves only as a trend-oriented prediction. The paper compares the engine's combustion and emission performance by optimizing four critical parameters: excess air ratio, hydrogen energy ratio, ignition timing, and hydrogen injection timing. The results reveal that excessively high hydrogen energy ratios lead to an advanced combustion phase, reducing indicated thermal efficiency. Additionally, the injection of hydrogen during the intake stroke causes a decrease of ammonia during the intake process, while delaying the injection timing during the compression stroke results in uneven air-fuel mixture distribution, both contributing to a decline in indicated thermal efficiency. Under specific operating conditions of an excess air ratio of 1.0, 20% hydrogen energy ratio, -14°CA ATDC spark ignition timing, and -180°CA ATDC hydrogen injection timing, the engine achieved a maximum indicated thermal efficiency of 47.8%.
Light Duty Engine Performance Characteristics with Dimethyl Ether and Propane
Authors: De Ojeda William , Wu Simon (Haibao) , Ankobea-Ansah King , Hassan Hafiz Ahmad , Hall Carrie
Published: April 2024

The paper explores the performance characteristics of a compression ignition HYUNDAI 2.2L engine operating with Dimethyl Ether (DME). Test are carried out at three operating conditions that weigh heavily in the FTP75 certification cycle (1000rpm-12Nm, 1500rpm-50Nm, 2000rpm-100Nm). The engine features a high-pressure common rail fuel injection system designed to operate with liquified gases. The main component of the fuel system is a high-pressure pump that incorporates an electronic inlet metering valve commanded on a crank-angle base to control the rail pressure. The pump, which requires no pressure regulator, provides the flow needed to the injectors without flow returning to the inlet. This novel fueling system is leveraged in tests that are conducted to examine the impact of EGR, combustion phasing, injection pressure on efficiency and emissions. In addition, the impact of introducing 15% Propane by mass is examined. During the tests, the engine ECU is aided by an Engine Controller High Speed Oversight unit (ECHO) to provide combustion phasing control, improved cylinder-to-cylinder uniformity, and an effective optimization over the testing effort. The use of DME and Propane allowed for peak thermal efficiency of nearly 43%. These fuels enable significant carbon index (CI) reductions over the baseline Diesel fuel, with indications that 50% reduction in CO2 over the Diesel engine are possible.
Effective Utilization of Pt Catalyst in Three-Way Catalytic System by Employing Calcined Ceria with Alumina
Authors: Morita Itaru , Tanaka Hiroki , Saeki Shohei , Isayama Akihiro , Iwashina Katsuya , Nagao Yuki , Endo Yoshinori , Wakabayashi Takashi , Haneda Masaaki
Published: April 2024

To satisfy the stringent regulations for exhaust gas emissions from gasoline-powered vehicles, large amounts of Rh and Pd have often been employed in three-way catalysts (TWCs) as the main active components. On the other hand, Pt-based TWCs are not often used in gasoline vehicles because Pt is readily sintered by its exhaust gases at approximately 1000 °C [1, 2]. In general, Pt-based TWCs must be located away from large thermal loads to maintain the active sites for gas purification. Based on this background, we previously reported that employing a small amount of CeO2 calcined at 1000 °C (cal-CeO2) in Pt-based TWCs was one of the most effective approaches for improving the catalytic activity without increasing the amount of Rh and Pd [3]. The effect of cal-CeO2 was attributed to the higher redox performance and Pt dispersion derived from the strong interactions between Ce and Pt. Therefore, the resulting Pt-based TWCs exhibited high catalytic performance, despite the low specific surface area (SSA) of cal-CeO2 due to high temperature calcination. In this study, we demonstrated that the low SSA of cal-CeO2 can be easily improved by adding Al2O3. The SSA of Al2O3-modified CeO2 calcined at 1000 °C (Al2O3-CeO2) was 45% higher than that of cal-CeO2 owing to the inhibition of CeO2 sintering by Al2O3. In addition, the interactions with Pt were significantly improved, leading to higher redox performance and Pt dispersion compared to the corresponding Pt catalyst supported on cal-CeO2. To determine the effects on the catalytic performance, vehicle evaluations were performed after aging treatment by gasoline-powered engine. Al2O3-CeO2 was employed in a Rh/Pt double-layered TWC placed at the rear bed in a close-coupled system. The results of the FTP mode test cycles on a dynamometer indicate that the addition of Al2O3-CeO2 to Rh/Pt double-layered TWCs is clearly more effective for suppressing exhaust gas emissions than the addition of cal-CeO2.
On Road vs. Off Road Low Load Cycle Comparison
Authors: Wine Jonathan , Ahmad Zar Nigar , McCarthy, Jr. James , Prikhodko Vitaly , Pihl Josh , Tate Ivan , Bradley Ryan , Howell Thomas
Published: April 2024

Reducing criteria pollutants while reducing greenhouse gases is an active area of research for commercial on-road vehicles as well as for off-road machines. The heavy duty on-road sector has moved to reducing NOx by 82.5% compared to 2010 regulations while increasing the engine useful life from 435,000 to 650,000 miles by 2027 in the United States (US). An additional certification cycle, the Low Load Cycle (LLC), has been added focusing on part load operation having tight NOx emissions levels. In addition to NOx, the total CO2 emissions from the vehicle will also be reduced for various model years. The off-road market is following with a 90% NOx reduction target compared to Tier 4 Final for 130-560 kW engines along with greenhouse gas targets that are still being established. The off-road market will also need to certify with a Low Load Application Cycle (LLAC), a version of which was proposed for evaluation in 2021. Since the LLAC has not been finalized, this study is being conducted to compare and contrast the LLC for on-road with the LLAC for off-road as there might be some shared learnings. A US off-road production 2023 Fiat Powertrain 13L engine and aftertreatment system was chosen for this work. This engine is used in production for both off-road and on-road products, so it is a good choice for this study. The associated off-road aftertreatment system was aged for more relevant comparisons. The engine calibration was not altered for either of the low load cycles. This study shows that the cycles are quite different in nature as the market needs are different. The LLC includes a large fraction of operation at idle and lower speeds, representing products that use the engine primarily for motive power, where lower vehicle speed means a lower engine speed and load. The LLAC has more time and load spent at high speeds and slightly higher loads. The off-road products represented by this cycle often use the engine to drive auxiliary equipment which means higher parasitic loads and hand/fixed throttle. The comparison will include the use profiles, tailpipe NOx and greenhouse gas emissions (CO2, N2O).
Proactive Battery Energy Management Using Navigation Information
Authors: Rostiti Cristian
Published: April 2024

In this paper, a control strategy for state of charge (SOC) allocation using navigation data for Hybrid Electric Vehicle (HEV) propulsion systems is proposed. This algorithm dynamically defines and adjusts a SOC target as a function of distance travelled on-line, thereby enabling proactive management of the energy store in the battery. The proposed approach incorporates variances in road resistance and adheres to geolocation constraints, including ultra-low emission zones (uLEZ). The anticipated advantages are particularly pronounced during scenarios involving extensive medium-to-long journeys characterized by abrupt topological changes or the necessity for exclusive electric vehicle (EV) mode operation. This novel solution stands to significantly enhance both drivability and fuel economy outcomes.
Optimal Control Co-Design of a Parallel Electric-Hydraulic Hybrid Vehicle
Authors: Taaghi Amirhossein , Yoon Yongsoon
Published: April 2024

This paper presents an optimal control co-design framework of a parallel electric-hydraulic hybrid powertrain specifically tailored for heavy-duty vehicles. A pure electric powertrain, comprising a rechargeable lithium-ion battery, a highly efficient electric motor, and a single or double-speed gearbox, has garnered significant attention in the automotive sector due to the increasing demand for clean and efficient mobility. However, the state-of-the-art has demonstrated limited capabilities and has struggled to meet the design requirements of heavy-duty vehicles with high power demands, such as a class 8 semi-trailer truck. This is especially evident in terms of a driving range on one battery charge, battery charging time, and load-carrying capacity. These challenges primarily stem from the low power density of lithium-ion batteries and the low energy conversion efficiency of electric motors at low speeds. To address these issues, a recent development is the electric-hydraulic hybrid powertrain. This system includes a hydro-pneumatic accumulator (i.e. a hydraulic energy storage system) and a hydraulic pump/motor (i.e. a hydraulic-mechanical energy conversion system) in addition to all the components of the electric powertrain. The high-level energy control methods of this hybrid powertrain have been extensively studied. In this work, an optimal control co-design framework involving hardware sizing and high-level energy control for a parallel electric-hydraulic hybrid powertrain is addressed. The objective is to maximize overall energy efficiency using a bi-level optimization method. The outer loop seeks optimal sizes for two energy storage systems: the rechargeable lithium-ion battery capacity and the hydro-pneumatic accumulator volume, determining the maximum electric and hydraulic storable energies. Meanwhile, the inner loop aims for optimal energy control with a set of energy storage system sizes using dynamic programming. Numerical studies demonstrate considerable benefits of the proposed control co-design method by applying it to real-world heavy-duty driving cycles. These benefits include reduced electric energy consumption of the lithium-ion battery, potentially allowing for a smaller battery size. Consequently, this increases load-carrying capacity and subjects the rechargeable battery to milder electric stress, thus extending the lifespan. These improvements are achieved through an aggressive use of hydraulic components during regenerative braking and high torque conditions at low vehicle speeds.
Consideration of Belt Losses of a Belt-Starter Generator(BSG)/Front-End Accessory Drive Electric Machine in an Optimal Torque Control Problem of a Hybrid Supervisory Controller
Authors: Senft Stefan , Patel Nadirsh
Published: April 2024

As electrification of powertrains is progressing, diversification of hybrid powertrains increases. This generally imposes the challenge for a supervisory controller of how to optimally control the torque of the electric machine(s). Architectures, which have at least one belt driven electric machine, are an essential part of the portfolio. This paper describes a strategy on how to include the losses of the belt device in the determination of optimal electric machine torque command.

It first depicts a physics-based method for controlling optimal electric machine torque command for systems without a belt connected electric machine. This method considers the constraints of the electric machine(s) as well as the power limitations from the electric devices, which supply power to the motors. The solution presented in this paper, utilizes a control method, which uses a quadratic fit of electric machine losses and a mathematical formulation for an analytic solution of the problem, which is then enhanced to consider the losses of the belt connection as well. The software concept of the supervisory control utilizes remapping and reformulation of the interfaced communication signals to the motor control unit, which are executed in real-time on the supervisory control. The benefits of this method are increased efficiency, a more robust consideration of constraints and significant computational efficiency gained by avoiding additional optimization loops.
Performance Evaluation of an Eco-Driving Controller for Fuel Cell Electric Trucks in Real-World Driving Conditions
Authors: Spano Matteo , Shiledar Ankur , Gupta Shobhit , Villani Manfredi , Misul Daniela , Canova Marcello , Rizzoni Giorgio
Published: April 2024

Range anxiety in current battery electric vehicles is a challenging problem, especially for commercial vehicles with heavy payloads. Therefore, the development of electrified propulsion systems with multiple power sources, such as fuel cells, is an active area of research. Optimal speed planning and energy management, referred to as eco-driving, can substantially reduce the energy consumption of commercial vehicles, regardless of the powertrain architecture. Eco-driving controllers can leverage look-ahead route information such as road grade, speed limits, and signalized intersections to perform velocity profile smoothing, resulting in reduced energy consumption. This study presents a comprehensive analysis of the performance of an eco-driving controller for fuel cell electric trucks in a real-world scenario, considering a route from a distribution center to the associated supermarket. The eco-driving strategy hereby proposed is based on an Approximate Dynamic Programming framework that uses a long-term route optimization to then solve a short-term model predictive control problem. Model-in-the-Loop simulations are performed using a high-fidelity plant model of a fuel cell electric truck. The objective of this work is to assess the performance of the eco-driving controller by conducting large-scale simulations that consider variability in the traffic conditions. The results obtained by the proposed eco-driving controller are finally compared against an ideal benchmark strategy referred to as wait-and-see controller, to quantify the energy benefits using the Probability Density Function. The estimated hydrogen consumption slightly increases by approximately 1.3% when comparing the proposed eco-driving controller with the wait-and-see benchmark. On the other hand, travel time is minimally impacted with a mean difference of few seconds, however the changes in formulation allow the proposed controller to be implemented in real-world and to obtain realistic results. The obtained results confirm the quality of the proposed eco-driving controller, robust to sudden changes in exogenous inputs.
Research on Motor Control and Application in Dual Motor Hybrid System
Authors: Jing Junchao , Huang Weishan , Liu Yiqiang , Dai Zhengxing , Zhang Junzhi
Published: April 2024

This paper analyzes the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Current control includes current vector control, MTPA control, flux weakening control, PI current control and SVPWM control. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode, battery heating mode and boost mode. The boost strategy of the hybrid system is based on boost mode management, boost target voltage determination and boost PI control. The specific content is as follows: Boost mode control. Boost mode includes initial mode, normal mode, off mode and fault mode. Boost target voltage is determined. Boost converter is controlled by variable voltage, which depends on the operation status of the motor and generator.. In order to improve the overall performance of the voltage control strategy, the voltage control strategy of the boost converter is dynamically adjusted by feeding the motor running state to the converter in real time, and the bus voltage is optimized. The motor application of the FOC strategy in the hybrid power system is the battery thermal control. The specific content is as follows: SVPWM control. SVPWM is based on the ideal flux loop of the three-phase symmetric motor stator powered by the three-phase symmetric sinusoidal wave as the reference standard, and the appropriate switching is carried out with different switching modes of the three-phase inverter, so as to form PWM waves and form actual flux vectors to track their accurate flux loops. Pulse thermal control. By applying the reactive voltage with high frequency changes and adopting the FOC control strategy, the inductive characteristics of the motor winding are constantly used to generate AC current on the bus. The high internal resistance of the battery at low temperature is used to constantly generate Joule heat on the battery. While avoiding the risk of lithium analysis on the battery, the battery itself will generate heat, thus increasing the temperature of the battery. Finally, the real vehicle test is carried out to verify the correctness of the motor control design.
Effect of Side Door Check Arm Profile on Side Door Closing Velocity
Authors: Keshav T J Sharath , Selvan Veera , Unadkat Siddharth , Subbaiyan Prasanna Balaji , Pandurangan Venugopal , Nizampatnam Balaramakrishna
Published: April 2024

The side-door operation of vehicle is vital to the customer, as it reflects the overall build quality of the vehicle. The side door check arm is one of the primary components that determine the operating characteristics of a vehicle door. The profile of the check arm has a significant impact on the closing effort of side doors. In this study, the check arm profiles are analyzed virtually in relation to the side door's closing velocity. A virtual door model was developed in ADAMS to simulate the side door closing and opening. The study involves a check arm that guides the ball spring mechanism housing unit over the guide profile. Typically, a check-arm guide profile has two or three indents at a specific location which serves to maintain the door open in those positions. When a door enters an indent, the user must exert an effort to traverse it. Furthermore, the slope profile of the check arm defines the self-closing assist offered from the initial indent to the latching position. By modifying this slope profile, the velocity of self-closing assist is optimized. Multiple iterations on this slope profile of the check arm are examined. The study revealed that the acute slope profile depicted by a brachistochrone curve provides better door closing velocity in check-arm. This study concludes that the slope profile of the check-arm can be optimized and defined for the maximum assist in door self-closing. It was demonstrated that the complete profile of the side door check arm can be designed and optimized to accomplish the desired door closing velocity.
Modeling and Control Strategy for Engine Thermal Management System
Authors: Jiang Chun-Hong , Wang Xihui , Wang Xinling , Duan Yaolong , Shangguan Wen-Bin
Published: April 2024

In order to study the influence of engine silicone oil fan clutch on the performances of engine cooling system under different control strategies, a model of engine cooling system for light truck is established. The working characteristics of the silicone oil clutch and the measured performance parameters of the cooling system components are taken into account in our proposed model. Modeling methods for different silicone oil fan control strategies are also given. Using the established model, the performance parameters under different vehicle speeds, such as coolant temperature of engine outlet and power consumption of cooling fan, are calculated and analyzed. The in-suite measurement of the engine cooling system is carried out to get the temperatures of engine coolant inlet and outlet from engine ECU. The model is validated by the comparison between the calculation and the measured results. Based on the established model, the working characteristics of different control forms of silicone oil clutch are analyzed, and an adaptive fuzzy PID control strategy is proposed for the controlled silicone oil clutch. Compared with the two-speed silicone oil clutch based on air temperature control and the electronically controlled silicone oil clutch based on PID controller control, the results show that the adaptive fuzzy PID controller established in this paper can reduce the power consumption of the cooling fan by 26.1% and 10.7% , if the vehicle runs under heavy-duty commercial vehicle test cycles (CHTC) .The modeling and analysis method in this paper can be used for the development and optimization of silicone oil clutch control strategy.
Impact Strength Analysis of Body Structure Based on a MBD-FEA Combined Method
Authors: Zhou Shuai , Liu Huaiju , Zhu Caichao , Yu Huili , Zhou Yunping , Ran Chunjiang , Guan Xuexue
Published: April 2024

In the field of automobile development, sufficient structure strength is the most basic objective to be accomplished. Typically, method of strength analysis could be divided into static strength and dynamic strength. Analysis of static strength constitutes the major part of the development, but the supplement of dynamic strength is also dispensable to assure structural integrity.

This paper presents a methodology about analyzing the impact strength of body structure based on a Multi-body Dynamics (MBD) and Finite Element Analysis (FEA) combined method.

Firstly, the full vehicle MBD model consists of Curved Regular Grid (CRG) road model, Flexible Ring Tire (FTire) model and dynamic deflection-force bump stop model was built in Adams/Car. Next, Damage Initiation and Evolution Model (DIEM) failure criteria was adopted to describe material failure behavior. Besides, six groups of specimens including tensile, R5, R20, shear, T-shear and punch were designed to identify parameters of the DIEM model. Then, misuse condition test on the Impact road was conducted by test vehicle equipped with Six-Axes Wheel Force Transducer (WFT) and corresponding experimental data were correlated with MBD simulation results to check the accuracy. Finally, an explicit dynamic analysis of body was performed in Abaqus to investigate the structural misuse behavior.

On the whole, simulation results of loads and structure response are in good accordance with experiment. Noticeable plastic deformations on the top mount area of body were observed and macroscopic fracture generated on the ribs of upper mounting seat was very close to that of real failure state.
Method for Root Bending Fatigue Life Prediction in Differential Gears and Validation with Hardware Tests
Authors: DeJack Michael A. , Tichy Richard
Published: April 2024

An advanced multi-layer material model has been developed to simulate the complex behavior in case-carburized gears where hardness dependent strength and elastic-plastic behavior is characterized. Also, an advanced fatigue model has been calibrated to material fatigue tests over a wide range of conditions and implemented in FEMFAT software for root bending fatigue life prediction in differential gears. An FEA model of a differential is setup to simulate the rolling contact and transient stresses occurring within the differential gears. Gear root bending fatigue life is predicted using the calculated stresses and the FEMFAT fatigue model. A specialized rig test is set up and used to measure the fatigue life of the differential over a range of load conditions. Root bending fatigue life predictions are shown to correlate very well with the measured fatigue life in the rig test. Also fatigue life predictions are shown to correlate well with validation tests carried out on a full-scale axle.
Efficient Fatigue Performance Dominated Optimization Method for Heavy-Duty Vehicle Suspension Brackets under Proving Ground Load
Authors: Tong Jiachi , Meng Dejian , Wang Lei , Gao Yunkai , Yang James
Published: April 2024

Lightweight design is a key factor in general engineering design practice, however, it often conflicts with fatigue durability. This paper presents a way for improving the effectiveness of fatigue performance dominated optimization, demonstrated through a case study on suspension brackets for heavy-duty vehicles. This case study is based on random load data collected from fatigue durability tests in proving grounds, and fatigue failures of the heavy-duty vehicle suspension brackets were observed and recorded during the tests. Multi-objective fatigue optimization was introduced by employing multiaxial time-domain fatigue analysis under random loads combined with the non-dominated sorting genetic algorithm II with archives. While evaluating fatigue life within optimization loops, particularly for multiaxial random load fatigue in the time domain, is time-intensive, this study is to improve computational efficiency in two strategies: 1) the dynamic adjustment of target nodes from the finite element model, using a weighted sum prior to performing fatigue damage prediction, 2) considering the actual cracking positions observed during the durability test, weld seams, identified as high-risk areas, were incorporated into the fatigue life prediction and optimization process. The fatigue evaluation results were in alignment with durability test outcomes of the suspension brackets, and the final optimization results were explored in both design and objective fields. The Pareto front was then utilized to show the trade-off between the conflicting objectives of lightweight design and enhanced fatigue performance to meet the enhanced durability requirements. This underscores the methodology's practicality and reliability in improving the durability and lightweight performance of suspension components.
Multi-Material and Multi-Objective Topology Optimization Considering Crashworthiness
Authors: Huang Yuhao , Shi Yifan , Morris Zane , Teoli Mira , Tameer Daniel , Kim Il Yong
Published: April 2024

Recently, topology optimization (TO) has seen increased usage in the automotive industry as a numerical tool, greatly enhancing the accessibility and production-readiness of optimal, lightweight solutions. By natural extension of classic single material TO (SMTO), a wealth of research has been completed in multi-material TO (MMTO), enabling simultaneous determination of material selection and existence. MMTO is effective for linear static analyses, making use of structural responses that are continuously differentiable, giving itself to efficient gradient-based optimization engines. A structural response that is inherently nonlinear and transient, thus providing difficulty to the mainstay MMTO process, is that of crashworthiness. This paper presents a multi-objective MMTO framework considering crashworthiness using the equivalent static load (ESL) method. The ESL method uses a series of linear static sub-models to approximate the transient crashworthiness model. Then, the sub-models can be optimized sequentially, using a conventional MMTO program. The limitations of the existing framework are: (1) its sole focus on intrusion minimization using displacement constraints, (2) some results have checkerboard patterns despite the use of a filter. In this paper, an improved framework aims to support the weighted sum of multiple objectives such as compliance and aggregated stress, which would affect multiple performance metrics, such as intrusion, deceleration, and energy absorption. Also, the ESL load generation method is updated to reduce checkerboarding. Firstly, the MMTO theory and ESL method are introduced. Second, the operational flow of the framework is discussed. Finally, the multi-objective solutions of an example academic model are compared using Pareto Frontiers. The optimized results show 6.4% reduction of maximum intrusion and 1.5% reduction of maximum deceleration.
Hardware-in-the-loop Experimental Platform Design for a Novel Electrically Interconnected Suspension System
Authors: Xia Xiangjun , Liu Pengfei , Li Weihua , Du Haiping , Ning Donghong
Published: April 2024

The suspension system plays a crucial role in mitigating vehicle vibration, enhancing passenger comfort, and improving driving handling stability. While many mechanical experimental platforms exist for testing suspension system performance, they often need high costs and precision requirements. In the field of modern industrial product design, hardware-in-the-loop (HIL) simulation has become an invaluable tool.

Electrically interconnected suspension (EIS) is a novel type of interconnected suspension by connecting various suspensions in an electrical way. The novel EIS avoids many drawbacks of traditional interconnected suspensions. The EIS is usually composed of electromagnetic motors and electrical networks (EN). By designing the structure of the EN reasonably, the EIS system can achieve decoupling control in multiple vibration modes.

This paper introduces an HIL experimental platform established for a half-car EIS system based on an NI Compact RIO 9049. The half-car electrically interconnected suspension model runs in the FPGA component, responsible for data collection and actuation control of the EIS. Simultaneously, the real-time component records data and manages the suspension circuit. The hardware of the HIL system comprises a new type of EIS system and corresponding control circuits.

The experimental results highlight the remarkable consistency between the HIL platform and the simulation model in Simulink, demonstrating a simplified and effective approach to experimental system design. Furthermore, the semi-active EIS shows superior vibration control performance compared to the passive EIS suspension, showcasing the benefits of decoupling control.
Modeling and Experimental Testing Analysis of Static and Dynamic Characteristics of Air Springs
Authors: Zhuo Yi-Fan , Wang Xihui , Li Jianxiang , Shangguan Wen-Bin
Published: April 2024

In order to study the effects of different factors on the static and dynamic characteristics of air springs, three models were established to calculate the static and dynamic characteristics of air springs, including modeling at the design position, modeling only considering the straight state, and modeling considering the thickness of the bellows in the straight state. Static stiffness of air springs is calculated using three different models and are compared with experiments. In the straight state model considering the thickness of the bellow, the influence of aluminum tube and bellows thickness on the static stiffness are considered, and the modeling with the straight state solved the problem of the change in cord angle after the air spring was inflated and expanded. The established model is then used to calculate static and dynamic characteristics of air springs, such as static stiffness, hysteresis loop, and dynamic stiffness. The static stiffness, force versus displacement hysteresis loop, and dynamic stiffness of the air spring at design position are measured. The comparison of the calculation and experimental results showed that the result of modeling considering the thickness of the bellows in the straight state was more accurate, and the maximum relative error of static stiffness is less than 5%. The modeling and analysis methods in this article can predict the static and dynamic characteristics of air springs, providing guidance and reference for designing the static and dynamic characteristics.