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Though modal analysis is a common tool to evaluate the dynamic properties of a structure, there are still many individual decisions to be made during the process which are often based on experience and make it difficult for occasional users to gain reliable and correct results. One of those experience-based choices is the correct number and placement of reference points. This decision is especially important, because it must be made right in the beginning of the process and a wrong choice is only noticeable in the very end of the process. Picking the wrong reference points could result in incomplete modal analysis outcomes, as it might make certain modes undetectable, compounded by the user's lack of awareness about these missing modes. In the paper an innovative approach will be presented to choose the minimal number of mandatory reference points and their placement.

The machining process is employed to transform a workpiece into a predefined geometry with the assistance of a cutting tool. Throughout this process, the cutting tool undergoes various adverse effects, including deformation, stress, thermal gradient, and more, all of which impact tool sharpness, surface finish, and tool life. These outcomes are also influenced by cutting parameters, specifically cutting speed, feed rate, and depth of cut. The present investigation aims to demonstrate the application of ANSYS analysis software in predicting stress, deformation, thermal gradient, and other factors on the tool insert tip for various machining parameters. To achieve this, an experimental setup was arranged to collect cutting force and temperature data using a dynamometer and thermocouples during the machining process of maraging steel with a tungsten carbide tool insert. Experiments were conducted with different combinations of machining parameters using design of experiments (DoE).

A variety of structures resonate when they are excited by external forces at, or near, their natural frequencies. This can lead to high deformation which may cause damage to the integrity of the structure. There have been many applications of external devices to dampen the effects of this excitation, such as tuned mass dampers or both semi-active and active dampers, which have been implemented in buildings, bridges, and other large structures. One of the active cancellation methods uses centrifugal forces generated by the rotation of an unbalanced mass. These forces help to counter the external excitation force coming into the structure. This research focuses on active force cancellation using centrifugal forces (CFG) due to mass imbalance and provides a virtual solution to simulate and predict the forces required to cancel external excitation to an automotive structure. This research tries to address the challenges to miniaturize the CFG model for a body-on-frame truck.

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.

Model-based developments have been introduced to reduce the development time for vehicle systems. Various model-based tools, including MATLAB and Simulink, have been introduced, and each vehicle component uses different tools to model assets. This makes the system complex and reduces the simulation efficiency because of the need for interfaces or converters when reusing model assets and combining parts. However, machine learning, in which neural nets are pretrained to make inferences in real time, is being applied to automatic driving and applications such as object recognition. This study developed a system in which the inputs and outputs assigned to a model were trained using neural nets, and the trained neural nets were combined with UML: Unified Modeling Language. A previous UML integration proposal integrated C/C++ code automatically generated from the models. Therefore, the previous proposal made limited use of modeling tools with automatic code generation capabilities.

The AutoDrive Challenge competition sponsored by General Motors and SAE gives undergraduate and graduate students an opportunity to get hands-on experience with autonomous vehicle technology and development as they work towards their degree. Michigan Technological University has participated in the AutoDrive Challenge since its inception in 2017 with students participating through MTU’s Robotic System Enterprise. The MathWorks Simulation Challenge has been a component of the competition since its second year, tasking students with the development of perception, control and testing algorithms using MathWorks software products. This paper presents the pedagogical approach graduate student mentors used to enable students to build their understanding of autonomous vehicle concepts using familiar tools. This approach gives undergraduate students a productive experience with these systems that they may not have encountered in coursework within their academic program.

This paper reviews the current situation in the development of accelerated testing of automotive engineering, consisting of the four following areas: 1. Field testing of the natural product. 2. Additional technology of separate testing in the laboratory on the basis of physical simulation of separate field conditions using corresponding methods and equipment separately and conducting: safety testing, special programs of testing using digital simulation, special testing with changing certain parameters of environment, corrosion testing, etc. Both of the traditional testing developments above can be found in many magazines, journals, conferences, presentations, and proceedings. 3. Testing on the basis of digital (computer) simulation of product and/or field conditions. This area of testing has been developed in the last dozen years. Many articles and presentations were published during this time. 4.

​Composites made of continuous fibers generally have higher strength-to-weight ratios in fiber directions as compared to those made of discontinuous fibers. However, the latter tend to display quasi-isotropic properties which can be of advantage when directions of mechanical loading can vary. For many real-world applications such as robust design of vehicle body components for crashworthiness, impact loads are stochastic in nature both in terms of magnitude and direction. Hence, in order to realize the true potential of laminated composites with continuous fibers, instead of orthotropic laminates which are most common due to the ease of design and manufacturing, angle-ply laminates are necessary.

The study and application of Topology Optimization (TO) has experienced great maturity in recent years, presenting itself as a highly influential and sought-after design tool in both the automotive and aerospace industries. TO has experienced development from single material topology optimization (SMTO) to multi-material topology optimization (MMTO), where material selection is simultaneously optimized with material existence. Today, MMTO for standard structural optimization responses are well supported. An additional and vital response in the design of structures is that of stress. Stress-driven or stress-controlled optimization techniques for SMTO are well understood and have been well-documented, evidenced by both published works and its availability in multiple commercial solvers. However, its integration into MMTO frameworks has not yet achieved reliable levels of accuracy and flexibility.

In this study, a novel selective matching logic for a wheel/tire is proposed, to decrease the vehicle driving vibration caused by wheel/tire non-uniformity. The new logic was validated through matching simulation/in-line matching evaluation. A theoretical radial force variation model was established by considering the theoretical model of the existing references and the wheel/tire assembly mechanism. The model was validated with ZF’s high-speed uniformity equipment, which is standard in the tire industry. The validity of the new matching logic was verified through matching simulation and mass production in-line evaluation. In conclusion, the novel logic presented herein was demonstrated to effectively decrease the radial force variation caused by the wheel/tire.

In the ever-evolving landscape of automotive technology, the need for robust security measures and dependable vehicle performance has become paramount with connected vehicles and autonomous driving. The Unified Diagnostic Services (UDS) protocol is the diagnostic communication layer between various vehicle components which serves as a critical interface for vehicle servicing and for software updates. Fuzz testing is a dynamic software testing technique that involves the barrage of unexpected and invalid inputs to uncover vulnerabilities and erratic behavior. This paper presents the implementation of fuzz testing methodologies on the UDS layer, revealing the potential vulnerabilities that could be exploited by malicious entities. By employing both open-source and commercial fuzzing tools and techniques, this paper simulates real-world scenarios to assess the UDS layer’s resilience against anomalous data inputs.

Wound rotor synchronous machines (WRSM) without rare-earth magnets are becoming more popular for traction applications, but their potential in drive performance has not yet been fully explored. This paper presents a Pulse Width Modulation (PWM) scheme optimization procedure to minimize motor and inverter losses. It leverages different PWM schemes with different PWM switching strategies and switching frequencies. First, a generic PWM-induced motor loss calculation tool developed by BorgWarner is introduced. This tool iteratively calculates motor losses with PWM inputs across the entire operating map, significantly improving motor loss prediction accuracy. The inverter losses are then calculated analytically using motor and wide-bandgap (WBG) switching device characteristics. By quantifying these various scenarios, the optimal PWM scheme for achieving the best system efficiency across the entire operating map is obtained.

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.

Efficient transportation for carrying heavy loads is a common challenge across various applications, from supermarkets to industrial purposes. Conventional trolleys often fall short when loaded with heavy cargo, resulting in increased exertion and diminished productivity. Moreover, these challenges can adversely affect posture and lumbar spine health, especially for elder people and persons with cervical problems. There is a need for more user-friendly, ergonomic, and space-efficient solutions. This project addresses these challenges through an innovative design that encompasses various aspects of trolley functionality, including the study of comfort, wheel selection, and material considerations, drawing from ergonomic research. Multiple methods are employed to optimize the trolley’s dimensions to improve its overall performance. The trolley’s design features a collapsible basket for the transport of smaller-sized items and a base frame for larger goods and luggage.

The use of electrical contacts in aerospace applications is crucial, particularly in connectors that transmit signal and power. Crimping is a widely preferred method for joining electrical contacts, as it provides a durable connection and can be easily formed. This process involves applying mechanical load to the contact, inducing permanent deformation in the barrel and wire to create a reliable joint with sufficient wire retention force. This study utilizes commercially available Abaqus software to simulate the crimping process using an explicit solver. The methodology developed for this study correlates FEA and testing for critical quality parameters such as structural integrity, mechanical strength, and joint filling percentage. A four-indenter crimping tool CAD model is utilized to form the permanent joint at the barrel-wire contact interfaces, with displacement boundary conditions applied to the jaws of the tool in accordance with MIL-C-22520/1C standard.

The scope of the study was to understand the mechanical behavior of a retainer design - used to attach an exterior part on the body structure - during insertion and retention events and it was performed with the extensive use of finite elements tools, more specifically, LS-Dyna, a powerful FE tool able to run both explicit and implicit structural analyses commonly used in automotive developments to simulate dynamic events, such as high speed impacts. Several FE models were used to define best methodology in terms of modeling technic and contact representation. Additionally, based on physical tests, it was able to achieve a good virtual representation of the retainer forces and visualize each step of these events. These data were used to identify what dimensional parameters of the retainer were more important to “tune” the part performance. As conclusion, a new design was proposed able to reduce the insertion force about 43% with no decrease in the retention force.

The Mobile Progressive Deformable Barrier (MPDB) is a standardized automotive crash scenario that comprehensively evaluates the safety of battery-electric vehicles (BEVs) in a crash. In an accident, the deformation pattern of the Front of Battery Electric Vehicle (FOBEV) structure, the efficiency of energy absorption, the acceleration pulse, and the degree of intrusion into the passenger compartment combine to affect the safety of the driver and passengers. In order to simulate and calculate the damage state of FOBEV in MPDB more efficiently and to construct a collision damage dataset in the entire velocity domain, a FOBEV equivalent model is proposed. The acceleration pulses from numerical simulations and impact tests were compared to verify the model’s validity.

SAE J1978-1 specifies a complementary set of functions to be provided by an OBD-II scan tool. These functions provide complete, efficient, and safe access to all regulated OBD (on-board diagnostic) services on any vehicle which complies to SAE J1978-1 The SAE J1978-1 content of this document is intended to satisfy the requirements of an OBD-II scan tool as required by current U.S. on-board diagnostic (OBD) regulations. This document specifies: A means of establishing communications between an OBD-equipped vehicle and an OBD-II scan tool. A set of diagnostic services to be provided by an OBD-II scan tool in order to exercise the services defined in SAE J1979 and SAE J1979-2. The presentation of the SAE J1978 document family, where SAE J1978-1 covers first generation protocol functionality defined in SAE J1979, and SAE J1978-2 covers second generation protocol functionality defined in SAE J1979-2.

The requirement of the current scenario is to identify the sustainable material and process it into acceptable properties for current applications. The natural fiber is a prime sustainable material having the properties of biodegradability, plenty of availability, economical and adequate physical-mechanical property. Sesbania rostrata fiber is extracted from the stem of Sesbania rostrata plant which is cultivated along with Turmeric plants on 1000 acres annually as a nitrogen fixation plant. The fiber-reinforced composite is a tailor made material by altering the fiber and polymer weight proportion to achieve desired properties for applications. The natural fiber is a promising material to replace synthetic fiber to transform the composite into biodegradable. The making of holes in the biocomposite by the secondary process is essential for the assembly operation.

In India, agriculture is a vital part of the country’s economy and almost everything depends on it. It takes a lot of time and effort for the farmer to remove the leftover root vegetables and crops in soil. Even after manually removing these crops, they can’t fully recover the leftover thing. This process takes more time and is challenging for the farmer. Due to human error, around 20-30% of the crops and root crops are left out in the field. Unfortunately, poor farmers can’t afford the necessary equipment to remove these crops. Generally, Root crops are cultivated by root crop harvester through diggers present under the chassis in the middle which are seen randomly by operators and cultivated or else through cameras which are highly cost and not affordable by all the farmers, hard to maintain and not technically strong by the farmers to operate the cameras.