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The paper discusses the process of developing an SAE damping measurement test method that is suitable for testing bars that are not made of steel or are difficult to measure with the traditional Oberst bar method. The method is based on measuring mechanical impedance (force over velocity) of a vibrating bar. The bar is excited at the center using a shaker and hence it is also called a CenterPoint method. The paper discusses the round robin tests that have been conducted so far and discusses the test results that will help develop the standard. The paper discusses the variability of the round robin test results within a laboratory, between laboratories, as well as the coefficient of variation for these measurements. The paper also discusses various parameters that should be carefully monitored in this study, that otherwise could affect the precision of the test procedure.

As part of the update process to SAE J1637, “Laboratory Measurement of the Composite Vibration Damping Properties of Materials on a Supporting Steel Bar”, the Acoustical Materials Committee commissioned a round robin study to determine the current laboratory-to-laboratory variation, and to better understand best practices for composite loss factor measurements. Guidance within the current standard from a previous round robin study indicates a coefficient of variation of 35% for laboratory-to-laboratory measurements. It was hoped that current instrumentation and test practices would yield lower variability. Over the course of 5 years, 10 separate laboratories tested 4 bars: three damped steel bars and one bare steel bar. The bars were tested at -20°C, -5°C, 10°C, 25°C, 40°C, and 55°C. The damping materials were intentionally selected to provide low damping, moderate damping, and high damping to illustrate difficulties in determining the composite loss factor with increased damping.

To reduce the noise in the frequency range of 100Hz~1000Hz, a metamaterial structure composed of lightweight frame, hard membrane-like material and added mass is proposed in this paper. The advantage of this structure is that it is lightweight and the membrane-like material does not need to be stressed in advance. Finite element method (FEM) and experiment are used to investigate the sound transmission loss (STL) performance of the metamaterial structure. The results show that the peak STL is caused by the local resonance of the added mass and the membrane-like material. The valley versus frequency results from the resonance frequencies of metamaterial structure, and it is divided into three resonance frequencies: resonance frequencies from added mass, membrane-like material and frame.

A high compression ratio is an effective means for improving the thermal efficiency of an internal combustion engines. However, a high compression ratio leads to a rapid rise in the combustion pressure, as it causes a high impulse force. The impulse force generates vibrations and noise by spreading in the engine. Therefore, reducing the vibration of the combustion (which increases as the compression ratio increases) can improve the thermal efficiency while using the same technology. We are conducting model-based research on technologies for reducing combustion vibration by applying a granular damper to a piston. To efficiently reduce the vibration, we suppress it directly with the piston, i.e., the source of the vibration. Thus, the damping effect is maximized within a minimized countermeasure range.

Automotive industry is looking for high strength and durable lightweight material with resistance to wear and friction. To meet this requirement, a new hybrid polymer composite material has been developed using reinforcement as SS 304 wire mesh and jute fibre. Present paper explores the experimental findings of wear performance of hybrid polymer composite under dry condition. Four different laminates with configurations JJSJJSJJ, (JJSJJSJJ)450, GGSGGSGG and GJSJJSJG along with their virgin counterpart were developed by hand layup technique supported by compression moulding. These laminates were tested as per the ASTM standards to investigate its performance for friction and wear using pin on disc machine with steel as a counterpart. Testing parameters were sliding distance, applied load and sliding speed. Experimental results showed that, applied load have major influence on the friction and wear performance of developed hybrid composites.

Vibration control plays a critical role in conventional as well as next-generation vehicles. Construction of the vehicle, road conditions, and driving patterns are the major sources of the vibrations that cause discomfort to the passengers in the vehicle. Composite material is being looked at as an alternative material in the automotive sector due to its higher specific strength and good damping properties. In this research, the test specimen of steel plate used in automotive has been considered. The damping vibration test has been carried out on the test specimen by using the FFT analyzer to evaluate the natural frequency and damping. Thereafter, the hybrid composite material is developed with the natural fibers as reinforcement with steel plate to reduce the vibrations. The test specimens with different layers of damping materials have been prepared for this research. Jute, hemp, banana, and flax are used for the preparation of different composite materials.

Access control enforces security policies for controlling critical resources. For V2X (Vehicle to Everything) autonomous military vehicle fleets, network middleware systems such as ROS (Robotic Operating System) expose system resources through networked publisher/subscriber and client/server paradigms. Without proper access control, these systems are vulnerable to attacks from compromised network nodes, which may perform data poisoning attacks, flood packets on a network, or attempt to gain lateral control of other resources. Access control for robotic middleware systems has been investigated in both ROS1 and ROS2. Still, these implementations do not have mechanisms for evaluating a policy's consistency and completeness or writing expressive policies for distributed fleets. We explore an RBAC (Role-Based Access Control) mechanism layered onto ROS environments that uses local permission caches with precomputed truth tables for fast policy evaluation.

The application of virtual engineering methods can streamline the product design process through improved collaboration opportunities among the technical staff and facilitate additive manufacturing processes. A product digital twin can be created using the available computer-aided design and analytical mathematical models to numerically explore the current and future system performance based on operating cycles. The strategic decision to implement a digital twin is of interest to companies, whether the required financial and workforce resources will be worthwhile. In this paper, two metrics are introduced to assist management teams in evaluating the technology potential. The usefulness and time savings metrics will be presented with accompanying definitions. A case study highlights the usefulness metric for the “Deep Orange” prototype vehicle, an innovative off-road hybrid vehicle designed and fabricated at Clemson University.

Now for past many decades, automotive manufacturing is under perennial pressure owing to consumer aspirations, regulations, globalized competition and sustainability needs. Automotive manufactures are fiercely satisfying all of above constraints through innovative solutions. The resultant vehicles have many complex to very complex systems and subsystems to deliver the performance aspirations. In this game, one of the critical business parameter is rapid time to market. At the current state of the art, time to market directly conflicts with new product development time. Four wheeler new product development consumes upward of 48 months, while risking obsolescence of product features at the time of launch. Automotive manufacturers invest intensely in technologies to achieve this goal of short time to market. Digital technologies delivering high time efficiency have made deep in roads in the automotive product development arena.

Fretting fatigue was observed in standard cylindrical fatigue samples at the regions in contact with the grips of the test frames during fatigue testing for AlSi10Mg aluminum alloy produced by laser powder bed fusion process (L-PBF). The failure of the fatigue sample grips occurs much earlier than the failure of the gauge section. This results in a damaged sample and the sample cannot be reused to continue the test. This type of failure is rarely seen in materials produced by traditional manufacturing processes. In this study, X-ray residual stress analysis was performed to understand the cause of failure for L-PBF AlSi10Mg with the as-built surface condition. The result indicates that the fretting fatigue failure was caused by the strong tensile residual stress in the as-built state combining with the fretting wear between the sample and the grip. A few potential solutions to avoid the fretting fatigue failure were investigated.

Additive Manufacturing (AM) using stereolithography (SLA) was applied to produce engine O-rings using two different flexible polymer printing materials, Flex 80A and Elastic 50A. Print orientation of the O-ring in the SLA 3D printer is important, with the horizontal configuration most commonly providing for the smoothest final O-ring printed surface due to the lack of printing support tabs required. AM printing tabs lead to O-ring ‘marks’ (non-smooth surfaces) that were evaluated using the Society of Automotive Engineers SAE AS871B standard. It was seen that numerous printing approaches produced ‘marks’ that were larger than acceptable, which shows that these studied AM processes can not replace traditional methods of O-ring manufacture. However, further evaluation was pursued to explore possible remote emergency usage of these O-rings. Printed O-rings were next tested-soaked in engine related fluids in order to characterize O-ring swelling behavior.

Compared with traditional welding, self-piercing riveting technology has unique advantages and is widely used in automobile lightweight technology. The riveting quality of self-piercing riveting is closely related to the safety and durability of automobiles. The detection of riveting quality has gradually become an important part of the automobile manufacturing process. The generation of surface cracks under self-piercing riveting will affect the riveting strength, which in turn affects the riveting quality. Therefore, the detection of riveting external quality is transformed into the detection of riveting surface cracks. The existing artificial vision-based riveting lower surface crack recognition technology is inefficient, subjective and cannot be applied on a large scale. Therefore, this paper will propose a local-overall strategy based on image processing and computer vision.

In order to sustain in automobile industry, fuel economy and robustness are playing vital role in vehicle. Every gram of weight will have an impact on fuel economy, thus burning a hole in consumers pocket and contributing heavily to the carbon footprint. Composite material development plays important role in meeting the stringent self-imposed targets of the automotive manufacturers and light weighting is becoming a prime option for improving Fuel Economy. The main objective of this paper is to optimize the weight of the luggage lid floor and reduce its cost without compromising on the strength by changing the raw material and manufacturing process. This part is in trunk compartment of the vehicle. Main function of this part is to withstand the luggage load under various user loading patterns at varied temperature and while driving on different road conditions.

New highly ductile AHSS steel grades with tensile strength greater than 980 MPa have been developed with the aim of combining high strength and excellent formability. The new jetQ-Family offers high local and global ductility while still fulfilling standards for resistance towards hydrogen embrittlement and weldability. These improved properties are based on their specifically engineered microstructure, which utilize the TRIP-mechanism in a strengthened matrix. This work shows how the microstructure plays a significant role for the tensile testing as well as hole-expansion. Based on the increased yield strength a better crash performance compared to conventional DP steel grades can be attained. The local ductility is demonstrated with excellent hole expansion ratios and high resistance to sheared edge failure. In combination with improved bending angles and thickness strain at fracture a robust process for manufacturing of components can be achieved.

The tractor usage is growing in the world due to derivative of rural economy and farming process. It needed wide range of implements based on the applications of the customer. The tractor plays a major role in Agricultural and Construction applications. In a tractor, hydraulic system is act as a heart of the vehicle which controls the draft and position of the implement. Hydraulic system consists of Powertrain assembly, 3-point linkage and DC sensing assembly. The design of hydraulic powertrain assembly is challenging because the loads acting on the system varies based on the type of implement, type of crop, stage of farming and soil conditions etc., Hydraulic powertrain assembly is designed based on standards like IS 12207-2019 which regulates the test methods for the system based on the lift capacity of the tractor. In this paper, virtual simulation has been established to optimize the design and perform the test correlation.

In an off-road vehicle, Vehicle Structure plays a major role in passenger safety, Aesthetics, Durability, through a validated construction of canopy structure. This structure is to maintain the shape of the vehicle and to support various loads acting on the vehicle. In present market a safe, Durable, Robust, Waterproof, Noise less, Light weight and cost-effective off-road vehicle will always be a delight for any customer. However, the current conventional way of Soft top vehicle structure use metal brackets and formed sheet parts to create a structure to retain the canopy shape in place. These conventional structures are often heavier and would have many demerits such as heavy weight, Corrosion, Risk of canopy tear due to metallic structure edges and inappropriate draining, water management. Considering this we replaced the heavy metal brackets in to blow molded plastic parts.

Light weight technologies are inevitable in the automotive industry to increase fuel efficiency and meet emission norms. An engine cylinder block is one of the major elements contributing approximately 3-4 % of the automobile weight. Aluminum cylinder block with cast-in liner is almost 40-55 % lighter than a conventional cast iron block [1] and hence the manufacturing processes and challenges associated with them are of high interest. A heterogeneous cast-in liner of gray cast iron in cast aluminum offers a low cost option, but the mechanical bond created between the liner and aluminum interface is prone to gap formation which affects the engine in terms of in-effective heat transfer, distortion and higher blow-by, and thereby high oil consumption & higher emissions. This study aims at reducing this interface bonding gap by in-depth study of critical process parameters involved in manufacturing of cylinder blocks.

Welding deformation of aluminum alloy is an urgent problem to be solved, it affects the performance and service life of welding products. In this research, in order to compute welding deformation and residual stress, a finite element model of 6061-T6 aluminum alloy was established. The efficiency and the accuracy of the welding residual stress calculation and the welding deformation were significantly improved. By comparing the temperature field and the displacement field of simulation and experiment, the finite element model was validated. Through finite element analysis, Heat input and welding times have important effects on welding deformation and residual stress was found. The welding deformation law and the residual stress distribution law were proposed, after cooling of the welding seams, the plates collapsed to the other side of the heat source along the vertical direction, the welding deformation tendency was heightened by double-sided welding.

The use of lightweight materials is one of the important means to reduce the quality of the vehicle, which involves the connection of dissimilar materials, such as the combination of lightweight materials and traditional steel materials. The riveting quality of self-piercing riveting (SPR) technology will directly affect the safety and durability of automobiles. Therefore, in the initial joint development process, the quality of self-piercing riveting should be inspected and classified to meet safety standards. Based on this, this paper divides the self-piercing riveting quality into riveting appearance quality and riveting section quality. Aiming at the appearance quality of riveting, the generation of cracks on the lower surface of riveting will seriously affect the riveting strength. The existing method of identifying cracks on the lower surface of riveting based on artificial vision has strong subjectivity, low efficiency and cannot be applied on a large scale.

In present work prefabricated multi-material adaptors welded with solid state welding such as roll bonding were explored. Aluminium-Steel adaptor manufactured by roll bonding was used which also has a highly oxidation resistant interface layer which resist the formation of intermetallic. The bimetal adaptors were manufactured by a machining process which carve out the adaptors in required design and configurations from a flat multi-material plate. The bimetal adaptors were used to join aluminium extrusion to steel by arc welding. The Steel side of multi-material adaptor is arc welded with steel and Aluminium side is arc welded with aluminium extrusion tube. This resulted into fabrication of a lightweight multi material joint with aluminium tube and steel. Secondary arc welding process was optimized to keep the interface of primary solid state welded adaptor below 350 Deg C.