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SAE J3078 provides test methods and criteria for the evaluation of the operator enclosure environment in earth-moving machinery as defined in ISO 6165. SAE J3078/1 gives the terms and definitions which are used in other parts of SAE J3078. It is applicable to Off-Road Self-Propelled Work Machines as defined in SAE J1116 and tractors and machinery for agriculture and forestry as defined in ANSI/ASAE S390.

The current focus in the ongoing development of autonomous driving systems (ADS) for heavy duty vehicles is that of vehicle operational safety. To this end, developers and researchers alike are working towards a complete understanding of the operating environments and conditions that autonomous vehicles are subject to during their mission. This understanding is critical to the testing and validation phases of the development of autonomous vehicles and allows for the identification of both the nominal and edge case scenarios encountered by these systems. Previous work by the authors saw the development of a comprehensive scenario generation framework to identify an operating domain specification (ODS), or external and internal conditions an autonomous driving system can expect to encounter on its mission to form critical scenario groups for autonomous vehicle testing and validating using statistical patterns, clustering, and correlation.

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.

Nowadays, Bismuth (Bi) is being applied as an overlay material for engine bearings instead of Lead (Pb) which is an environmentally harmful material. Bi overlay has already been a solid performer in some automotive engine sectors due to its superior load carrying capacity and good robustness characteristic which are necessary to maintain its longevity during the lifetime of engines. The replacement is also seen on relatively larger size engines, such as Trucks and Off-highway heavy duty applications. Basically, these applications require higher power output than passenger cars, and the expected component lifecycle becomes longer. Though Bi has similar material characteristic to traditional Pb, it becomes challenging for the material alone to satisfy these requirements. Polymer overlay is known for its superior anti-wear performance and longer lifetime due to less adhesion against a steel counterpart than metallic materials (included Bi).

Lithium-ion batteries serve as the main power source for contemporary electric vehicles. Safeguarding these batteries against damage is paramount, as it can trigger accelerated performance deterioration, potential fire hazards, environmental threats, and more. This study explores damage progression of a commercial vehicle lithium-ion battery module containing prismatic cells under indentation crush loading. We employed computational simulations of mechanical loading tests to investigate this behavior. Physical tests involved subjecting modules to low-speed (0.05 m/s) indentations using a V-shaped stainless-steel wedge, under six unique loading conditions. During the tests, force, and voltage change with wedge displacement were monitored. Utilizing experimental insights, we constructed a finite element model, which included key components of the battery module, such as the prismatic cells, steel frames, and various plastic parts.

The current battery carrier for commercial vehicles is made of steel and is designed to hold two batteries weighing approximately 80 kg to 100 kg. However, this battery carrier faces several issues including corrosion, chemical reactivity, high maintenance requirements and its heavy weight. To tackle these challenges, a fiber-reinforced composite battery carrier is designed and developed specifically for commercial vehicles. The objective is to identify a solution that can meet the performance requirements of both static and dynamic loading, thereby reducing the overall weight. The proposed composite battery carrier offers a lightweight design, requires minimal maintenance, possesses high tensile strength and stiffness and is corrosion and chemical resistant. Furthermore, it provides the flexibility to integrate battery cover locking arrangements for added convenience and security.

Building upon prior research, this paper compares computer simulations to a previously conducted rollover crash test of a tractor-semitrailer. The effects of torsional stiffness were elucidated during the correlation of simulations to the rollover test. A commercially available vehicle dynamics and reconstruction software was used for the simulation. Unique aspects of the rollover crash test were modeled in the simulation. A tractor-semitrailer quarter-turn rollover crash test conducted by IMMI was reconstructed using impact and vehicle dynamics models within the simulation software HVE (Human, Vehicle & Environment). The SIMON (SImulation MOdel Non-linear) module and the DyMESH (Dynamic MEchanical SHell) module within HVE were used. During the IMMI test, onboard instrumentation recorded acceleration and roll rate data in six degrees of freedom to characterize both tractor and semitrailer dynamics before and during the rollover event.

Wheel hubs with drum brakes of heavy-duty vehicles rarely broke, but some suddenly cracked in the 2000s. The cause of damage was said to be a lack of hub strength. However, the case was suspicious because the hubs were produced according to the design guidelines by the JSAE. In the 1990s, brake shoe-lining materials were changed from asbestos to non-asbestos for people’s health. The brake squeal and abnormal self-lock frequently occurred because of the increased friction coefficient between drum and shoe lining in the case of the leading–trailing type. The mechanical friction coefficient changes with the material and the contact angle, which varies with the wear of shoe lining and the drum temperature. In the previous report, the deformation of the wheel hub under the abnormal self-lock was verified by observing the change of hub attitude in model test equipment.

Dust testing of vehicles on unpaved roads is crucial in the development process for automotive manufacturers. These tests aim to ensure the functionality of locking systems in dusty conditions, minimize dust concentration inside the vehicle, and enhance customer comfort by preventing dust accumulation on the car body. Additionally, deposition on safety-critical parts, such as windshields and sensors, can pose threats to driver vision and autonomous driving capabilities. Currently, dust tests are primarily conducted experimentally at proving grounds. In order to gain early insights and reduce the need for costly physical tests, numerical simulations are becoming a promising alternative. Although simulations of vehicle contamination by dry dust have been studied in the past, they have often lacked detailed models for tire dust resuspension. In addition, few publications address the specifics of dust deposition on vehicles, especially in areas such as door gaps and locks.

Abstract The use of appropriate loads and regulations is of great importance in weld fatigue assessment of rail on-track maintenance equipment and similar vehicles for optimized design. The regulations and available loads, however, are often generalized for several categories, which proves to be overly conservative for some specific categories of machines. EN (European Norm) and AAR (Association of American Railroads) regulations play a pivotal role in determining the applicable loads and acceptance criteria within this study. The availability of track-induced fatigue load data for the cumulative damage approach in track maintenance machines is often limited. Consequently, the FEA-based validation of rail track maintenance equipment often resorts to the infinite life approach rather than cumulative damage approach for track-induced travel loads, resulting in overly conservative designs.

Aluminium composites are remarkably used in automotive, aerospace, and agricultural sectors because of their lightweight with definable mechanical properties. The stir casting route was followed to fabricate cylindrical samples with base aluminium alloy LM4, LM4/SiC, LM4/Al2O3, and LM4/SiC/Al2O3. The tensile strength, compressive strength, hardness, and micro-structural analysis were performed on samples and Finite element analysis (FEA) was adopted to predict the failure modes of composites. The composites experimental results were found to be in line with the FEA results, however, the LM4/SiC/Al2O3 revealed better results on the mechanical properties when compared with other composite configurations. The mechanical properties improvement like hardness 5%-11%, tensile strength 10.26%-20.67%, compressive strength 15.19% - 32.58% and 71.52 - 82.1% reduction in dimension have been achieved in LM4/SiC/Al2O3 composite comparing to base metal.

Lightweight materials are in great demand in the automotive sector to enhance system performance. The automotive sector uses composite materials to strengthen the physical and mechanical qualities of light weight materials and to improve their functionality. Automotive elements such as the body shell, braking system, steering, engine, battery, seat, dashboard, bumper, wheel, door panelling, and gearbox are made of lightweight materials. Lightweight automotive metals are gradually replacing low-carbon steel and cast iron in automobile manufacture. Aluminium alloys, Magnesium alloys, Titanium alloys, advanced high-strength steel, Ultra-high strength steel, carbon fiber-reinforced polymers, and polymer composites are examples of materials used for light weighing or automobile decreased weight. The ever-present demand for fuel-efficient and ecologically friendly transport vehicles has heightened awareness of lowering weight and performance development.

Aluminum alloys are employed in agricultural equipment, aerospace sectors, medical instruments, machinery, automobiles, etc. due to their physical and mechanical characteristics. The geometrical shape and size of the parts are modified in turning operation by using a single-point cutting tool. A356 aluminum alloy is widely used in various engineering sectors, hence there is a necessity to produce A-356 components with quality. The inappropriate cutting parameters used in turning operation entail high production costs and reduce tool life. Box–Behnken design (BBD) based on response surface methodology (RSM) was used to design the experiments such that the experiment trials were conducted by varying cutting parameters like N-spindle speed (rpm), f-feed rate (mm/rev), and d-depth of cut (mm). The multi-objective responses, such as surface roughness (SR) and metal removal rate (MRR) were analyzed with the desirability method.

When a specialty tractor is operated by mounting the front loader or backhoes, the loads are distributed proportionately to the front and rear axles. The maximum load and fatigue life were identified as the main parameters in predicting fatigue failure. This paper mainly focuses on predicting front axle loads and fatigue life in front loader applications. To design a new front axle for the loader application, an existing front axle assembly that was designed for orchard, sprayer, and small farm application is selected for study and to extend it for front loader application with minimal design modifications. The major challenge is to estimate the dynamic loads coming to the front axle due to the front loader application and validate it for a different set of load cases as per the design verification plan. Hence a methodology was framed to estimate the actual loads using MBD, validate with field measurements, and verify the new front axle design using those loads in FEA.

Commercial vehicle are exposed to harsh environment conditions like dust, mud, wind, rain, extreme sun and winter throughout. Apart from white goods and other conventional loading these vehicles also used in applications which involve Handling of Dirty Loads, Construction Raw materials, Mining Industry etc. which leads to fast deterioration of Interiors. Also, in most cases drivers are not the owners. Hence due to high cost of Cleaning at dealerships and low Product maintenance awareness amongst Commercial Vehicle Users, on Road Washing & Cleaning by riverside is common practice which leads to early deterioration of Interior trims. This paper deals with the retention of newness of soft trim parts such as headliner, wall trims and carpets. Causes of product deterioration and attributes which influence newness like product appeal, NVH, perceived quality, environmental impact, geometry retention over time etc. have been discussed in detail.

The commercial vehicle sector (especially trucks) has major role in economic growth of a nation. With improving infrastructure, increasing number of commercial vehicles and growing amount of Vulnerable Road Users (VRUs) on roads, accidents are also increasing. As per RASSI (Road Accident Sampling System India) FY2016-21 database, commercial vehicles are involved in 43% of total accidents on Indian roads. One of the major causes of these accidents is Driver Drowsiness and Inattention (DDI) (approx. 10% contribution in total accidents). This paper describes novel driver-in-loop performance assessment methodology for comprehensive verification of Driver Monitoring System (DMS) for commercial vehicle application. Novelty lies in specification of test subjects, driving styles and variety of road traffic scenarios for verification of DMS system. Test setup is made modular to cater to different platform environments (Heavy, Intermediate, Light) with minor modifications.

In the modern and fast growing automotive sector, reliability & durability are two terms of utmost importance along with weight & cost optimization. Therefore it is important to explore new technology which has less weight, low manufacturing cost and better strength. The new technology developed always seek for a quick, cost effective and reliable methodology for its design validation so that any modification can be made by identifying the failures. This paper presents the rig level test methodology to validate and to correlate the CAE derived strain levels, life cycle & failure mode of newly developed light weight stabilizer link for EV Bus suspension

In automotive industry, testing and validation teams are highly dependent on availability of prototype vehicles for testing and evaluation of ride & comfort behavior of vehicles. Special test tracks surfaces are also used (namely Tar road, Express way and driving over a Cleat) to evaluate the ride & comfort through subjective evaluation. Ride is largely affected by transmissibility of road excitations to the driver and other occupant’s seats, influence of suspension, bushes and tire are the major contributors in the transfer path of vibrations. A configurable 1–D simulation model of a Two Axle Truck is developed for quick evaluation of the ride & comfort behavior which is need of the hour for the testing team in optimizing the number of iterations in physical testing. These simulations will help in understanding the ride & comfort behavior and its sensitivity to changes in the component’s characteristics in absence of physical test vehicles.

Commercial transportation is the key pillar of any growing economy. Light and Small commercial vehicles are increasing every day to cater the logistics demand, but there is always a gap between customer’s actual and desired operational efficiency. This is because of lack of organized fleet and efficient fleet operation. The major requirement of fleet owners is timely delivery, high productivity, downtime reduction, real time tracking, etc., Automakers are now providing fleet management application in modern LCV & SCV to satisfy the fleet operator requirement. However, any feature malfunction, consignment mismatch, wrong notification, missed alerts, etc., can incur huge loss to fleet operator and disrupt the entire supply chain. Hence it is very critical to extensively validate the telematics features in fleet management application. This paper explains the approach for exhaustive validation strategy of fleet management applications (B2B) from end user perspective.

The Heavy Duty live rear axles in commercial vehicle helps to transmit the drive to the rear wheels and also carries vehicle load. The rear axle along with wheel assembly consists of axle casing, differential unit, half shafts, wheel hub, brake drum, brake chamber and wheels. It is one of the major safety critical element in any commercial vehicle. Based on the suspension type, rear axle housing also carries V rod & radius rod mountings & Spring Seat /Wear pad / Rubber Bolster (in case of bogie suspension). This paper abbreviates the contribution of bogie suspension seating configurations & V-rod Forces on life of heavy duty bogie rear axle casing. In-service DRT hot spot observations were reported on heavy duty rear axle on few models with bogie suspension. In order to find the root cause, devising a proper testing and analysis method is of prime importance. An extensive effort was made to device test methodology based on customer application and field visits.