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In the modern automotive sector, durability and reliability are two terms of utmost importance and relevance. The ever improving standards and cut throat competition has led to customers expecting highly reliable products at low costs. Any product that fails within its useful life leads to customer dissatisfaction and affects the OEM’s reputation. To eradicate this, all automotive components undergo stringent validation protocol, either in proving ground or in lab. Multipurpose bracket is one of the most important and critical aggregate in the vehicle assembly. It encompasses various mounting components such as FUPD bracket, steering mounting bracket, front spring front bracket, cab mount bracket, cab tilt cylinder mounting bracket, front cross member, footstep bracket and bumper. All these components experience various degrees of vibration and fatigue during its running period.

In the emerging commercial vehicle sector, it is very essential to give a product to customer, which is very reliable and less prone to the failures to make the product successful in the market. In order to make it possible, the product is to be validated to replicate the exact field conditions, where it is going to be operated. Lab testing plays a vital role in reproducing the field conditions in order to reduce the lead time in overall product life cycle development process. This paper deals with the design and fabrication of the steering column slip endurance test rig. This rig is capable of generating wear on the steering column splines coating which predominantly leads to failure of steering column. The data acquired from Proving Ground (PG) was analyzed and block cycles were generated with help of data analyzing tools.

In competitive vehicle market, the product must be designed and validated in shorter time span without compromising the quality. The durability of the vehicle is tested either by on road trials undertaken at the actual customer supplication sites for large time period or in the accelerated rough surfaces called “Proving ground” to validate in shorter time span. Accelerated proving ground durability testing plays a vital role in enabling shorter product development cycles by simulating the road load influences alone from the actual field conditions. It is imperative to simulate the test vehicle at proving ground (PG) testing such that it replicates the same damage that occurs in the field due to road loads. PG validation requires a specific durability test sequence for every segment of commercial vehicles due to different customer usage applications and terrain conditions. This diversity in applications and terrains induce structural damage at different range of frequencies.

Exhaust Gas Recirculation (EGR) is a method to control Nitrogen Oxide (NOx) emissions from automobile exhaust. In this method, small amount of the exhaust gas is recirculated into the combustion chamber through the air intake system. The exhaust gas is mixed with charge air just before entering intake manifold. Appropriate mixing of exhaust gas with charge air is necessary to ensure nearly equal amount of exhaust gas flow into all the cylinders. Present research efforts by various automobile manufacturers rely on commercial CFD simulation tools to identify and resolve flow and thermal issues occurring in various vehicle systems. The focus of this paper is to optimize the EGR system to obtain uniform distribution of recirculated exhaust gas to every cylinder of a six cylinder heavy duty diesel engine. CFD simulations were done for this engine using a commercial CFD solver. Mixing and transport of the two fluids was modeled using species transport approach.

In an era of global manufacturing and reduced costs, it is imperative that the manufacturing floor is visible to top management in a boardroom to enable them to make key decisions. Manufacturing Execution System (MES) is a method of connecting the shop floor to the top floor covering the complete gamut of activities from production sequence to finished goods. It aims to reduce the delay in transmitting production related data by linking the Production environment, Quality management, IT systems and Delivery. At Ashok Leyland’s Commercial Vehicle manufacturing facility in Ennore, India, an engine and axle components machine shop have been networked and data pertaining to production of Cylinder Block, Cylinder Head, Camshaft, Crankshaft, Axle Arm and Axle Beam components are accessible from anywhere in the company irrespective of location.

In automobiles, front axle assembly is a main load bearing member and houses steering linkages. Front axle assembly has two main parts namely axle beam and axle arm, interconnected by a kingpin. This kingpin allows the rotation of axle arm during steering events. To avoid metal to metal contact between axle arm and kingpin, bushes are housed on the top and bottom half of the axle arm & in axle beam. Due to radial load and steering rotation, as a weak member, bushes will wear out faster. This affects the proper functioning of steering mechanism. Hence, the bushes need to be evaluated prior to its implementation in vehicle. In general, bushes are evaluated using Pin-On-Disc test as a comparative study, but it does not simulate exact boundary conditions as in vehicle. Next option is vehicle level validation but leads to more testing time and cost. Hence, as an optimized solution, the same vehicle operating conditions can be replicated in component level testing.

Based on customer application and loading condition, each Commercial Vehicle model has an entirely different usage pattern. To perform accurate durability validation, each vehicle model prototype should run on actual customer usage locations and loading conditions for the durability target kilometers. But it is time consuming and not practical. So a statistical approach is followed to generate the accelerated durability test sequence and target on in-house Proving Ground tracks to match the real customer usage for the durability target kilometers. Again a single durability test sequence and target cannot be followed for all vehicle models due to the variability in customer usage. For that, specific durability test sequence and target need to be established for every class of commercial vehicle. This paper summarizes the methodology to develop Durability test sequence and target for commercial vehicle based on the work carried out on variants of medium and heavy duty trucks.

In this work, durability of the bus structure is evaluated with a Virtual Test Model (VTM).Full vehicle Multi Body Dynamics (MBD) model of the bus is built, with inclusion of flexibility of the bus structure to capture structural modes. Component mode synthesis method is used for creation of flexible model for use in MBD. Load extraction is done by performing MBD analysis with measured wheel inputs. Modal Superposition Method (MSM) is employed in FE along with these extracted loads for calculation of modal transient dynamic stress response of the structure. e-N based fatigue life is estimated. The estimated fatigue life from the modal superposition method show good correlation with the physical test results done in 6-poster test rig.

Every class of commercial vehicle has an entirely different usage pattern based on customer application and needs. To perform accurate durability testing, these prototypes should run on real customer usage locations and loading conditions for the target life. However, this is time consuming and not practical, hence resulting in Proving Ground (PG) testing. It is also known that a standard PG durability cycle cannot be valid for every class of vehicle and every application. So a statistical approach was followed to develop an accelerated durability test cycle based on in-house PG test surfaces in order to match the real customer usage to the durability target life. This paper summarizes the methodology to develop Durability Validation test cycles for commercial vehicle based on the work carried out on a heavy duty tipper and an intermediate commercial vehicle.

This abstract work describes a method of data acquisition and validation procedure followed for a metal bumper used in commercial vehicle application. Covariance is considered as major phenomenon for repeatable measurements in proving ground data acquisition and it is to be maintained less than 0.05. In this project covariance of data acquisition is analyzed before physical simulation of acquired data. In addition to that, multiple testing conditions like uni-axial and bi-axial testing were carried out to attain the failure. PG data is used for bi-axial vibration test and conventional constant spectrum signal (CSD signal) is used for uni-axial vibration test. Target duration for uni-axial test (Z direction) was arrived using pseudo damage calculation. Strain gauges were installed in failure locations to compare PG data and rig data as well as to calculate strain life. Failures were simulated in bi-axial vibration test.

With increasing concern on energy security and energy efficiency, automobile industry has been conducting many research on technologies aimed at reducing weight and reducing fuel consumption thereby reducing carbon footprint of the vehicle without compromising safety, efficiency and operational ability. Alternative fuel vehicles such as Compressed Natural Gas (CNG), Liquefied Petroleum Gas (LPG), Hydrogen, Hydrogen-CNG (HCNG) blends and Liquefied Natural Gas (LNG) vehicles are some of the best solutions to minimize the dependence on fossil fuels which are depleting fast. Gas cylinders are the heavier portion of alternative fuel systems which adds more weight to vehicle unladen weight. In search of innovative materials for gas cylinders, composite materials have been the front runner in reducing weight of the vehicle, thereby reducing fuel consumption significantly.

In the present scenario, delivering the right product at the right time is very crucial in automotive sector to grab the competitive advantage. In the development stage, validation process devours most of the product development time. This paper focuses on reducing the validation time for damper (shock absorber) variants which is a vital component in commercial vehicle suspension system. New test facility is designed for both performance test and endurance testing of six samples simultaneously. In addition, it provides force trend monitoring during the validation which increases the efficiency of test with an enhanced control system. This new facility is also designed to provide side loading capability for individual dampers in addition to the conventional axial loading. The key parameter during validation is control of damper seal temperature within the range of 70-90°C. A cooling circuit is designed to provide an efficient temperature control by re-circulating cold water.

In the modern automotive sector, durability and reliability are the most common terms. Customers are expecting a highly reliable product but at low cost. Any product that fails within its useful life leads to customer dissatisfaction and affects the reputation of the OEM. To eradicate this, all automotive components undergo stringent validation protocol, either in proving ground or in lab. This paper details on developing an accelerated lab test methodology for steering gearbox bracket using fatigue damage and reliability correlation by simulating field failure. Initially, potential failure causes for steering gearbox bracket were analyzed. Road load data was then acquired at proving ground and customer site to evaluate the cumulative fatigue damage on the steering gearbox bracket. To simulate the field failure, lab test facility was developed, reproducing similar boundary conditions as in vehicle.