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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.

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.

Vehicular Emission testing is gaining importance over the past years in the wake of requirements for real driving emissions with implementation of RDE packages across Europe / USA and various developing countries. Extending the same concept for other countries poses slight challenges in terms of geographical and climatic conditions prevailing in the country, where the climatic conditions are differing from Europe / USA. It is a challenge to accept the same boundary conditions as in Europe, at the same time the challenge is to find a threshold number in a more scientific manner. This study concentrates on determination and recommendation of thresholds for ambient temperature and altitude. The basis for temperature threshold would be to determine the percentage of time the temperature exceeded beyond the threshold over year in the country. The basis for Altitude is considered based on the percentage of total length of roads beyond the threshold altitude limit.

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 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 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.

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.

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.

Fuel economy is an important customer requirement which determines the position of earth-movers such as backhoe loaders in the market. Earth-movers are heavy duty machines that are used for construction works. Currently fuel consumption in earth-movers is quantified as fuel consumed per unit time (Liters per hour). Similarly, conventional measure of productivity of the earth-movers is in terms of volume of soil trenched per hour. Measurements using the above scales showed wide variations in measured fuel consumption and productivity, For the same equipment between measurements Two equipment of same make at different trench locations and Against the competitor equipment This inconsistency and lack of a proper measuring system made logical decision making extremely difficult. This paper describes the step by step procedures involved in deriving the methodology for robust fuel consumption measurement of earth-mover vehicles.

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.

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.

Ashok Leyland, India had commissioned a web portal towards serving their end customers with better fleet management. The services offered through this portal helps in improving the productivity and safety of vehicles, business operations and hence, the profitability of the customers. Track and trace, SMS/email alerts and report generation are the major functionalities of this portal. They assist the customers in analyzing the operations of their vehicles and take corrective actions towards optimizing them. However, there were certain problems faced by the customers, while accessing these functionalities through the web portal. This includes, significantly high lead time taken for report generation, unavailability of location details in the reports and track page due to early expiry of reverse geo-coding service limits.

Non air-conditioned buses constitute a major portion of public transportation facilities in many countries across the world. Inadequate cabin air circulation is a major cause of passenger discomfort in these buses. The aim of this study is to model the air flow pattern inside the passenger compartment of a bus and to establish the effect of solutions such as roof vents in improving the air circulation. RANS based CFD simulations with Shear Stress Transport (SST) turbulence model have been carried out using a commercial CFD solver. The CFD methodology has been verified by comparing results with experimentally validated LES simulation results available in literature. The vehicle model used in this study was the shell structure of a bus with an overall length of 7 m and a wheel base of 3.9 m. Simulations were carried out for a four vent configuration which showed an increase of 131% in the average in-cabin air velocity over the baseline model without any roof-vents.

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.