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A methodology is presented to do accelerated vibration durability test, on Electro Dynamic Shaker (EDS) by using Power Spectral Density (PSD) profile based on typical customer usage pattern. A generalized iterative procedure is developed to optimize input excitation PSD profile on EDS for simulating the exact customer usage conditions. The procedure minimizes the error between the target channels measured on road and the response channels measured on EDS. Also, response of accelerometers and strain gauges at multiple locations on the test component are arrived at based on a single input excitation using this procedure. The same is verified experimentally as well. Different parameters like strain, acceleration, etc. are simulated simultaneously. This methodology has enabled successful simulation of road conditions in lab, thereby arriving at a correlation between rig and road. The correlation obtained is based on the simulation of the same failure mode as that of the road on the rig.

The importance of style design has increased tremendously in Indian two-wheeler market and at the same time new styles become obsolete in a short period. This rapidly changing market trend demands simulation methodology to evaluate the component for various loads in the design stage itself to reduce the product development cycle time. Aluminum cast footrest is preferred for better looks compared to sheet metal or tubular footrest. Normal load carried by the footrest is quite low but consideration should be given for severe loads experienced by the footrest during adverse conditions, like for example, hitting against potholes at high speed. In this current work an initial design of a die-cast footrest bracket with a particular geometric configuration and material was analyzed using finite element analysis for static and dynamic loads.

In the recent years, reduction of new product development time is the major challenge for all auto manufacturers to sustain in the stiff competition. Durability evaluation is one of the most time consuming element in New Product Development (NPD) process. Finding a generic solution for commonly faced design issues is a key factor for dramatic reduction in evaluation time. Testing time reduction can be achieved by breaking down the evaluation into subsystem level and component level instead of complete vehicle. But the maximum time reduction can be achieved only through durability evaluation at material / process level. This type of evaluation yields a generic solution, which results in establishing all-purpose design and material selection criteria during initial stage of development. By adopting this technique, separate evaluation of vehicles/ subsystems for improvements in material, welding, process etc. can be avoided.

Fatigue life prediction is the most promising technique for drastic reduction of durability evaluation time, which is a critical element in the product development cycle. By using this technique, it is possible to reduce development time and cost, identify failure modes early in the development cycle, and design the component for optimum life. This paper discusses the optimisation of an important two-wheeler component namely, the center stand, using fatigue life prediction techniques. Also, it aims at establishing correlation among various customer usage patterns, accelerated endurance tests, and fatigue life prediction results using both experimental data and finite element (FE) models.

Automotive manufacturers today are faced with the challenge of producing high quality products in a short time. In such a competitive environment, higher reliability gives competitive edge to the manufacturers. However, higher reliability involves increased durability testing on their part, which leads to an increase in development time and cost. Therefore, it becomes imperative to re-look the existing test standards as against the actual customer usage conditions thereby optimizing the testing time and the development costs. With that goal in mind, this paper elaborates the procedure used for establishing a correlation between three structural durability test rigs and customer usage on the road. Two different approaches were adopted to arrive at a final correlation between the structural test rigs and the customer usage on the road. The first approach arrives at a one to one correlation based on the failure modes of different components observed on each of the test rigs and in field.

This paper aims at the estimation of dynamic wheel loads of a two-wheeler through mathematical modeling that will aid during the initial stages of product development. A half car model that represents a two-wheeler was used for this purpose. Road displacements were given as input to the model and the wheel loads estimated. Actual road data obtained from two-poster rig was used as input to the model thereby making it possible to calculate the wheel loads for different customer usage conditions on different roads. In this paper, a severe rough road was chosen for verification of the model with that of the rig as the rider dynamics on such roads are the most difficult to simulate even on the rigs. The estimated values from model were verified with those measured using a two-poster rig for the same road displacement. Attempt has been further made to establish a correlation between the ride comfort predictions from the model and the two-poster rig.