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Two-poster rig plays a very important role in accelerated durability evaluation in a motorcycle industry, similar to what a four-poster rig does in a car industry. The rig simulates the exact road conditions in the vertical direction through tire coupling by applying feedback control on displacement. On account of its ability to simulate to the exact customer usage conditions, it reproduces the failures realistically as it happens on the field. However, as complete vehicle is required for testing on the rig, the testing happens mostly in the advanced stages of product development. Any failures beyond the concept stage have a huge impact on the development time and cost and the same should be avoided. Therefore, in this paper, a virtual testing methodology is proposed, based on which potential failures on the vehicles can be captured at the concept design stage itself. An ADAMS model of a motorcycle was created.

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.

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.

Two wheelers are very popular as means of transportation in ASIA. It is also used as load carrier in some places. Chassis frame is a very critical part of a two wheeler taking most of the loads coming from the roads. During the design and development stage, structural integrity of the frame needs to be established. Bump test is one of the critical life tests performed on the vehicle for evaluating the fatigue life of the frame. Normally, three to four iterations take place before frame passes this bump test. This is a time taking test process (1week per iteration) and does not guarantee the end result. In the new approach, the bump test simulation is made using ADAMS software. The ADAMS model is validated by using the axle accelerations measured in the physical bump test. Subsequently, the loads obtained from ADAMS model are used in FEM software and the stresses are predicted. The stress pattern helped in identifying the critical areas.

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.