Weight Optimization of Off Highway Equipment Assembly

Weight reduction in construction equipment is sought to achieve energy conservation and also to comply with the vehicle safety and compliance regulations, managing the weight distribution across the rear and the front end of the equipment to achieve the optimum balancing. Of late the thrust on product weight has increased along with reduced time to market, leading to increased usage of structural optimization methods. This has been further supported by the availability of high performance computing at relatively low cost. VOC and CTQ tools provided the motivation and initial screening of the design variables. The structural optimization software provides an integrated platform for analysis as well as optimization of components. In this work, an optimization tool has been used for size and shape optimization of a construction equipment assembly and a commercial FEA package was used for verification and validation of the results. The overall purpose was to reduce the weight of an assembly through gauge optimization. For this purpose, structural weight was chosen as the objective function and structural responses such as stress was chosen as constraint. In addition to the global level optimization exercise, at the local level shape optimization was used to reduce peak stresses. In this case peak stress area was chosen as an objective function and the stress was reduced below the acceptable limit of the material, which was calculated by taking in to account the number of cycles of operation for each sub assembly. The main idea was utilizing factor of safety in optimization to make it a robust design. Significant reduction in design iterations as well as weight reduction was achieved by using the optimization framework