Estimation of Load acting on a Crane Hook by Inverse Finite Element Method

Machines and structures are designed and developed for carrying out certain tasks. Further improvement in quality and performance of the product is possible with design refinement. Finite Element analysis is a technique used for obtaining the stress distribution due to loads applied on the member. The forward finite element analysis is based on some estimated loads. However, the loads actually acting on the machines and structures are unknown. Analysis based on estimated or predicted load has only limited application. The inverse finite element method is a hybrid, experimental and numerical technique for the processing of measurement data taken on existing members who will help us in determining the operating loads. In this paper, inverse finite element technique is employed for estimating the load acting on a mechanical member. A fundamental experimental work has been carried out on crane hook. A crane hook having trapezoidal cross-sectional area is used for analysis. The forward FE analysis is carried out in Ansys. The nodal strain at required positions is recorded. The strain measurements are used in conjunction with the results of finite element analysis to predict the applied load. The magnitude of the load estimated by this method is within 2% of the actual applied load. This demonstrates the advantages of the inverse FEM method for predicting the load.