Wheel side load calculation using the strain measurement on swingarm and duty cycle development

Typically duty cycle development for any component carried out in the absence of direct acting load will be based on the measured strain from the Road Load data Acquisition(RLDA) and comparing it with the rig level testing. The biggest drawback from such an approach is the fact that the selected loads can be drastically different from the actual experienced peak load from the actual RLDA. This happens because the strain gauges will have sensitivity toward all three directional loads and sometimes due to complex structure design uni-directional sensitive locations are difficult to find out or strain gauge. This will lead to over predicting the loads in some cases and the selected load may end up yielding the component in a single cycle itself. This paper discusses the method employed to calculate the loads at the input load location using the strain gauges which are cross sensitive and using that input loads to select the loads for the testing of the component. Also it talks about the constraints it faces while trying to achieve the same and assumptions/considerations based on practical constraints to achieve the optimal results. Since it involves back calculating the input loads, this will help for the direct comparison based on loads and helps to improve the testing effectiveness to avoid anomalies in the results. Also this can be deployed for the various components and helps in improving the testing and simulation accuracy for improving the results in predicting the fatigue life and life expectancy of the components/vehicles.