In farm tractors, front end loaders are becoming popular attachments for primarily material handling such as loading, moving and unloading of woodchips, sand, gravels etc. It is also used for some severe load application such as tree uprooting and ripping operation which requires validation of loader frame and tractor as well. To validate the design, a standard pull-push test is carried out on tractor with loader in a laboratory. In this test front loader bucket is pushed against a rigidly clamped fixture with full engine throttle and maximum hydraulic cylinder pressure of loader. To avoid surprise failures during the test, a virtual simulation method needs to be developed and validated.
In this paper, a method has been proposed by authors for the above objective. A multi-body dynamics model of tractor with loader is created in MSC ADAMS and actual event is simulated using test loads & boundary conditions. Forces and moments are extracted on all tractor skid attachments points from MBD model. Afterwards, an inertia relief durability analysis is done in MSC Nastran using the extracted loads. Strain gauges are pasted on tractor front axle support, clutch housing and data acquisition activity is carried to extract strain level during test operation. The durability results are correlated with measured strain data and achieved more than 80% correlation.