Structural strength evaluation of driver's protective structures for self-propelled agricultural machines.

The high number of accidents due to rollovers of agricultural machines has increased the interest of researchers and organizations for standardization in this field. In the 1960s, standards to test rollover protective structures (ROPS) for tractors were designed and approved. Similar standards were introduced in the 1990s for earth-moving machinery, but ROPS standards were not defined for self-propelled agricultural machines. In the present work, the driver's protective structures of five different categories of self-propelled agricultural machines were analyzed with the goal of introducing ROPS with a strength level in accordance with the standards used for tractors while maintaining the same shape as the existing structure. The results show a low resistance level of the present structures on the machines selected for the tests. New structures that are able to sustain the loads specified by the tractor standard are not different in design from the existing structures, but an increase of the resistance of the materials or an increase of the thickness of the mountings is necessary.