Frequency roll response of farm tractors’ cabs

The increase in the use of the tractor as a transport vehicle has emphasised the containment problem of the vibration transmitted to the driver. The rolling movement at a low frequency increases the transversal acceleration and influences the global vibrations’ level transmitted to the driver. Recent works have demonstrated the capability of ISO standards, used for handling tests in the automotive sectors, to analyse and characterise the dynamic behaviour of tractors. The frequency sweep test was used to analyse the frequency response of the cab’s rolling movement, which in turn was compared with that measured on the tractor’s driveline. The aim was to evaluate the capability of the suspension system to isolate the cab from the roll oscillations coming from the driveline. The results show a high amplification of the roll from the driveline to the cab, in particular, in the condition with implements connected to the three point linkage.