Application of Power Spectral Density to Recognise the Important Factors Creating Tractor-Subsoiler Vibrations

A deep working oscillatory subsoiler was developed at the University of South Australia to be towed by a tractor (3 t and 70 kW) in a semi-mounted configuration. During use, the soil-tool interaction forces transferred too much vibration to the tractor when operating at the desired subsoiler settings. In order to reduce the tractor vibrations, the source of vibration was studied using the power spectral density method to correlate the tractor seat vibrations to machine operating parameters. It was found that tyre lug engagement and the engine speed did not have significant effect on tractor vibration. The soil-tool interaction of both soil cutting and compaction during the oscillating motion of the tine, combined with the torque peaks on the driveline from the power take-off to the tines, had the dominant effect on vibration.