Effects of tyre inflation pressure and forward speed on vibration of an unsuspended tractor

•Reducing speed will be good method to reduce vibration of unsuspended tractor.•Reducing tyre pressure as low as will reduce vibration of unsuspended tractor.•Distribution proper moisture content of field can reduce tractor vibration.•Vibration of front axle higher than rear axle on every speeds and tyre pressure.•Vibration reduce significantly when front and rear tyre pressure reduced.

Relationships among intensity of vibrations, tractor speed, soil moisture content and tyre inflation pressure are important for the design of tractor suspension systems. This study was designed to evaluate the effect of tyre inflation pressure and forward speed on tractor vibration in the paddy fields of Southern China by using a two-wheel-drive unsuspended tractor with different combinations of forward speed, tyre inflation pressure and soil moisture content. During experiments, the vertical vibration accelerations in front and rear axles and triaxial vibration accelerations of the tractor body were measured using three accelerometers. Fourier analysis was applied to determine root mean square acceleration values in the low frequency range from 0.1 to 10 Hz. The results of the study indicate that tractor vibration is strongly affected by changing forward speed and tyre inflation pressure, and especially by changing forward speed and rear tyre inflation pressure. The research also shows the variation in the pattern of vibration intensity especially at the tractor’s front axle when field soil moisture content is changed.