Comparison of vibration reduction rates of agricultural tractors depending on suspension type

Background: Because of the tough conditions of agricultural tasks, agricultural tractor drivers can be exposed to extreme vibrations easily and continuously. The cabin suspension of a tractor can reduce the vibration effectively. However, in Korean market, the cabin suspension is not commonly implemented to the tractors yet. As a preliminary research for the development of a LSD-based front axle system with intelligent active suspension for 75-kW tractors, the vibration characteristics of three different tractors classified according to cabin suspension type were investigated.

Methods: PZT type accelerometers were used to measure the vibrations on the wheel axis and cabin while three different tractors were driven on a proving ground. Field experiments were conducted under different drive speed and road conditions. The test tractors selected were varied depending on cabin suspension type, such as a simple spring type, an adaptive suspension system, and no suspension. Because the masses and the tires of the tractors are not identical, a change in the vibration reduction rates of the cabins in a response to the input vibration on each of their wheel axes was compared as a performance index.

Results: The tractor with adaptive suspension showed the largest vibration reduction performance. Especially, the vibration around 5 Hz was considerably reduced compared to those obtained with the others. The tractor with suspension showed intermediate performance while the tractor without suspension showed the smallest reduction rate of the vibration.

Discussion: As expected, the cabin suspension largely affected the vibration characteristics of the tractor in terms of amplitude and frequency.

Conclusion: The results would be used as reference for the further study about active cabin suspension system of tractors.