Search Results

Gear rattle noise is a common issue in manual gear transmissions and is often difficult to resolve. This paper discusses a methodology involving development of a simulation model for noise prediction and subsequent design of experiments (DOE) analysis to select optimal design parameters to reduce rattle noise. A one-dimensional torsional vibration simulation model for a tractor driveline was developed and was correlated with experimental measurements. This correlated model was used to calculate the torque variation between the gear pairs based on engine excitations. The standard deviation of this mesh torque was used as a metric and was correlated to noise ratings assigned by experts during experimental evaluation. Using this metric as the response variable, a DOE was conducted to determine the contributing factors and their influence on the rattle noise. Optimal design parameters were selected to achieve target value on the rattle metric.

The design and analysis plays a major role for determining the root cause for the problem. Once the problem and its root cause were well defined, the solution for addressing the problem would be made clear. The engine excitation frequency and the chassis natural frequency were coming closer and it leads chassis to resonate. The resonance increases vibration levels at the Tractor footrest which was reducing comfort level of the operator. The vibration reduction methodologies like stiffening the structure, isolating the source from excitation and dampening techniques were studied to reduce vibration levels at footrest. The benchmarking evaluation was done with selected tractor models qualitatively to assess the difference in vibration level perception for customers. The test methodology and data acquisition methodology was formulated and used for better analysis and discussions.