| dc.description.abstract | This study aims to analyze the dynamic meshing characteristics of cylindrical gear pairs. Two cases were investigated: the dynamic simulation and experimental verification of a pair of spur gears with tooth tip relief and lead crowning modifications, and the dynamic simulation with improved design of a pair of helical gears with lead crowning and bias modifications.
For the spur gear case, a systematic simulation method for analyzing dynamic characteristic was proposed. First, a mathematical model of the cylindrical gear tooth surface with linear tip-relief and lead crowning modifications was derived based on the gear theory and differential geometry. Finite element analysis and KISSsoft software were used to conduct contact analysis under both no-load and loaded conditions, calculating static transmission errors, contact patterns, and mesh stiffness. Subsequently, a dynamic model of the spur gear system was established. The tooth contact analysis results obtained from the finite element analysis and KISSsoft were input into the dynamic equations to simulate the dynamic transmission errors under different loads and speeds. The root-mean-square (RMS) values were calculated and plotted, and the results obtained from both methods were compared.
For experimental verification, a series of dynamic experiments were conducted using a laboratory-built dynamic testing platform. Four accelerometers were mounted on the gears to capture vibration signals under various loads and speeds. After signal processing, the RMS values of experimental dynamic transmission errors were calculated to verify the accuracy of the simulation results. The actual dynamic performance of gear pairs can be pre-evaluated using the proposed simulation method.
In the study of the dynamic characteristics of helical gear pairs, an 8-degree-of-freedom dynamic model was first established, taking into account the influence of the helical angle. Furthermore, the dynamic simulation analysis process was automated and integrated with the optimization design methods. Both exhaustive search and genetic algorithm approaches were employed for optimization design and analysis. Exhaustive search was used to generate the contour maps of dynamic characteristics, illustrating the effects of lead crowning and bias modifications on the dynamic characteristics. Genetic algorithm was utilized to identify the combination of modification parameters that minimizes the RMS value of dynamic transmission error at operating speed. Finally, the improvements of the optimum design were evaluated, confirming the feasibility of the optimization design. | en_US |