Jixie chuandong (Jun 2021)
Dynamic Reliability Analysis of Flying Car Gear Transmission System
Abstract
As a new type of transportation for future urban air transportation，flying cars are intelligent，efficient and convenient. As a key component of the power transmission of a flying car，the safety and reliability of gear transmission has become a difficult problem restricting the development of flying cars. However，the current reliability analysis method for the gear transmission system of flying cars is lacking. The existing design method fails to consider the influence of the strength degradation and failure correlation on the reliability of the transmission system which has a potential failure risk. Therefore，a dynamic reliability analysis model of a flying car gear transmission system considering the correlation between strength degradation and failure is established based on the theory of stress-strength interference. According to the flight mission profile，the load spectrum is established and the gear contact and bending stress are obtained. The complex stress history is equivalent to symmetric cyclic stress by Goodman criterion，which matched the fatigue damage calculation based on S-N curve. A gear strength degradation model is established based on the theory of non-linear fatigue cumulative damage，and the Copula function is used to describe the failure coupling correlation in the transmission system. Combined with the stress-strength interference theory，the reliability evolution law of the flying car gear transmission system is expounded，which lays a foundation for the dynamic design and reliability optimization of the gear transmission system of flying car.
