Research On The Design And Analysis Of The Rack-and-pinion Nosewheel Steering Mechanism

At present, the nosewheel steering has become a main manner of aircraft ground steering, so thedesign of nosewheel steering mechanism is a key technology of the landing gear. With theimplementation and development of special programme about large civil aircraft in our country,launching the project of the nosewheel steering mechanism with rack-and-pinion which can meet thecivil aircraft’s demand—large turning moment and steering angle is of great significance. On one hand,it can contribute to the furtherance of our country’s marketability of large aircraft with proprietaryintellectual property rights; on the other hand, it makes sense to the large civil aircraft’s success ofChina.Based on the research object, the nosewheel steering mechanism with the rack-and-pinion ispreliminary designed. Then the ABAQUS software is applied to the typical part of themechanism—the rack-and-pinion doing finite element analysis which is compared with designparameters. The conclusion that the maximal contact stress comes to the gear surface near the endface can be validated by analyzing the results in the simulation process, as well as the consequencesmall deformation of the gear cause contact ratio higher than theoretical calculation. Later, the LMSVirtual.lab Motion software is applied to the whole aircraft model with the nosewheel steeringmechanism with the rack-and-pinion doing ground handling simulation analysis, and then thedynamic performance of rolling and steering of the aircraft is under research.At last, the method of choosing modification coefficient is got from the transmission of therack-and-pinion of steering mechanism. On the basis of the existing mature methods drawing sealcharts of the modification coefficient and transmitting features of the rack-and-pinion, the drawingequations of limit curves and quality index curves related to modification coefficient’s seal charts ofthe rack-and-pinion transmission are derivated, which provides one way and foundation foroptimizing this transmission.According to this paper’s research, some valuable experience and conclusion is provided for thedesign or analysis of the nosewheel steering mechanism with rack-and-pinion and lay a foundation forfurther optimization. It is of great instructive significance for the design of civil aircraft’s landing gearof our country.