Design,Analysis And Functional Verification Test On Nose Steering Control System For Large Civil Aircraft

Aircraft nose wheel manoeuver technology has played a dominant hand in ground manoeuver. Among them, nose wheel steering manoeuver system is a key proportion of landing gear design, its structure and performance have a prominent impact on ground taxi performance and control stability. Recently, along with the research and development of C919 airplane back in COMAC, domestic large civil aircraft has gained great progress. As a result, new requirements of steering mechanisms for larger steer angle and greater steer torque have been addressed. Research and analysis work on the topic of nose wheel steering systems is in urgent need. Nose wheel steering mechanism capable of larger steer angle is of great importance in domestic big plane research.This paper concentrates on dual actuator nose steering system and the nose wheel steering mechanism with rack-and-pinion and hydraulic control system, take C919 as an example, the dynamic model of nose wheel steering mechanism and mathematical model of hydraulic control system, the application of some of basic hydraulic control circuits in nose wheel steering control mechanisms has been analyzed. Based on previous research, two types of different nose wheel manoeuver hydraulic systems are designed. On basis of the result, hydraulic control systems of both dual actuator nose steering system and the nose wheel steering mechanism with rack-and-pinion are constructed in LMS Imagine.Lab and AMESim softwares. Then,dynamic model of nose langing gear with dual actuator nose steering system and the nose wheel steering mechanism with rack-and-pinion using LMS Virtual.Lab Motion software has been established. Co-simulations between such models and hydraulic control models of two types of steering systems are performed in AMEsim software and different steering performance under various cases has been analyzed.At last, the prototype has been constructed according to the design, and the functional verification test of the nose wheel steering system gas been performed based on the experiment requirements, and comparisons with the hydraulic simulations are made, which offers significant reference data for application of nose steering mechanism in big civil plane.