The Plane Front Wheel Manipulation Technology Research

The technology of airplane's nose wheel steering plays the key role in modern aircraft's ground steering, which is directly related to the safety of aircraft taking off and landing. In this paper, an advanced digital fly-by-wire control system of the nose wheel is designed to reconstruct a mechanical-hydraulic nose wheel steering system of a type of aircraft. The new nose wheel steering system has a simple structure, with high reliability, light weight, easy maintenance and important application value.The precision of the original front wheel steering system is low, the state transition time is uncertain, and the function of the shimmy dampening system is imperfect. In this paper, the solution of the scheme is presented, the component selection and design of hydraulic and electrical subsystems are accomplished.Airplane's nose wheel steering system has two functions by wheel steering and shimmy damping. The steering system is composed of the servo valve, actuator and mechanical drive system. The shimmy damping system is composed of the damping valve, actuator and mechanical drive system. With Simplifying the system, the mathematical model of the steering and shimmy dampening control are established.The simulation model of the nose wheel steering control system is established with AMESim software package, the dynamic process of servo steering is analyzed, which has good tracking and disturbance attenuation; the simulation model of the shimmy dampening system is established, the impact of various parameters on the characters of the shimmy dampening function is analyzed; the simulation model of the switch state of the system is established, which simulates the rapid unloading valve of hydraulic subsystem in the switching process, the results show that the conversion process is quickly, which solves the existing problem of uncertainty of conversion time.The experiment of the digital fly-by-wire control system is completed in the self-built platform. The results show that the new digital fly-by-wire nose wheel steering system meets the design requirements.