Design And Analysis Of A Set Of Motorised Rack Extraction Mechanisms For An Antenna Vehicle

As a kind of mobile antenna carrier platform that can be set up anywhere at any time,the antenna vehicle has the characteristics of fast deployment and high mobility,which plays an important role in the modern military battlefield with strong mobile detection and survival capability.At present,the antenna vehicle has been driven by hydraulic power system,there are many problems such as technical instability and inconvenient maintenance;in recent years,the electric drive technology has made rapid development,which provides the conditions for the renewal and transformation of the antenna vehicle.This topic is based on the existing antenna vehicle technology,the antenna vehicle erection and retraction mechanism for electric transformation and innovative design,and the main unit mechanism to carry out systematic theoretical research.It provides theoretical foundation support for the technology upgrade of a class of antenna radar or rocket launch mobile carrier platform.The main research contents are as follows:Firstly,based on the spreading ratio and space requirement of the antenna vehicle support legs,a new type of support leg spreading mechanism based on a parallel four-bar mechanism in tandem with an unloading mechanism is proposed.The kinematic study and simulation analysis of the mechanism are completed;the rack and pinion drive scheme and the low-profile crank slider drive unit scheme are proposed while keeping the main body configuration unchanged;the kinematic derivation and simulation analysis of the spreading and retracting scheme are carried out to obtain the displacement,velocity and acceleration variation laws of the centre of mass position of the support leg.Based on Newton’s Euler equation,the equation of force equilibrium for the spreading and retracting mechanism of the support leg of the antenna vehicle is established,and the binding force and restraining moment of each joint position of the mechanism and the driving force of the joint are obtained;the power selection of the parallel four-bar spreading and retracting mechanism,the rack and pinion driving mechanism and the low-profile crank slider driving mechanism is completed;the simulation of the spreading and retracting motion based on Adams is completed,and the variation law of the binding force,restraining moment and driving force of the rotating joint of the mechanism is obtained;the simulation of the static mechanics of the key components is verified by ANSYS.Under the condition that the layout of the double-lifting mechanism of the antenna lifting system and the performance requirements remain unchanged,a replacement scheme for the electric cylinder unit of the roller screw chain extension mechanism is proposed,which effectively solves the problems of large load capacity,long stroke,and rapid extension and retraction;the kinematic analysis of the roller screw chain extension cylinder mechanism is completed,and the relationship between the telescopic distance of the electric cylinder and the rotation angle of the antenna is obtained;based on the ANSYS finite element simulation software,the stiffness simulation and strength check of the key components of the system are carried out.Finally,a solution is proposed for an electrically driven multi-clutch mechanism,using cross couplings to compensate for misalignment in the long-distance clutch;drive force calculation and selection,strength and stiffness checks are completed.