Analysis And Optimization Of Variable Amplitude Structure For GKZX22 Self- Propelled Aerial Work Platform

The aerial work platform is a mechanical device used to transport workers to a designated location.To meet the needs of different work positions,a luffing mechanism is required to change the working range.The luffing mechanism studied in this paper is a composite link mechanism consisting of a triangular mechanism driven by a variableamplitude hydraulic cylinder and two four-bar linkage mechanisms.Compared with the traditional three-hinge luffing mechanism,it satisfies the same working height of the whole vehicle.Under the premise,the boom length and the variable cylinder stroke can be reduced.However,the structure of the luffing mechanism is complicated.At present,the analogy is used to determine the position of each hinge of the luffing mechanism,and the influence of the hinge position on the force of the variable-speed cylinder and the stability of the working platform cannot be considered.In order to improve the design quality,it is important to carry out structural analysis and hinge position optimization for this luffing mechanism.In this paper,the composite connecting rod luffing mechanism of GKZX22 selfpropelled aerial work platform products is taken as the research object.Firstly,the mechanical analysis model of luffing mechanism is established.The minimum force of the variable amplitude cylinder is the objective function,and the position of the hinge is optimized based on the MATLAB optimization toolbox.The position of the hinge is optimized,and the force of the variable amplitude cylinder is reduced by 9.5%.Then the dynamic simulation is carried out for the optimized variable amplitude mechanism.The analysis results show that the motion stability of the optimized working platform meets the national standard design requirements.The 3D solid parametric finite element model of the luffing mechanism is established by using the APDL language of ANSYS software,and the typical working conditions are selected for analysis.By comparing the structural stress distribution before and after optimization,it is verified that the optimized luffing mechanism and the force of the boom are significantly improved.Finally,the stress test experiment was carried out on the luffing mechanism,and the experimental results were compared with the finite element analysis results.The structural design scheme identified in this paper has been adopted by the partner company and applied to actual product production.