Research On Motion Stability Of Drive-module Of Four-wheel Independent-steering AGV

As the intelligent equipment of automatic storage system and flexible production system,AGV(Automated Guided Vehicle)is the key link between production and transportation,which can realize the visualization of production process and maximize production efficiency.The research of a four-wheel independent-steering AGV that can realize natural navigation,frequent movement,and precise location is of great significance to improve the intelligent and flexible level of the workshop.Motion stability is the most basic dynamic characteristic of AGV.As the drive module is the foundation of AGV motion,it is very necessary to study its motion stability.This paper takes the drive module of four-wheel independent-steering AGV with the laser radar navigation as the research object,and explores its influence on the motion stability performance of the AGV from the aspects of model designing,rigid-flexible coupling simulation,experimental comparison,control parameter optimization based on fuzzy logic and structural optimization design.Firstly,according to the design requirements of the AGV and the factory environment,the modular design concept is used to design the drive module which consists of the three subsystems of the drive system,the steering system and the damping system.On the basis of the driving module,the AGV motion stability analysis model has been built.Secondly,in order to study the influence of the driving module on the motion stability of AGV,the dynamics simulation of AGV rigid body model and rigid-flexible coupling model has been completed under the simulated actual working conditions in the workshop,which proves that the flexible deformation of components has a significant impact on the calculation accuracy.On the basis of AGV experimental platform,the motion stability tests are carried out.By comparing the experimental curve and simulation curve,the motion stability analysis model is verified to be correct.Furthermore,the fuzzy adaptive PID controller is designed and the electromechanical co-simulation platform is built.By optimizing the damping control parameters,the motion stability of the AGV is significantly improved.Finally,according to the structural characteristics of the drive unit which have great influence on the motion stability,two innovative structures has been designed to improve the motion stability of AGV.The simulation comparison between the new and old models under the same working conditions certificates the new structures improve the motion stability.