| In order to prevent the instability of the empty roof in the comprehensive roadway,the hydraulic advanced support is usually used to temporarily support the roof.Two sets of support groups of the supporting equipment are rigidly connected by double hydraulic shifting cylinders in order to ensure that the supporting equipment can realize autonomous alternating steps in a complicated roadway environment.However,due to the fact that the actual hydraulic system generally has the characteristic of the dead zone of the valve,the time-varying characteristics such as the drift of the oil temperature,and the uncertainty of the friction at the hinge of the transverse beam,it is difficult to maintain the displacement synchronization of the double cylinders,which directly affects the forward displacement accuracy of and the efficiency of the support.For this reason,controlling the displacement of the double shifting cylinders and ensuring the displacement synchronization is the key to improving the displacement quality and efficiency of the support.In addition,related research shows that the configuration characteristics of hydraulic pipelines have an important impact on hydraulic systems and even dual-cylinder synchronization systems.Therefore,how to effectively weaken the influence of the pipeline configuration difference on the dual-cylinder synchronization system is also the key problem of improving the synchronization performance for the dual-cylinder synchronization system.Aiming at the problem of synchronization control of the shifting cylinder without considering the pipeline configuration,a dual-cylinder synchronization control method based on fuzzy self-tuning PID is proposed.Firstly,the advantages and disadvantages of the control structure and control strategy of the commonly used electro-hydraulic servo system are compared and analyzed.Then,a shifting cylinder Synchronization control method based on fuzzy self-tuning PID is proposed combined with the advantages of fuzzy control and classical PID control according to the characteristics of the existing control method.Finally,the simulation results show the effectiveness of the proposed control method based on the joint simulation platform of AMESim and Matlab.Synchronous-decoupled adaptive sliding mode control method for dual-cylinder with different pipelines is proposed for the situation of valve-controlled dual-cylinder synchronization control problem considering the difference of pipeline configuration.Firstly,the dynamic characteristics of the hydraulic pipeline are modeled and analyzed based on the previous part,and the mathematical model of the dual-cylinder synchronization system considering the pipeline configuration is established.Secondly,the decoupling method of the compensation is used to decouple the mathematical model of the system based on the coupling characteristics existing in the system.Then,the adaptive sliding mode variable structure control strategy of hydraulic cylinder displacement is proposed due to the fact that there are still unmodeled and uncertain factors for the decoupled subchannel model.Finally,the experiments under different working conditions verify the necessity of pipeline research and the effectiveness of the proposed control strategy based on the joint simulation platform of AMESim and Matlab,which lays a theoretical foundation for the robotization and unmannedization of the hydraulic advanced support. |
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