Research On Synchronous Control Method Of Double Joint Manipulator

With the introduction of intelligent technology and related disciplines,industrial manipulator have achieved rapid development.In order to meet the high-precision synchronization performance between the joints of the manipulator,not only the tracking accuracy of the single joint of the manipulator must be considered,but also the mutual cooperation between the joints must be ensured to jointly complete the production task.In view of the above problems,this thesis not only designs a single-joint position tracking controller to meet the tracking accuracy,but also studies the synchronization control to achieve highprecision synchronization performance.Therefore,it is of great significance and application value for the research on the double joint manipulator synchronization control method.In this thesis,the double joint manipulator is taken as the research object,and the position tracking method and synchronous control method of the double joint manipulator are studied.The main work of the thesis includes:(1)Firstly,the dynamic model of the manipulator system is obtained by analyzing the energy of the whole control system with Lagrange equation,and the Lyapunov stability theory is described.Secondly,the fractional calculus theory and sliding mode control theory are introduced,which lays the theoretical foundation for the following.(2)Aiming at the single-joint position tracking control of the manipulator,firstly,the fractional sliding mode approach law is studied,and a fractional sliding mode control method is proposed to study the single-joint tracking control of the manipulator,based on the combination of fractional calculus and sliding mode control theory,two controllers of fractional sliding mode approach law and fractional sliding mode surface are designed.Then the classic double joint manipulator is used as the control object to simulate and verify the proposed method.The results show that the designed controller has the characteristics of fast tracking speed,markedly improved chattering and strong anti-disturbance capability.(3)On the basis of determining the single joint position tracking control,aiming at the problem of the cumulative effect of synchronization error caused by the chain control,the virtual principal axis was first introduced to study the PD virtual principal axis cross-coupling control method.In order to meet the higher synchronization accuracy of the control system,a fractional sliding mode controller was introduced into the cross-coupling control to complete the double joint manipulator synchronization control.Later,the control method was improved,and a cross-coupling control method of variance virtual principal axis based on fractional sliding mode is proposed.Finally,the simulation comparison verification is performed.The results show that the control method proposed in this thesis can effectively eliminate the cumulative synchronization error between the double joints and weaken the chattering.At the same time,the angular displacement adjustment time of the joints and the root mean square error of the synchronization error are greatly reduced,which further improves the synchronization accuracy of the manipulator joints.