| Stacker mechanical arm is widely used in the field of production and manufacturing.High speed,high precision and high load-bearing ratio are the urgent application requirements of stacker mechanical arm.The servo level control system of industrial stacking manipulator has not considered the joint flexibility and link flexibility,so it is easy to have strong residual vibration in the start-stop stage.Aiming at the residual vibration caused by the flexibility factor of the stacking manipulator,systematic theoretical and experimental research was carried out from the aspects of the design and optimization of the stacking manipulator,dynamic modeling of the flexible transmission system and analysis of vibration characteristics,joint motion planning and input shaping method to suppress the residual vibration.The application scenario of industrial mechanical arm is complex and the servo level control system is encapsulated,which makes it difficult to develop and debug the dynamics algorithm.Therefore,a light stacker mechanical arm system is designed and built based on the structural characteristics of industrial mechanical arm.The size and shape of the main structure were designed,and the size of the boom was optimized based on genetic algorithm.Solidworks and Adams are used to simulate and select power components.Using Ansys topology to optimize the lightweight arm,the loadbearing ratio and operating efficiency of the arm are improved.The controller based on DSP is used to design and build a manipulator control system to facilitate the development and verification of various dynamic control algorithms.Each joint of the manipulator has a relatively independent transmission system.Starting from the joint space,the three flexible transmission systems of flexible joint rigid arm,rigid joint flexible arm and flexible joint flexible arm are modeled and studied respectively.Spong torsion spring model was used to describe the deformation of flexible joint,Euler-Bernoulli beam model was used to describe the deformation of flexible connecting rod,and dynamics models of rigid-flexible coupling transmission system of different categories were established based on Lagrange dynamics equations.The relationship between flexible parameters and residual vibration characteristics in different dynamics models was analyzed by Matlab simulation.The structural characteristics of different types of flexible systems are discussed from the perspective of transfer function,which provides a theoretical basis for the research of residual vibration suppression methods.Starting from the joint space,the motion trajectory between multi-path points in the stacking process is planned by using the cubic B-spline curve.Compared with the trapezoidal velocity planning method commonly used in industry,the acceleration and stiffness of the whole motion are smooth and continuous,which effectively inhibits the vibration and impact of the flexible system.Based on the input shaping technology,the convolution setting of the input signals of the flexible system was carried out.By eliminating the oscillating poles of the flexible system,typical ZV,EI and ZVD shapers were constructed,and the vibration suppression effect and parameter robustness were simulated and analyzed.The stochastic time delay(TO)shaper was used TO optimize the shaping time delay.Under the premise that the control signal does not overflow,better time delay reduction effect and robustness are obtained.The parameters of the servo system and residual vibration suppression experiments were carried out based on the lightweight stacking manipulator designed and constructed.The validity of quad B-spline joint motion planning and input shaping for residual vibration suppression was verified in the motor torque mode and speed mode respectively.Experimental results show that the residual vibration amplitude can be reduced by more than 90% by the proposed vibration suppression method.There are 74 figures,14 tables and 118 references in this thesis. |
PDF Full Text Request