Research On Trajectory Planning And Optimization Of Robotic Excavator

In order to cope with the higher and higher construction requirements in excavating accuracy,labor intensity,work efficiency and other aspects,robotic excavators with independent excavating operation function has become the main trend of future development.Trajectory planning research is an important part to realize the autonomous excavating function of robotic excavators.However,problems such as low smoothness and large joint impact generally exist in the trajectory planning process of robotic excavators.Therefore,this dissertation conducts research on trajectory planning and optimization to address these issues.Firstly,according to the theory of robotics,the standard D-H coordinate system of the working device of the robotic excavator is established,and the forward and reverse kinematics of the system is analyzed,and the conversion relationship between the tip position of the bucket teeth and the Angle of each joint as well as the corresponding hydraulic cylinder expansion is obtained.The Monte Carlo method is used to complete the simulation analysis of the working space,and the excavating operation area is selected in the working space,the hierarchical decomposition idea is used to decompose the excavating area,and then according to the rules of path planning,and through the use of cubic spline curve interpolation method to complete the excavating path planning,the cycle path of a single excavating operation is obtained.Secondly,the connecting rod mechanism model of the robotic excavator was established through the Robotic Toolbox,and the trajectory planning was completed by piecewise polynomial 3-3-3-3-3,3-3-5-3-3,4-3-3-3-4,quintic non-uniform B-spline and quintuple polynomial fitting.The data obtained by different methods are compared and analyzed.The simulation results show that compared with other trajectory planning methods,quintic non-uniform B-spline curve method has more advantages in the smooth continuity of trajectory planning.Finally,the optimal objective function of time and impact synthesis is established,and the optimal solution of the objective function is obtained by sparrow search algorithm,and the quintic non-uniform B-spline curve is optimized,and the comparative analysis of simulation results is completed.The simulation results show that this method can not only ensure the working efficiency of the robotic excavator,but also reduce the impact borne by each joint,which plays an important role in realizing the autonomous excavating function of the robot.