基于时变引导向量场的阀口独立液压挖掘机路径跟踪控制OA

It is difficult for hydraulic excavators to achieve high-precision path tracking in complex dy-namic environments,a hierarchical control architecture was proposed based on time-varying GVF.Firstly,the normalized time-varying guidance vector field was constructed as the upper planner,and the conver-gence term was designed based on the Euclidean distance function to drive the system to converge to the pa-rameterized target path globally.Then a dynamic feedforward compensation term was introduced,and the null space projection mechanism was used to eliminate the influences of time-varying path geometric defor-mation on the tracking performance of the manipulator,so as to ensure the dynamic tracking ability to the target path.In addition,the ultimate boundedness of the system under model uncertainty and external dis-turbance was proved by Lyapunov stability theory,and the quantitative relationship between disturbance in-tensity and tip trajectory deviation was derived.Furthermore,a singularity avoidance mechanism was pro-posed to ensure the uniqueness and continuity of the global workspace solution of the vector field corre-sponding to the tip trajectory of the excavators.For the independent hydraulic system of the valve port,the lower controller designed a coordinated control strategy of oil inlet flow and oil return pressure to achieve high-precision tracking of the output commands of the planner and improve the energy efficiency of the sys-tems.Finally,the effectiveness of the algorithm was verified by simulation.