Design Of 4-DOF Heavy-duty Casting Robots

Casting robots are not only used in die casting,precision casting,casting handling and transmission,but also can be used in molding,core making,core cutting,pouring,cleaning and inspection and other processes,greatly saving labor,improving casting production efficiency,manufacturing accuracy and quality,and realizing mechanization and automation of casting production.However,the existing heavy-duty casting robots mostly adopt tandem robotic arm structure,especially the pouring operation robot,due to the relatively harsh environment of the production workshop,the large operating load,the fixed robot station,production efficiency and product quality need to be improved.In view of the above problems,this paper designs a four-degree-of-freedom heavy-duty casting robot that can realize autonomous navigation,which not only improves the load capacity of the casting robot,but also improves the quality and production efficiency of products,and at the same time,can realize unmanned production in the process of pouring operation.First of all,based on the TRIZ theory innovation method,nine-screen method,functional analysis method,causal axis analysis method and other methods are used to analyze the current casting robot system,and the contradictory matrix,matter-field model and other methods are combined with the innovation and invention principle and standard solution to optimize the innovative design.After the feasibility analysis of the design scheme,two overall design schemes of heavy duty casting robot with four degrees of freedom are selected.In view of the high load demand in casting production,the strength analysis of the key parts of the two schemes is carried out,and the optimal scheme is finally determined.In order to realize the autonomous pouring of heavy duty casting robot with four degrees of freedom,the path planning of the robot was carried out.In view of the shortcomings of the traditional A* algorithm,the traditional A* algorithm is improved based on the method of optimizing node selection and limiting distance.The improved algorithm solves the problems of A large number of redundant nodes and the contact between path and obstacle vertex in the traditional A* algorithm.For the problem that A*algorithm cannot realize the robot avoiding dynamic obstacles,the dynamic window algorithm in local path planning is adopted.The dynamic window algorithm has a boundary in the sampling velocity space during the planning process,and it will fall into local optimization and fail to reach the end point.In this paper,the key nodes in the results of the improved A* algorithm are taken as the piecewise target points in the dynamic window algorithm,and the two algorithms are fused.The fusion algorithm solves the problem that the path of the A* algorithm has a large number of redundant points and cannot avoid dynamic obstacles,and also solves the problem of local optimal path in the dynamic window algorithm.Multiple groups of comparative simulation experiments were carried out on the MATLAB platform,respectively in the simple static obstacle environment,complex static obstacle environment and dynamic obstacle environment.The simulation results verified the effectiveness of the fusion algorithm,and also verified the feasibility of the fusion algorithm applied to the heavy casting robot.a path planning experiment based on mobile robot in ROS system is carried out to further verify the feasibility of fusion algorithm.As the key component of the heavy-duty casting robot,the running trajectory of the pouring actuator directly affects the motion stability and pouring quality of the pouring ladle.In order to ensure the smooth operation of the pouring of the pouring of the heavyduty casting robot,avoid vibration and improve the quality of the castings,a composite polynomial based on the five-degree polynomial and sinusoidal acceleration motion law synthesis of the pouring process trajectory planning method of heavy-duty casting robot is proposed,and the motion trajectory of the pouring package in the pouring operation is simulated by ADAMS,and the simulation results verify the feasibility of the proposed trajectory synthesis method and the accuracy of the theoretical parameters obtained by kinematic analysis.Figure [41] Table [8] Reference [76]...