Study On The Workspace Of 3-DOF Delta Robot

Because of the advantages of large overall rigidity,large bearing capacity,small inertia,high speed and high accuracy,simple force control and low manufacturing cost,3-dof Delta parallel robot are widely used in the industry.The advantages are derived from it's structural features.But it is also because of its structural characteristics that its workspace is small and complex.The workspace of the robot determines the area that the robot can reach,and is one of the most important indexes of the robot design.Therefore,the paper studies the workspace simulation method of 3-dof Delta parallel robot deeply and analyzes its feasibility,quickness and accuracy.Further more,the relationship between the main structural parameters of robot and workspace is studied.These works are of great significance to the structural design of the Delta robot.Firstly,the kinematics analysis of 3-dof Delta parallel robot is carried out.On the basis of simplifying its structure,the calculation of the inverse position solution and the forward position solution is completed,and combined with the existing research on workspace of Delta parallel robot,three new workspace simulation methods are proposed.The main structural parameters of the 3-dof Delta parallel robot are analyzed and determined.The simulation results of three simulation methods are same when the main structural parameters are changed.This proves the feasibility of the three methods.Secondly,the results of three simulation methods are verified directly by measuring the real workspace of the laboratory Delta parallel robot.The results show that these three workspace simulation methods are correct.In this paper,three simulation methods are compared and analyzed in terms of time consuming and modeling accuracy.The results show that,from the point of view of rapidity and accuracy,the workspace simulation method based on forward-position method is relatively good among the three simulation methods.In the end,according to analysis method,the range of three main length structure parameters(35)r,,lL are determined and the relationship between three parameter changes and workspace volume and shape change is obtained.The relationship between the change ofactive rod input angle range and workspace shape change is studied by numerical method.In order to study the relationship between structure parameters and workspace more accurately,the solution of workspace volume and the maximum width of workspace in X,Y and Z direction under different active rod input angle range is proposed.The feasibility of the solution is proved by comparing the results with the analysis method.It lays a foundation for further research on the structural parameters of 3-dof Delta robot in a given workspace.