Design And Analysis On Cutter-Changing Robot Of Shield Machine

The cutter changing operations of shield machine are not only costly and time-consuming,but also with harsh environment.The operators have to face huge security risks.How to replace the cutters economically,and to ensure the safety of operators has become an important research.Developing Cutter-changing robots will be a good way and it will become a major progress in the maintenance of shield machine.The internal research of Cutter-changing robots is rarely,the reports abroad are also seldom.This paper focuses on the design and analysis of the Cutter-changing robot.The main works are as follows:(1)The design proposal of Cutter-changing robot system.The difficulties are summarized based on the structure of shield machine and the method of changing manually.Ideas are put forward:the coordinated operation between Cutter-changing arm and Deployment arm,a new installation method of cutters.Then the work-flow and work-area are also planned.The feasibility of Cutter-changing robot is proved theoretically.(2)The design of Cutter-changing arm for this robot system.The technical requirements are determined as well as the type,the DOFs,the drive and control methods,the materials referred to underwater arms.The mechanical structures of Cutter-changing arm are designed with SolidWorks into 3-D models.Then the driving force of actuators are estimated so as to design them.Finally,the function parameters are given.(3)The kinematic analysis of Cutter-changing arm.Kinematical equations and link coordinate system are established with D-H method.Relationships between cylinder stroke and joint angle are solved by mathematic models.Workspaces are solved with Monte Carlo method.Simulations are done with MATLAB Robotics Toolbox.(4)The Finite Element analysis and the optimization of Cutter-changing arm based on ANSYS Workbench.Static structural analysis is done in Workbench so as to check the strength and stiffness.The design shortages are identified and structure optimization is followed.The optimized arm can meet the design requirements very well.