Analysis of dual-gripper manipulators and finite element analysis of the flexible laminated hose for underground storage tank cleanup

The second generation long-reach manipulator - the dual-gripper Phase 3 Remote Tool Delivery (RTD) system has been developed to retrieve radioactive waste from underground storage tanks with internal structural members. The RTD is equipped with two grippers, one at each end of the system, to grasp the structural member. A vertical translation mechanism is also added to the system that enables the vertical motion inside the tank. This special feature provides greater dexterity and flexibility. Two operating open-chain configurations are considered and modeled. The first configuration is that gripper 1 grasps the structural member and gripper 2 is free to perform a designated task. The other configuration is that gripper 2 grasps the structural member and gripper 1 is free to move. The kinematics, dynamics and simulation of the system are emphasized. Finite Element Analysis (FEA) of the flexible laminated hose used to convey radioactive waste materials was investigated to learn about its structural behavior. The hose is considered relatively fixed at one end (the outlet) and subjected to different loading conditions at the inlet. Liquid (mixture of water and sludge) with high viscosity is sucked through the hose using a vacuum pressure. The software package employed for FEA is ANSYS 5.2. A total of 200 cases, with different X, Y and Z loading conditions at the inlet, for the hose under the consideration with or without vacuum pressure have been analyzed. Numerical results and the ANSYS graphic outputs provided for each case include the deformation, stress distribution and strain distribution throughout the hose