Mechanical design and motion analysis of a small intelligent inspection robot for nuclear power plant

Since Fukushima nuclear accident, international society is paying more and more attention on the safety of nuclear power. The healthy monitoring is the most important means for earth warning. In this paper, we designed a small intelligent inspection robotic system for application in nuclear power plant. First, we analyzed the monitoring requirement for key nuclear power devices, and determined the function, composition and technical specifications of the robot. Second, a 5-DOFs serial mechanism with two suction feet was designed. It has a symmetrical structure. The five revolute joints are arranged in the configuration of Roll-Pitch-Pitch-Pitch-Roll (abbreviated as RPPPR structure). And then, the analytical inverse kinematics equations of the robot were derived. For a given pose of one end with respect to the other end, there are four solutions of the joint angles. The users can determine the most appropriate solution according to the current configuration and other constraints. Finally, the dynamic model based on ADAMS software was created and the simulation study on typical cases was performed. The simulation results verified the mechanical design of the robotic system.