Transmission line is an important channel for power transmission, multi-split transmission line is the main force of power transmission, and splicing tube is an important hardware on multi-split transmission line. The quality of its crimping and internal structure are hidden projects and directly affect power transmission. The normal and stable operation of the line, based on this, this paper proposes a robot mechanism configuration suitable for the flaw detection of multi-split transmission line connecting pipes, designs a virtual prototype model of the flaw detection detection robot, and carries out the flaw detection operation of the flaw detection device. Planning and establishment of the DH coordinate system of the flaw detection device, based on this, the kinematic equation of the flaw detection robot is deduced and its kinematic characteristics are analyzed. Finally, based on the established kinematic model, based on the Monte Carlo method in MATLAB software The robot toolbox ROBOT TOOLBOX was used in the simulation experiment, and the reachable space point cloud map of the end of the flaw detection robot in three spatial directions in the narrow space of the four-split wire was obtained by selecting the appropriate number of point clouds. At the same time, the robotic arm of the robot was built. Model, by setting reasonable motion parameters, the trajectory planning simulation results of the robot flaw detection and detection are obtained. The simulation results show that the robot end can achieve flaw detection without blind spots in the narrow working space formed by the four-split conductors. At the same time, the movement trajectory of the robot arm It is stable and smooth, and can realize the detection and detection of splicing pipes on multi-split conductors without collision and obstacle avoidance. The research in this paper has important theoretical significance and practical application for the system design and development of the splicing pipe flaw detection device for transmission lines and the intelligent operation and maintenance management of transmission grids.