Research And Implementation Of Super Large 6-DOF Load Platform System

The loading platform system must be able to output controllable six-component force in space in order to simulate large structures'complex load in actual working condition because of it suffering load from different direction. Stewart platform can realize six degrees of freedom in space movement, which also can output force and moment in three directions, is introduced into this loading fatigue-test system for large structures to realize the all-round live load simulation.This system adopts position control to achieve the purpose of force control in the paper, based on analysis of kinematics and dynamics on 6-dof parallel platform structure and the fact linear relationship between force and elastic distortion. The overall 6-dof platform mechanism design started after establishing semi-physical simulation model to verify that is right to satisfy the requirements of system loading force and moment, including: foundation structure, loading platform and connecting hinges, hydraulic servo system is designed to satisfy the requirements of system safety and controlling precision. Then control software is programmed after confirmation of system mechanical parts and hardware selection, adopting upper-lower two-level control mode. PC monitor interface developed on VC++ platform under windows operation system, completed human-computer interaction and the platform safety control; Lower computer adopts embedded Linux system, responsible for real-time control of platform. Whereafter, the dynamic response and follow effect of this platform is analyzed on the basis of safety. Checking platform mechanical parts and control system safety is the most important thing to do in system experiment analysis process. Finish loading platform and specimen docking principles and analysis before loading test specimen. Finally, simulation loading test on specimen is analyzed.The test result shows that this 6-DOF parallel force loading platform system has achieved the capability rated force 1000KN and rated motion 3500KMm. It has been taken into practice and could realize the all-round live simulation load, having a good simulation effect.