Zero gravity simulation technique of five freedom docking test bed

The paper aimed to solve the weightless problem of the active docking ring (ADR) of a docking mechanism. The paper proposes a lift-on zero gravity simulation method with compact structure, which has an internal support rope for the active docking ring in the space docking process. The internal support structure ensures that the ADR rotates freely in three-axis direction. The intelligent fixed torque mechanism not only provides high precision balance force to gravitation, but also moves up and down with the ADR as well, realizing the motion of Y direction. The lateral motion (including X and Z directions ) of the ADR simply needs to overcome the friction torque of hinge by a swing link-double hinge mechanism resistance is small even in the top speed of the docking process due to the application of the longitudinal servocontrol mechanism. The paper gives relevant calculation and design data, and also some parameters experimental and balance simulation. The zero gravity simulation mechanism is installed in the internal walkway of a docking mechanism that could realize zero gravity simulation in the whole process of space docking. The respond time is 5 ms. The error of simulated weightlessness is about 1%-2% in each direction.