Dynamic simulation system of space robot with series rotary joint

The kinematical and dynamic models of space robot are more complex than fixed-base robot on ground because the free-floating base increases the system's degrees of freedom, and the space robot in low orbit was significantly affected by Gravity Gradient Torque. Firstly, the dynamic equations were derived based on the Lagrange equation. Then the coupling dynamics was deduced with the Newton-Euler Equation. The numerical computing method of the nonlinear part of the dynamic equations was introduced in detail, and the gravity gradient torque of the space robot was derived at the same time. Finally, the modularized space robot simulation system with rotary joints in series was established with these equations, and the influence of the gravity gradient torque was given by the simulation. Suggestions for decreasing the influence were presented as well.