Problem: the two-legged robot model displayed on the gazebo, click start, robot as if no support, robot fall on the ground

Guess: at the time of setting effort, the smaller the value fell faster, value, the robot will bounce, but can't find a fixed values for robot standing motionless,

Wanted to ask the bosses that is why,,,
(inertial data is generated in the solidworks, I in the generated urdf colonel for modification)