How to create parallel flexible mechanism

[AYPSY]

In your article, you have established the figure mechanism, a fixed platform and a moving platform, and the two platforms are connected by flexible rods. How to create the platform in the toolbox and how to control the connection point?

[AYPSY]

For example, if I want to connect three flexible rods and two platforms for the ball joints, how can I accurately set the ball joints according to my needs