Stewart Platform: how can i connect multiple joints to the same child link

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Hi,

I think my problem is similar to this post already posted in 2015 here is the link

I want to simulate a robot in Gazebo. This robot contains a kind of delta machine. It consists in :

• three cylinders,

• three conrods, linked with the pistons rods (tige_verin) on one side and with one plate (plate_camera_support) on the other side,

• a plate (plate_camera_support). My objective is to control the altitude and the orientation of the plate (plate_camera_support) around the X axis and Y axis.

Here is the tf_tree of my URDF model. But unfortunately, I’m not able to introduce the last 2 joints of the model (in red on the picture below). Is the last answer still relevant? Is there a trick to face this « problem » ?

PS: I’m working on Ubuntu 16.04 LTS and ROS Kinetic. Thanks in Advance