Simulink VR rotation about center

I am facing a probelm in how to rotate a desk about itsef rather than about an external axis/point,

What i am getting is the desk rotating about itself and as the image shows below around some axis outside the center of mechanism not sure what it is,

I am applying a simple ramp signal input followed by VR signal expander to acheive the above motion,

I defined the centre and centre of rotation for all parts to be [0 0 0] and [0 0 0 0] respectively in the 3D world editor,

What can the problem be?