Usage of QGraohicsItemAnimation

I have made an animation. below is the Image.

Attachment 5280

I have implemented animation on the plane shown in the image attached. But i am not able to get a smooth animation on this. But the animation is very jerky.

Can any help with QTimeLine and setPosAt function of QGraphicsItemAnimation?

How I can get smooth animation of qgraphicsitem whose parent is a qgraphicsitem using QGraphicsItemAnimation.

Thanks in advance.