Simscape end mass swings in the opposite direction

I have a crane model. In this model, when the crane starts compressing, the free mass at the end connected with a revolute joint is supposed to swing backwards, instead it swings in the forward direction. Can someone tell why this is happening?

Video link: https://drive.google.com/file/d/1-EjRv1avRLYaQ4FSAGPJTM-PEhSK0CDO/view?usp=sharing

Answer 1

[Steve Miller]

Without looking at the model directly, it is hard to say for sure.

Some possibilities:

1. The start of the motion is extremely abrupt, jerking the mass forward with a high acceleration and then slowing down to steady state speed. The crane is then actually slowing the mass down, causing it to swing forward.
2. The CG of the block is above the point where it is attached to the rod AND a rotational spring is holding it in it its current position.

--Steve

[Ranjit Roshan]

Thankyou, the problem was actually the first point, I had provided all the derivates till acceleration as inputs and the start of the motion was exteremely abrupt. So once I just changed it to follow a just distance setpoints, it started functional normally.