Simscape does not solve when I include a rotational friction block.

I am trying to model the stiction in a DC motor actuated stystem, but when I include the rotational friction block in series with the motor torque output the ssytem is no longer able to solve.

The error is message is:

• Transient initialization at time 8.150248430603002, solving for consistent states and modes, failed to converge.
• Nonlinear solver: failed to converge, residual norm too large.

When I comment through the friction block, the model works as expected. Any idea why the addition of this block would cause such issues?

I am fairly new at Simscape and Simscape Electrical, so it is very possible that it is incorrect syntax on my part, but I'm not sure how it should be setup.

Answer 1

[Sabin]

The Rotational Friction block represents the friction in the contact between rotating bodies. The correct way to connect this block to the DC Motor is by connecting the Motor and Friction R ports and the Motor and Friction C ports (see attached image). I hope this helps.