I'm trying to set an initial angle position in the OM Inertia model using the phi.start parameter (see the picture https://photos.app.goo.gl/9prn9jZNuCWivdMR8).

If I enter a position of 2.31deg and I switch the selector to rad it change the value to -2.16421 rad.
I'd expect that the rad value should come from the simple formula 2.31deg * pi /180 = 0.040rad

Where this difference come from? Maybe a position reference?

Thanks