One type of UDE instance can be replaced with a UDE of another type. This is useful when different levels of detail are wanted. For example, when simulating a complete system, a simple representation of a given mechanism may be sufficient. But when studying the dynamics of the mechanism itself, a detailed model of that mechanism may be desired.
To be able to replace a UDE of this definition with a UDE of another definition, the new definition must at least have the same input parameters (i_reference_frame and j_reference_frame). If the UDE has output parameters, then these must also match.
The next step is then to define the two definitions as replaceable. Calling the following command does this:
ude modify definition &
definition_name = .MDI.linear_bearing &
isa = .MDI.nonlinear_bearing
This command in the above example will define the "linear bearing" definition as replaceable with the "nonlinear bearing" definition. Both definitions must exist when issuing this command.
If any parameters match between the two UDE definitions (for example, if radial_stiffness exists in both definitions) - the value of this parameter will be copied from the UDE of the old definition to the UDE of the new definition when doing the replace.