[oop] Disable vmapping default (scalar) arguments

src/jaxsim/utils/oop.py

@@ -323,6 +323,12 @@ def fn_tf_vmap(*args, function_to_vmap: Callable, **kwargs):
                 case _:
                     raise ValueError(in_axes)
 
+            # Disable mapping of non-vectorized default arguments
+            for arg, value in argname_to_mapped_axis.items():
+                if value == sig.parameters[arg].default:
+                    logging.debug(f"Disabling vmapping of default argument '{arg}'")
+                    argname_to_mapped_axis[arg] = None
+
             # Build a dictionary (argument_name -> argument) for all mapped arguments.
             # Note that a mapped argument is an argument whose axis is not None and
             # is not a static jit argument.