Below is one option for accessing the generator from the model. With this you can just include the :url_name
or whatever you want to call it, in your form for making the object. In my case it is set up so if a string is not entered it sets the url_name to something else.
Class Foo < ActiveRecord::Base
has_friendly_id :url_name, :use_slug => true, :approximate_ascii => true
attr_accessible :url_name
def url_name
read_attribute(:url_name) || "some other default"
end
end
Also, this is a little older but for more information on FriendlyID checkout this railscast