The self-checkin (SCI) module currently requires to set up a dedicated kiosk terminal for its purpose. The reason being that you can't provide user/password system preferences for an automatic login, like you can for the self-checkout (SCO) counterpart.
Our use case is the following: we are already using the SCO module with automatic login of the dedicated SCO patron, and our actual patrons identify themselves via their cardnumber. While they can obviously check in their books via the SCO module, we'd like to streamline the process such that they don't have to login with their cardnumber in order to simply return a book. The SCI module would be ideal for this but, effectively, it can't be used on the same terminal as switching between the modules currently requires a manual login of the dedicated SCI patron.
Related: going forward I think it would be useful to have a dedicated "Component" for the self checkin module as well (see the self checkout component).