How to collect a form user's name anonymously?

Hi all.

I want to send a survey form using Smartsheet to a group of users. I want to be able to collect the user's name on the backend (if possible) without the user knowing I'm collecting their name. It's basically so the user will be truthful in their survey responses AND only I would know who said what. Is there a way to do this anonymously?

Thanks, SB