I came across a need today to allow a regular (non-root) user to mount disksĀ in Ubuntu 14.04 Trusty Tahr. I usually use sudo but in this case I needed to be able to run photorec as a regular user.
The way to accomplish this is to add the regular user to the disk group. To accomplish this, run this command:
sudo usermod -a -G disk <username>
If you are logged in as that user, you will have to log out and log back in to receive the permissions. Once this is done you should be able to mount disks without using sudo or being root.