Remove the keyboard! No, but seriously, I was faced with this quite a long time ago. I never found a method around "allowing" the keyboard to be used. Except when the materials supervisor has me create a barcode with the user id and password, no HRI, and he did lock the keyboard in a tray. Btw, only he had the key! So, the pickers would scan the user id barcode, the password barcode, and away they would go.