fare gate
Lock fare gates, also called a baffle gate or a swing gate, are types of gates that allow one person through at a time to enforce one-way traffic of people. Some gates require paid access in order to pass through. They may have integrated ticket machines to give one their ticket, or use optical interfaces where one can check in with a chipped card.
Types of fare gates include turnstile (tagged on Danbooru only when depicted as rotating tripod turnstiles), drop arm, full panel, flap barrier, bi-parting, swinging, retracting/sliding, etc.