Patent 10119272 was granted and assigned to Amazon on November, 2018 by the United States Patent and Trademark Office.
A structure installed at a station can include an interference member held above a mobile drive unit area of the station. The interference member can be positioned to allow an inventory holder and a mobile drive unit to pass underneath. The interference member can also be positioned to contact a topside of the inventory holder to prevent the inventory holder from tipping into a worker area of the station that is adjacent to the mobile drive unit area.