Delivery dollies including biased locking assemblies for locking carousels

A method of controlling rotation of a carousel of a delivery dolly, the method comprising:

• rotatably mounting the carousel to a support column of the delivery dolly, the carousel including a recess on an underside of the carousel;
• mounting a locking mechanism to the support column, the locking mechanism being biased toward a locked position, the locking mechanism comprising a locking wheel on which the carousel rotates until the carousel reaches a preselected angular position;
• wherein the recess aligns with the locking wheel at the preselected angular position and, due to a bias force, the locking wheel extending into the recess thereby inhibiting rotation of the carousel until the carousel is spun manually, forcing the carousel to rotate and the locking wheel to retract until the locking wheel encounters the recess again.