Timed Locking Mechanism

Looking for an experienced engineer to design a simple locking mechanism for a lab project. Need a locking, timer controlled, rotating cap for larger sized test tubes/conicals. Functionality needs to be: A nonremovable, fixed cap for aforementioned test tube that is unidirectional, and is unlocked (cap now able to be freely rotated) when a preset timer hits zero. When the cap is rotated 270 degrees, a trigger is hit that resets the timer and relocks the rotating mechanism. In essence, a rotating cap that is nonrotatable when locked, unlocked by a timer hitting zero after when it can be rotated, and then a trigger is hit when 270 degrees rotation is reached at which point rotation is locked and timer resets; process then repeats (using a preset timer). Example of size needed: [login to view URL] Need the cap to be like the one in example link, but does not need to be removable. Only unidirectional and locking based on timer. Need a single physical sample of the built apparatus and all engineering plans to recreate multiple of the mechanism for proprietary lab research project. Contact for more details and specifics.