How to automate/schedule a Drobo Standby

I only really use the Drobo for nightly backups, so to conserve energy and reduce disk wear is there a way to schedule the drobos to go into standby after the backups complete (they take less than an hour).

the drobo’s do spin down their disks after 15 minutes of non use.

(i think for regular drobos you cant configure this - for the bigger / power powerful drobos you can manually set the time period)

is there an Applescript or something to unmount it from the Finder/Diskutility?

All Finder actions are available in Automator. For simple operations like you are looking for, you can just drag and drop in the Automator window and then set the schedule.