For some reason I guess the business plan was about forgetting to get the permits...
Or even better to save all that faff, root a phone, run the drivers plate OCR software using the phones camera, stick to a gantry and send results via text message. You wouldn't even need live updates, pull the latest data at midnight each day.
Text is cheap.
Weatherproofing the camera and solar panels, getting permission to get them installed, actually installing them (working at heights over busy roads) and then maintaining them would be pretty expensive. You might also have to pay rent to whoever owns gantries, and what about locations where there aren't any existing gantries?
What about insurance in case you camera falls off the gantry onto a car and kills someone?
Edit: What about roads that don't have network coverage (not that uncommon in the Scottish Highlands)
