Keep On Truckin'

Keep ON Trucking (although you could argue here in the UK it should be Keep On HGVing or Keep On Lorrying!) is to continue or persist doing something - usually boring uninteresting or tedious. You can say it about yourself, to show that you plan to persist with the task, but keep on trucking is often said to encourage someone else who is doing a boring our unpleasant task.
Today was very much the former as we'd only headed out for a small walk down to the village and I had literally seen nothing blipworthy so I was having to encourage myself to keep going in the search for an image on such a grey and underwhelming day. It was only as we headed back home and I saw this truck based road sign peeking out between the structure of a nearby substation that I thought I had any kind of image - so at least you can say I persisted with the task!
For any roadsign nerds out there the sign is to indicate the zone exit for special goods vehicle waiting restrictions which apply to vehicles between 5 and 7.5 tonnes maximum gross weight. Not boring at all! :-)