Mine is exactly the same! I push him round the graveyard using the lumps and bumps near (very ancient) graves! This way I know exactly how long it will take to get him to sleep (5 mins) but on a path, more like 5 hours. At a street festival recently, when I knew he needed a nap, I had to go off and find a cobbled street, then it took 2 mins!!
DS was like this! He also settled best in our arms if we rested an elbow on one knee and bounced said knee up and down, fairly quickly! Much to mild consternation of a few friends/family who thought it constituted shaking him [hmmm]
This brought back memories of when I used to push DD back and forth over a placemat that I put on the carpet so it just bumped a tiny bit as I pushed her!! Smooth carpet never worked. Worked every time and I have passed on the tip to SIL for newborn nephew!!