Thank you for posting this. Nice experimental effort. All castors "chatter" at some frequency. I'd be interested if/how you managed to cure this with the length of the castor trail / wheel diameter or Balance / dampening the castor pivot etc. Best wishes, Steve
This is very much what I am designing. I have a Harbor Freight 48 x 40 utility trailer with a 20 cu ft car top carrier mounted on it. My problem is tha to turn, the cargo carrier has to be several feet back from the tail of the car, and I want it snugged up for aerodynamics.That means the trailer must swing with the car, and I need a swivel wheel at the back (or near the weight center of the trailer/cargo load). Why do you have only one side of the wheel supported? I have considered the rear swing arm of a motorcycle.