harmonics in towing

[Garfield]

In older cars there was always a particular speed where there was a "drone" as engine vibration frequency matched the natural vibration frequency of part of the car, this is harmonics.

How many of us have experienced an outfit that is loaded correctly etc but is still for some reason unstable?

Every car and caravan has a natural rocking frequency, ie get hold of the towball or side of the caravan and push back and forth untill the car/van is rocking. If the rocking frequency of car and caravan are similar this could be a cause of unexplained problems.

This is just a theory but any comments????

 

[Lutz]

The short answer is yes, it is conceivable that this can contribute towards instability, but the subject is so scientific that without any data such as polar moments of intertia of car and caravan, lateral compliance of the suspension of both car and caravan, etc., it is rather difficult to comment further. It would make a good subject for PhD thesis at university.