It seems to me that hauling a trailer can be quite a chore for many people. Fortunately, I am not one of them. But for those that are, it seems like it would be easier to haul a trailer if the trailer had a steering system of its own.

This system would be much easier on a single axle trailer, but could also work on dual axles as well. Take something like the rear axle of a vehicle that has four wheel steering (some Dodge stealths and new Chevrolet/GMC trucks come to mind, I can't think of any others) or the front axle of an old, straight axle car (Pretty much standard on anything before the '50's or so), and use it or a trailer axle. Put some type of linear actuator on it, most likely electric, but hydraulic could work if equiped right). The wheels would turn in the opposite direction of the front wheels when the system is turned on (if not all of the time). This allows the trailer to better follow the truck's path when moving foward (to avoid taking out street signs on tight corners) and facilitate (sp? I don't care...) easier backing up. Would also use a stiffer hitching system since the trailer wouldn't have to rotate ariound the hitch near as much.

/ / front tires of car

| | rear tires of car

\ \ trailer tires

*note: not drawn to scale, and I didn't have time to draw a car hauling a trailer with a couple of jet ski's on it or anything. Please forgive me.

System would be computer controlled and could turn off for highway driving where this would be more dangerous than normal towing. Would potentially be used only on high end trailers sold mainly to people who have more dollars than sense and want to show off the newest toy on the block, but could also be produced in a simpler way to make it more affordable and adaptable for more general use..
-- Hunter79764, Aug 09 2006

Steerable Trailer Hitch Steerable_20Trailer_20Hitch
Here is my idea for basically the same problem. [BJS, Aug 09 2006]

Are you sure this would work as intended?
-- methinksnot, Aug 09 2006


me thinks not.
-- jhomrighaus, Aug 09 2006


Bone. If you set up the trailer and car correctly, you will have no problems with the trailer following in the tyre tracks of the car. I can't remember the correct geometry, but it's something like having the distance between the car's steer tyres and the hitch the same at the distance from the hitch to the trailer tyres. or something. I have my 4wd and trailer set up this way, and i can drive down very narrow tracks (fold mirrors back so they don't hit the trees) and the trailer, which is as wide as the vehicle, doesn't hit anything.

Secondly, this would be dangerously unstable. A heavy trailer "pulling" (slightly misaligned or steering off) will make the handling dynamics very difficult to control.
-- Custardguts, Aug 09 2006


Mechanically work, or not work as intended as in "It's a dumb idea"? I'm not offended if its the second one, I'm just not sure what you mean. The mechanical details would iron out with prototypes, and it should help in some way by swinging wider on turns and being able to manuver easier at slow speeds. It may not be worth the trouble to do, but in reality, neither are power mirrors, remote control car CD players, and just about every other convinience item on a car. Even if it help just a little bit, its more useful than rain sensing wipers.
-- Hunter79764, Aug 09 2006


I think its just bad all around. In general it not needed at any time. There is the very real threat of instability at high speed due to the required changes in steering geometry. I think the only place this could be safely used would be in slow manuvering and even then, there are very limited situations where it would help. In most cases I think it would just be in the way.

On the other hand, Many if not most inner city Hook and Ladder fire engines have steerable rear wheels in order to negotiate tight corners(due to extreme length), I think the more modern ones have a hydralic steering system, the older ones had a steering wheel in the back. So to a degree this is baked as well.
-- jhomrighaus, Aug 09 2006


The fire truck example is close to what I am picturing, but they only have 2 axles, right? So it is a 4 wheel steering system, obviously baked, I could be wrong though. And it seems to me that with proper alignment on the trailer axle, it would not be any more unstable than a 4 wheel sterring system. Maybe have a mechanical lock to hold the tires square at speed. The system probly would only be useful at slow speeds, as you said, but I think it would come in handy for recreational trailers more than industrial, as you might be picturing.

And I hadn't heard of that, [custard]. That seems like it makes sense. But it is hard to match the length of something like a small yaht trailer to the wheelbase of your Navigator/Escalade, making it difficult to park next to your $200,000 RV.
-- Hunter79764, Aug 09 2006


I like the idea. The only relatively large problem that comes to my mind, is that you would have to lose some cargo space to accommodate for the larger wheel wells necessary for the steering and suspension systems.
-- BJS, Aug 09 2006


No reason this wouldn't work; in fact, a lot of articulated trucks already have a similar system, as do many rigids. I wonder, though, whether activating the trailer steering should lock the towing hitch; it may be better. Also, the angle of rear steer should take into account the relative lengths of the tow car and the trailer.
-- angel, Aug 09 2006


I did a job interview for an engineering position at the company that makes the trailers for transporting the M1 tank. It had some sort of steering on the multiple trailer wheels, that struck me as incredibly overdone.
-- baconbrain, Aug 14 2006



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