Some properties of the general n-trailer

If some of the trailers of the so-called n-trailer system are connected via a kingpin hitch, the kinematic model of the system is more complicated that in the standard case. However, something can still be said about the structural properties of the system, like controllability. The more complicated equations can be interpreted in terms of virtual steering wheels placed on the off-axle joints with steering angle which is a non-linear feedback from the original configuration state. Quite remarkably, the extra singularities of the system have an explanation in terms of these virtual steering wheels. This is also sufficient to assert that the general n-trailer problem can be embedded into the corresponding multisteering n-trailer system. The multi-chained form available for this last system can be recovered also for the general n-trailer if we replace the extra steering inputs with the aforementioned feedback loops.