Low-speed maneuverability enhancement for long single-unit vehicles

A steering assembly for an elongated single-unit vehicle having a frame with front and rear portions, said rear axle coupled to the rear portion of the frame, and rear wheel assemblies connected to the rear axle and adapted to engage the ground, comprising:

• a front steering axle connected to the front portion of the frame and connected to steerable front wheel assemblies that are adapted to engage the ground;
• means for steering said front wheel assemblies through a first range of angles;
• an auxiliary steering axle connected to the front portion of the frame rearward of said front steering axle, and connected to steerable auxiliary wheel assemblies that engage the ground, said auxiliary wheel assemblies being coupled to said front wheel assemblies and being adapted to be steered through a second range of angles, wherein a ratio between said first range of angles and said second range of angles is a steering ratio;
• and
• means for remotely adjusting said steering ratio coupled to said auxiliary wheel assemblies.

A method of steering a motor vehicle around a corner, the motor vehicle having a frame, a front steering axle with steerable front wheel assemblies attached thereto and adapted to turn through a first range of angles, at least one rear axle with rear wheel assemblies connected thereto, an auxiliary steering axle connected to the frame between the front steering axle and the rear axle, the auxiliary steering axle having steerable auxiliary wheel assemblies connected thereto and adapted to turn through a second range of angles such that a ratio between the first and second range of angles is a steering ratio, and a vehicle steering system coupled to the front and auxiliary steering axles, the method comprising the steps of:

• moving the vehicle along a path having a curve such that the vehicle has a first steering ratio;
• lifting the front steering axle from a lowered position, wherein the front wheel assemblies engage the ground, to a lifted position, wherein the front wheel assemblies are lifted off the ground while the auxiliary and rear wheel assemblies remain in engagement with the ground, thereby shortening the wheel base of the vehicle prior to entering the corner;
• adjusting the second range of angles through which the auxiliary wheel assemblies turn so that the vehicle has a second steering ratio different front said first steering ratio;
• and
• steering the vehicle around the curve such that the auxiliary and rear wheel assemblies are operable to move along the path.