Jackknife Condition for Backing up of a Vehicle Attached to a Long Wheelbase Dual Axle Trailers

The patent describes a controller and method for determining the jackknife condition of a vehicle-trailer system in a reverse drive maneuver. The controller receives operator-controlled vehicle steering angle and hitch angle measurements. It uses a mathematical model or a lookup table to determine the directional jackknife warning condition, which represents the angle at which the vehicle's steering cannot be reduced without increasing the angle between the vehicle and the trailer at the hitch. The controller also determines an absolute jackknife sufficiency condition, which represents the range of angles at which the steering angles cannot be found. The driver is then alerted if the hitch angle falls within either the directional jackknife warning condition or the absolute jackknife sufficiency condition. The technical effect of this invention is to improve safety and operational efficiency during reverse drive maneuvers by providing an alert to the driver when the steering angle cannot be reduced without increasing the angle between the vehicle and the trailer at the hitch.

The act of backing up a vehicle with an attached trailer can be a challenging maneuver even for individuals with considerable driving experience.

Such maneuvers often require counterintuitive inputs, making them error-prone, cumbersome, frustrating, and dangerous, especially for inexperienced drivers.

A common mistake when backing up a vehicle and trailer is to “jack knife” or “bind” the vehicle and trailer during the reverse motion.

When this occurs, the driver is prevented from being able to steer the vehicle and trailer any further along its desired path.

Backup maneuvers are particularly difficult with long wheelbase dual-axle trailers (as compared to single axle trailers), thus leaving the driver even more prone to jack knifing or binding.