6
TEBS E
GIO functions
82
6.9
Dynamic wheelbase control
6.9.1 Manoeuvering assistance (OptiTurn
TM
)
Vehicle type
Semitrailers with 2 or 3 axles, rear axle as a tag axle or lifting axle.
Central axle trailer
Purpose
Increasing manoeuvrability.
Can be used as an alternative to a trailing steering axle.
Function
OptiTurn is able to detect tight curves from the differing wheel speeds and corre-
spondingly unloads the rear axle according to the specifications of the traction help
system. This causes the fulcrum of the axle unit to ‘migrate’ from the central axle
between the two loaded axles remaining on the ground and reduces the turning
circle and improves the manoeuvrability of the whole vehicle.
The relief of the third axle can be defined by means of the parameter settings. This
prevents overloading the other axles on the trailer.
Benefit
• Reduced tire wear in tight curves.
• Can save steering axle and steering axle control.
• Improves manoeuvrability, even when reversing.
System requirements
The vehicle must be equipped with ECAS or also with eTASC and an LACV-IC on
the last axle. This is necessary to ensure that the level is readjusted quickly to
normal level - thus reducing the wheelbase - when the last axle is relieved as the
vehicle drives into a corner.
• ECAS
(eTASC)
• 4S/3M on the last axle
• LACV-IC
• Additional pressure sensor on axle e-f
Legally defined turning circle
The BO BOforce circuit specifies the legally defined turning circle that is permissi-
ble by law for trailer vehicles. The outer diameter of the circle is 25 m, the inner di-
ameter of the circle 10.6 m. With OptiTurn the legally required turning radius is
more easily complied with.
Activation OptiTurn
Automatic and manual activation options are available.
Automatic activation
• After driving at a higher speed and when the speed drops below a parameter-
ised speed (max. 30 km/h): The function starts with a delay of 60 seconds. The
function is deactivated when the parameterised speed is exceeded.
• Immediately upon curve detection: The function starts immediately on entering
a curve below the defined speed. The function is deactivated once the vehicle
had driven through the curve.
• Only with partial/full load: With unladen vehicles, the function remains deacti-
vated automatically. The TEBS E switches to the automatic lifting axle function.
