grambles423
Automotive Engineer
- Location
- Alabama
- Car(s)
- 2008 GTI
Taken from a Technical Memorandum. Even though there isnt any true technical mechanical discussion, its a good functionality approach so we can get into the mindset of what is to come:
Discuss
Electronically controlled front-axle transverse differential lock (VAQ)
For the vehicles developed in the MQB system – and for the first time
in front-wheel drive production vehicles – an electronically controlled
front-axle transverse differential lock (VAQ) will be available. VAQ
passed grueling endurance tests at the 24-hour race at the Nürburgring
in the past two years. The electronically controlled front-axle transverse
differential lock is a powerful addition to the familiar ASR, XDS and ESP
control systems. The new system is based on a multi-plate coupler that
is located between the differential cage and the right drive shaft. The
pressure required to actuate the VAQ is produced and regulated by an
electrically-powered hydraulic pump. A control unit continually adjusts
for the optimal locking power as a function of the driving situation.
For example, this prevents slip of the wheel with the least grip in a split
friction (split-μ) situation or slip of the wheel on the inside of the curve in
turning situations. In dynamic driving, VAQ applies the drive torque to the
wheel on the inside of the curve and the outer wheel on the road according
to the different vertical wheel forces. The vehicle remains very neutral
right up to its performance limits by this so-called torque vectoring effect.
Curves can therefore be driven more precisely and with greater stability
than ever before with a front-wheel drive car. The traction disadvantages
of front-wheel drive vehicles are essentially eliminated. Significantly more
agile driving behaviour and higher speeds through curves also generate
even more driving fun and better performance.
Discuss