Munich. Alessandro Zanardi’s guest appearance at the DTM race
weekend at Misano (ITA) is now just a few weeks away. The
51-year-old Italian is at Vallelunga (ITA) on Tuesday and Wednesday
for a series of intensive tests with the BMW M4 DTM as he continues
to prepare as meticulously as possible for his outing in Italy.
Zanardi must familiarise himself with the many modifications in the
cockpit, which will allow him to push the DTM car to its limit
without using his prostheses.
BMW Motorsport engineers are learning with every car they modify for
Zanardi. They have once again developed many technical innovations for
his start in the DTM and at the 2019 Daytona 24 Hours (USA), including
a hand-operated braking system for the first time. Here is a detailed
look at the changes.
1. Hand-operated brake system.
When Zanardi makes his guest appearance in the DTM at Misano, he will
have a newly-developed hand-operated brake system at his disposal for
the first time. This replaces the combination of brake pedal with a
permanently attached artificial leg, which Zanardi has used to brake
on his previous outings in BMW race cars. The advantage of this new
system is that it requires less effort and is thus far easier to operate.
The brake lever is located to the driver’s right, in the centre
console area. The brake lines have been extended and laid from the
footwell to this lever. As a result, the pedal box, with the throttle,
brake and clutch pedals, is no longer necessary. The footwell in
Zanardi’s BMW M4 DTM is empty. The large brake cylinder has been
adjusted slightly, meaning Zanardi need not apply quite as much
pressure by hand as a regular DTM driver must with his foot to achieve
the required braking effect. Where a regular driver must apply 100 to
120 kilograms of pressure, a maximum 70 kilograms is sufficient for
Zanardi. As well as the size of the brake cylinder, the improved
leverage of the handbrake lever also makes the whole braking procedure easier.
For the new system to work, the BMW Motorsport engineers turned the
operating principle of the brake cylinder on its head. While the brake
pedal in a normal BMW M4 DTM exerts tensile force on the brake
cylinder, the handbrake lever in Zanardi’s car applies pressure to the cylinder.
As with every BMW M4 DTM, Zanardi’s car also has a parking brake,
which is used to build up preload pressure to allow the fastest
possible start. Like his fellow BMW drivers, Zanardi can operate this
parking brake via a button on the steering wheel. However, he can also
mechanically activate and release the parking brake via a lever on his
handbrake. This also allows him to prevent the car from rolling.
2. Centrifugal clutch.
In a standard DTM car, the drivers use a hydraulic clutch for the
start of the race and for pulling away from the pit lane before the
race and following a pit stop. In Zanardi’s car, a fully-automatic
centrifugal clutch is used instead. This automatically opens and
closes at certain engine speeds and is no longer operated by the
driver. The respective engine speeds are defined by BMW Motorsport
engineers as part of their meticulous set-up work. For Zanardi, the
system has the great advantage that he does not need to use one of his
hands to operate a clutch lever.
Initial tests with the centrifugal clutch have been very positive.
Both the pulling away slowly from the garage and the fast getaway at
the start or after a pit stop have worked seamlessly. The sprint from
0 to 100 km/h is roughly as fast with the centrifugal brake as with
the conventional system.
3. Gear shift.
In principle, Zanardi can change gears in his BMW M4 DTM via the
shift paddles on the steering wheel, just like his fellow drivers.
Furthermore, it is no longer necessary to operate a clutch in any
modern DTM car. Like all the other drivers, Zanardi uses the shift
paddle on the right side of the steering wheel to shift up through the gears.
When necessary, he can move down through the gears perfectly normally
with the respective shift paddle. However, as this procedure is
usually associated with a braking manoeuvre, for which the right hand
is needed, Zanardi can also downshift using a shift paddle on the end
of the brake lever.
4. Throttle ring.
The system, with which Zanardi accelerates in the BMW M4 DTM, was
adopted from the GT cars modified for him in the past. He accelerates
by using his fingers to pull on a throttle ring on the rear of the
steering wheel. The continuous ring can be operated with both hands,
or just with the left or right hand. This plays no role in the way the
system functions. The throttle ring is controlled using the same
sensors as the standard throttle pedal.
5. Steering wheel.
The steering wheel, including the throttle ring, is basically the
same as those used in the GT cars that Zanardi has driven in the past.
Only the buttons have been adjusted for his guest appearance in the
DTM. For example, a DRS button has been added. Meanwhile, the knobs
towards the bottom of the steering wheel, which are used to configure
driver aids such as ABS in GT cars, have no function in the BMW M4 DTM.
Note to editors:
In the coming weeks leading up to Zanardi’s guest appearance at
Misano, we will release several features regarding technology, safety
and other topics.