Shift Magazine - April 2020 - 20

BRACED FOR IMPACT
ZF external side airbag is
proactive, not reactive

BY ALEXA ST. JOHN

mproving safety is often one of the largest motivating factors
behind innovation.
ZF's interest in safety technologies includes a new kind of
airbag.
The German auto supplier - which acquired U.S. airbag and
safety company TRW Automotive in 2015 - has developed an
external airbag safety system.
The system is called Prosip for Proactive Side Impact
Protection. With the system, the airbag deploys upon recognizing that a hit to the side of a vehicle is imminent and unavoidable.
Instead of reacting to a collision, the system takes a proactive approach to a potential crash with the goal of softening
its impact.
ZF networked external vehicle sensor systems - which
include cameras, radar, lidar and software - to the external side
airbags to create the Prosip system.
It is part of an ongoing reinvention of the
company mirroring that
of many suppliers. Over
the past four years, ZF
has gone from primarily manufacturing traditional automotive components to working on
advanced vehicle technologies such as crash-prediction systems, building much of that expertise through acquisitions.
ZF demonstrated Prosip to the media in Memmingen, Germany,
last July. The system has approximately 150 milliseconds to make
the decision to deploy the airbag, according to Georges Halsdorf,
lead engineer on the ZF advanced development team.
The bag sits below the doors, along the bottom sill, and grows
to the size of a life raft upon inflating.
Predictive airbags long had been a pipe dream for auto suppliers such as ZF.
This technology shows how significant sensors will be in making
more advanced vehicle technologies happen. Nontraditional seating arrangements in autonomous shuttles likely will require a
change in airbag placement and different passenger protection.
And growing V2X - or vehicle-to-everything - technology could
also enhance the use cases of a system such as this.
Halsdorf said full development of Prosip may take another four
to five years. He added that the external airbag system likely would
appear first in luxury cars with highly developed sensor sets. n

shift * april 2020

BENDING LASER
WELDING'S RULES
New process yields lighter, cheaper
doors, hoods and deck lids

BY JACK KEEBLER

eeting tougher emissions rules often means reducing
vehicle weight. Lighter vehicles burn less fuel. So makers
are using more aluminum in bodies and in stamped blanks
for body closures such as doors, hoods and trunks.
Shiloh Industries Inc. is working with carmakers to validate a
process to quickly and consistently make tailored laser-welded
aluminum blanks. This process is set for a 2021 vehicle model.
A tailored laser-welded aluminum blank is an aluminum sheet
composed of two or three pieces of different gauges, welded
edge to edge. Heavier-gauge aluminum is used only in the area
requiring added strength, such as a stressed aperture hinge point.
By using thinner gauge elsewhere, the cost, count and mass of
parts are reduced, compared with
using a single sheet of aluminum.
"Tailored laser-welded steel
blanks have been used for 20 years
or more," says Jim Evangelista,
director, R&D at Shiloh. "With a
welded blank, it is the only time
you're going to ask a weld to be
formable. The weld must bend
and go through a stamping die. It
will go into compression, tension
and a certain amount of elongation. With steel, it's not much of
a problem. Steel and its welds are not as brittle as aluminum."
Shiloh's usual steel-welding tech for blanks, however, would
not allow aluminum welds to accept the strains of stamping. The
breakthrough required two years of optimization and going back
to laser makers to ask what types of laser and frequencies were
used in the company's steel-welding processes.
Clamping and cleaning methods and weld-solidification speed
were all tweaked for greater ductility.
The result? Shiloh's experts say the welds survive draws
that the aluminum sheet itself will not accept without tearing or
damage. A draw is when the positive and negative halves of the
stamping die close on flat sheet, rendering a piece of shaped
metal, which is the part.
"People have been welding aluminum for years and years,"
Evangelista says. "But they have never asked that weld to bend." n

https://www.autonews.com/technology/teens-blind-spot-solution-clearly-winner https://www.autonews.com/technology/teens-blind-spot-solution-clearly-winner

Shift Magazine - April 2020

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