ADVANCES 2013 Issue 37 Page 1
Driving Automotive Safety
ADVANCESSemi-automated driving:Now it all makes sense360 degree radar:AC1000 sets the standard
OSS engineering: A rolling revolution in safety
The leading edge:• Rotary pretensioner aids packaging• SHI2 inflates large curtain airbags• Lane keeping now in closed loop• SDE 2 supports semi-auto driving
2013 Issue 37
ADVANCES 2013 Issue 37 Page 2
When I passed my driving test over three
decades ago, I was very proud to show my
license to my father and one of the things I
remember him saying was: “Accidents don’t
happen: they’re caused.”
Even now, in the days of ABS, ESC and
advanced driver assistance systems (ADAS),
this piece of advice holds true. Accidents still do
not just happen out of the blue. According to the
Swiss insurance company Axa Winterthur, the
main reason for vehicles colliding at crossroads
in Switzerland in 2012 was simply “inattention
and distraction” (29% of cases). Not paying
attention to the right of way was the cause in
21% of these accidents.
Human beings can be exceptionally smart
and flexible when it comes to carrying out
different tasks, including driving a vehicle. We
have a tendency, however, to pay less attention
to what is happening on the road during longer
or routine journeys and when we have an
accident it is often because we made the wrong
move or did not react properly.
ADAS behaves quite differently. Systems have
only a limited scope of tasks, but they react very
quickly and reliably. For example, a radar based
adaptive cruise control (ACC) system will control
the distance to the vehicle in front, and a camera-
based emergency braking system will continuously
monitor the environment and react immediately
– even if we are chatting with a passenger, or
very briefly looking at the whining children in
the back. This is the exact time when ADAS can
support us best.
Of course, it’s a strange feeling to know that
a car can brake by itself in an emergency and
for this reason, driver assist systems also warn
before they activate (usually the brakes). However,
From ADAS to automated drivingGuest editorial by Alfred Vollmer
In this issue
The road to automated driving .....................................................................................................................4 Lynette Jackson
AC1000 radar sets the standard ...................................................................................................................8 Sascha Heinrichs-Bartscher
The system-on-a-chip that powers S-CAM 3 ..........................................................................................12 Tal Babaioff, Mobileye
Occupant safety: A rolling revolution .......................................................................................................15 Swen Schaub
The leading edge ..........................................................................................................................................18 A selection of the latest technologies emerging from TRW research & development
centers around the world
In brief.............................................................................................................................................................20
Advances is published twice yearly for TRW Automotive customers and other external audiences. Please submit ideas for articles and inquiries to:
Lynette Jackson, communications director, +44 121 506 5315 [email protected]
John Wilkerson, senior communications manager, +1 734 855 3864 [email protected]
Roger Bishop, editor
This publication may include statements about our expectations for the future. These expectations are subject to numerous assumptions, risks and uncertainties, including those set forth in our most recent Form 10-K and Form 10-Q filed with the US Securities & Exchange Commission. We do not undertake any obligation to publicly release any update or revision to any of the forward-looking statements.
Quill Communications Inc, graphic design and layout
Point of view
ADVANCES 2013 Issue 37 Page 3
sometimes braking is required immediately – for
example when a pedestrian suddenly steps out into
the road, leaving no time for driver warning or any
delay in taking control of the vehicle.
It is my view that systems should intervene
if the driver is not paying attention. Interior
cameras can be a very effective means of
monitoring concentration and checking whether
a driver is actually looking ahead and has his
eyes open. If a driver is looking elsewhere
then, in the best case scenario, there is at least
a two second delay before he can understand
the current driving situation, process all the
relevant information and react accordingly.
That’s two seconds when a vehicle can travel
almost 28 meters at 50 km/h without braking. If
an automatic emergency braking (AEB) system
were to activate, or the vehicle maneuvers to
avoid an obstacle within those two seconds
without warning, this would surely be a
considerable safety advantage.
For me, being able to use those two
seconds wisely has the greatest potential
right now because the systems behind it are
already available. Driver assist systems need
to be allowed to intervene immediately while
simultaneously bringing the driver’s attention
back to the road. If a driver is not paying
attention – looking behind at the back seat for
example – then the emergency systems should
be able to take control of a vehicle to help
prevent accidents.
For now though, according to the Vienna
Convention in an agreement reached even before
Neil Armstrong walked on Moon, the driver must
have control of the vehicle at all times.
Increasing acceptanceIt is important for drivers to learn to live with
advanced safety systems and trust them. What
use is a camera based lane keeping assist
system (LKA), for example, if the driver can
turn it off? It may well be that the driver is not
happy with the system’s design or its parameter
settings but then it is up to OEMs and Tier One
suppliers to carefully tune the system so that
drivers are comfortable with how it intervenes.
Experience shows that LKA systems are applied
quite frequently (much more so than AEB,
for example). So this is an area where DAS
in general really have the potential to make
progress.
We have become used to ABS and ESC,
but apparently we still use these systems too
tentatively. Axa Winterthur revealed that only
1% of young drivers (those who passed their
driving tests within the last three years) apply
the brakes hard enough to reach the maximum
deceleration. Even though 20 times as many
experienced drivers were found to achieve
maximum braking, 80% still fail to use the full
potential of modern brakes. This is an example of
where assistance systems, such as emergency
brake assist, should intervene as standard.
ADAS for compact carsIt’s a good thing that vehicle buyers are looking
at Euro NCAP scores and want to purchase five-
star cars. Now that the bar has been raised by
Euro NCAP, it is well known that in the future five
stars will only be awarded if the vehicle is fitted
with the relevant safety assistance systems.
I am certain that driver assist systems will
continue to progress over the next five years
and that prices will fall as a result of the ever
increasing numbers being fitted. In the first
instance, (stereo) camera and radar technology
– with sensor data fusion – will enable new
systems to be produced that will be affordable
for the compact class.
In premium class cars, it is naturally easier
to absorb the cost of incorporating complex
driver assist systems but, in my opinion, the
greatest art will be in making ADAS affordable
in the sub-compact class. With an aging
population, the need to better explain the
benefits of ADAS in the showroom and on test
drives is now urgent. Money is surely better
spent on ADAS than on alloy wheels.
Relieving stressLidar – a laser-based ranging system – is a
promising technology, and combined with lane
keeping assist (LKA), electrically powered
steering (EPS) and an array of software, we have
taken a small step towards automated driving.
Working together in a traffic jam assist function,
these systems can make a significant contribution
to driver comfort and safety by relieving them in
this stop-start mode and helping them to drive
stress-free after the traffic jam.
In my view, in the next 15 to 20 years, fully
automated vehicles will only be found on public
roads in tiny numbers but during this time the
industry will gather valuable experience relating
to the automation of driving functions, and a
very exciting driving era could begin. Until then,
it is certain that ADAS will significantly improve
safety and increase comfort.
Alfred Vollmer is the editor of AUTOMOBIL-ELEKTRONIK. A qualified electrical engineer, he began his career as a journalist specializing in semiconductors 27 years ago, and then worked as a marketing engineer for semiconductors for a few years. He has been a freelance journalist for over 20 years and more recently has been focusing on vehicle electronics.
ADVANCES 2013 Issue 37 Page 4
The future of driver assistance and semi-
automated driving systems has never looked
brighter. Pressure to improve road safety is
coming from all sides – the US government,
in the form of the National Highway Traffic
Safety Administration (NHTSA); the European
Commission; the World Health Organization; and
numerous consumer bodies, most notably New
Car Assessment Programs (NCAPs).
Regulation and new NCAP ratings are tangible
market drivers while vehicle manufacturers – and
even non-automotive companies like Google – are
ensuring there is plenty of media hype on the topic.
(See Issue 36 for more on the market drivers for
safety).
According to a 2012 J D Power survey
of 17,400 vehicle owners, 37 percent of all
responders initially said they would be interested
in purchasing a fully automated car. However, that
figure dropped to 20 percent once they learned
the technology would cost an additional $3,000.
Even at that price point 25 percent of male vehicle
buyers were willing to pay for a fully automated
vehicle along with 14 percent of women.
Now, the main questions being asked are:
what are the technologies behind the ‘semi-
automated’ buzzword; and what will the roadmap
look like that takes us, eventually, to a vehicle
that will drive us to work while we deal with the
overnight emails?
Today’s Driver Assist Systems (DAS) are
mostly independent functions using input from
sensors to support the driver or respond to
an emergency situation. There is a difference
between emergency or safety functions such as
automatic emergency braking (AEB), and comfort
functions like lane centering assist (LCA) or
lane keeping assist (LKA). And there is another
distinction between systems that respond for a
limited time period of time, such as LKA which
‘nudges’ a vehicle back when an unintended lane
departure is detected, and those that provide
The road to automated drivingBy Lynette Jackson
AbstractAutomated driving is a key topic of discussion in the automotive safety arena and, with the enabling technologies on production vehicles today, the road ahead for its development is clear. TRW has strong experience in three core areas that can help to make semi-automated, highly automated and fully automated driving a reality – sensors, electronic control and actuation.
ADVANCES 2013 Issue 37 Page 5
continuous support, like LCA helps ensures
vehicles remain in the center of
the lane.
Semi-automated driving describes situations
when support is applied for an extended time
period. For example, adaptive cruise control (ACC)
and LCA could work at the same time to control
longitudinal and lateral driving in a highway
driving situation to enable a Highway Driving
Assist (HDA) function (see panel). What makes
semi-automated driving functions attractive is that
they support the daily driving experience. In other
words, the consumer has made an investment
that is not there simply as an emergency back-up
but provides tangible value every day.
The semi-automated functions in production
today will become mainstream in the next
five to ten years with technology advances
accommodating greater levels of intervention
and driver support at higher speeds. Fully
automated driving will require a complete
vehicle-to-vehicle and vehicle-to-infrastructure
network. These technologies continue to evolve
and global experts agree that the time is right to
begin introducing them to world roadways. This
is planned to begin in the next three years, and
should accelerate as applications mature and
driver acceptance is achieved.
The principal components of semi-
automated driving technologies – sensors,
controllers and actuators – could be described
as the eyes, brain and muscle of systems.
TRW’s focus todayAlongside global vehicle manufacturers, TRW
is currently using these components to develop
semi-automated driving technologies that will be
in production in the next three to five years. These
will cover the three phases of driving supported
by active systems – ‘normal driving’ involving
comfort features such as ACC Stop & Go, traffic
jam assist (TJA) and HDA (see panel on page 5);
the ‘emergency’ phase that uses the same sensor
configuration at a higher level of intervention to
provide AEB and emergency steering assist (ESA);
and the ‘pre-crash’ scenario that covers the
timeframe where an accident is unavoidable and
occupant safety systems (OSS), like active buckle
lifter (ABL) and active control retractor (ACR), are
prepared for the oncoming crash.
The industry is moving in the direction
whereby data fusion between a forward-looking
camera and radar will be virtually a standard
requirement in support of advanced longitudinal
control functions. Today, the industry norm is for
this processing to take place in the radar unit
because all the decision-making and arbitration
in forward-looking longitudinal control functions
are classically in that sensor. (The camera can
have its own connection to the steering, through a
Key semi-automated driving developments
Two developments, requiring high levels of data fusion, look set to make important contributions to
coming generations of vehicles fitted with semi-automated driving systems.
Traffic Jam Assist (TJA)In the near future, the combination of longitudinal vehicle control (such as ACC Stop & Go) and
lateral vehicle control (such as lane centering assist) will help drivers in heavy traffic situations at
low speeds down to a complete vehicle standstill – Traffic Jam Assist. This function will enable a
car to follow the vehicle in front while keeping in its lane, up to a specific vehicle speed. The driver
may overrule the function at any time.
This will be a first step towards semi-automated driving, although still limited to specific low-
speed scenarios. The benefits are a high comfort level in monotonous situations and the potential
to reduce accidents caused by inattentive drivers. The Human Machine Interface (HMI) will be
designed to keep the driver in the loop as the ‘master controller.’ TRW’s TJA uses the same sensor
configuration (the video camera and a radar with sensor data fusion) as automatic emergency
braking (AEB) and emergency steering assist (ESA).
Highway Driving Assist (HDA)Highway Driving Assist will involve the integration of radar, cameras, and GPS map data. The
forward looking radar is shared with the ACC Stop & Go ACC feature that keeps a vehicle at a
set speed while slowing if the car ahead slows, or if another car cuts across the lanes in front of
it. Braking can be strong but, typically, not emergency braking. The forward-looking camera that
makes up today’s lane centering assist (LCA) keeps the car within a few centimeters of the center
of the lane. The driver can easily override steering inputs at any time. Additional side-looking
radars complete the 360-surround-view and enable HDA to monitor traffic in neighboring lanes as a
prerequisite for a Lane Change Control (LCC). This allows the vehicle to change lanes in a semi-
automated mode if requested by the driver. Integration of these features – ACC Stop & Go, Lane
Centering and Lane Change Control – will enable highly automated driving in specific scenarios.
ADVANCES 2013 Issue 37 Page 6
separate CAN connection, providing lateral control
functions that are purely camera based.)
However, semi-automated driving requires
the integration of additional sensors – perhaps
navigation data and outputs from ultrasonic
sensors – in which data fusion becomes much
more complex. At this level, TRW engineers
recommend a change in architecture to a Safety
Domain ECU (SDE). SDE is a separate ECU that can
allow the extension of DAS and semi-automated
driving functionality and handle the increased
bandwidth of data. For example, if it is required to
fuse some ultrasonic outputs on top of a forward-
looking radar and a camera in an ACC Stop & Go
system, or if a car manufacturer wants to move
towards 360 degree sensing, a centralized data
fusion unit is the most effective option.
The challenge for highly automated driving –
besides the legal aspects – is to bring the driver, who
may be driving hands off and possibly be distracted
by non-driving-related tasks (such as reading
or typing) back into the loop within a specific
timeframe, if necessary.
Redundancy issuesDuring this delay, which might be in the range of 5
to 10 seconds, all systems need to remain working
in a way that safety is assured for all road users.
So, on top of enabling system features, highly
automated driving raises considerations of
Safety systems and the three driving phases
The ‘emergency’ driving phase uses safety features working with the same sensor configuration as the comfort features in the ‘normal’ driving phase. The ‘pre-crash’ phase is the timeframe in which an accident is unavoidable and occupant safety systems (OSS) are prepared for a crash
▲ ▲LPB LPS
Last point to brake Last point to steer
Forw
ard
colli
sion
w
arni
ng (F
CW)
Hap
tic w
arni
ng
Brakeprefill CMB AEB
Normal Driving Phase (DAS like TJA, ACC, HDA)
• Driver assist features like – ACC Stop&Go – Traffic Jam Assist – Highway Driving Assist
Emergency Phase(AEB, Emergency Steering Assist)
• Collision Warning (optical, haptic, acoustic)• Brake Prefill for immediate braking support• Maximum brake support when reaching the last
point to brake (full deceleration applied)• Last point to steer: Emergency Steering Assist (ESA)
supports the driver in an emergency situation where the driver initiates an evasive steering maneuver
• Additional steering torque is applied to assist the driver during evasive maneuvers and assist the driver in stabilizing the vehicle
Pre-CrashPhase
• Crash unavoidable• Preparation of OSS
systems, eg – Active Buckle Lifter – Active Control Retractor
ADVANCES 2013 Issue 37 Page 7
system redundancies, fall-back strategies, safe
stop scenarios and last, but not least, the legal
responsibilities of drivers and car manufacturers.
The process for testing future DAS and
semi-automated functions at TRW begins with
software simulations. These are then integrated
into a complete build using existing hardware. In
this hardware-in-the-loop set-up, the system is
injected with data – either artificially generated
or recorded from a real-life scenario – to enable
it to replicate a vehicle’s behavior. This is then
taken forward onto a vehicle.
Real world testing takes place on the
road. For example, TRW uses ten ‘reference
roads’ near its R&D center in Koblenz, Germany.
These roads all have different characteristics
in terms of traffic density, bends, curvature,
number of lanes, rural and urban environments
and so on. TRW has defined tests which are
repeated two or three times during a program to
arrive at a statistical statement on the
development’s progress. By repeating
the tests, engineers are able to
calculate the number of false alarms, as
well as how many critical observations
have been reported correctly.
The final, vital, element is to test
the systems in a broad mix of countries
and at extremes of temperature. This is
to cover, for example: left-hand and right-hand
driving conditions; the winding roads of the
Italian Alps; the arid environment of a desert;
and the cool of an arctic region. Cameras, in
particular, need to be tested in a wide range of
light and weather conditions.
The future is nowTRW is working with a number of vehicle
manufacturers in several regions globally to
determine the most effective way of introducing
semi-automated driving functions. However,
it is certain that they will come and will be
on mainstream vehicles. The challenge is to
manage consumers’ expectations and introduce
technologies in a consistent way to encourage
their wide acceptance. The most significant benefit
of moving from emergency assistance to semi-
automated driving is that customers will experience
the benefits every time they get into their cars.
MidTraffic jam, city driving HighRural roads, highway
Max. speed for system usage
Assis
ted
Sem
iau
tom
ated
High
lyau
tom
ated
Fully
auto
mat
ed
Degr
ee o
f aut
omat
ion
LowParking maneuver
Traffic jamassist
ACC Stop&Go
Park assist(lateral only)
Park assist(lateral + longitudinal)
Lane keeping assist
Highway driving assist
Highway chauffeur
Highway pilot
Automated driving vs traffic conditions
The technologies needed to achieve different levels of automated driving in a range of traffic conditions
ADVANCES 2013 Issue 37 Page 8
Safety systems using radar are poised to
become readily available technologies on even
the most modest of vehicles thanks to advances
in radio frequency technology and electronics
that have led to the development of AC1000. It
will help car manufacturers achieve the highest
NCAP ratings for vehicles across their ranges,
including the smallest which have traditionally
been highly sensitive to the cost of sophisticated
safety features.
AC1000 has been designed as a 77
GHz scalable radar family which will enable
functions including lane change assist, blind
spot detection, cross traffic alert, side impact,
pedestrian sensing and collision warning.
Sensors can also be integrated with the vehicle
Xenoy front housing
EMC screen
RF PCB
DSP board
Aluminum rear housing
AbstractLeading edge technologies, imaginative design thinking, proven experience and good ‘cost cycle’ timing have converged to result in an advanced radar sensor family – AC1000 – capable of bringing superior features such as automatic emergency braking to cars at a cost that will appeal even to manufacturers of A and B segment vehicles.
AC1000 radar sets the standard
ADVANCES 2013 Issue 37 Page 9
powertrain, braking and electric power steering
systems to provide automatic emergency
braking (AEB) and traffic jam assist.
The significant technical developments
involved are the substitution of the gallium arsenide
(GaAs) chip with a much simpler and lower cost
silicon germanium (SiGe) chip and integration
of the voltage controlled oscillator, or VCO – the
‘heartbeat’ of the radar – on the SiGe chipset. In
addition, the forward-looking AC1000 sensor uses a
technique called ‘digital beamforming,’ or DBF (see
panel overleaf) which, in simple terms, gives it a
capability comparable with much larger and more
expensive scanning radar systems.
Technology migrationLooking back at the history of automotive radar
systems developed by TRW, AC1000 has its
roots in the AC10 77 GHz system that went into
the Volkswagen Phaeton more than ten years
ago, followed by the AC20 developed first for the
Passat. Both were based on GaAs technology.
Even at this time TRW realized that radar
technology would migrate towards vehicles
in the C and B segments and even A segment
cars. At that point, TRW decided not to pursue
exclusively the development of long range
radar, capable of detecting objects at 200 m and
beyond, but instead focus on further developing
its shorter range 24 GHz narrow band radar for
city and inter-urban active safety applications.
AC100, launched in 2012, was the first TRW
radar to use a SiGE chipset and a pioneering
microprocessor that allowed significant
efficiencies in building a radar product and were
therefore key to its competitive price.
Euro NCAP is one of the drivers behind
the specifications that led to the evolution of
AC1000. Progressively raising the bar on the
requirements for a five-star safety rating has
accelerated the development not only of radar
systems, but also the fusion of radar with
camera systems and the complex algorithms that
enable them to detect and distinguish objects. In
truth, 24 GHz (AC100) radar offers a comparable
performance to 77 GHz (AC1000) systems for city
and inter-urban automatic emergency braking
(AEB) applications. However, to optimize a
set-up for detecting all types of pedestrian in
all circumstances requires a radar with a very
high resolution. This is where a 77 GHz (AC1000)
system with its higher bandwidth and eight
times higher resolution, comes into its own.
A scenario exemplifying this requirement
is that of a child running out from behind a
stationary vehicle who needs to be detected and
tracked as quickly as possible. The challenge
here is separating the child from the car
(which is a much stronger reflector) as early as
possible. This requires a radar with a very wide
field of view, or aperture ‘opening angle’, and a
high bandwidth. With this in mind, 24 GHz narrow
band radar technology has its limitations
Against this background, it is fortunate for
the industry that 24 and 77 GHz systems have
been more widely adopted. The effect has been
to see the cost-down-curve-over-time for 24
GHz systems flatten out over the last few years.
The 77 GHz cost reduction gradient has fallen
steeply towards it to the point where its higher
resolution, wider bandwidth and reduced cost
are of great interest to vehicle manufacturers.
AC1000 has been developed across multiple
locations. The antennas are being developed at
TRW’s technical center in Brest, France; with
the hardware design taking place at Solihull, in
Dual mode operation: Adapted field of view
TRW engineers are exploring two ‘opening angle’ settings in order to maximize AC1000’s capabilities to meet Euro NCAP requirements
Sensor FOV is adjusted with vehicle speed
ADVANCES 2013 Issue 37 Page 10
the UK; and algorithm development, testing and
project management being coordinated from
Koblenz, Germany.
The first product in the AC1000 product family
will be a forward-looking sensor using the digital
beamforming technique and will be available from
2015. This will be followed by a side and rear-
looking sensor.
Concealed sensorThe forward-looking sensor would typically be
mounted at the front of a vehicle, preferably in
the center or offset by up to 0.5 m to the side. It
could be concealed behind a logo if desired or
hidden behind a bumper provided it is made from a
material that minimally attenuates the transmitted
or received signals. On its own (without fusion with
a camera), the sensor can be used for adaptive
cruise control (ACC), forward collision warning
(FCW) and automatic emergency braking (AEB).
The rear/side-looking radars would be
mounted in pairs at the rear edges of the vehicle,
looking to the side and rear. Most of its core
components are shared with the forward-looking
sensor. Anticipated applications are lane change
assist, blind spot detection, and a rear cross traffic
alert function.
Testing and refinementCurrently, TRW engineers are testing and
refining the forward-looking sensor in the
AC1000 family for its anticipated first application
on a mainstream European vehicle. The system
has been designed so that the ‘opening angle’
can be changed in response to
the vehicle speed to optimize
radar field of view according
to the situation. For example,
at high speed the long range
mode is selected to achieve
maximum detection range
with a reasonable opening
angle. On the other hand, at
low speed adapting to urban
scenarios is achieved with
a maximum opening angle
– for example to detect a
Fusion architecture with optional CAN
Euro NCAP is progressively raising the bar for a five-star safety rating, accelerating the fusion of radar with advanced camera systems
AC1000 manufacture at Brest in France
pedestrian stepping out in front of the vehicle
and triggering AEB.
At the moment, TRW engineers in Koblenz
are exploring two operational modes to maximize
AC1000’s capabilities in line with Euro NCAP
requirements for pedestrian protection.
The final production calibration of the first
AC1000 application will, of course, be decided with
the vehicle manufacturer. However, even now it is
apparent that the AC1000 family is destined to make
an extremely important contribution to high end
active safety systems on all classes of passenger
car over the next few years.
For more informationSascha [email protected]+49 261 895 2762
ADVANCES 2013 Issue 37 Page 11
Key techniques make the difference
Two techniques within AC1000 are critical to its accuracy and reliability – the modulation scheme and
digital beamforming. Together, they contribute to a product that has some unique characteristics.
FMFSK modulation Frequency-modulated continuous-wave radar (FMCW) resolves both distance and speed of the
detected object by transmitting a signal that varies in frequency over a fixed period of time. This so-
called frequency ramp, running up and down, is absolutely linear. Detected objects are associated
with frequencies and not directly with range and velocity, so in order to resolve
these parameters, groups of detections, in a process called ‘matching’, need to be
analyzed by the system electronics. During the matching process there is potential
for errors which, in the worst case, can lead to the appearance of ghost objects
which are clearly undesirable in a system that, in the case of AEB, could fully apply
the brakes.
For AC1000, TRW has taken a different approach. The FMCW ramp, for this
purpose, is overlaid with small steps (frequency shift keying, or FSK). The direct
measurement of distance and speed from a single ramp can therefore be achieved.
In this way, the AC1000 avoids detecting ghost targets already identified by the
tracking algorithm. This results in minimal object confirmation time which is key to a
high Euro NCAP score.
Overlaying FMCW is a technique called frequency modulated frequency shift
keying (FMFSK) which, in simple terms, puts steps on the linear ramp, turning its
profile into a staircase.
Digital beamformingThe AC1000 radar integrates ‘digital beamforming’ (DBF) technology which allows
multiple directional beams to be transmitted and received simultaneously and
therefore allows the system to track multiple objects at the same time. DBF is
computationally very efficient as it allows the beam to be adapted according to the application which
is relevant at the time. DBF integrates antenna technology and digital technology. The beamforming
is achieved via a processor used in conjunction with an array of antennas to provide a versatile form
of spatial filtering. With this technique, the operations of phase shifting and amplitude scaling for
each antenna element, and summation for receiving, are done digitally.
Digital processing requires that the signal from each antenna element is digitized using an A/D
converter. For beamforming, the complex baseband signals are multiplied by the complex weights to
apply the phase shift and amplitude scaling required for each antenna element.
77 GHz RF module architecture
• Multi-static operation: 1 transmit (Tx) and 4 receiving (Rx) antenna
• Digital Beamforming algorithm to calculate target angle and obtain high angular resolution
• Flexible SiGe transceiver to address different modulation schemes
• Low cost planar antenna technology
ADVANCES 2013 Issue 37 Page 12
Driving today is an increasingly complicated task.
Traffic has become more dense, it moves faster
and there are many potential driver distractions in
the modern ‘connected’ world. Market pressures
– led by New Car Assessment Programs (NCAPs)
around the world – and legislation are encouraging
technologies that make driving safer and, among
these, are Advanced Driver Assistance Systems
(ADAS) that can help to dramatically reduce
accidents, or their seriousness.
Mobileye develops and provides the
automotive industry with ADAS capabilities
based on monocular vision. The technologies
include object detection (vehicles, trucks,
motorcycles and pedestrians), lane detection,
traffic sign recognition and high/low beam
control.
These technologies are powered by the
company’s system-on-chip (SOC) – EyeQ – and
allows multiple applications to run in parallel (see
panel). For example the lane detection technology
supports lane-departure-warning as well as lane-
keeping (on the Hyundai I40 and Kia Optima using
TRW’s S-CAM 2 video camera) and traffic-jam
AbstractVehicle manufacturers and their suppliers are seeking the most advanced and reliable technologies to support the latest – and future – generations of advanced driver assistance systems (ADAS). Among these are the vision systems powered by Mobileye’s EyeQ system-on-chip.
System-on-a-chip powers tomorrow’s cameras By Tal Babaioff, Mobileye
EyeQ is a family of highly integrated chips supporting intensive processing using specially designed processing modules, general purpose CPUs for control and IO capability for video input and car interface
• 2 x floating point hyper-thread 32bit RISC CPUs
• 5 x Vision Computing Engines (VCE)
• 3 x Vector Microcode Processors (VMP)
Mobileye’s EyeQ2 system-on-chip
ADVANCES 2013 Issue 37 Page 13
assist. Object detection is the enabling technology
for forward-collision-warning as well as collision
mitigation by braking (with radar fusion on Chrysler
Jeep Grand Cherokee and Jeep Liberty, also using
S-CAM 2). Object detection is also addressing
pedestrian protection – such as the world’s first
automatic pedestrian emergency braking system.
ADAS based on Mobileye technology first entered
the market in 2007 with car manufacturers including
BMW, Volvo, GM, Ford, and PSA. The current
installation base exceeds 2 million vehicles.
During 2013 new applications based on
Mobileye technology have been going into serial
production, most notably vision-only adaptive
cruise control (VO-ACC) and Automated Emergency
Brake (AEB). Current AEB applications allow for
limited braking force but, in 2014, a full braking
EyeQ is a family of highly integrated chips supporting intensive
processing using specially designed processing modules, general
purpose CPUs for control and IO capability for video input and car
interface (including high speed CAN). The architecture and computing
engines were designed to allow the processing of images to extract
interesting regions and features combined with support for powerful
classification and tracking engines. It comprises (in EyeQ2) two floating
point, hyper-thread 32 bit RISC CPUs, five Vision Computing Engines
(VCEs), and three Vector Microcode Processors (VMPs). The MIPS34K
CPU manages the five VCEs, three VMP and the direct memory access
(DMA), the second MIPS34K CPU and the multi-channel DMA as well
as other peripherals. The five VCEs, three VMPs and the MIPS34K CPU
perform all the intensive vision computations required by the multi-
function recognition bundle. This gives the EyeQ2 exceptional computing
power, enabling the high functionality bundles to run on a single
processor based camera.
The original EyeQ supports vehicle detection (forward collision
warning, adaptive headlight control) and lane detection (for lane
departure warning or headway monitoring & warning). Alternatively,
EyeQ runs a combination of lane departure warning, traffic sign detection
and adaptive head beam control.
The second generation processor (in production since 2010), is
more powerful by a factor of six than the first and supports all the above
algorithms (and more) on a single platform as well as video input from two
high-resolution image sensors and ‘video out’ capabilities with graphic
overlay. The third generation – EyeQ3 – is more powerful by factor of six
than EyeQ2 and allows processing of multiple high resolution sensors in
parallel, resulting in range extension and enhanced features.
Working with customersEvaluation platforms are critical to the applications engineering process
conducted by tier one suppliers and automotive manufacturers as they
build ADAS capabilities into new car models.
Mobileye’s EPM2 evaluation platform, for example (based on EyeQ2),
is designed to run multiple bundles of Mobileye’s Image Processing
Applications for technology evaluation in a series-like environment. It is
capable of running the following vision applications: vehicle detection,
lane and road analyses, traffic sign detection, intelligent headlight control
and pedestrian protection.
EPM2 supports the Micron MT9V024 CMOS sensor based camera
module, RCC version. The typical horizontal field of view for capturing
video images is 40°.
The evaluation platform can be run in two modes – standalone and
PC HOST-controlled, with EPM2 accepting video packets downloaded
over an Ethernet bus from an external PC via the SIM.
The basic platform includes: EPM2 plus SIM development boards,
camera module and power supplies. The offline system includes:
PC notebook with CAN interface, Mobileye EyeQClient application
(incorporates Mobileye Off-line application), SIM Board, optional CAN
card and cables. The package can also be expanded as a software
development platform. A board support package (SW) enables engineers
to port their own code onto the MIPS processors.
A unique image processing architecture
TRW’s compact S-CAM 3 camera, using the powerful Mobileye EyeQ3 chip, was being unveiled at IAA, Frankfurt
ADVANCES 2013 Issue 37 Page 14
force, vision-only AEB will be introduced. These
advances are being driven by Euro NCAP’s new
scoring system that will make it impossible for
cars to achieve a five-star safety rating without
active ADAS capabilities. Vision-only solutions or
systems based on the fusion of radar and camera
sensors are key technologies. TRW is winning a
significant share of new business to meet these
requirements with S-CAM 2 and the latest S-CAM
3 being formally unveiled at the international
automotive show, IAA 2013, in Frankfurt.
S-CAM 3 uses Mobileye’s latest EyeQ3
technology. It has six times the processing
power of the current generation, providing
a higher level of performance and several
advanced new functions. The camera will be
launched early in 2015 and feature on a number
of 2016 model year applications.
Delivering all the functions of its
predecessor – lane departure warning, forward
collision warning, headlight control, traffic sign
recognition and pedestrian detection – S-CAM
3 has an increased vertical and horizontal field
of view (horizontal 52°and vertical 39° compared
Mobileye’s third generation SOC – EyeQ3 – is more powerful by a factor of six than its predecessor. This is particularly important in advanced pedestrian protection applications
with 42°and 27° in the current generation)
and a higher definition imager (1280 x 960
pixels compared with 752 x 480).
The enhancements bring more
advanced features into S-CAM 3’s
range of capabilities including: AEB,
Adaptive Cruise Control (ACC) for
highway conditions, Advanced Traffic
Sign Recognition, Object Character
Recognition, Lane Centering, Large
Animal Detection, Active Body Control,
Construction Zone Assist, Traffic Light
Detection, and General Object Detection.
Laboratory to roadResearch, development, testing and
validation are central to Mobileye’s mission and,
to this end, the team has engineered a highly
automated vehicle that allows the driver to
delegate full control for a limited time. The solution
is unique in being based on current core series
hardware and technologies in series production
today, or soon to be introduced. Apart from the
front-looking camera, the Mobileye vehicle makes
use of a bumper camera and top view cameras
around the vehicle. This combination is used to
keep the vehicle a safe distance from parallel
driving vehicles and any other objects.
The biggest challenge in providing AEB
systems is the ability to properly detect all
required objects (vehicles and pedestrians) and
provide accurate measurements – for example
distance or relative velocity – in all weather
conditions, day or night, and in any geographical
location.
To validate this process and ensure
no ‘false positives’ are signaled, Mobileye’s
research team checks both the true positive
performance (against ‘ground-truth’ and on
test tracks) as well as against clip databases.
A complete validation against large scale
databases involves tens of thousands of hours
of driving. These databases include real-life
driving scenarios. Then there are separate and
extensive validation campaigns conducted with
both Tier One suppliers and car manufacturers.
For the future, Mobileye is well advanced
with the development of new technologies
such as: general object detection; 3D world
representation based on motion; animal
detection; road profile reconstruction; and
traffic light recognition. These systems are being
engineered for sourced business so applications
based on them could be launched as early as
2014 to 2016 by car manufacturers.
Tal Babaioff is senior director business development at [email protected]+972 2 5417 340
ADVANCES 2013 Issue 37 Page 15
While many of the basic components of
occupant safety systems (OSS) remain in
the form of seat belts and airbags, these
technologies continue to be transformed both
as individual restraint systems and as part of
integrated systems working in harmony to help
protect passengers.
Much has been learned in the five decades
that have passed since the introduction and
subsequent widespread adoption of the seat
belt. Laws requiring seat belts are becoming
universal in the motoring world with good reason
– they are still the first line of defense when a
crash occurs and all children and adults in a
vehicle should be properly buckled up before
their journey begins.
Inflatable restraints added an important
enhancement to the occupant safety landscape,
and over the past 20 years engineers have
learned how frontal, side, knee and new airbag
concepts can help protect passengers through
adaptive technologies. Dual stage inflators were
a great step forward and now there are vented
airbags that can adjust depending on passenger
size and how close the passenger may be to the
deploying airbag. Special tethering devices, bag
shapes and even how the airbag is folded can
also help systems adjust to specific occupant
sizes and crash characteristics.
Adding seatbelt innovations such as
pretensioners and load limiting retractor designs
that help manage occupant energy and work
together with the adjustable aspects of airbag
systems, has resulted in advanced adaptive
AbstractToday’s occupant safety systems feature adaptive functions that are tailored to occupant size and position, and that perform active functions that help to better position passengers before a crash even happens. They can even help you buckle up, make the ride more comfortable, and serve as warning functions when danger may lurk.
Occupant safety: A rolling revolution
TRW airbag technologies are adaptable to different vehicle sizes, types and the characteristics of the occupant cabin. The modular kit approach to the curtain airbag, shown, enables the company to cover vehicles from compact cars to Sport Utility Vehicles or vans with three rows of seats
ADVANCES 2013 Issue 37 Page 16
occupant safety systems that can help protect
passengers across many crash scenarios.
And now these systems are going beyond
just the role of protecting passengers in a crash;
they are an integral part of the evolution of safety
systems and are playing a role in helping to warn
drivers and assist them in avoiding crashes.
Versatile beltsFor example, TRW makes two active, reversible
seat belt technologies – the active buckle lifter
(ABL) and the active control retractor (ACR).
Both utilize a motor to provide specific functions
such as making buckling up easier and more
comfortable, or rapidly removing seat belt slack
Normal driving condition
Accident avoidance phase Crash phase Rescue phase
Comfort systems Assistance systems Pre-crash systems Restraint systems Rescue systems
Accident probability
Comfort functionsDrivingsupport
Occupantconditioning
Early activation,adaptivity
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Low
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Integration of active and passive safety systemswhen active safety sensors indicate that a crash
may occur due to vehicle instability or rapid
closing speed on another vehicle or object.
Beyond the opportunity to better position
the occupant prior to a crash, systems like these
can be used as a haptic feedback mechanism
in which the belt is vibrated to get a driver’s
attention. Haptic feedback that works through
direct contact with drivers has been shown to
be more effective than external warnings such
as flashing lights or audible buzzers that need
to be seen or heard and then interpreted. These
warnings alert only drivers and allow them to
better concentrate on the task at hand.
This capability can be particularly valuable as
new safety systems such as Automatic Emergency
Braking (AEB) are introduced. Combining ACR
with AEB is a natural evolution as sensors such as
cameras and radar pick up impending targets and
first look to warn drivers, and if they fail to react,
apply full seat belt slack removal to better position
them in case of a crash. In low speed urban
situations the use of the haptic feedback could
warn drivers of issues such as a potential collision
with a vehicle ahead or at the side, or a pedestrian
entering the vehicle’s pathway.
Lateral controlSeat belt technologies can also help drivers
stay in control during dynamic driving situations.
Taking cues from active systems, such as the yaw
rate sensors in the electronic stability control
(ESC) system, it is possible to determine when
a vehicle is losing lateral control. When this
happens, drivers tend to be thrown from side to
side, making vehicle control more challenging. In
this situation a management algorithm in the ACR
(or ABL) system will remove seat belt slack to
assist drivers in controlling their vehicles by better
fixing them in their seats.
TRW technologies also work in additional
pre-crash scenarios and assist passengers in
reducing the likelihood of being out of position
in a potential crash. Locking the belt retractor
helps to keep passengers fixed to the seat,
reducing the forward excursion of the body
towards hard objects like the instrument panel or
the steering wheel. This is important when hard
braking occurs, such as in higher speed AEB
maneuvers, as the head and body will naturally
move forward if not restrained and may not be in
an ideal position if an airbag is deployed.
Occupant safety systems can also be
pre-armed to reduce the time-to-fire (TTF) of seat
belt pretensioners and airbags in imminent crash
situations. Additional systems such as active seat
structures and external side pre-crash airbags
can be triggered before the crash to further
mitigate the impact.
Variable elements in the restraint system such
ADVANCES 2013 Issue 37 Page 17
as seat belt load limiters and airbag venting can
be pre-adjusted depending on pre-sensed crash
parameters such as impact direction, location,
predicted delta-vs-severity, actual occupant
position and posture and available occupant
classification data, such as size and weight of the
passenger, belted or unbelted, and so on.
In addition to the lateral pre-crash
external airbag TRW has developed a pre-
crash thorax side airbag with high energy
absorption capability. Tests have shown that
firing this airbag 15 ms before the collision
allows the airbag to be fully deployed and, when
combined with the movable seat structure that
rotates inboard 50 ms before the crash, can
significantly reduce the injury values retrieved
from biomechanical dummies, including chest
deflection.
Taking the wheelTRW is also a leading developer and supplier of
steering wheels – the primary human-machine
interfaces in vehicles. The steering wheel offers
prime opportunities for detecting various data
on which to base safety decisions. For example,
hands-on detection can help define driver
awareness and readiness during acceleration
or braking and can also indicate whether drivers
are maintaining a hand-on-the-wheel when
using systems like adaptive cruise control or
semi-automated systems.
Driver feedback can also be provided by
vibrating the steering wheel to support systems
such as lane departure warning, lane keeping,
automatic emergency braking and more. Another
innovation in the steering wheel is the use of a
small display area in the wheel’s rim that provides
a visual warning or indicator for various speed
assistance and Driver Assistance Systems (DAS).
The company has also researched sensing
systems within the rim that can monitor driver
wellness, including vital signs like heartbeat and
blood pressure.
TRW has been a pioneer and leader in the
area of active and passive safety integration
drawing on the company’s long experience in
both technology areas and its groundbreaking
ACR seat belt technology introduced more than a
decade ago.
Enhanced valueToday’s occupant safety technologies are more
innovative than ever before and are moving
ahead into exciting new territories as they
support the growth of active safety systems.
Whether its safety, comfort, convenience,
support of vehicle design, changing modes of
transportation, or semi-automated driving, TRW’s
occupant safety systems are evolving to meet
the needs of vehicle markets everywhere.
For more informationSwen [email protected]+49 179 232 7419
The steering wheel can both detect data, such as when a driver’s hands are on or off the wheel, and provide feedback through vibrating mechanisms and built-in displays
This large airbag deploys from the external side structure of the vehicle, covering doors, sill and B-pillar. It helps to absorb the energy of a side collision and reduces intrusions into the struck vehicle
ADVANCES 2013 Issue 37 Page 18
The leading edgeRotary pretensioner solves packaging problems
SHI2 hybrid inflator family extended for large curtain airbag applications
A new anchor seat belt pretensioner in a rotary configuration – known
as the APR1 – has been designed to help vehicle manufacturers
faced with challenging packaging situations. It will launch on
several European vehicle platforms in 2015.
APR1 is light, compact and designed to allow an easy
integration in vehicle interiors. There is no linkage element
necessary and only the normal seat belt webbing is visible in the vehicle
cabin. It is designed to deliver pretensioning forces of more than 3kN, which can help to
remove some seatbelt slack within milliseconds of a crash being detected.
When combined with TRW’s occupant protection seat belt and airbag options,
the APR1 helps form the basis of advanced adaptive occupant technologies designed
to help manage occupant energy in an unavoidable crash scenario. For example it can
be combined with TRW’s Active Control Retractor (ACR) system or Active Buckle Lifter
(ABL), that help to remove seatbelt slack before a crash occurs if a potential accident is
detected by a vehicle’s active sensors.
Norbert Kagerer, vice president Occupant Safety Systems engineering, TRW,
said: “The APR1 design offers vehicle manufacturers a number of options and
advantages compared with existing systems.
“We are seeing strong interest globally for APR1 due to its packaging, weight
and performance attributes. The rotary design helps deliver enhanced pretensioning
functionality and TRW is uniquely positioned to combine this technology with other
occupant safety and active safety technologies to sense and react to the unique
characteristics of a crash.”
TRW Automotive is extending its highly successful
SHI2 airbag inflator family to large curtain airbag
applications. The flexibility in package size and the
ability to deliver warm gas is now available for a bag
size up to 75 liters.
A small amount of propellant is used to heat the
gas to augment the airbag system energy. It produces
clean warm gas that allows the airbag to achieve
pressure requirements for first impact conditions and
cools to pressure requirements that help keep the
airbag inflated for rollover protection. The innovative
shock wave design enables rapid time to first gas fill
while the physical properties of the gas provide quick
deployment performance. A shock wave generated
by the combustion chamber travels the length of the
inflator to rupture a membrane on the opposite end.
This allows cold gas to initiate the bag fill process,
followed with warm gas that fills the bag to its desired
operating pressure.
The inflator delivers warm, clean gas, which
provides bag pressure retention desired in side impact
systems. Now, the SHI2 construction kit is extended
to three bottle diameters (25, 30 and 35 mm). Outputs
can be tailored from small thorax bag applications
to large A-D curtain applications. Serial production
of the 35 mm diameter versions will start in 2015 at
TRW´s North America inflator plant in Mesa, Arizona.
North America is the initial target market for such high
performance large curtain airbags due to the number
of larger SUVs currently sold.
Wolfgang Tengler, project manager SHI2 Inflators,
said: “Currently the standard product for large curtain
airbags is a cold gas inflator type, which is relatively
high in weight. With the SHI2 design we applied the
most effective warm gas principle. This combines
a high energy level of the delivered gas with the
increased requirements regarding rollover capability.
Compared with cold gas inflators, we are able to save
approximately 10% of weight and package size while
maintaining the performance level. ”
TRW’s SHI2 inflator family offers an inline design
to minimize the module attachments costs. The gas
exits opposite the electrical connection to
simplify fastening options.
This innovation will contribute to TRW’s
future as a leader in automotive safety
technology.
ADVANCES 2013 Issue 37 Page 19
Lane keeping assist gains closed loop control
TRW is launching a lane
keeping assist system with
closed loop control for the
first time on two vehicle
platforms for the European
market. The system will
go into production this
autumn.
Lane Keeping Assist
(LKA) integrates data from
a video camera sensor
with Electrically Powered
Steering (EPS) to apply a short counter-steer torque via the steering
system to assist the driver in preventing the vehicle from unintentionally
leaving the lane.
In conventional LKA systems, the technology is only active when
the vehicle is close to the lane borders, but with this closed loop version,
the steering angle is controlled more closely and the driver is ‘coached’ to
steer the vehicle away from the lane border back to the center of the lane.
In other words, the counter-steer torque is applied much more ‘gently’
than for conventional LKA systems. As for all LKA systems, the induced
torque generated by the EPS system can be easily overridden by the driver
at any time.
This technology is the first step toward a full lane centering system
where the EPS would help keep the driver in the center of the lane at all
times. Such technologies are starting to form the basis for future semi-
automated driving functionality.
TRW’s second generation Safety Domain ECU (SDE 2)
can integrate multiple driver assist system, chassis and
suspension functions within a single unit. It has greater
performance, compared with the earlier generation, and will
be a key technology in supporting semi-automated driving
and car2car communication.
Dr Hans-Gerd Krekels, portfolio and engineering
director, TRW Global Integrated Electronics commented:
“We have seen exponential growth in electronic systems
in cars – a trend that is set to continue with the further
penetration in active safety systems and increasingly
automated driving functions. As the number of sensors
increases in a vehicle, having a central safety ‘domain’
controller is vital in order to cope with the increase in
complexity and help to simplify electronic architectures.”
SDE 2 has a flexible, open architecture
structure to integrate software control
algorithms from both suppliers and third
parties including vehicle manufacturers, using
AUTOSAR 4.0 and beyond as a basis. The
scalable architecture can integrate functions
like driver assist or vehicle dynamics arbitration
and process data from multiple sensors (radar,
video camera and digital map information) to
enable 360 degree environmental sensing. It has
a high performance multicore microprocessor
architecture and, in addition to interfacing
on CAN or FlexRay, can support Ethernet
communication for high speed, high volume data transfer.
“Such developments are the first of their kind in the
industry today,” said Dr Krekels. “SDE 2 uses leading edge
electronics technology to support next generation vehicle
requirements. We are continuously looking at how we can
integrate a wider range of features into this single unit and
enable a higher degree of functionality and actuator control.
“To achieve the necessary high level of performance,
we can integrate performance micros, usually used in graphics
applications, as well as the Mobileye chip from our video
camera sensors. It can be directly embedded within SDE.”
TRW anticipates that its SDE 2 will be ready for
production by 2017. The first generation technology
started production this month with a German luxury car
manufacturer.
SDE 2 supports semi-automated driving
Steering wheel plant opens in Romania Employees and guests have celebrated the
opening of a new steering wheel leather
wrapping plant in Baia Mare, Romania. Some 300
people work at the facility with plans to increase
the workforce to up to 650 people by the end of
the year.
Ovidiu Ambrus, manager for TRW facilities
in Romania commented: “We have opened the
plant to meet current and growing requirements,
primarily for Audi. We have an excellent
workforce with the right skill set in this area.”
Belt drive EPS launches in ChinaWith TRW’s belt drive electric power steering (EPS)
technology being used for the first time on a global
vehicle platform launching in China, manufacture
of the system has begun at a new state-of-the-art
facility in Anting. Line capacity is expected to reach
around 400,000 units annually by 2014.
“Electric steering is a rapidly growing
technology globally due to the many advantages
it can provide,” said Peter Lake, TRW
executive vice president for sales and business
development. “Creating a regional production
base for our customers will provide a cost-
effective source for these fuel-saving and
emission reducing technologies. It will enable us
to expand our EPS footprint for the production of
global platforms and help to make it available to
our broader customer base in China and Asia.”
Safety.trw.com launchedA new internet site – Safety.trw.com – provides
the latest information on TRW technologies
and business developments, alongside wider
industry news.
The site can be viewed in TRW’s core business
languages and is regularly updated. Articles are
categorized under the headings of TRW News,
Technology and Industry, with the most popular
stories automatically featuring on the homepage.
New video material is also uploaded regularly.
Hybrid Ferrari has TRW steeringTRW is supplying electrically powered hydraulic
steering (EPHS) technology to La Ferrari’ – the
super car manufacturer’s first vehicle to have
hybrid propulsion.
Giorgio Marsiaj, president, TRW Italy,
explained: “TRW’s role as the official partner for
technological innovation on the new La Ferrari
super car demonstrates our ability to support
one of the most prestigious brands in the world.”
With more than 20 million systems in the
field, TRW’s EPHS is a proven solution for both
conventional and hybrid vehicle platforms,
delivering fuel economy and CO2 reduction
benefits comparable with full electric power
steering solutions.
Next generation SPR4 now readyNext generation SPR4 (snake pretensioner
retractor) seat belt assemblies are now ready
for worldwide customers with the product being
launched in North America, Europe and China.
The device uses a snake-like plastic piston,
instead of conventional metal components, to
transfer tensioning torque, resulting in a simpler,
lighter design and compact packaging.
Norbert Kagerer, TRW vice president
Occupant Safety Systems engineering, said:
“Tensioning force is generated more quickly
than with conventional systems and the damping
behavior of the plastic snake allows the initial
peak force, when impacting the pinion, to be
significantly lower compared with conventional
systems where two rigid steel elements impact
on each other.”
SPR4 will launch on a range of vehicles from
A segment cars up to sport utility vehicles (SUVs).
Driving Automotive Safety
In brief
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