SENSOTRONIC BRAKE CONTROL

CHAPTER-1
INTRODUCTION
When drivers hit the brake pedal today, their foot moves a piston rod which is linked to the brake
booster and the master brake cylinder. Depending on the pedal force, the master brake cylinder
builds up the appropriate amount of pressure in the brake lines which - in a tried and tested
interaction of mechanics and hydraulics - then presses the brake pads against the brake discs via
the wheel cylinders.

By contrast, in the Mercedes-Benz Sensotronic Brake Control, a large number of

mechanical components are simply replaced by electronics. The brake booster will not be needed
in future either. Instead sensors gauge the pressure inside the master brake cylinder as well as the
speed with which the brake pedal is operated, and pass these data to the SBC computer in the
form of electric impulses. To provide the driver with the familiar brake feel, engineers have
developed a special simulator which is linked to the tandem master cylinder and which moves
the pedal using spring force and hydraulics. In other words: during braking, the actuation unit is
completely disconnected from the rest of the system and serves the sole purpose of recording any
given brake command. Only in the event of a major fault or power failure does SBC
automatically use the services of the tandem master cylinder and instantly establishes a direct
hydraulic link between the brake pedal and the front wheel brakes in order to decelerate the car
safely.

The central control unit under the bonnet is the centre piece of the electrohydraulic brake.
This is where the interdisciplinary interaction of mechanics and electronics provides its greatest
benefits - the microcomputer, software, sensors, valves and electric pump work together and
allow totally novel, highly dynamic brake management:

In addition to the data relating to the brake pedal actuation, the SBC computer also receives the
sensor signals from the other electronic assistance systems. For example, the anti-lock braking
system (ABS) provides information about wheel speed, while Electronic Stability Program
(ESP®) makes available the data from its steering angle, turning rate and transverse acceleration
sensors. The transmission control unit

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finally uses the data highway to communicate the current driving range. The result of
these highly complex calculations is rapid brake commands which ensure optimum deceleration
and driving stability as appropriate to the particular driving scenario. What makes the system
even more sophisticated is the fact that SBC calculates the brake force separately for each wheel.

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CHAPTER-2
SENSOTRONIC BRAKE CONTROL - THE BRAKES OF THE
FUTURE

Sensotronic Brake Control (SBC) is the name given to an innovative electronically controlled
brake system which Mercedes-Benz will fit to future passenger car models. Following on from
the Mercedes innovations ABS, ASR, ESP® and Brake Assist, this system is regarded as yet
another important milestone to enhance driving safety. With Sensotronic Brake Control electric
impulses are used to pass the driver’s braking commands onto a microcomputer which processes
various sensor signals simultaneously and, depending on the particular driving situation,
calculates the optimum brake pressure for each wheel. As a result, SBC offers even greater
active safety than conventional brake systems when braking in a corner or on a slippery surface.
A high-pressure reservoir and electronically controllable valves ensure that maximum brake
pressure is available much sooner. Moreover, the system offers innovative additional functions to
reduce the driver’s workload. These include Traffic Jam Assist, which breaks the vehicle
automatically in stop-and-go traffic once the driver takes his or her foot off the accelerator. The
Soft-Stop function – another first – allows particularly soft and smooth stopping in town traffic.

Mechatronics – a new term is gaining popularity within the automotive industry and is
rapidly developing into the catchword of a quiet technological revolution which in many fields
stands century-old principles on their head. Mechatronics brings together two disciplines which
in many cases were thought to be irreconcilable, namely mechanics and electronics.

Hence automobile functions which hitherto worked purely mechanically and partly with
hydraulic assistance will in future be controlled by high-performance microcomputers and
electronically controllable actuators. These either replace the conventional mechanical
components or else enhance their function. The mechatronic interplay therefore opens up
hitherto inconceivable possibilities to further raissafety and comfort levels of modern passenger
cars. For example: it

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safety and comfort levels of modern passenger cars. For example: it was only thanks to
mechatronics that an electronically controlled suspension system which instantly adapts to
prevailing conditions when driving off, braking or cornering -- thus providing a totally new
driving experience -- became a reality. In 1999 Mercedes-Benz launched this system under the
name Active Body Control (ABC) in the flagship CL coupé, thereby signalling the advent of a
new era of suspension technology.

This electronically controlled suspension system will quickly be followed by the

electronic brake system: Mercedes-Benz and Bosch have teamed up on this benchmark
development project which will shortly enter into series production at the Stuttgart automobile
brand under the name Sensotronic Brake Control -- or SBC for short.

It turns the conventional hydraulic brake into an even more powerful mechatronic
system. Its microcomputer is integrated into the car’s data network and processes information
from various electronic control units. In this way, electric impulses and sensor signals can be
instantly converted into braking commands, providing a marked safety and comfort gain for
drivers.

Figure 2.1: Brake pedal: electronics instead of a vacuum

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To turn to the technical side: when drivers hit the brake pedal today, their foot moves a
piston rod which is linked to the brake booster and the master brake cylinder. Depending on the
pedal force, the master brake cylinder builds up the appropriate amount of pressure in the brake
lines which – in a tried and tested interaction of mechanics and hydraulics - then presses the
brake pads against the brake discs via the wheel cylinder.

In the Mercedes-Benz Sensotronic Brake Control, by contrast, a large number of

mechanical components are simply replaced by electronics. The brake booster will not be needed
in future either. Instead sensors gauge the pressure inside the master brake cylinder as well as the
speed with which the brake pedal is operated, and pass these data to the SBC computer in the
form of electric impulses.

To provide the driver with the familiar brake feel engineers have developed a special
simulator which is linked to the tandem master cylinder and which moves the pedal using spring
force and hydraulics. In other words: during braking the actuation unit is completely
disconnected from the rest of the system and serves the sole purpose of recording any given
brake command. Only in the event of a major fault or power failure inside the 12V vehicle
battery does SBC automatically use the services of the tandem master cylinder and instantly
establishes a direct hydraulic link between the brake pedal and the front wheel brakes in order to
decelerate the car safely.

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CHAPTER-3
CONTROL UNIT

3.1 PRESSURE MODULATORS FOR EACH WHEEL:

The central control unit under the bonnet is the centrepiece of the electrohydraulic brake.
This is where the interdisciplinary interaction of mechanics and electronics provides its greatest
benefits – the microcomputer, software, sensors, valves and electric pump work together and
allow totally novel, highly dynamic brake management:
In addition to the data relating to the brake pedal actuation, the SBC computer also
receives the sensor signals from the other electronic assistance systems. For example, the anti-
lock braking system (ABS) provides information about wheel speed, while ESP® makes
available the data from its steering angle, turning rate and transverse acceleration sensors. The
transmission control unit finally uses the data highway to communicate the current driving range.
The result of these highly complex calculations is rapid brake commands which ensure optimum
deceleration and driving stability as appropriate to the particular driving scenario. What makes
the system even more sophisticated is the fact that SBC calculates the brake force separately for
each wheel.

The high-pressure reservoir contains the brake fluid which enters the system at a pressure
of between 140 and 160 bar. The SBC computer regulates this pressure and also controls the
electric pump which is connected to the reservoir. This ensures much shorter response times than
on conventional brake systems. Yet another advantage: full braking power is available even
when the engine is switched off. The hydraulic unit mainly comprises four so-called wheel
pressure modulators. They mete out the brake pressure as required and pass it onto the brakes. In
this way it is possible to meet the microcomputer’s stipulations while each wheel is slowed down
separately in the interests of driving stability and optimum deceleration. These processes are
monitored by pressure sensors inside the wheel pressure modulators.
3.2 Emergency braking: stopping distance reduced by up to three per cent :
The main performance characteristics of Sensotronic Brake Control include the extremely
high dynamics during pressure build-up and the exact monitoring of driver and vehicle behaviour

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using sophisticated sensors. Mercedes-Benz is thus moving into new dimensions of driving
safety. Take the example of the emergency brake: SBC already recognises the driver’s rapid
movement from the accelerator onto the brake pedal as a clue to an imminent emergency stop
and responds automatically: with the aid of the high-pressure reservoir, the system increases the
pressure inside the brake lines and instantly presses the pads onto the brake discs so that they can
get a tight grip the moment the driver steps onto the brake pedal. As a result of this so-called
prefilling of the brake system, the stopping distance of an SBC-equipped sports car from a speed
of 120 km/h is cut by around three per cent compared to a car featuring conventional braking
technology.

Thanks to electrohydraulic back-up, the performance of Brake Assist is also improved

further. If this system issues the command for an automatic emergency stop, the quick pressure
build-up and the automatic prefilling of the wheel brakes leads to a shorter braking distance.

3.3 Driving stability: precise braking impulses for perfect ESP® performance

It is not just in emergency braking that Sensotronic Brake Control proves its worth, but
also in other critical situations – for example, when there is a risk of swerving. Under such
conditions, the system interacts with the Electronic Stability Program (ESP®) which keeps the
vehicle safely on course through precise braking impulses at all wheels and/or by reducing
engine speed. SBC once again offers the benefits of greater dynamics and precision: thanks to
the even faster and more accurate braking impulses from the SBC high-pressure reservoir, ESP®
is able to stabilise early and comfortably a vehicle which is about to break away.

This is evident, for example, from the results of the VDA lane-change test which
suspension engineers use to simulate a quick obstacle-avoidance manoeuvre and to demonstrate
the high capabilities of the Electronic Stability Program. In conjunction with SBC, ESP® works
even more effectively and significantly reduces vehicle swerving through quick and precise
braking impulses.

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At the same time the driver’s steering effort is reduced. Thanks to SBC and ESP® he or
she will have even less difficulty keeping the car on course.

Figure 3.1: DaimlerChrysler AG

With Sensotronic there is no need for ESP intervention when braking in a curve.

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Figure 3.2: Braking in a curve. Left: conventional. Right: with SBC.

Notice the unequal braking force, smaller lateral force, better stability and alignment with
SBC. Orces in a way appropriate to the situation. Hence the system will automatically increase
the brake pressure at the outer wheels because the higher vertical forces also allow them to
transfer greater notice the unequal braking force, smaller lateral force, better stability and
alignment with SBC. Even when braking in corners, SBC also offers more safety than a
conventional brake system.

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CHAPTER-4
BRAKING IN CORNERS

4.1Greater safety thanks to variable brake force distribution:

Even when braking in corners, SBC also offers more safety than a conventional brake
system. This is where the variable and targeted brake force distribution is of particular advantage
to actively influence the car’s compliance steer.

While conventional brake systems always mete out the brake pressure equally to the
inner and outer wheels, SBC offers the possibility of assigning brake forces in a way appropriate
to the situation. Hence the system will automatically increase the brake pressure at the outer
wheels because the higher vertical forces also allow them to transfer greater brake forces. At the
same time the brake forces at the inner wheels are reduced to provide the higher cornering forces
needed to stay on course. The result is a more stable braking behaviour along with optimum
deceleration values.

With the innovative Sensotronic Brake Control Mercedes engineers still stick to the
proven principle of a variable brake force control for the front and rear axles. They program the
system in such a way that, when slowing down from a high speed, the larger part of the brake
force continues to act on the front axle. This prevents a potentially hazardous overbraking of the
rear axle. Again SBC is capable of adapting to the prevailing situation. At low speeds or during
partial braking, the system automatically increases the brake force share at the rear axle to
improve brake system response and achieve even wear and tear of the brake pads.

4.2Comfort: no pedal vibrations during ABS operation

Both the separation of the SBC pedal from the rest of the brake system and the
proportional pressure control using mechatronics serve to increase brake comfort – particularly
during sharp deceleration or when the anti-lock braking system is operational. The usual

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vibration of the brake pedal when ABS sets in does not occur, which, Mercedes engineers have
found, is not only a comfort feature of the new system but also offers measurable safety benefits.
Their research in DaimlerChrysler’s Berlin driving simulator has revealed that almost two thirds
of all drivers are startled when ABS pulsation sets in: they do not increase the brake force further
and are even prone to taking their foot off the brake pedal for a short while, thereby lengthening
the stopping distance of their vehicle – in the driving simulator by an average of 2.10 metres - 7
feet - during ABS braking from 60 km/h - 37 MPH - on a snow-covered road surface.

4.3 SBC add-on functions: support systems to reduce driver strain:

Sensotronic Brake Control offers additional advantages in everyday driving situations –

when slowing down ahead of traffic lights, in the wet, in traffic jams or hill starts:

The so-called Soft-Stop function of the SBC software ensures particularly gentle and
smooth stopping which provides significant comfort benefits particularly around town when you
need to slow down frequently for traffic lights. All this is made possible by the higher-precision
pressure control thanks to mechatronics. On a wet road surface the system metes out short brake
impulses at regular intervals to ensure that the water film on the brake discs dries off and that
SBC can always operate with optimum effectiveness. This automatic dry-braking function is
activated at regular intervals when the car’s windscreen wipers are running. The driver does not
even notice these ultra-precise brake impulses.

The Sensotronic Brake Control also incorporates a so-called Traffic Jam Assist function,
which is activated using the cruise control stalk while the car is stationary. The benefit is that
during stop-and-go traffic drivers only need to use the accelerator pedal; once they take their foot
off the accelerator, SBC slows down the car to standstill at a steady rate of deceleration. The
Traffic Jam Assist facility can remain operational up to 60 km/h - 37 MPH - and switches off
automatically at higher speeds.

On hills or steep drives the Sensotronic Brake Control Drive-Away Assist prevents the
car from rolling backwards or forwards – stepping onto the brake pedal quickly but sharply is all

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it takes to activate the brake. If the driver accelerates, the Drive-Away Assist releases the brake
and allows the car to drive off smoothly.
4.4 The future: SBC paving the way for automatic guidance systems

The advent of electronics in brake technology opens up new and promising opportunities
to Mercedes engineers - and not only in the disciplines of safety and comfort. Thanks to SBC
they have also moved a considerable way closer to the realisation of their long-term objective,
namely to be able to automatically guide the cars of the future along the roads with the aid of
video cameras, proximity radar and advanced telematics. For such autonomous vehicle guidance,
the experts need a computer-controlled brake system which automatically acts on the instructions
of an electronic autopilot and stops the car safely.

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CHAPTER-5
PRESSURE SENSOR

5.1The concept for the pressure sensor:

The major requirements of a pressure sensor for X-by-Wire applications, as previously
mentioned, are high precision and reliability as well as multi functionality and flexibility,
features strongly desired in modern sensor design. These requirements have heavily influenced
the design choices. In order to enhance the precision it has been conceived a silicon micro
machined piezo-resistive pressure sensor chip with two different sensitivities: a higher one in a
low-pressure range (0 to 30 bar), where often an elevated resolution is required, and a lower one
at higher pressures (up to 250 bar). Thus, with one single membrane chip, practically two sensors
are obtained. Moreover, as it will be explained further on more in details, the transition between
the two sensitivity levels determines an area with particularly interesting characteristics that
could be used to recalibrate the sensor from offsets without having to remove it from the system
where it normally operates and mount it on a reference bench. Somehow what could be called a
“self-recalibration” ability. Enhancing the reliability and the therefore the availability of a sensor
needs stability in the components and sensor health monitoring strategies. This latter is possible
through an integrated digital electronic that would hence allow self-test functions. Key point of
these procedures is the previously mentioned recalibration area, which potentially allows
monitoring offsets with a precision up to 0.15 % full scale (FS) without need on integrated
actuators and the relative control electronic. A digital electronic can also be designed, without
major difficulties, to integrate a controller for networking (Controlled Area Network, for
example), consequently enhancing the capabilities and the flexibility of the sensor.

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5.2. Two levels sensitivity and recalibration

The transduction of the physical quantity, pressure in the specific case, into an
electrically measurable figure is performed though piezo-resistive elements implanted on the
surface of the of the silicon chip. This type of transducers is sensitive to the stresses in the two
coordinates defined with respect to the plane where the elements are implanted in the chip (8).
The stresses on the piezo-resistors induce changes in their resistance that can be detected with
rather high accuracy as unbalance of a Wheaston bridge. The stresses on the chip surface depend
on the geometrical characteristics of the latter and on the forces deriving from the applied
pressure (9). Therefore transducers are usually placed in such a way to have maximum response
to the pressure changes and in order to obtain a constant sensitivity. Normally small variations in
the sensitivity are undesirable as they complicate the calibration process and often reduce the
sensor accuracy. On the contrary, in the presented design, a drastical change in the sensitivity as
been conceived through a major variation of the sensor geometry. This characteristic has been
exploited to realize the two sensitivity ranges.

Figure 5.1 Diagram of the sensor chip profile

The sensor consists of a membrane structure at which centre is placed a cylindrical
structure (a centreboss membrane) as shown in fig. 1. As the pressure is applied, from top, the
membrane will move freely downward: this determines a rather sensitive sensor response, which
will continue until 30 bar is reached. At this point the cylinder will enter into contact with the
silicon bulk plate. Consequently the geometrical structure of the sensor will almost instantly
change: the membrane will not be able to move freely any more and will behave more like a ring
fixed at the two sides. The stiffness of the structure will significantly increase, thus the building
up of stresses due to pressure will reduce and thereby the sensitivity will be roughly of a four

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factor smaller than the one between 0 and 30 bar. This determines the low sensitivity range that
is specified up to 250bar. Fig. 2 summarises graphically what has been here above described.

Moreover the cylindrical central structure makes the membrane fairly robust and resistant
to overpressures.

Figure 5.2: Simulated Sensor Response

In silicon the elastic behaviour, opposed to the plastic one, is dominant. Therefore silicon
withstands stresses with almost unchanged characteristics: this is what makes it a good material
for sensors. Thus it can be expected that in the described design the cylindrical central structure
and the respective contact area on the silicon bulk will remain stable. Consequently it can also be
expected that the pressure needed to generate the contact between the two parts will remain
constant through the sensor lifetime, thereby the transition between the two sensitivity levels will
take place always at the same pressure: in fig. this is defined as Recalibration point.

Now, gathering this information together, a contact point is obtained, which is:
mechanically determined, constant and independent from the electrical characteristics of the
transducers. Therefore, if it is possible to evaluate a procedure to determine this point though the
normal sensor operation, than a monitoring and correction of electrical instabilities such as offset
drifts can be achieved without need of a reference sensor or external action: a simple example of
how this could be obtained. Moreover, the recalibration principle makes no use of internal
actuation system, no actuator control or extra technology is therefore needed: the sensor

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integrates what can be called a passive recalibration and self-test principle. Furthermore such
procedure could enable to avoid long and costly temperature calibrations. Least but not last, the
contact or recalibration point is determined through the sensor technology and can be so defined
to be different from sensor to sensor. In the case the sensor is operating in a network
environment where more of these sensors with different contact pressures are present, it is
possible to obtain more recalibration points, potentially increasing the sensor accuracy.

5.3 The integrated digital electronic and the self-test

Digital electronic is often thought to be expensive for pressure sensors. This argument
usually does not consider all the potential advantages that it can bring, either because of the
difficulty to have a complete overview on them or as a rather significant research effort is needed
to be able to exploit them completely. Moreover costs of digital electronic are on the long term
continuously decreasing.

In the presented design it has been chosen to make use of a digital electronic in order to
implement monitoring and correction strategies in the sensor. Activities are being carried out to
investigate all possible failures of the sensor and evaluate their entity, this already at design
level. Hence eliminate through design as much of them as possible, particularly those that
cannot be automatically detected by the sensor. On the remainder will be in the first place
evaluated methods to individuate the errors (self-test) and, when possible, correct them without
the outside intervention (recalibration). A diagram of this procedure is described in fig. 3In the
presented design it has been chosen to make use of a digital electronic in order to implement
monitoring and correction strategies in the sensor. Activities are being carried out to investigate
all possible failures of the sensor and evaluate their entity, this already at design level. Hence
eliminate through design as much of them as possible, particularly those that cannot be
automatically detected by the sensor. On the remainder will be in the first place evaluated
methods to individuate the errors (self-test) and, when possible, correct them without the outside
intervention (recalibration). A diagram of this procedure is described in fig. 3.

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Figure 5.3: Self Test

Furthermore network capabilities can be introduced and thereby user tailored functions
can be programmed resulting in an enhanced sensor flexibility.
Clearly a complex electronic has not only advantages consideration has to be taken not to
introduce further hardware, but also software errors. Central point of the self-test strategies is the
previously described “Recalibration point”. The presence of a digital electronic allows
performing the drift monitoring and the recalibration internally. A simple example might help the
understanding. Lets suppose that the sensor is working in a system where the pressure can rise
linearly, namely 250 bar in 8 sec., for simplicity lets also suppose that the sensor has an ideal
linear behaviour in the 2 sensitivity ranges (in the real case there will be a linearity error which
will ad up to the calculations, on the other hand though the sensor response could be better
described by polynomialls of higher order, therefore it has been chosen to stay with the simplest

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case). During the pressure rise 4 points are sampled through the digital electronic: point one at
sensor output around 0 V and the second around 2 V, in the low pressure range, the third at 2.3 V
and the fourth at 4 V, in the high pressure one as shown in fig. 4 (a wise choice of the points can
influence up to 50% the accuracy with which the recalibration point can be determined). These
points are used to define the 2 lines, which intersection will determine the contact voltage. This
can be compared with the value stored in the sensor memory at the previous recalibration and, if
the difference exceeds the calculation errors, the new value will substitute the old one: the sensor
response lines will be adjusted and thereby a recalibration will take place. Key point of this
procedure is the dimension of the calculation errors. If the linearity error is not considered, for
the reasons previously given, these depend on the sensor A/D converter resolution and the
sampling frequency. Therefore, with a 10 bit A/D converter and sampling at 1 kHz a
recalibration with approximately a 0.15 % accuracy FS can be obtained. To the reader is left the
little mathematic game that takes to the given value.

Figure 5.4: Example of possible calibration procedure

The sensor design
Defining a concept for a new sensor is no trivial job. Putting this into a realisable design
is even more complex and requires a good deal of experience in sensor manufacturing and
simulation techniques. The transducer chip design has been conceived in collaboration between
EADS (European Aerospace
Defence and Space company) Deutschland GmbH and AKTIV SENSOR GmbH, with the
contribution of the Technical University of Berlin. The electronic design instead was the result of
the cooperation of EADS Deutschland GmbH and ELBAU GmbH.

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CHAPTER-6
DESIGN
6.1The chip design

The major difficulty in the design was to realise the change in the mechanical structure in
such a way that the sensor response variation between the two configurations would be possibly
sharp, but most of all that the response with respect to the pressure change would be
monotonous. If this condition is not fulfilled, there is no one to one correspondence between the
transducer response and the applied pressure: there will be different pressures that will produce
the same output signal, thereby the sensor will be intrinsically unreliable and therefore unusable.
Overcoming this problem means that the piezoresistors (the transducing elements) have to see
always increasing stresses with the rising of the pressure. Therefore the choice on the piezo-
resistor position on the chip membrane is determinant and with it the results of the simulation.
The choice that has been made in the positioning of the piezo-resistive elements can be noted
that the stress distribution changes significantly before and after the mechanical contact.
Moreover it has been chosen design 90-degree profiles in order to reduce the previously
described risk: this implies using anisotropy etching. etching. The results of the dry etching
process can be seen in fig. 6.

Figure 6.1: SEM picture

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6.2 The electronic design

The design of the electronic should be maintained to a low level of complexity. Never the less
attention should be given to the design in order to be able to implement all the self-test and
recalibration features allowed by the design, but at the same time avoiding unnecessary over
dimensioning of components that would only reflect itself on an increase of costs. Particular care
should be given in taking advantage of the high resolution in the low-pressure range: for
example, in the case of a linear analogue or Pulse-Width Modulation (PWM) output is desired,
as it normally is in sensor output coding, a high resolution digital to analogue converter is
needed. Moreover, in the design is planned: a volatile memory for storing the calibration
parameters, a non-volatile one for the programming of the self-test and recalibration algorithms,
a PWM module, a CAN module for a bus communication and of course analogue to digital
converter to enable the signal processing. In the first prototype a low level of integration has
been chosen to enable more design flexibility, never the less most of the needed functions could
be performed by a commercially available ASIC which could be integrated in second stage.

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CHAPTER 7
ADVANTAGES AND DISADVANTAGES
Advantages
1. Improves metering of required brake pressure.
2. Maximum pressure available immediately.
3. Electronic Brake Proportioning.
4. No pedal vibration during ABS operation.
5. Dry braking function.

Disadvantages
1. Maintenance is high.
2. Electronic part are costly to replace.

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CHAPTER. 8
CONCLUSION
In simple words we can conclude that the Sensotronic Braking Technology is system of
interdisciplinary interactions of mechanics and electronics which provides its benefits to a
greater extent. The micro-computer, software, sensors, valves and electric pumps together allow
a totally novel, highly dynamic brake management. Considering the disadvantages it is not
correct to conclude that Mercedes will entirely scrap SBC system. It will surely continue to
develop and improve braking system with less prone conditions to malfunctioning

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CHAPTER 9
REFERENCES
[1]. TejasParge, SiddharthKshirsagar,” Sensotronic Brake Control System Accelerating New
Technology” International Journal of Engineering Technology, Management and Applied
Sciences, August 2014, Volume 2 Issue 3, ISSN 2349-4476.
[2]. L.Nagabhushan Reddy ,S.Rajesh,” SENSOTRONIC BRAKE CONTROL”, International
Journal & Magazine of Engineering, Technology, Management And Research, May 2010,ISSN
No: 2320-3706.
[3]. Anton T. van Zanten, Robert Bosch GmbH,” Evolution of Electronic Control Systems for
Improving the Vehicle Dyna

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