solutions & innovations · source: iso 26262-3:2011 | table 4 s 3 controllability class...
TRANSCRIPT
THE STEERING SYSTEMMORE THAN JUST COMPONENTS
SOLUTIONS & INNOVATIONS FOR COMMERCIAL VEHICLES
ASIL D
Safety Steering
Computer
Axle Integrated
Safety Angle
Transducer
Each vehicle is different, even if there are only small differences
in vehicle geometry. Our EHLA® steering systems are sufficiently
flexible for this. They can be adjusted via parameters to different
geometries.
When designing your auxiliary steering system we
rely on established standard components which
have already been used in mass production.
REGARDLESS WHETHER MASS PRODUCTION OR A SINGLE VEHICLE, WE ARE THE RIGHT PARTNERS FOR YOU!
GLOBAL MARKET LEADER FOR ELECTROHYDRAULIC AUXILIARY STEERING SYSTEMS EHLA®
ELECTRICALLY POWERED HYDRAULIC POWER PACK
ENERGY-SAVINGThe motor is only supplied with power during active steering.
When driving straight ahead for a long time almost no energy is
consumed. The fuel saving is around 0.5 l/100 km. This energy-
saving concept is also ideal for electric and hybrid vehicles.
INDEPENDENCEThe steering system is completely independent of the vehicle‘s
engine with the hydraulic power pack, since no mechanical power
take-off (PTO) is required. That is why the auxiliary steering sys-
tem can be installed in almost every vehicle, regardless of the
manufacturer.
POWERFULThe Hydraulic Power Pack indeed does justice to its name. An axle
loaded with 12 metric tons can be steered in standstill from the left
stop to the right stop in less than four seconds.
INTELLIGENTThe Hydraulic Power Pack communicates via CAN bus with the
safety steering computer. Thus the direction of rotation of the en-
gine, the speed and the engine status of the Hydraulic Power
Pack and with it the movement of the auxiliary steering axle are
monitored and controlled.
EASY INSTALLATION AND ADAPTIONThanks to the integrated hydraulic block the Hydraulic Power
Pack is directly connected to the steering cylinder which means
less piping and less installation time. Furthermore less cable is
required since no proportional valves have to be actuated. The
Hydraulic Power Pack can be installed where space is available.
HIGH SAFETY LEVELAlso with the Hydraulic Power Pack important functions of the
auxiliary steering system can be realised with safety level ASIL D.
PLUG-AND-PLAY (OPTIONAL)Optionally you can get a completely wired stainless steel box, in
which a safety steering computer, the hydraulic tank and the
Hydraulic Power Pack are already installed. The connectors and
hydraulic connections are located at the outside, so that a real
plug and play solution is available.
Hydraulic
Power Pack
ASIL DNEW
Safety Angle
Transducer
Safety Steering
Computer
Axle Integrated
Safety Angle
Transducer
EXAMPLES OF STEERING MODES
GLOBAL MARKET LEADER FOR ELECTRO HYDRAULIC AUXILIARY STEERING SYSTEMS EHLA®
left right menu
manual
1
2 3 4 5
6
EHU – Electronic rear swing-out suppression
ON ROAD
Steering mode All-wheel steering
Steering mode Crab steering
Steering mode Manual e.g. via T-handle
Steering mode Manual via buttons
1
2
3
4
5
6
We offer a big variety of different EHLA® auxiliary steering systems. The number of axles does not matter at all.
When driving through narrow passages the swing-out of the
vehicle‘s rear is suppressed by shifting the steering line.
The self-tracking pusher axle or tag axle is often equipped with
lifting function and pneumatic suspension. In order not to exceed
the permissible axle loads of the rigid axles, the lift axle is used
to accommodate additional axle loads. Our automatic axle load
distribution system can be used here.
This option is particularly interesting if the vehicle chassis is ex-
tended by a lifted pusher axle or tag axle.
AUTOMATIC REAR SWING-OUT SUPPRESSION
AUTOMATIC AXLE LOAD DISTRIBUTION
SOME FEATURESMAXIMUM MANOEUVRABILITY AND HIGH DRIVING STABILITY ARE BY NO MEANS CONTRADICTORY
The steering system is designed as dynamically as you need it.
Maximum manoeuvrability is required for slow speeds and large
steering angles are possible. For higher speeds the steering
angle is reduced to guarantee high directional stability. These
values can be set by parameters.
THE RIGHT EHLA® SYSTEM FOR EACH VEHICLE
ELECTRICALLY POWERED HYDRAULIC POWER PACK
ENERGY-SAVINGThe motor is only supplied with power during active steering.
When driving straight ahead for a long time almost no energy is
consumed. The fuel saving is around 0.5 l/100 km. This energy-
saving concept is also ideal for electric and hybrid vehicles.
INDEPENDENCEThe steering system is completely independent of the vehicle‘s
engine with the hydraulic power pack, since no mechanical power
take-off (PTO) is required. That is why the auxiliary steering sys-
tem can be installed in almost every vehicle, regardless of the
manufacturer.
POWERFULThe Hydraulic Power Pack indeed does justice to its name. An axle
loaded with 12 metric tons can be steered in standstill from the left
stop to the right stop in less than four seconds.
INTELLIGENTThe Hydraulic Power Pack communicates via CAN bus with the
safety steering computer. Thus the direction of rotation of the en-
gine, the speed and the engine status of the Hydraulic Power
Pack and with it the movement of the auxiliary steering axle are
monitored and controlled.
EASY INSTALLATION AND ADAPTIONThanks to the integrated hydraulic block the Hydraulic Power
Pack is directly connected to the steering cylinder which means
less piping and less installation time. Furthermore less cable is
required since no proportional valves have to be actuated. The
Hydraulic Power Pack can be installed where space is available.
HIGH SAFETY LEVELAlso with the Hydraulic Power Pack important functions of the
auxiliary steering system can be realised with safety level ASIL D.
PLUG-AND-PLAY (OPTIONAL)Optionally you can get a completely wired stainless steel box, in
which a safety steering computer, the hydraulic tank and the
Hydraulic Power Pack are already installed. The connectors and
hydraulic connections are located at the outside, so that a real
plug and play solution is available.
Hydraulic
Power Pack
ASIL D NEW
Safety Angle
Transducer
4–7 System Design
6–6 Specification of software safety
requirements
6–8 Software unit design and implementation
4–8 Item integration and testing
6–7 Software architectural design
6–10 Software integration and
testing
6–11 Verification of software safety
requirements
6–9 Software unit testing
Item testing
Test phase verification
Software testing
Test phaseverification
Software testing
Test phaseverification
Design phaseverification
Design phaseverification
Design phaseverification
Softwaretesting
Test phaseverification
Test
pha
ses
Design phases
Scop
e of
Par
t 6
Scop
e of
Par
t 4
Scope of Part 4
Scope of Part 6
6–5
Initi
atio
n of
pro
duct
dev
elop
men
t at t
he s
oftw
are
leve
l
The processes required for it were already implemented in the
company a few years ago. The result is an ISO 26262-compliant
development process for our electronic components. At the same
time, we remain flexible enough to fulfill individual customer re-
quirements.
This interactive software tool has been developed by us and
matched to the requirements of our customers. PCSnext sup-
ports you during commissioning, maintenance and diagnostics of
the EHLA® auxiliary steering systems. It is designed for develop-
ment and commissioning staff, service experts and for the End-
of-Line-process.
Benefits
➞This user-oriented service tool can be installed on any laptop
and connected with the safety steering computer.
➞Manufacturers of vehicles and automobile repair shops can do
their software updates, diagnostics and parameter settings at
the EHLA® steering system.
➞An external access via TeamViewer is possible.
For simple diagnostic functions the free-of-charge tool
PCSnextLite is available.
UDS (Unified Diagnostic Services) has become established for
the vehicle diagnostics in mass production of commercial ve-
hicles. This interface was implemented by MOBIL ELEKTRONIK
according to ISO 14229 and the safety steering computer can
optionally be prepared for UDS.
Benefits
➞The EHLA® auxiliary steering system can be processed in the
manufacturer‘s diagnostics system of the vehicle without any
additional software.
➞A comprehensive diagnostics of the EHLA® auxiliary steering
system is possible via UDS, so that also I/O‘s can be read and
controlled.
➞End-of-Line Process: The axle alignment or the End-of-Line
parameterisation of the EHLA® auxiliary steering system can
also be done via UDS.
The task of the vehicle manufacturer is to carry out the hazard
analysis and risk assessment. This results in the safety require-
ments for the auxiliary steering system. With the latest generation
of safety steering computers from MOBIL ELEKTRONIK, safety
functions up to ASIL D can be implemented.
ISO 26262 – ALREADY IMPLEMENTED TODAY AT MOBIL ELEKTRONIK
DATA EXCHANGE WITH EXTERNAL SYSTEMS AND SYSTEM DIAGNOSTICS
PCSnext TOOL FOR SERVICE AND DIAGNOSTICS
UDS (UNIFIED DIAGNOSTIC SERVICES)
HIGHEST SAFETY LEVEL ASIL D
C1 C2 C3
E1 QM QM QM
E2 QM QM QM
E3 QM QM ASIL A
E4 QM ASIL A ASIL B
E1 QM QM QM
E2 QM QM ASIL A
E3 QM ASIL A ASIL B
E4 ASIL A ASIL B ASIL C
E1 QM QM ASIL A
E2 QM ASIL A ASIL B
E3 ASIL A ASIL B ASIL C
E4 ASIL B ASIL C ASIL D
Source: ISO 26262-3:2011 | Table 4
S 3
Controllability classSeverity class Probability class
S 1
S 2
The new ISO 26262 requirements often
present great challenges for our customers.
We gladly assist you with our know-how in
this area and more than 45 years of expe-
rience in the design of auxiliary steering
systems.
Ask us for a workshop regarding the topics
Functional Safety / HARA / Safety Concept.
FUNCTIONAL SAFETY
Safety Steering
Computer
Axle Integrated
Safety Angle
Transducer
EHLA® STANDARD FOR COACHES – OPTIMISED FOR YOU
Coach buses are equipped with a steered rear axle. For this
application our EHLA® STANDARD has proven since years. This
auxiliary steering system has also been further optimised for you.
With the latest generation of safety steering computers from
MOBIL ELEKTRONIK, safety functions up to ASIL D can be im-
plemented.
If the vehicle is equipped with an ESP system, the safety steering
computer can access the steering wheel angle via CAN bus. This
means that no safety angle transducer is required for the front
axle. This saves assembly time and reduces the number of com-
ponents.
THERE ARE ALSO VARIOUS POSSIBILITIES OF APPLICATION FOR BUSES
MORE THAN JUST A HIGHLIGHT – THE SYSTEMS HAVE PROVEN THEMSELVES THOUSANDS OF TIMES
MULTI-ARTICULATED BUS
For these complex vehicles the steering of multiple rear axles is
realised by using EHLA® FAILOP. The articulation angle is also
monitored and taken into account by the EHLA® auxiliary steering
system. This auxiliary steering system achieves the highest
safety levels.
BUS STOP AUTOMATIC
A LOT OF SPECIAL FEATURES AVAILABLE:
DOOR COLLISION PROTECTION
When the doors are opened, the system automatically switches
to bus stop mode. After closing the doors and continuing driving,
the rear swing-out suppression is activated in order not to endanger
waiting pedestrians with the rear of the vehicle.
This feature is important, if the back doors of the bus are assem-
bled very close to the steered rear axle. Before opening the doors,
the steering axle is set straight to avoid a collision between door
and axle.
ARTICULATED BUS
The articulation protection of the joint is realised with a safety
steering computer by MOBIL ELEKTRONIK for this buses.
With the latest generation of safety steering computers from
MOBIL ELEKTRONIK, safety functions up to ASIL D can also be
implemented for articulation protection. Integration into the vehicle
control system is possible via CAN bus.
© MAN Truck & Bus AG
Safety Angle
Transducer
ProportionalHydraulic Unit
ASIL D
LENKUNGSteer-by-Wire ARBEITSFUNKTION
Control-by-Wire
FAHRANTRIEBDrive-by-Wire
BREMSEBrake-by-Wire
MOBIL ELEKTRONIK GMBH
Bössingerstraße 33 . D-74243 Langenbeutingen
Phone +49-7946-9194-0 . www.mobil-elektronik.com
ABOUT MOBIL ELEKTRONIK
Introducing the first steer-by-wire systems for heavy duty vehicles
MOBIL ELEKTRONIK has taken a pioneering role in system techno-
logy for mobile automation since 1973. Because a safe and reliable
system is more than the sum of its individual components we
strengthen our core competences safety technology and systems
engineering continuously. This development led to numerous inno-
vative and groundbreaking solutions and we are proud to have
substantially filled terms like steer-by-wire und control-by-wire
with meaning.
What started as a small engineering office has developed into an
internationally active company with more than 110 highly motivated
employees. Our complete systems can be found in all areas of
commercial and special-purpose vehicle construction today. © M
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OVERVIEW OF EHLA® SYSTEMS
Auxiliary steering system for self-tracking
tag axles and pusher axles
Auxiliary steering system for locking axles
Auxiliary steering system for driven,
steered rear axles with centering device
Auxiliary steering system for multiple
steered rear axles
Redundant fail-operational auxiliary
steering system
Auxiliary steering system for 2-, 3- or 4-axle
agricultural trailers
Auxiliary steering system with independent
hydraulic supply for semitrailers
Auxiliary steering system with independent
hydraulic supply