Informal document No. GRRF-57-30
(57th GRRF, 31 January-4 February 2005,
agenda item 6.1.)
Status report
Informal Working Group on the Electronic Vehicle
Stability Control
Dr. Laszlo Palkovics
Geneve, February 2, 2005
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Mandate and targets of the Working Group
Mandate of the EVSC Working Group
“
Regarding the consideration of electronically controlled
stability enhancement systems, the Chairman requested the
consent of WP.29 to establish an informal group in order to
investigate that issue in greater detail. WP.29 gave its
consent.”
•
How to understand this mandate?
1. Make a consolidated concept for the future regulation clarifying
the following issues:
1. What to regulate (system, vehicle) – definition of the EVSC
system
2. Where to include (Reg. 13, Reg. 111, separate, etc.)?
3. How to regulate – only technical aspects, no economical or
political aspect are considered.
2. Based on the concept, prepare a text proposal for the
regulation.
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Project plan
Target deadline
Activities
Output
Remarks
November, 2004
1st EVCS meeting
Concept proposal for the
regulation
End of January, 2004
2nd Meeting in
Paris
Finalize the concept, make
agreement
February, 2004
GRRF Meeting
Accept the concept
proposal, comments
April 15, 2004
Working meeting
1
First consolidation of the
text
July, 2004
Working meeting
2
Second consolidation of the
text
September, 2004
GRRF Meeting
Accept text proposal
Preparation to
the February
GRRF meeting
Meeting in
Brussels
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT


Summary of the activities and results
•
•
1st meeting of the ad hoc group (Budapest, November 25-26,
2004). Major activities and achievements:
– Definition of the tasks for the working group
– Text proposal for the future regulation – embedded in Reg. 13.
Basis: draft paper from the European industry work group.
– Identification of potential problem areas – nomination of persons
dealing with those topics
– Over 40 persons participated at the meeting, industry is well
represented
2nd meeting
– Discussion of the identified problem areas
– No conceptual change in the text generated during the first
meeting, refinements at some points. Valuable contribution from
the Russian delegation
– Principal agreement about the structure of the proposal
– More than 30 participants at the meeting, good mixture of
participants (industry, government, technical services)
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
The most important issues
•
Why should we regulate the EVSC systems?
•
How complex should the regulation be?
•
Where the regulation should be embedded?
•
Definition of the EVSC system – no unified definition for power
driven vehicle and trailer.
•
Design requirement (+demonstration of the functionality) vs.
performance requirement.
•
How to demonstrate functionality? Vehicle test and/or
simulation.
•
Warning signal to driver – light vs. audible signal.
•
Compatibility between tractor – semi trailer, or truck – trailer
•
Align activities with the ISO 11992 Working Group
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Why EVSC should be regulated?
•
Increased society demand for enhanced traffic safety, signaled
by facts that
– EVSC is becoming typical in the higher passenger vehicle
classes
– Attempts to mandate it for some special service vehicles
– Local attempts for mandating EVSC systems for buses (either
government initiative, or manufacturers initiative)
•
Different kind of systems are available on the market
(developed, industrialized), which would fulfill the society
demand
•
Legislation has to bridge the society demand with the existing
and future systems in order to provide terms of references
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Why EVSC should be regulated?
•
•
•
Denmark will mandate stability control system for coaches of
class M3 as of 01.05.2005.
This attempt is highly welcome, since the stability control
system significantly contributes to the traffic as well as
passenger safety.
However, there are several problems with the current
formulation:
– Definition of the required stability control system (called ESP in
the document) is not sufficient
– There are no clear requirements defined
– EVSC in class M3 is only available for the heavy coaches (> 10
tons) with electro-pneumatic brake system. The system is not
available for lower category coaches.
– Even in M3 > 10 tons class most of the delivered bus chassis
will not have the stability control system, that must be applied
for this vehicles
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Cornerstones of the future regulations
•
•
•
•
The regulation shall not be very complex, and put a very high
burden on the manufacturers and the Technical Services to
fulfill its requirements, but
It must be comprehensive enough and provide terms of
references in order to exclude the systems not performing on
the expected level
It should appear as soon as possible in order to follow the
demand of the society.
The mandated types must be selected according to their
impact on the traffic safety (most common, high volume
vehicles).
A fair trade-off should be found
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Where to include?
Proposed amendments to ECE Reg.13,
Explanatory Note – not part of proposal: Within the GRRF forum there is still an open
point as to whether specific requirements concerning electronic vehicle stability controls
should be integrated into R13 or R111 – this document has been prepared on the basis
assumption that it will would be part of R13, but implies no recommendation. Reg. 79 to be
considered in the formulation of this amendment of Reg. 13.
•
•
Regulation 13 has been selected, since almost all of the stateof-the-art EVSC systems are using the brake as intervention
actuator
However, where other intervention is possible, this regulation
should comply with the relevant other regulations, such as
Reg. 79 in case of superimposed steering (a footnote has been
created)
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Definition for power driven vehicle
Add a new paragraph 2.28 to read:
2.28 “Vehicle Stability Function” means an electronic control function for a power-driven
vehicle which improves the dynamic stability of the vehicle and shall include a
directional control and may include a roll-over control as defined below:
2.28.1 “Directional control” means a function within a vehicle stability function that assists
the driver in maintaining the vehicle in the direction intended by the driver.
2.28.2 “Roll-over control” means a function within a vehicle stability function that reacts to
the potential of roll-over to stabilise the vehicle or towing vehicle and trailer
combination during dynamic manoeuvres.
Definition of the EVSC system for individual vehicle units
but not for combinations
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Definition for trailer
Add new paragraph 2.29 to read:
2.29
“Trailer Stability Function” means an electronic control function for a trailer which
improves the dynamic stability of the trailer and shall include rollover control and may
include direction control as defined below: that reacts to the potential of roll-over to
stabilise the trailer during dynamic manoeuvres.
2.29.1 “Trailer roll-over control” means a function within a trailer stability function that
reacts to the potential of roll-over to stabilise the trailer during dynamic manoeuvres.
2.29.2 “Trailer directional control” means a function within a trailer stability function that
assists in maintaining the direction of the trailer with that of the towing vehicle.
Separate definition for trailer because of the most complex
dynamics
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Compatibility matrix for multi-unit vehicles
Centre Axle Trailers
IMP
IMP
IMP
IMP
With
YC + RSF
IMP
With
RSF
IMP
With
ABS
IMP
Without
ISO7638
NC
With
YC + RSF
NC
With
RSF
NC 1/
With
ABS
NC
Full (Drawbar) Trailers
Without
ISO7638
NC
With
YC + RSF
With
RSF
Without
ISO7638
With
Tractor ISO7638
With
DC
With
DC + ROC
Without
ISO7638
With
Truck
ABS
With
DC
With
DC + ROC
With
ABS
Towing Vehicle
Without
ISO7638
Semi-Trailers
NC
NC
NC 1/
NC 1/
NC
NC
NC 1/
NC 1/
NC
NC
IMP
IMP
NC
NC
IMP
IMP
IMP 2/
IMP 2/
IMP
IMP 3/
IMP 2/
IMP 2/
IMP 3/
IMP 3/
IMP 2/
IMP 2/
IMP
IMP 3/
IMP 2/
IMP 2/
IMP 3/
IMP 3/
1/: Stability function(s) not functional as the tractor has no ISO7638 power supply is available
2/: Identification problem between centre axle and full trailers as the trailer has no electric control line to identify the
trailer type
3/: It is not clear how the respective truck and trailer systems will interact and how this will impact on combination
stability therefore it may be necessary to define priorities to inhibit either the truck or trailer stability system.
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Design requirement for the intervention
5.2.1.31.1.
Where a vehicle is equipped with a vehicle stability function as defined in
paragraph 2.28 the following shall apply:
In the case of directional control the function shall have the ability to
automatically control individual wheel speeds by selective braking based on
the evaluation of actual vehicle behaviour in comparison with a determination
of vehicle behaviour demanded by the driver. 1/
In the case of roll-over control the function shall have the ability to
automatically control individual or multiple wheel speeds by selective braking
or automatically commanded braking based on the evaluation of actual vehicle
behaviour that may lead to vehicle roll-over. 1/
Brake system based intervention – a clear design
requirement
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Design requirement for the dynamic estimation
5.2.1.31.2.
To realise the functionality defined above a vehicle stability function shall
include, in addition to selective braking and where appropriate automatically
commanded braking, at least the following:


5.2.1.31.3.
The ability to regulate engine power output.
The determination of vehicle behaviour from measured values of yaw
rate, lateral acceleration and wheel speeds and from the driver’s control
input to the braking system, to the steering system, and to the engine.
A vehicle stability function of a different design to that described in paragraph
5.2.1.31.2. above shall be deemed to fulfil the requirements of a vehicle
stability function provided that at least equivalent performance is achievable.
The assessment procedure used shall be agreed between the vehicle
manufacturer and Technical Service to ensure the objectives defined in 2.28.
are fulfilled and shall require comparative testing with a representative vehicle
fulfilling the specification defined in 5.2.1.31.2. above.
Design requirement – derived from state-of-the-art systems
as necessary and sufficient requirement
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Performance requirements?
•
•
The most severe discussion has been induced by the question:
should we define performance requirements?
Difficulties with performance requirements:
– There is no uniquely defined performance level for the EVSC
systems
– Definition of the possible tests is not obvious (all ISO standards
have been analyzed)
– Repeatability of the tests on the stability limit is not possible
– Complex test requirements (similar to those conducted by the
OEs and system manufacturers during the release process) is
hardly possible at the Technical Services, puts additional very
high burden an the system
Conclusion: if there is no obviously defined, realistically
measurable performance requirement – better not to define
anything
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Compromise: “performance demonstration”
5.2.1.31.5
The operation of the vehicle stability control shall be
demonstrated by means of checked by a dynamic test or
alternatively by the submission of test results from a
representative vehicle or from computer simulation 2/. The
method by which this demonstration check is carried out shall
be agreed between the vehicle manufacturer and the
Technical Service and shall include the critical conditions of
under-steer, over-steer and rollover as appropriate to the
vehicle stability function installed on the vehicle with the
method of demonstration assessment and results being
appended to the type approval report.
An acceptable compromise has been found – vehicle
demonstration as well as simulation is possible
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Alignment with the informal ISO 11992 WG
•
•
An informal ISO WG is active in re-considering the ISO 119922003. Activities in the EVSC WG will be aligned
Proposals for several new information transmitted via the
electronic control line. Some of the most relevant ones:
– EVSC active on the truck/trailer
– Request for relative brake demand side and axle-wise on the
trailer
– Geometric data content of the trailer
– Trailer identification data
– Motor vehicle/trailer is/is not equipped with EVSC system
– Disable of complete/partial EVSC function on motor
vehicle/trailer
Input from EVSC WG fits to the schedule of the ISO WG
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Summary of the current status
•
•
•
Generally: the progress in the working group is much higher
as we expected.
A draft version of the text proposal for the EVSC regulation
embedded in Reg.13 is available
The major characteristics are:
– Clear design requirements for the intervening actuators and
sensors, as minimum set
– Demonstration of the functionality during critical maneuvers is
required
– The proposal does not put very high burden an the end user,
manufacturer, but comprehensive enough to give clear terms of
references
– To introduce the regulation in the proposed form as soon as
possible, and re-visit performance demonstration issue in 2
years based on the experience collected by the Technical
Services
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT
Thanks to the participants of the ad hoc
group for their commitment and work what
they provided during last period.
REPUBLIC OF HUNGARY
MINISTRY OF ECONOMY AND TRANSPORT