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Introduction
| Conclusions | Possible
Next Steps
Introduction
Cooperative intelligent vehicle-highway
systems for driver assistance offer the potential to enhance the effectiveness
of active vehicle safety systems that have entered the marketplace for light
vehicles and heavy commercial vehicles. Currently
on the market are adaptive cruise control (ACC), forward collision warning, side
collision warning, and lane departure warning systems -- all of which rely on
vehicle-based sensors to perceive the surrounding environment and detect
dangerous situations.
These autonomous
vehicle-based safety systems, while generally effective, have limitations based
on the laws of physics -- they can't see around blind curves, for instance.
At the same time, autonomous infrastructure systems can and have been
deployed, which detect hazards in real-time and advise drivers via (typically)
changeable message signs. Such
infrastructure systems suffer from the limitation that they can only influence
drivers who choose to pay attention to them, and even then a safe outcome
depends completely on the driver making appropriate and timely decisions.
Cooperative
intelligent vehicle-highway systems (CIVHS) offer an
improved level of overall functionality by bridging this gap. These systems are cooperative
in that the vehicles can receive information from external sources and respond
appropriately, and vehicles can detect and report hazards to external entities,
for dissemination to other travelers. The
systems are intelligent in that the
ultimate response is determined by algorithms that weigh multiple parameters,
rather than by a pre-programmed set of actions.
Therefore, the term CIVHS does not apply to
telematics or traveler-information services which only provide information to
the driver.
The purpose of study, the first of its kind
as far as is known, is to collect information on the various forms of
cooperative IVHS worldwide, and assess R&D activities, deployment issues,
standards development, and government policies to gain a sense for the future of
such systems.
In this study, based upon feedback to the
interim report (published in January 2001), a strawman set of data that would
flow to/from vehicles in CIVHS systems has been defined. This preliminary listing consists of 59 parameters in the
following categories:
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Obstacle in Projected Path of Vehicle
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Speed Advice
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Gap Advice
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Environmental Condition
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Road Condition
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Road Geometry
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Road Use Status
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Automated Vehicle Operation
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Traffic Control Devices
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Messages from Host Vehicle
Examples are items such as the presence and
location of obstacles around blind curves, lane-by-lane speed designations,
reversible lane status, and adjacent vehicle parameters for vehicle-vehicle
communication. An assessment of
feasibility, deployment timeframe, and degree of usefulness for each function is
also provided.
The material provided in this report is the
result of information gathering and contacts with experts and policy-makers in
government, the private sector, and academia.
Conclusions
The report concludes that a fairly robust
international consensus is forming, in that it is generally useful to
communicate external factors to vehicle systems.
There is wide opposition to mandatory enforcement of speed, even while
speed advisories are seen as potentially useful. And, while many agree to the usefulness of CIVHS in concept,
there is wide variation as to levels of investment and sense of deployment
timing.
Looking globally, the Japanese are leading
in testing and deployment of CIVHS for crash countermeasures, while the
Europeans have the strongest focus on Intelligent Speed Adaptation. Work on intersection collision countermeasures dominates
CIVHS work in the US.
In many cases, discussion of CIVHS becomes
"sidetracked" by concerns about
Intelligent Speed Adaptation, which is only a subset of CIVHS.
While the political and user issues rage, it is important to note that
there is significant technical overlap between these systems that can be
productively exploited.
Similarly, CIVHS discussions become
sidetracked with an assumption that extensive deployment of infrastructure
sensing is a necessary component of such systems.
The many complexities of infrastructure sensing and communications
represent a huge challenge for many (but not all) countries.
Because the alternative exists of data provided by floating car
approaches, consideration of CIVHS can productively proceed without
"solving" the infrastructure deployment issue, leaving this to
individual agencies to decide.
A key conclusion is that infrastructure
agencies must lead in CIVHS development, because it is necessary for them to
implement cooperative systems in order to fulfill their mission of providing
mobility and safety. Contrastingly,
the key goal for vehicle manufacturers is to sell cars, which they can do
without cooperative systems, and they can also deliver substantial levels of
safety (which sells cars) without cooperative systems.
Therefore, this process has to be led by the infrastructure side, with
essential support provided on the vehicle side.
Possible
Next Steps
As evidenced by the Parameters Table, the
"first cut" at a total list of likely parameters passing to/from cars
can be defined now, and international consensus can be made on this.
Such a process would assist vehicle manufacturers, highway operators, and
wireless providers in preparing for the CIVHS era. Since CIVHS functions span
both short-term and long-term applications, the initial parameters list should
be developed informally and at a high level.
From the total list, a subset of these parameters can be selected for
near-term systems, with more focused and formal efforts proceeding on these
applications.
It would be very useful to sponsor an
international meeting on CIVHS, addressing the areas addressed in the this
report -- which applications are seen as most useful, which deployment
mechanisms are most promising, which parameters should be standardized, and how
to proceed with development and testing. The
interest is clearly there, and such an initiative may enable those on the
sidelines to get into the game, while allowing consensus to strengthen among the
leaders.
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