**[ATTACHMENT: the proposal]{.underline}**

**QUICK HIGHWAY INCIDENT DETECTION AND**

**INCIDENT WARNING SYSTEMS**

**PROBLEM STATEMENT**

Highway incidents have been a major cause of highway congestions (for
example, up to 75% of delays on freeways caused by incidents), and also
a major source for secondary crashes, due to sudden slowdown or stopped
traffic.

It has been proven in incident management practices that the early
detection, quick response, and warnings to upstream traffic are the most
effective ways to reduce the negative impacts of incidents, such as
delays and secondary crashes.

However, due to the constrains in deployment cost, many existing
incident detection and warning systems, deployed by DOTs and local
traffic agencies, are not effective for early detection and quick
response. Therefore, the performance of the systems has not been
effective on reducing delays and avoiding secondary crashes caused by
incidents.

One of the major reasons of the ineffectiveness is the spacing of the
devices. Normally, detection stations and dynamic warning signs are
placed with the intervals about ¼ to one mile. When an incident occurs,
the existing incident algorithms have to wait until the slow traffic
back up to the adjacent upstream detection stations for determining the
occurrence of the incident. In practice, five to seven minutes on
average are needed to detect an incident, which would cause miles of
backups and long delay. And such slow detection and warning systems
could not prevent secondary crashes.

The reason for having to use such large interval between detection
stations and the dynamic message signs is the high costs of the system
devices and communications. For years, researchers have been making
great efforts to improve the systems performance by creating new
algorithms and fine-tuning the existing incident detection algorithms,
but due to the nature of such large intervals, no algorithms could be
effective.

**PROPOSED RESEARCH**

In this proposal, a new incident detection and warning system is
proposed to address the issues of large spacing between detection
stations. The basic concept is to use [multiple low-cost]{.underline}
detection stations with very small intervals. Also low-cost wireless
communication devices and LED signs can be co-installed with each
detection stations. Since the stations are close to each other, it is
feasible to detect and locate an incident very quickly, and also to use
the LED signs to warn drivers for preventing secondary crashes. Low cost
wireless short range communications can also be established through
relaying from one station to another.

The key feature of the proposed systems is the **[low
cost]{.underline}** of the detectors and LED warning lights. Using these
low cost devices, the total per-mile cost of the proposed incident
detection and warning systems could be lower than the existing incident
detection systems, but the coverage and performance of the new systems
should be much better.

[Introduction of the Proposed System and the Operations]{.underline}

The proposed system uses low-cost speed sensors spacing about 100 ft or
less. The sensors with such small spacing in between could not only
detect the changes in vehicle speeds, but also track each vehicle and
the speed differentials between vehicles. Therefore the system could
quickly figure out incident scenarios and provide warnings to upstream
traffic using LED flashers. In this way, quick incident detection and
warnings for preventing secondary crashes could be well accomplished.

For example, if an incident occurs, the nearby upstream traffic lane
should be detected with very slow or stopped traffic, meanwhile the
nearby downstream traffic lane should be empty. Since the detection
stations are close to each other, the location of the incident could be
easily determined in a matter of seconds. Once the incident is detected
and located, the upstream LED flashers can be turned on automatically to
warn drivers for preventing secondary crashes. In this way, the new
systems can detect and locate an incident much faster than the existing
systems, and also can provide real-time or near real-time warnings that
the existing systems can not provide.

Figure 1 illustrates an example that an incident occurred in a highway
blocking the lanes. The sensors on the roadside posts detected the slow
traffic in upstream lanes, and the empty lanes in downstream lanes. Thus
the location of the incident can determined, and the red flashers are
activated to warn drivers in upstream lanes.

**THE Proposed Research Approach**

SBIR Phase I would have three major tasks

(1) Using a simulation tool to evaluate the effectiveness of the
    systems. This task may involve some human factors studies and
    traffic engineering studies.

(2) Developing a prototype system to demonstrate the concept of
    operations. This task includes some systems development and systems
    integration efforts.

(3) Conducting a demo using an appropriate demo site.

The outcome of phase I would build a foundation for phase II, which will
get more comprehensive testing and build a commercial product.

**Figure 1. CONCEPT OF OPERATIONS**

![](media/image1.jpeg){width="6.0in" height="4.229861111111111in"}

**Technical Feasibility of the Proposed Research**

The technologies used in this research project can be built upon many
existing technologies:

First, the application of roadside flashers can be found in some Europe
countries. Figure 2 is a photo of post flasher application -- the
flashers can be turned on manually by the highway operators when needed,
such as in the situations of heavy fog, highway incidents, road
blockage, etc. The system has been proven very helpful in preventing
crashes.

Second, to use multiple speed sensors in a row, as proposed in this
project, has been found in some SICAS research projects; for example,
PATH program has used 80 mini loops to track vehicles in its research
station in California, and Univ. of MN has used multiple radar units at
intersection approaches in MN to measure the gaps in traffic flow.

Third, the similar operations concept for highway workzone has been
demoed by UMTRI in June, 2006 at Chrysler's proving ground (see the
UMTRI final report to FHWA -- 2006). The demo can be viewed at
<http://www-personal.umich.edu/~jsully/> (visit Play Video2 and Work
Zone Video). It can be seen that when a high-speed vehicle is
approaching stopped vehicles, the LED flashers are activated and
increasing flashing frequency to warn the drivers.

FIGURE 2. EXAMPLE OF ROADSIDE WARNING SIGNS

> ![](media/image2.wmf){width="4.958333333333333in"
> height="3.472916666666667in"}

\[the end\]