Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Evaluation of a real-time travel time prediction system in a freeway construction work zone : executive summary.

Filetype[PDF-66.00 KB]


English
Details You May Also Like

Details:

  • Creators:
    Zwahlen, Helmut T.
  • Corporate Creators:
  • Subject/TRT Terms:
  • Resource Type:
    Tech Report
  • Geographical Coverage:
    Ohio
  • Edition:
    Executive summary.
  • Corporate Publisher:
    Ohio. Dept. of Transportation
  • Abstract:
    A real-time travel time prediction system (TIPS) was evaluated in a construction work

    zone. TIPS includes changeable message signs (CMSs) displaying the travel time and

    distance to the end of the work zone to motorists. The travel times displayed by these

    CMSs are computed by an intelligent traffic algorithm and travel-time estimation model

    of the TIPS software, which takes input from microwave radar sensors that detect the

    vehicle traffic on each lane of the freeway. Besides the CMSs and the radar sensors, the

    TIPS system includes the computer and microcontroller computing the travel times,

    220 MHz radios for transmitting data from the sensors to the computer and from the

    computer to the CMSs, and trailers with solar panels and batteries to power the radar

    sensors, CMSs, and radios. The evaluation included an accuracy analysis between the

    predicted and actual recorded travel times and a survey of the motoring public. Three

    crews driving independently of each other in the traffic stream recorded predicted and

    actual travel times at three CMSs to the end of the work zone for 12 hours each day for

    three consecutive days, resulting in 119 trial runs. The data recorder in each crew also

    recorded the license plate numbers of private non-commercial vehicles with Ohio license

    plates. A total of 3177 different license plate numbers were recorded and a questionnaire

    was sent to each one. A total of 660 completed surveys were returned and analyzed.

    Based on the regression analysis of actual times vs. predicted times, the system does on

    the average a reasonable job in predicting the travel times to the end of the work zone.

    About 88% of the actual times recorded for each sign, and for all the signs combined,

    were within a range of ±4 minutes of the predicted time. However, a few differences

    (actual-predicted) as great as 18 minutes were observed. Survey responses indicated that

    the motoring public does perceive a certain inaccuracy in the travel times. However

    almost 97% of surveyed motorists felt that a system to provide real-time travel time

    information in advance of work zones is either outright helpful or maybe helpful. In

    summary we may conclude that the real-time TIPS system represents a definite

    improvement over any static non-real-time display system. It provides in general and

    most of the time useful and relatively accurate travel time predictions to the motoring

    public and appears to be perceived by the motoring public as a helpful addition to a

    freeway construction zone.

  • Format:
    PDF
  • Collection(s):
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at rosap.ntl.bts.gov