This report presents the results and lessons learned from field deployments and tests of eight portable and semi-portable traffic detector systems. These tests are the culmination of research conducted to determine suitable, primarily non-intrusive, traffic detectors for use in Hawaii. These tests were conducted at nine freeway and arterial road sites on the islands of Oahu and Hawaii. The systems tested, grouped by how the sensors were installed, are as follows: Underground or underbridge: (1) 3M microloops and Canoga 800 Series detectors; On-ground: (2) Optical Sensor Systems fiber optic sensors and ITC TRS counter/classifier, (3) pneumatic tube sensors and JAMAR TRAX RD counter/classifier, (4) Roadtrax BL piezoelectric sensors and PEEK ADR-2000 counter/classifier, (5) Spectra Research ORADS (NTMS) portable laser sensor and IRD TCC 550 counter/classifier; and Above ground, side-fired: (6) RTMS model X2 and RTC data unit by EIS, (7) SAS-1 acoustic sensor and SAS-CT board by Smartek, and (8) SmartSensor microwave sensor by Wavetronix. Several emerging telecommunications and data retrieval services were installed and tested as part of these systems: TrafInfo's Trafmate satellite modem and digital pager, and TrafficWerks' near-real time data retrieval via cellular subcarrier (CDPD or CDMA modem) and integrated archival system. These were tested against some current telemetry practices such as those using standard Hayes 9600 modems and cellular analog technology and found to be greatly superior. Of the four on-ground sensors capable of providing vehicle classification data (in 13 classes), the Roadtrax BL is the only one judged capable of providing adequate and reliable data. All three side-fired, unintrusive sensors can provide reliable and reasonably accurate volume and speed data if properly installed and calibrated. Adequate offset is needed for near-lane detection. Coverage of lanes adjacent and behind median barriers can be difficult. Whereas the underbridge installation of the 3M microloop sensors revealed a number of limitations, further testing of the Canoga detector cards with some existing in-ground loop systems yielded promising results. Specifically, the remote collection of volume data from a traffic cabinet of an actuated Type 170 controller at a signalized intersection was accomplished with Canoga loop boards, TransHub and TrafInfo digital pager installed in Hilo, Hawaii. The remote collection of near-real time freeway data from a station with a 332 cabinet and a Type 170 controller was accomplished with Canoga detector cards, CDMA modem and service integration including web-based data retrieval by TrafficWerks.

  • Corporate Authors:

    University of Hawaii, Manoa

    Department of Civil and Environmental Engineering, 2540 Dole Street
    Honolulu, HI  United States  96822

    Hawaii Department of Transportation

    869 Punchbowl Street
    Honolulu, HI  United States  96813-5097

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Prevedouros, P D
  • Publication Date: 2004-12-23


  • English

Media Info

  • Features: Appendices; Figures; Photos; Tables;
  • Pagination: 165 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00989231
  • Record Type: Publication
  • Report/Paper Numbers: HWY-T-UH-04-01,, Final Report
  • Contract Numbers: 46518
  • Created Date: Apr 15 2005 12:00AM