Evaluation of Sensys Wireless Detection System: Year-After Evaluation and Off-Center Sensors

Medina, Juan; Benekohal, Rahim F.; Hajbabaie, Ali

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https://hdl.handle.net/2142/45834 Copy

Description

Title

Evaluation of Sensys Wireless Detection System: Year-After Evaluation and Off-Center Sensors

Author(s)

• Medina, Juan
• Benekohal, Rahim F.
• Hajbabaie, Ali

Issue Date

2011-06

Keyword(s)

• Sensys wireless system
• signalized intersection
• magnetometer detector
• rail highway crossing
• inductive loop
• sensor relocation

Abstract

This is the third and final report of the evaluation of the Sensys wireless vehicle detection system at a signalized intersection and a railroad grade crossing. It presents the system performance after one year of its initial installation, and when additional off-center sensors were installed at the stop bar zones of the signalized intersection. Results from the signalized intersection showed no significant changes one year after the system was in use, except for a decrease in the frequency of false calls due to vehicles in adjacent lanes (from a range of 5.6%-7.6%, to a range of 0.8%-2.4%). At the stop bar zones, multiple calls generated by a single vehicle remained similar (between 7% and 10.2%), and no missed, stuck-on, or dropped calls were found. Also, the detection performance at the advance zones did not change. Missed vehicles ranged between 0.6% and 6.1%, most of which were traveling between lanes, and false calls were lower than 2%. At the railroad grade crossing, the performance of the Sensys system after one year did not show significant changes. Stuck-on calls due to trains were rare and occurred at a rate of about one occurrence for every 150 trains. False calls in the left-turn lane due to vehicles in the opposite direction remained high (more than 30%, caused by trucks and smaller vehicles), and missed calls were lower than 1%. The installation of sensors off-center relative to the loop detectors at the stop bar zones of the signalized intersection (close to the leading edge of the loops), resulted in lower number of multiple calls from a single vehicle (from 7%-10.2% down to 2%-3.3%). However, it did not improve on the frequency of false calls due to vehicles in the adjacent lanes.

Series/Report Name or Number

FHWA-ICT-11-083

ISSN

0197-9191

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/45834

Sponsor(s)/Grant Number(s)

Illinois Department of Transportation ICT R27-58

Copyright and License Information

No restrictions. This document is available to the public through the National Technical Information Service, Springfield, Virginia 22161

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