"Non-intrusive" sensors are defined as those sensors that can be installed, calibrated and used without disruption to traffic. The most common non-intrusive technologies (NIT) used for traffic detections include: passive or active infrared, magnetic, microwave or radar, ultrasonic, passive acoustic, and video. Other, more recent applications, use infrared technology to classify vehicles by counting each vehicle¿s axles from the side of the road. Since 1994, the Minnesota Department of Transportation (Mn/DOT), the Federal Highway Administration (FHWA) and pooled fund study members have implemented a series of NIT sensor evaluations. The most recent project, completed in 2005, designed, fabricated and field tested a portable non-intrusive traffic detection system. These studies have provided valuable information, benefiting both public and private agencies in selecting appropriate technologies for their own data collection purposes.

The objective of the proposed project is to conduct field tests of the latest generation of non-intrusive traffic sensors. The field tests will assess the capabilities and limitations in detecting traffic under a variety of conditions. Specific test conditions will be driven by the needs of participating state agencies.

This project builds on previous research by providing up-to-date field evaluations of currently available NIT sensors. The project will use a variety of existing infrastructure to conduct a 12-month field evaluation. Much of the testing will take place at the Mn/DOT permanent test site at Penn Avenue and I-394 near downtown Minneapolis. This site has a permanent equipment shelter, overhead gantry, and side fire mounting platforms that facilitate a wide variety of tests. In addition, the portable system, developed in the previous project, provides a platform to conduct short-term tests at a wide variety of other locations. The project is broken into the following six tasks. 1) Identify test scope, goal, and objectives Outline project goals and objectives, and scope of tests. 2) Develop Test Plan Develop a detailed test plan that will guide the test activities; ensuring they meet the identified project goals and objectives. The test plan will provide test procedures that detail how to assess the sensors under various test conditions. The test plan will also present the selected test methodologies and testing scenarios that facilitate the evaluation of sensors¿ performance and capabilities. 3) Sensor Procurement A literature search will be conducted to identify the potential participating vendors based on existing and newly developed NIT technologies. 4) Site Preparation The Mn/DOT NIT test site facilitates both baseline and sensor data collection. These facilities include in-place inductive loops, an automatic data recorder, and communication hardware and software. The existing facilities will be reviewed and upgraded as needed to ensure accurate data collection. 5) Field Testing and Data Acquisition Installation and Field Test Activities 6) Data Analysis and Report Preparation Appropriate statistical measures will be identified and used to quantify the performance of sensors in an assortment conditions. Analyzed data will be summarized into various formats to present in the final report. The following list summarizes some of the conditions that will be analyzed:

Our target is to have 15 agencies participation at $15,000 per partner state, yielding $225,000. A full commitment of the 18 months is required.