Minnesota Guidestar Evaluation of Non-Intrusive Technologies for Traffic Detection Farideh Amiri Minnesota Department of Transportation Traffic Records Forum
Minnesota Guidestar Presentation Outline Background Test Site Test Methodology Vendors and Technologies Test Results - Qualitative Issues -Preliminary Field Results Future Test Activities
Minnesota Guidestar Easily deployed without disruption of traffic flow Safer for staff to deploy Sidefire, Overhead, under Pavement or Under Bridge Mounting Definition of Non-Intrusive Technologies
Minnesota Guidestar FHWA & Mn/DOT sponsored test of NIT: –Hughes Test: –NIT Phase I: 1995 – 1997 –Report is available at: Success of initial test led FHWA to fund Phase II –Permanent Test Facility Bicycle and Pedestrian Test Background
Minnesota Guidestar Evaluate full capabilities and limitations of devices Test in varying weather and traffic conditions Test in varying mounting conditions (overhead/sidefire, heights, offsets) Historical and Real-time/ITS applications Test Goals
Minnesota Guidestar Standard Test Methodology Develop standard test procedures –Makes results useful to national audience –Makes tests repeatable by other agencies –Reduce amount of duplicate testing –Coordinate with other standards (ASTM) Develop standard statistical procedures –Make results easy to interpret Develop standard report guidelines
Minnesota Guidestar Test Site - Freeway I-394 at Penn Avenue –Free flow to heavy congestion –Inductive loops in place –Three mainline lanes –Two reversible HOV lanes –Catwalk and adjustable mounting poles –Crank-up pole for “side fire” devices
Minnesota Guidestar NIT Shelter - Outside
Minnesota Guidestar NIT Shelter - Inside
Minnesota Guidestar Sidefire Tower
Minnesota Guidestar Overhead Mounting Structure
Minnesota Guidestar Test Site - Intersection I-394 at Penn Avenue –Multiple lane and single lane approaches –Congested in peak periods –Inductive loops in place –Utilize existing poles
Minnesota Guidestar Intersection Site
Minnesota Guidestar Test Methodology Volume, speed, occupancy, presence, classification Compare to baseline Different test conditions –Mounting location (height and offset) –Traffic levels –Time of the day –Different weather
Minnesota Guidestar Participating Vendors and Technology Group Schwartz Electro-Optics (active infrared) 3M (magnetic) ECM (microwave) SmarTek (passive acoustic) Image Sensing Systems (video) Traficon (video)
Minnesota Guidestar Participating Vendors and Technology Group (cont) Novax (ultrasonic) ASIM – Passive Infrared – Passive Infrared/ Ultrasonic – Passive Infrared/Ultrasonic/Microwave
Minnesota Guidestar ASIM, Schwartz
Minnesota Guidestar Video Detectors
Minnesota Guidestar Vendor Considerations –International vs. National vs. Local Presence –Level of Support Provided Wholesaler Only Integration Support –Support track record History with large deployments? Responsive to customer needs? How long in market? References available?
Minnesota Guidestar Vendor Support Schwartz 3M ECM SmarTek Autoscope Traficon Novax ASIM
Minnesota Guidestar Ease of Installation/Calibration Schwartz 3M ECM SmarTek Autoscope Traficon NovaxN/A ASIM
Minnesota Guidestar Baseline Results Manual count of videotape for groundtruth –4-hours of tape (am peak, midday, pm peak, evening) –Count tape multiple times Freeway results indicate absolute error of less than 2 percent Intersection results mixed
Minnesota Guidestar Freeway Baseline
Minnesota Guidestar Overview Results - Freeway SensorMounting No. of Lane Freeway VolumeSpeed ASIM – Passive IROH/SF12%11% ASIM – Passive IR/ UltOH/SF19%- ASIM – IR/Radar/ UltOH13%4% Schwartz - Active IROH11%6% Autoscope – VideoOH/SF31 - 2%1 - 3% Traficon – VideoOH/SF32 - 4%4 - 8% SmarTek – P. AcousticSF %6 - 8% 3M - MahneticUnder32 – 3%2 - 6%
Minnesota Guidestar Overview Results - Intersection SensorMounting No. of Lane Intersection VolumePresence ASIM – Passive IR/ UltSF1-0% Autoscope – VideoOH119%0% Traficon – VideoOH112%0 – 20% SmarTek – P. AcousticSF1-0%
Minnesota Guidestar Mounting Impact on Sensor Performance Two sensors tested at all mounting heights 3 Bases, 5 Heights, 3 Lanes Results Presentation Base vs. height and lane Lane vs. height and base Height vs. base and lane
Minnesota Guidestar Field Test Results Video performs better when: –Higher –Closer to freeway Passive Acoustic performs better when: –45-degree angle between traffic and sensor
Minnesota Guidestar Preliminary Results (Con.) Each Lane: Performance vs. height and base
Minnesota Guidestar -Lane occupancy -Speed -Presence -Vehicle classification (length and height) ITS Applications Real-time Data
Minnesota Guidestar Real-time Data Vehicle-by-vehicle data recorded by data acquisition system: –Occupied time –Speed
Minnesota Guidestar Occupied Time Loop ALoop B 16’ Travel Time Loop Detection Schematic
Minnesota Guidestar Loop 1 Occupied Time Check
Minnesota Guidestar Phase I Results Review (Weather) Most devices performed well in varying weather conditions Video devices affected by wind and lighting conditions Active infrared device affected by rain and snow. Wet pavement caused over counting. Snow caused poor vehicle tracking Passive acoustic device affected by low temperature (Undercounting along freeway, over counting at intersection Passive magnetic device affected by low temperature
Minnesota Guidestar General Results Most devices suited to temporary applications Performance varies little from technology to technology Heavy traffic had some impact at freeway Intersection counting not as accurate Factors to consider –Ease of installation,calibration and maintenance –Mounting flexibility –Power supply needs –Amount of vendor support
Minnesota Guidestar Heavy Traffic Impact Example
Minnesota Guidestar Next Test: Bike/Ped Detection Developed Test Plan –Literature Review –Detection Applications Curbside/Crosswalk Ped Detection (Intersection) Intersection Bicycle Approach Historical Data (Trail) –Parameters: presence, volume, speed, direction
Minnesota Guidestar Pedestrian Detection
Minnesota Guidestar Pedestrian Detection
Minnesota Guidestar PNIT Pooled fund study “Portable Non-Intrusive Technologies” Schedule –Administration, Now –Research, January 2003 –Design and fabrication, April 2003 –Field evaluation, Summer 2003 –Report, December 2003 –Present Results at NATMEC conference, May 2004
Minnesota Guidestar PNIT Goals are: –Research existing portable systems –Build on current design to design and fabricate a new PNIT –Prepare detailed PNIT system design and cost documentation – Evaluate PNIT system in the field under a verity of test conditions –Disseminate results
Minnesota Guidestar Rapid Deployment
Minnesota Guidestar Unique Applications
Minnesota Guidestar For more information projects.dot.state.mn.us/nit Thank you