1. 1 Vehicles as Mobile Sensing Platforms for Critical Weather Data Briefing for the VII Weather Applications Workshop #1 February 22, 2006 National Center for Atmospheric Research, Boulder, CO Andrew D. Stern Meteorologist Principal Investigators Keith J. Biesecker Electrical Engineer

2. 2 FHWA Task Management James Pol, USDOT, ITS Joint Program Office Paul Pisano, FHWA, Office of Operations, Road Weather Management Road Weather Management Special thanks to Vaishali Shah and Calvin Yeung for assisting with the preparation of this presentation.

3. 3 Task Objectives Foundational work for VII/Clarus on the use of vehicles as weather probes Create a test environment that can provide both routine and on-demand data acquisition Provide a set of statistics to begin a discussion about the usefulness of weather data from vehicles Provide an initial estimate of temperature bias from vehicle sensors

4. 4 Task Timeline

5. 5 Collaboration with NCAR Coordinate with NCAR on research –Provide project plans, sample data sets –Provide all presentations –Coordinate on objectives & methods Participate in NCAR Workshops Provide all data sets and reports at the conclusion of the task

6. 6 Dulles Airport Dulles Toll Road Instrumented Corridor Capital Beltway N

7. 7 Sensors Control Products “Surface Patrol 999J” system –General A non-contact infrared surface temperature sensor (scans pavement as the vehicle passes over it) Independent ambient (air) sensor Dash mounted digital meter Digital interface for system status, configuration, and data collection –Specifications Operating Range: -40F to +200F (surface), -40F to +160F (ambient) Resolution: 0.1F (both) Accuracy: 0.5F for ambient temperatures from 0-120F Shock/Vibration: 50G, 10G on any axis Radio frequency hardened & ambient temperature compensation Sampling frequency: Variable to 0.1 sec –Selection Rationale Recommended: “Laboratory and Field Studies of Pavement Temperature Sensors” by Ron Tabler, The Aurora Consortium, May 25, 2005

8. 8 Sensors (continued) Watchport ® /T –General Ambient temperature sensor Plug and Play USB device designed for environmental monitoring. Application software for centralized device status, control, and data logging –Specifications Operating range: -40F to 185F Resolution: 0.1º C Accuracy: +/- 0.9 F (14F to 185F); +/- 3.6F (-40F to 14F)) Sampling frequency: Variable to 8 sec. –Selection rationale Easy integration with existing laboratory resources Device specifications similar to those used in most automobiles for ambient temperature measurements Easy integration of other Watchport devices (e.g., proximity, distance, acceleration/tilt, relative humidity)

9. 9 Sensors (continued) Vehicle Explorer Scan Tool –Freeware utility being developed to collect diagnostics from OBDII system –RS232 interface for configuration, status, and data collection –Sample frequency: 2 sec –Sampling all (18) parameters available on our three test vehicles Engine coolant temperature Engine revolutions per minute Vehicle speed Intake air temperature (IAT) Onboard Diagnostics II (OBDII): –A 2nd generation emissions diagnostic system required on all 1996 and newer vehicles –Monitors vehicle emissions parameters and stores diagnostic trouble codes.(non-emission related parameters in next generation system - OBDIII) –Hundreds of potential parameters to collect depending on vehicle (year/make/model)

10. 10 Mobile Wireless Laboratory –Custom Ford E-450 cutaway van, high-cube body –Integrated computing, networking, display, and communication systems Various CMRS (1xRTT, EVDO, GPRS, EDGE, iDEN) Various WLAN (802.11a,b/g) Satellite (broadband data, TV) Pre-802.16-2004 (WiMAX) Wireless ad-hoc meshed networking Servers, gateways, development PCs, routers, etc. Multimedia peripherals (e.g., tablets, cameras) Digital and analog A/V; multi-terminal Test & measurement Ford Crown Victoria, Police Interceptor (‘98) –Two vehicles –Computing, networking, and display systems Test Vehicles

11. 11 OBD2 Intake Air Temperature (IAT) Watchport USB Ambient Temperature Sensor @ Air Intake Control Products J999 Ambient Temperature Sensor @ Front Bumper Control Products J999 IR Surface Temperature Sensor @ Front Bumper Watchport USB Ambient Temperature Sensor @ Rear Bumper GPS Receiver Watchport USB Ambient Temperature Sensor @ Front Bumper Sensor Placement: Mobile Lab

12. 12 OBD2 Intake Air Temperature (IAT) Watchport USB Ambient Temperature Sensor @ Air Intake Watchport USB Ambient Temperature Sensor @ Rear Bumper GPS Receiver Watchport USB Ambient Temperature Sensor @ Front Bumper Sensor Placement: Crown Victorias

13. 13 Sensor Maintenance & Calibration Maintenance –Examine sensors prior to each run –Clean all sensors (as needed) Test and calibration (as needed) –Test all sensors for accuracy once per week Ambient –OMEGASCOPE® HH22 Digital Thermometer »Accuracy: 1°F + 0.1% reading »Range: -10 to 1000°F »Resolution: 0.1 Surface –OMEGASCOPE® Handheld Infrared Thermometer »Accuracy: ±1.0 % reading (or 3°F, greater) »Range: -10 to 1000°F »Resolution: 1.0 –Calibrate surface sensor (999J) as needed

14. 14 Data Collection Human Observations (recorded every 60 sec) –Cloud cover Clear, partly cloudy, mostly cloudy, cloudy –Precipitation Occurrence & Intensity None, light, moderate, heavy –Precipitation Type None, drizzle, rain, freezing rain, sleet, snow –Visibility No restriction, light fog, dense fog, rain, ice, snow, road spray –Pavement Condition Dry, wet, slushy, snow covered –Lightning/Thunder (Y/N) –Mixing Winds (Y/N)

15. 15 Data Collection (continued) Schedule –15 November 2005 – 31 March 2006 –Once a day; at least 3 days/week –AM, PM, or mid-day –Special weather events (resources permitting) Drive Method –Platooning –one vehicle following the mobile lab, one flanking to the right (as feasible)

16. 16 Mobile Lab Date 02/16/06 Time: 16:08:26 Location: 38° 56’ 47.25”N, 77 ° 17’ 39.52”W Speed: 55 mph Ambient Temperature - OBD2 (IAT): 70 °F - Air Intake: 69.56 °F - Rear Bumper: 77.62 °F - Front Bumper: 68.75 °F - Front Bumper (999J – GT): 68.6 °F Road Surface Temperature: - Front Bumper (999J): 68.8 °F Car #1 Date 02/16/06 Time: 16:08:26 Location: 38° 56’ 47.05”N, 77 ° 17’ 39.40”W Speed: 55 mph Ambient Temperature - OBD2 (IAT): 68 °F - Air Intake: 69.12 °F - Rear Bumper: 86.75 °F - Front Bumper: 68.62 °F Car #2 Date 02/16/06 Time: 16:08:26 Location: 38° 56’ 46.96”N, 77 ° 17’ 38.32”W Speed: 54 mph Ambient Temperature - OBD2 (IAT): 70 °F - Air Intake: 69.31 °F - Rear Bumper: 82.25 °F - Front Bumper: 69.18 °F Mobile Data Samples: Single Point Fixed Observations IAD ASOS @ 15:52 Air Temp=18.9°C (66°F) DTR Plaza ESS @ 16:08:13 Air Temp= 19.3 °C (66.7 °F) Road Temp= 23.3 °C (73.9 °F)

17. 17 ASOS (KIAD) RWIS/ESS #2Radar(KLWX) & Upper Air Dulles Airport Dulles Toll Road Fixed Observations

18. 18 Fixed Sensors: RWIS/ESS #1

19. 19 Fixed Sensors: RWIS/ESS #1 N

20. 20 Fixed Sensors: RWIS/ESS #3 Non-invasive Surface State Sensing Non-invasive Surface Temperature Sensing

21. 21 Dulles Airport ASOS (KIAD)

22. 22 Dulles Airport ASOS (KIAD) Maintained/calibrated by NWS Open exposure on airfield, in a grassy region Official climate station for temperature Observation augmented by human observer

23. 23 NWS Doppler Radar (KLWX)

24. 24 Road Domain translation to Radar Reference Frame via GIS Major Roads in Metropolitan Washington D.C. NWS Doppler Radar Sterling, VA Route Segment of Interest: Dulles Toll Road

25. 25 Precip Estimates on Road Segments 1 km radar bins. Measure primary (red) and secondary (yellow) to obtain an average radar reflectivity value per bin. Dulles Toll Road extends 21 km (bin 3-24) Reflected Energy (Z) = A (Rainfall Rate (R)) Reflectivity-Rainfall Rate (Z-R) Relationship B

26. 26 Establishing Ground Truth (GT) Use the Control Products 999J as GT Compare GT with: –Fixed Air Temperature Sensors (ASOS & ESS) –OBDII On Board (OEM) Sensors –Watchport Sensors Intake Air Temperature Front Bumper Temperature Rear Bumper Temperature –ESS Pavement Temperature Sensors

27. 27 Temperature Data Time Series (#1) Route StartRoute End Engine Warm Up ASOS=39F ESS=45F Silver Car 1/17/2006

28. 28 Temperature Data Time Series (#2) Route Start Route End Engine Warm Up Blue Car 1/17/06 ASOS=39F ESS=45F

29. 29 What Happens in Heavy Traffic? Blue Car 12/22/06 Video Snapshot Time ASOS=41 ESS=49

30. 30 Average Temperature Statistics Mobile Ground Truth Dulles ASOS

31. 31 Average Variation by Sensor Type

32. 32 Mobile vs. In Situ Temperatures

33. 33 Proposed Data Comparisons Compare Temperature Values Under Different Conditions: –Mixed (windy) versus calm conditions –Readings during rainy conditions –Readings during snowy/icy conditions –Compare changes during radar derived light, moderate or heavy precipitation –Compare during low and high sun angles –Compare during light versus heavy traffic

34. 34 Deliverable Report Report delivered at end of task: 4/15/05 Create hypotheses on mobile temperature sensor biases based on: –Sensor placement (position) –Weather conditions (precipitation, winds) –Traffic conditions –Sun angle (time of day)

35. 35 Contact Information Andy Stern –astern@mitretek.org –703-610-1754 Paul Pisano –Paul.Pisano@fhwa.dot.gov –202-366-1301 James Pol –James.Pol@fhwa.dot.gov –202-366-4374