Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners
-
Upload
joelle-gomez -
Category
Documents
-
view
29 -
download
1
description
Transcript of Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners
![Page 1: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/1.jpg)
Bicycle Detection Using Caltrans Type D Loops:More Options for Practitioners
Presented toITE District 6 Annual Meeting
June 24-27, 2012by John Kerenyi, P.E., Senior Engineer,
City of Moreno Valley
![Page 2: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/2.jpg)
Summary of Presentation
• California AB1581• Caltrans recommendations• Desired configurations/deviation from
Caltrans recommendations• ILD theory of operation• Type D loop field measurements• Calculations/recommendations
![Page 3: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/3.jpg)
California AB1581
At new or substantially modified intersections (>50% of detection replaced), re: detection:“To the extent feasible and in conformance with professional traffic engineering practice, to be installed and maintained so as to detect lawful bicycle or motorcycle traffic on the roadway.”AB1581 became effective in 2010
![Page 4: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/4.jpg)
Caltrans Guidance—Requirements• Reference rider described
– 4 ft tall– 90 lbs min– 16” aluminum wheels, non-ferromagnetic frame
• Reference rider described in a manner suitable for testing detection by many means e.g. ILD, video, microwave
• Either detect reference rider, or place approach on recall (semiactuated/pretimed operation allowed)
• Bike pushbuttons not enough anymore• Bike min green timing recommended
![Page 5: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/5.jpg)
Caltrans Type D Loop
![Page 6: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/6.jpg)
Type D Loop Variations
City of Moreno Valley
City of Los Angeles
![Page 7: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/7.jpg)
Caltrans’ Type D Loop Recommendations
• Wire in series with three other standard (e.g. round or octagonal) loops which are connected in parallel to each other
• Wire in series with two other standard loops• Wire to own detector card channel
Detector Card
D
E E
Detector Card
D
E EEDetector
CardD
![Page 8: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/8.jpg)
Desired Configurations
E D
E D
E D
E DE E
Case 1:Two loops in one lane
Case 3:Four loops in two lanes
Case 2:Four loops in one lane
![Page 9: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/9.jpg)
ILD Theory of Operation
![Page 10: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/10.jpg)
Sensitivity
![Page 11: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/11.jpg)
Series or parallel?E D
E
DDcircuit
L
LSS
1
1
Parallel wiring
D
EDcircuit
LL
SS
1
1
Series wiring
DDetector
Card E
DDetector
Card
E
Seek to minimize
LD = 190 μH
LE = 60 μH(Three Turns)
(Five Turns)
Scircuit = 0.76 SD Scircuit = 0.24 SD
Sensitivityfactor
Case 1
L
LS
![Page 12: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/12.jpg)
Case 2E DE E
E
DDcircuit
L
LSS
1
1
D
EDcircuit
LL
SS
1
1
Parallel wiring Series wiring
Maximize
Minimize
SD minimized by placing the Type E loops in series
SD minimized by placing the Type E loops in parallel
E
E
E
DDetector
Card
D
Detector Card
E E E
SF: 0.61(4 turns)
SF: 0.51(3 turns)
![Page 13: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/13.jpg)
Case 3E D
E D
E
DD
Detector Card
EE
DDetector
Card
E
E
D
D
Detector Card
E
D
E
DDetector
CardE
D
Configuration 1 Configuration 2
Configuration 3 Configuration 4
SF: 0.33 SF: 0.17
SF: 0.26 SF: 0.17
![Page 14: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/14.jpg)
Discrimination ofBicycles and Vehicles
• Desirable to avoid timing long minimum greens every cycle for occasional bicycles
• Known efforts– OCTEC ILD method
– Microwave: Intersector, others– Video detection manufacturers
![Page 15: Bicycle Detection Using Caltrans Type D Loops: More Options for Practitioners](https://reader038.fdocuments.net/reader038/viewer/2022110101/56812b7e550346895d8f9b55/html5/thumbnails/15.jpg)
Recommendations• Case 1 (two loops): Parallel
• Case 2 (one D and three E): Parallel/series (opposite ofCaltrans recommendation)
• Case 3
• Further research is necessary esp. for splashover
DDetector
Card E
E
E
E
DDetector
Card
E
DD
Detector Card
E