How do traffic signals detect cars and bikes?

Traffic Loop

Most of the City's traffic signals have a way to detect vehicles and bicycles. Some locations have a loop of wire placed in the roadway that can determine when a vehicle or bicycle is present. Many newer signals have the bicycle detector symbol (small bike symbol) on the loop in the locations where a cyclist is most likely to be detected by a signal.

Video Detection

In a few locations where traffic loops are not feasible, the City has used video detection. The video detection system works by providing an image to a small computer that can detect a change in the image and determine the presence of a vehicle or bicycle.

Video detection can sometimes be compromised by the environment: fog, dust, shadows, trees, headlights and the reflection of the son on the asphalt can all have adverse effects on the accuracy of detection.

Show All Answers

1. Why are traffic signals needed?
2. Who decides which intersections need signals?
3. How do I request a stop sign?
4. How do I get additional street lights placed on my street?
5. How do I report an obvious malfunction with an existing traffic signal?
6. Why doesn't the City place temporary signs at intersections during power outages?
7. How do I get speed bumps installed on my street?
8. People drive too fast on my street, can the City lower the speed limit?
9. People are always speeding on my street, can the City post a stop sign?
10. Where can I park when I visit downtown Woodland?
11. What is the difference between a marked crosswalk and an unmarked crosswalk?
12. Are bushes or shrubbery allowed to obstruct the vision of the driver?
13. How do I get a pothole fixed?
14. How do I get cracked asphalt on my street fixed?
15. When is my street scheduled to be resurfaced?
16. A crew was on my street last year paving, why are you resurfacing it again this year?
17. Why is my street getting resurfaced now it doesn't look that bad really?
18. How do I report a street sign that is knocked down or bent?
19. What can be done about a car parked illegally on my street?
20. My streetlight Is out. What should I do?
21. Why are some streetlights white and some yellowish?
22. How do traffic signals detect cars and bikes?