Ann Arbor Weather:
Wednesday December 19, 2018
Follow us: facebook twitter RSS feed

Orange Discs in the Road

Question Corner: May 2018

by Tim Athan

From the May, 2018 issue

Q. We are noticing orange discs embedded in some Ann Arbor roads. Their location suggests traffic light management; however many are located after the intersection, leading me to think they are not changing the light for that intersection. What are they doing?

A. The discs are battery-powered sensors used for an adaptive traffic management system. "The sensors are placed on the departure side of intersections so they can gauge the amount of traffic flowing to the next intersection and therefore inform our traffic signal system," reports city spokesperson Robert Kellar. "They are connected to our traffic control systems using wireless technology."

According to a 2017 article in Wired magazine, Ann Arbor's system uses data from the discs and from roadway camera systems to adjust the timing of multiple stoplights. A bulletin from manufacturer Siemens claims that installation of the system on the "Ellsworth Corridor" cut travel time there by 12 percent on weekdays and 21 percent on weekends.

---

Got a question? Email question@aaobserver.com.     (end of article)

[Originally published in May, 2018.]

 



 
Bookmark and Share
Print Comment E-mail

You might also like:

The Ulta Secret
Its split-store model lets beauty aficionados mix and match.
Sabine Bickford
Nightspots: Zou Zou's Cafe
Subscribe to the Ann Arbor Observer
Doing Chinese at Christmas
Table Talk: December 2018
Linda R. Benson
Crime Map
A clickable, zoomable map
Photo: Running Away
Dalat Arrives
Joining the move to Ann Arbor
Sabine Bickford
Baked Goods Ice Cream And Chocolates in Chelsea
Family, Teens, & Kids Stuff
Leyla Conlan Gets Her Own Space.
The Write Touch gains a storefront, and a name
Sabine Bickford
Regent Hotel
Delux Drapery offers window treatments in Ann Arbor, Michigan like draperies, curtains, shutters & H
A visitor's guide to Ann Arbor