Case Study — Ann Arbor, Michigan

Date: April 2005

History and Background

Ann Arbor has been using pushbutton-integrated APS since 2001. Five were installed that year and none have been added since.

Process and Procedure

APS are installed on the basis of recommendations from the Ann Arbor Commission on Disability Issues.


Approval for APS funding comes through the City Council. The money is budgeted from the Major Street Fund, which is a transportation fund. Currently, $50,000 is designated for the purchase, installation and maintenance of five APS.

APS Type and Features

Pushbutton-integrated devices (Navigator) from Polara Engineering

APS features:

Installation Issues

All APS installations were retrofits to existing signals on steel poles, and existing wiring was sufficient to accommodate APS installation. Some units are installed on pedestrian signal poles and some are mounted on the vertical pole of a signal mast arm.


Many of the APS units began to malfunction in 2004 and the city sent them back to the manufacturer for repair/replacement. The problem was observed to be rusting of the devices.

Vandalism was an issue. There were several instances where the unit was knocked off the pole. The attachment bolts were replaced with bigger diameter bolts.

Cold Weather Issues

Little direct effect was seen from cold weather conditions. However, the use of salt may have contributed to rust that was experienced. The city engineers do not believe that the winter conditions contributed much to the problems.


There were several complaints about the noise of the locator tones, especially in the summer when people keep windows open. The locator tone volume was lowered in response and where there were two APS units on a single pole, one of the the locator tones was switched off to control noise. To explain how the APS devices work, the city publicized the devices through a newspaper article and local cable broadcast.


Les Sipowski
Senior Project Manager, City of Ann Arbor Public Services Department
Ann Arbor, Michigan
Phone: (734) 996-3286

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