National Institute on Disability and Rehabilitation Research

Remote Infrared Signage Developmen to Address Current and Emerging Access Problems for Blind Individuals

A focus group of nine persons who participated in the human performance evaluation was held to obtain additional subjective data regarding the use of the Talking Signs system at intersections. The group met for approximately one and one half hours. (See Appendix)

First the group directed their attention to a number of questions related to the use of Auxiliary Messages on a second channel to provide additional descriptive information about each intersection. These Auxiliary Messages, if implemented in the Talking Signs application at intersections, would be accessed by most Talking Signs system users only when they were crossing unfamiliar intersections. The intersections crossed by participants in the human performance experiment were all unfamiliar to them, and they were asked to listen to the Auxiliary Message at each intersection before preparing to cross.

The group examined two hypothetical complex intersections, and particular crossings at those intersections, as they generated a comprehensive list of all information they might like to have included in a descriptive message, if the information applied to the intersection. The hypothetical complex intersections were used because all four intersections used in the experiment were relatively simple.

The group listed 16 kinds of information they would like to be able to receive on the Auxiliary Message where it was relevant for a given intersection. The 16 items were then rated in importance for inclusion, by having each focus group participant raise 1-5 fingers for each item (5 fingers = very important; 1 finger = very unimportant). (See Table 3.)

Type of Information to be Included in Auxiliary Messages	Mean Rating
Shape of intersection	4.7
Location of push button	4.2
Angle of the cross walk	4
Direction of traffic flow if one-way	4
Relationship of cross walk to any traffic islands	4
Number of lanes to be crossed	3.9
Presence of constant right turning traffic	3.9
Location of median	3.3
Vehicular actuation or other variations in signal timing	3.3
Length of walk interval (in seconds)	3.2
Location of curb ramp in relation to the crosswalk	3.1
Presence of a median	3
Street names	2.9
Landmarks	2.8
Relative length of the walk interval	2.8
Shape of islands	2.8

Table 3. Types of information desired for inclusion in descriptive messages, in order from very important to very unimportant (5 = very important). Data are mean rating values for nine participants who were blind.

There were three types of information provided by the Talking Signs system as participants experienced it during the experiment, orientation information, and walk/wait information, which were available on the primary channel, and descriptive information which was available on a second channel. Participants were asked to rate how important it is to provide each type of information at intersections using a show of 1-5 fingers, (5 fingers = very important, 1 = very unimportant).
Participants considered the Orientation information (Example: "Traveling East on the 800 block, toward Larkin Street.") the most important (mean = 4.7), followed by the "Wait .... "Walk Sign .... "(mean = 4.3). The descriptive information (Example: "This is a plus shaped intersection. It is controlled by a fixed timed traffic light in which the walk phase begins with the onset of traffic on Polk. Polk is one way coming towards you. The crosswalk is angled away from Polk. Grove is 6 lanes wide.") was considered essentially equal in importance ( mean = 4.2).

Next, participants were asked to consider advantages of the Talking Signs system and advantages of audible traffic signals such as the cuckoo and chirp signals they had experienced elsewhere.

Advantages of the Talking Signs System at Intersections

• The signal is highly directional and unambiguous
• The information is refusable
• The information is not heard by the general public
• The same information is provided as is available to pedestrians who are fully sighted
• The information is very specific
• There can be a lot of information

Advantages of Audible Traffic Signals at Intersections

• No receiver is needed
• There is nothing to carry in the hand
• The signals can be heard far away
• The user continues to hear the signal while crossing (as long as the Walk interval continues)
• All pedestrians are alerted to the onset of the Walk interval