Early field experiments with auditory signage, as a supplement to tactile signage, were concerned with determining how well it worked and which design yielded the best performance. The American Council of the Blind sponsored a comparative evaluation of two technologies, Verbal Landmarks (VL) and Talking Signs® (TS), at their 1993 conventional hotel. VL is an inductive loop system that broadcasts an omni directional signal that gives instructions, whereas TS labels locations and gives a directional signal to that location. The use of convention participants as subjects resulted in a good cross-section of the blind population (Bentzen & Mitchell, 1995) . Bentzen designed an experiment to evaluate the two systems in a non-laboratory setting. Subjects were evaluated on three routes of different complexity. Significantly more users of VL, compared to TS, reached incorrect destinations, gave up on routes, or required assistance. Talking Signs® exhibited overwhelming performance advantages over Verbal Landmark in both travel time and travel distance. Subjects using Talking Signs® were significantly less likely to become frustrated and unable to independently complete the route than was the case with participants who used Verbal Landmarks.
Post-test surveys and rating questions were conducted to gather subjective data from the participants. Verbal Landmarks were rated as decreasing ease and speed of travel while Talking Signs® were considered to increase speed of travel and ease of use. In addition, Talking Signs® were rated significantly higher in user desirability for installation, ease of message comprehension, and ease of use.
An evaluation of Talking Signs® in a campus environment was conducted at San Francisco State University (Crandall et al., 1994) . Sixteen blind subjects navigated six routes twice. Significantly more routes were successfully completed using Talking Signs ® than with only verbal instructions. The efficacy of Talking Signs® was noted with 94% of the subjects agreeing that they would want to carry a receiver in both familiar and unfamiliar areas. Subjective responses on evaluation questions showed that the majority “strongly agreed” that the system was easy to use, that it was easy to learn to scan, and that the messages were easy to pick up and easy to understand. Furthermore, 62% “strongly agreed” that, once they got a signal, it was easy to follow it to the destination.
The campus experiment raised the question of how the level of training was related to the ease of use, learning to scan, ease of picking up messages, and following signs to destinations. Training requirements for effective and safe use of Talking Signs ® were evaluated at San Francisco’s Powell Station (Crandall, Bentzen, Myers et al., 1995 ; Crandall, Brabyn et al., 1999 ; Bentzen et al., 1999) . They wanted to determine the minimum amount of training required for a person to effectively and safely use Talking Signs®, whether by hands-on experience or by instruction. A group of 36 visually impaired people used the Talking Signs ® system as an aid to navigation through this complex subway station in downtown San Francisco. Subjects were divided into three groups, each group matched for familiarity with the station, use of transit modes, type of regular aid used, and degree of vision and mobility skills. Each group received a different amount of training on the proper use of the RIAS system.
Each group was tested for one hour on their ability to travel routes of increasing
complexity in the station. Subjects were not allowed to request information
or assistance. A full 97% of subjects were able to complete at least
two easy routes, and 67% succeeded in traveling some medium and hard routes
in the one-hour time allotted. The group that had no personal instructions
was not as successful as the other groups, but the amount of training did not
significantly affect route completion.
Locating bus stops and choosing from a group of buses have long been problems for blind transit users ( Crandall et al., 1996 ; Bentzen et al., 1999) . Crandall and associates conducted a test to determine the efficacy of Talking Signs® in these two situations. Eighteen blind subjects were tested regarding finding and correctly identifying three types of bus stops. Bus stops were fitted with tactile signs and TS. When trying to find a bus stop that was at a single pole, no subjects found it with their regular method. With TS, 15/18 subjects found the sign. The other two bus stops were shelters, one at the curb line and one at the building line. Significant improvements were also noted in finding the shelter by the curb. The results for finding the shelter at the building line were about equal. Mean times to find the correct bus stop were also quicker but highly variable and not significantly different for the two shelters. Dog users reported that finding bus stop poles with their dog was very hard, because the dog tried to steer them away from obstacles.
In their other experiment, three stationary buses were lined up in a row, and subjects were asked to find the correct bus. It appears that the design of this experiment resulted in no significant difference being found between subjects using TS and subjects’ regular methods. A researcher was always there to act as the bus driver to answer questions, there were no pedestrians or other obstacles in the way, and the buses were not approaching and leaving as in a normal situation. Therefore, subjects were able to walk directly along the curb to approach each bus and always got a correct and prompt answer when they asked the “bus driver.”
However, their answers to post-test questions revealed a very strong preference
for the TS system. Nine questions were asked about the ease of use, understanding
of messages, and their desire to use the system. Between 93% and 100%
either agreed or strongly agreed in a favorable way with these nine questions.
Subjective data from focus groups also were highly favorable towards the use
of TS to label bus stops and buses. Subjects often mentioned problems
in asking and receiving appropriate help and feeling safe while in this vulnerable
situation. Talking Signs® were seen as a way to be more
independent and to not have to rely on others for help.
Crossing streets and getting suitable information about an intersection are difficult, sometimes impossible, tasks for the blind. Bentzen et al. (1999) , Crandall, Bentzen, & Myers (1999) , and Crandall, Brabyn et al. (1999) evaluated 20 blind subjects making street crossings at four complex signalized crossings in downtown San Francisco. Without TS, subjects requested assistance in locating the crosswalk and requested assistance completing the crossing 19% of the time; participants requested assistance about knowing when the Walk interval began on 22.5% of crossings; and started their walk during the Don’t Walk or Wait signal 17%of the time.
Talking Signs® information included the timing of the Walk interval, the shape of the intersection, the angle of the crosswalk, the nature of the traffic control system, and spatial information about the street names, block number, and direction of travel. This additional information made crossings more successful and more independent. With Talking Signs, no participant requested assistance locating the crosswalk and also in completing the crossing on only one trial (3%), respectively; no participants asked when the Walk signal started; and just one crossing was started in an unsafe condition (when the Walk signal was not present).
Unsafe street crossings cause much anxiety for blind travelers, many of whom do not venture beyond familiar areas, thus restricting their range of travel and activities. The presence of a researcher at these “independent” crossings probably made subjects feel safer and led to fewer requests for assistance then would normally have been the case while traveling independently using their regular methods. Use of the Talking Signs ® system at intersections should vastly increase safety at these dangerous spots. The information about the timing of the Walk interval can give assurance to vision-impaired pedestrians, as it does to the sighted, that they have the right of way at a cross walk. It is also important to begin the crossing at the earliest appropriate moment in order to allow adequate time for completing the street crossing.
Taken together, these studies point to further research in the efficacy of
TS in larger and more complex situations as well as to gather much more subjective
data on the impact that this system had on people’s lives, their travel
behavior, and their activity choice.
Early field experiments with auditory signage, as a supplement to tactile signage, were concerned with determining how well it worked and which design yielded the best performance. The American Council of the Blind sponsored a comparative evaluation of two technologies, Verbal Landmarks (VL) and Talking Signs ® (TS), at their 1993 conventional hotel. VL is an inductive loop system that broadcasts an omni directional signal that gives instructions, whereas TS labels locations and gives a directional signal to that location. The use of convention participants as subjects resulted in a good cross-section of the blind population (Bentzen & Mitchell, 1995) . Bentzen designed an experiment to evaluate the two systems in a non-laboratory setting. Subjects were evaluated on three routes of different complexity. Significantly more users of VL, compared to TS, reached incorrect destinations, gave up on routes, or required assistance. Talking Signs® exhibited overwhelming performance advantages over Verbal Landmark in both travel time and travel distance. Subjects using Talking Signs® were significantly less likely to become frustrated and unable to independently complete the route than was the case with participants who used Verbal Landmarks.
Post-test surveys and rating questions were conducted to gather subjective data from the participants. Verbal Landmarks were rated as decreasing ease and speed of travel while Talking Signs® were considered to increase speed of travel and ease of use. In addition, Talking Signs® were rated significantly higher in user desirability for installation, ease of message comprehension, and ease of use.
An evaluation of Talking Signs® in a campus environment was conducted at San Francisco State University (Crandall et al., 1994) . Sixteen blind subjects navigated six routes twice. Significantly more routes were successfully completed using Talking Signs ® than with only verbal instructions. The efficacy of Talking Signs® was noted with 94% of the subjects agreeing that they would want to carry a receiver in both familiar and unfamiliar areas. Subjective responses on evaluation questions showed that the majority “strongly agreed” that the system was easy to use, that it was easy to learn to scan, and that the messages were easy to pick up and easy to understand. Furthermore, 62% “strongly agreed” that, once they got a signal, it was easy to follow it to the destination.
The campus experiment raised the question of how the level of training was related to the ease of use, learning to scan, ease of picking up messages, and following signs to destinations. Training requirements for effective and safe use of Talking Signs ® were evaluated at San Francisco’s Powell Station (Crandall, Bentzen, Myers et al., 1995 ; Crandall, Brabyn et al., 1999 ; Bentzen et al., 1999) . They wanted to determine the minimum amount of training required for a person to effectively and safely use Talking Signs®, whether by hands-on experience or by instruction. A group of 36 visually impaired people used the Talking Signs ® system as an aid to navigation through this complex subway station in downtown San Francisco. Subjects were divided into three groups, each group matched for familiarity with the station, use of transit modes, type of regular aid used, and degree of vision and mobility skills. Each group received a different amount of training on the proper use of the RIAS system.
Each group was tested for one hour on their ability to travel routes of increasing complexity in the station. Subjects were not allowed to request information or assistance. A full 97% of subjects were able to complete at least two easy routes, and 67% succeeded in traveling some medium and hard routes in the one-hour time allotted. The group that had no personal instructions was not as successful as the other groups, but the amount of training did not significantly affect route completion.
Locating bus stops and choosing from a group of buses have long been problems for blind transit users ( Crandall et al., 1996 ; Bentzen et al., 1999) . Crandall and associates conducted a test to determine the efficacy of Talking Signs® in these two situations. Eighteen blind subjects were tested regarding finding and correctly identifying three types of bus stops. Bus stops were fitted with tactile signs and TS. When trying to find a bus stop that was at a single pole, no subjects found it with their regular method. With TS, 15/18 subjects found the sign. The other two bus stops were shelters, one at the curb line and one at the building line. Significant improvements were also noted in finding the shelter by the curb. The results for finding the shelter at the building line were about equal. Mean times to find the correct bus stop were also quicker but highly variable and not significantly different for the two shelters. Dog users reported that finding bus stop poles with their dog was very hard, because the dog tried to steer them away from obstacles.
In their other experiment, three stationary buses were lined up in a row, and subjects were asked to find the correct bus. It appears that the design of this experiment resulted in no significant difference being found between subjects using TS and subjects’ regular methods. A researcher was always there to act as the bus driver to answer questions, there were no pedestrians or other obstacles in the way, and the buses were not approaching and leaving as in a normal situation. Therefore, subjects were able to walk directly along the curb to approach each bus and always got a correct and prompt answer when they asked the “bus driver.”
However, their answers to post-test questions revealed a very strong preference for the TS system. Nine questions were asked about the ease of use, understanding of messages, and their desire to use the system. Between 93% and 100% either agreed or strongly agreed in a favorable way with these nine questions. Subjective data from focus groups also were highly favorable towards the use of TS to label bus stops and buses. Subjects often mentioned problems in asking and receiving appropriate help and feeling safe while in this vulnerable situation. Talking Signs® were seen as a way to be more independent and to not have to rely on others for help.
Crossing streets and getting suitable information about an intersection are difficult, sometimes impossible, tasks for the blind. Bentzen et al. (1999) , Crandall, Bentzen, & Myers (1999) , and Crandall, Brabyn et al. (1999) evaluated 20 blind subjects making street crossings at four complex signalized crossings in downtown San Francisco. Without TS, subjects requested assistance in locating the crosswalk and requested assistance completing the crossing 19% of the time; participants requested assistance about knowing when the Walk interval began on 22.5% of crossings; and started their walk during the Don’t Walk or Wait signal 17%of the time.
Talking Signs® information included the timing of the Walk interval, the shape of the intersection, the angle of the crosswalk, the nature of the traffic control system, and spatial information about the street names, block number, and direction of travel. This additional information made crossings more successful and more independent. With Talking Signs, no participant requested assistance locating the crosswalk and also in completing the crossing on only one trial (3%), respectively; no participants asked when the Walk signal started; and just one crossing was started in an unsafe condition (when the Walk signal was not present).
Unsafe street crossings cause much anxiety for blind travelers, many of whom do not venture beyond familiar areas, thus restricting their range of travel and activities. The presence of a researcher at these “independent” crossings probably made subjects feel safer and led to fewer requests for assistance then would normally have been the case while traveling independently using their regular methods. Use of the Talking Signs ® system at intersections should vastly increase safety at these dangerous spots. The information about the timing of the Walk interval can give assurance to vision-impaired pedestrians, as it does to the sighted, that they have the right of way at a cross walk. It is also important to begin the crossing at the earliest appropriate moment in order to allow adequate time for completing the street crossing.
Taken together, these studies point to further research in the efficacy of TS in larger and more complex situations as well as to gather much more subjective data on the impact that this system had on people’s lives, their travel behavior, and their activity choice.
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