Hello Everyone,
I will be presenting our paper that examines the effect of Smartphone Alerts and Warnings on Street-Crossing Behavior in Non-Mobility-Impaired Older and Younger Adults.
Governmental agencies and vehicle manufacturers are exploring sophisticated vehicle technology all over the world.
One such technology is Vehicle-to-everything or Vehicle-to-X,
which is technology that enables a vehicle to communicate with anything that might affect its movement.
This can include communication with other vehicles.
In fact, Vehicle-to-Vehicle communication technology is in the process of design and implementation in New York City.
This can also include communication with networks such as servers that give information about certain routes,
Or infrastructure such as traffic signals,
Or it can include communication with pedestrians, for example to assist them in crossing decisions or display car intentions.
As technology like this advances and vehicles get smarter, there will be inevitable changes to our road networks.
This is why it is important to understand how vulnerable road users like pedestrians
respond to different types of information presented to them.
Our work explores how vehicle-to-pedestrian communication may impact pedestrian street-crossing behavior.
In order to do this, we used a Virtual CAVE Environment to test ability-based phone alerts and warnings.
Our CAVE setup consists of 4 walls with projectors directed to each.
We used a smartphone to present ability-based permissive alerts with auditory, haptic, and visual feedback.
The following video shows a person receiving a permissive alert and they cross the virtual street.
[Smartphone] Safe to Cross
We also used a smartphone to display ability-based prohibitive warnings with auditory, haptic, and visual feedback.
The following video shows a person receiving a prohibitive warning and they don’t cross the virtual street.
[Smartphone] Do Not Cross [Smartphone] Do Not Cross
We define a “gap” as the time between two cars when a participant may have chosen to cross.
Permissive alerts were given when the approaching gap was safe to cross for the participant.
Prohibitive warnings were given when the approaching gap was not safe to cross for the participant.
We conducted a between-subjects study with 72 younger college-age participants
and 71 older participants with ages between 65 and 85.
We had three conditions: control - where no alerts or warnings were given,
prohibitive - where only prohibitive warnings were given,
and permissive - where only permissive alerts were given.
Some measures that we were particularly interested in were
which gap choices participants made in each condition,
and whether participants complied with the alerts or warnings.
We also gathered some qualitative data on their experiences with the alerts or warnings.
We found that participants took smaller gaps in the permissive condition than in our control condition.
Further, our qualitative findings uncovered that participants may have crossed when given permissive alerts, when they otherwise would not have.
And so, we conducted a follow-up condition where we only provided participants with permissive alerts on very large gaps
to see if we could shift street-crossing behavior towards greater caution.
We used the same methods and protocols as before for this condition.
We found that participants did end up selecting larger gaps in this condition than in our original, ability-based, permissive condition.
We also found that compliance with the alerts decreased with cautious permissive alerts,
with both younger and older participants crossing when they were not alerted to do so.
Our qualitative findings showed that cautious permissive alerts may be perceived as “too safe.”
With one participant saying that “a couple of times I felt like I could have crossed.”
Our qualitative findings also showed that participants found prohibitive warnings annoying.
One participant said, “After a while you’re just like, ok, I am tired of hearing that.”
So, in conclusion,
Participants took smaller gaps when given ability-based permissive alerts than in the control condition.
Participants took larger gaps in the cautious permissive condition than in the ability-based permissive condition.
Participants complied less with the cautious permissive alerts.
And participants found the prohibitive warnings annoying.
Thank you!