FAQ

How can I help?

Great! We really appreciate your help! It would be very helpful if you could use our tool to audit accessibility of neighborhoods. By accessibility audit, we mean:

  1. Click Start Auditing.
  2. Take an interactive tutorial to learn how to use our tool (if you haven't taken one before).
  3. Walk along the streets and explore the neighborhood to find and label accessibility features.

Please watch the following video to see the demo of how the accessibility audit works:

Can I select a neighborhood to audit?

Yes! Please follow the following steps:

  1. Sign in with your account (if you don't have an account, please sign up!)
  2. Go to your dashboard
  3. Select the neighborhood that you want to audit on the map

Is Google Street View a reliable data source?

Google Street View provides a rich visual data source to inspect a city without leaving your home. However, the images shown are collected periodically every few years. Hence, they might be out of date. Indeed, some users have reported that problems shown in our interface have recently been resolved. Generally, however, street-level infrastructure does not change very often. We have conducted two studies of our own that compare audit data from our online interfaces to audit data collected via traditional, in-person walk-around audits [1,2]. In both cases, we found high agreement--in other words, the images in Google Street View are a good representation of the state of the physical world. This is consistent with findings from previous studies [3, 4, 5].

Moreover, with the advancement of GSV technology, imagery is likely to become even more accurate than it is already.


References

What to do when navigation arrow disappears?

Sometimes during auditing, you would have noticed that the navigation arrows go missing, especially, while walking straight. Worry not, there is a simple solution!

Just double click on the street to move ahead and you are all set!

What should I do when I find conflicting Street View images?

An older Street View image without a curb ramp at the end of crosswalk
An older Street View image without a curb ramp at the end of crosswalk. You should label the problem as a "Missing Curb Ramp."
A newer Street View image of the same location. The problem is fixed.
A newer Street View image of the same location. The problem is fixed and there is a curb ramp, so you should label this as a "Curb Ramp."

From time to time, you'd observe Street View images taken at the same location at different time, and the environment in the images may be conflicting--just like the pair of the Street View images shown above. In the older image on the left, there is no curb ramp at the end of the crosswalk, but the problem is fixed in the newer image on the right. If you find a similar case, please label the accessibility features in both images so we can keep track of how the environment has changed over time!

Why do my labels disappear?

Yes, you're right, labels do disappear after you take a step in the Google Street View interface but don't worry, we store all of your labels.

So, why does it work like this? Well, the answer is kind of complicated but the short answer is: the Google Street View interface is akin to a 3-dimensional interface similar to walking in the real world. When you place a label, we convert the 3D position of the label to a 2D lat/long position. However, once you take a step to a new location, we cannot accurately recompute the label's position in 3D for that new view. See, we told you it was kind of complicated. :) Rest assured, you can always see your applied labels in the top-down map in the bottom-right hand corner of your screen.

Are there keyboard shortcuts for the image labeling interface?

Yes. Here is the list of keyboard shortcuts:

Key What it does
Mode Switch E Switch to the Exploration mode
C Switch to the Curb Ramp mode
M Switch to the Missing Curb Ramp mode
O Switch to the Obstacle in Path mode
S Switch to the Surface Problem mode
B Switch to the "Can't see the sidewalk" mode
N Switch to the "No Sidewalk" mode
Label Rating 1 2 3 4 5 Set corresponding rating
Enter Close label rating
Interface Control Z Zoom in
Shift + Z Zoom out
Up Move Forward
Down Move Back
Left Rotate point of view left
Right Rotate point of view right

The Street View images are not showing up, what should I do?

Sometimes the Street View window images could not be correctly loaded and you see nothing but a grey window even if you move around. This could happen for various reasons, e.g., you could be in a location where Google Street View images are not available. To fix this, you can reload your page. Note that all of your previous labels will be saved and you can continue your current mission after reloading.

Are there any severity rating examples?

Yes, here are some examples:

Curb Ramp

Two good curb ramps

Rating 1: Passable

Clean curb ramps that are aligned with crosswalks.

Water has accumulated in the curb ramp

Rating 3: Neutral

A curb ramp with a pole standing in the middle. People who use large electrical wheelchairs may have trouble using this curb ramp.

Water has accumulated in the curb ramp

Rating 5: Not passable

Water has accumulated in this curb ramp due to poor drainage. It is hard for manual wheelchair users to use this curb ramp.

No Curb Ramp

Curb ramp is not aligned to the crosswalk

Rating 1: Passable

Although there is no curb ramp, the level difference is small and wheelchair users would be able to get on or off the sidewalk. There is also a curb ramp at the same corner that people could use, although it is not aligned to the path.

No curb ramp at the end of the crosswalk

Rating 3: Neutral

There is no curb ramp at the end of the crosswalk. Wheelchair users are forced to used the curb ramp that is not aligned with the crosswalk.

No curb ramp at the end of the crosswalk

Rating 5: Not passable

No curb ramp at the end of the crosswalk. Wheelchair users cannot get on or off the sidewalk and cross the street here.

Obstacle

Overgrown bush is partly blocking the path.

Rating 1: Passable

A traffic light standing in the middle of the sidewalk. There seems to be enough space for wheelchair users to pass, but those who are using larger chairs could have trouble navigating.

Overgrown bush is partly blocking the path.

Rating 3: Neutral

The plant is obstructing the path, making it hard for wheelchair users to use this sidewalk.

A tree is completely blocking the path.

Rating 5: Not passable

The tree is completely blocking the path, making it not passable for wheelchair users.

Surface Problem

A partially damaged sidewalk.

Rating 1: Passable

Partially damaged sidewalk. Because there is enough space next to the damaged part of the sidewalk, wheelchair users would be able to pass.

Cobblestone sidewalks and crosswalks.

Rating 3: Neutral

Wheelchair users would have difficulty navigating on the cobblestone sidewalks and crosswalks.

A tree is completely blocking the path.

Rating 5: Not passable

Wheelchair users cannot pass severely degraded sidewalk surfaces due to the over-grown vegetation.

Contact Us

You have more questions? Email us (sidewalk@umiacs.umd.edu), post a GitHub issue, or follow and talk to us on Twitter (@umd_sidewalk)!