scenario set 2. Build your own LED detector

[venkateshpotluri]

Why are these scenarios important? what is different?

Many appliances such as wi-fi routers, electrical power surge protectors, and instant pots convey their activation status and the current function they are performing through LEDs. This set of scenarios explores ways to provide light sensor information that BVI developers may need to program their own LED status indicators for specific devices and scenarios. Currently, light detectors have offered limited capabilities in such contexts as programming -- they only indicate relative levels of brightness using sound or audio cues. These set of scenarios demonstrate the potential of getting access to raw and relative values from light sensors.

Scenario 2.1. determine the threshold to be able to detect if a particular LED is on or off, or if the sensor is not placed on a LED for detection.

goal: user wants to know about the current status of an instant pot. The pot indicates status through non-tactile LEDs next to each function button. As the LEDs are non-tactile, the user could potentially place the detector where there is no LED and wants to be alerted in that case as well.

1. user connects a Jacdac-based pen-shaped light detector to the sensor data sonifier (web interface).
2. User attaches a temporary "record value" jacdac button.
3. User starts to sonify the data.
4. With assistance from a sighted person or independently, user enables different functions on the pot and places the light sensor on the corresponding LEDs.
5. User hears the sensor value change.
6. User notes the values by pressing the record value button. The values are recorded with an incrementing sequence of marks.
7. User repeats steps 4,5 and 6 to make sure they are trying to account for the potential for erroneous values due to the high sensitivity of the light sensor to determine a good threshold.
8. User saves the data for each LED separatly.
9. user repeats steps 4-7 by placing the light detector in locations where there are no LEDs and records these values as well.
10. User studies the noted values in the data and notes them.
11. User loads the data and authors an auditory display to highlight these values of interest when they occor in the data.
    1. User selects the [highlight points] option in the interface.
    2. User enters a comma separated set of values to highlight them.
    3. User presses play and hears the audio.
    4. user uses the same values of interest from one of the scenario in the other 2 scenarios to detect overlaps.
12. user develops the threshold and necessary auditory feedback to be able to use their own light detector personalized to their pot and lighting conditions in their home.

Scenario 2.2. Identify thresholds to detect the color of a LED.

Many public spaces provide critical information through colors of LEDs. For example, bathrooms provide occupancy status through LEDs next to the door. This scenario assumes that a BVI developer wants to build an occupancy status indicator without having to awkwardly push the door and become aware of the occupancy status.

1. User identifies the different possible colors of the LED by talking to a sighted colleague. For the sake of this scenario, let us assume that red indicates occupied and green indicates ready to use.
2. BVI user identifies the location of the LEDs.
3. BVI user searches for possible light sensor value ranges for the 2 colors.
4. BVI developer authors an auditory display indicating the range as region of interest for one of the 2 colors.
   1. user enters the range of possible values for one of the 2 colors.
   2. User indicates a small window (e.g. plus or minus 5 percent).
   3. Using a popup box, User indicates that they want to hear a small beep if the value from the window occurs.
   4. Using a checkbox, user indicates that they want to hear white noise for values not in the region of interest.
5. User presses the play button, moves the sensor to the LED, and listens to the audio.
6. User repeats steps 4 and 5 for the second color.
7. When authoring an auditory display in step 5, The user adds a second region of interest and uses the range from the first color. The user indicates to play a different sound from a list of pre-set sounds when the value from the second region appears. This helps detect overlaps.
8. user gets the thresholds and builds the occupancy detector.