I built a base for the clock last night and asked Kelly to try reading the time. We learned several things in the process:
- Tracing a circle is difficult when you can’t see. Kelly didn’t have a sense of the size of the outer ring with her eyes closed, so her fingers went off the ring several times. Each time, she had to return to the 12 o’clock index marker and start again.
- I built a prototype with a visual mapping that doesn’t correspond with the way we speak the time. Since Kelly and I have been using clocks for a long time (although she can read the non-digital ones much more quickly), we expect the longer hand to always point to the number of minutes. When I designed this clock, I thought the outer ring should also represent the minutes in order to mimic the way we’re used to seeing a clock. This would be a positive thing for a visually impaired person with memories of clock faces. For a person blind from birth, however, this visual/spatial mapping doesn’t exist. The way we speak the time, “four forty-nine, pm” rather than “eleven minutes to five o’clock, pm” defines a mental sequence: hours, then minutes. With this mental sequence, it makes sense that the outer ring is the hours and the inner ring the minutes. Despite our visual/spatial maps, Kelly and I both found our minds wanted to use the outer ring to represent hours when our eyes were closed.
- 12 != 1 != 0 (or twelve doesn’t equal one doesn’t equal zero). Another problem of the traditional clock face is tied to starting with twelve. Kelly experienced difficulty remapping the 12 o’clock position as zero when she couldn’t see the clock face. I realized that it doesn’t make sense if you haven’t grown up looking at a clock. My instructions to her were to “trace clockwise around the circle, counting each depression until you reach the raised marker.” I could either clarify my instructions or try another prototype which addresses some of these issues.
I began to experience firsthand some of the blocks we put in place as we consider designs. I stereotyped the user of my clock (in this case a visually impaired or completely blind person) as a sighted person in several key areas.