Pattern Signals at the Community Bike Shop

A message test in two shop areas

At the Wheelworks Community Bike Shop, volunteers needed to send short requests while helping visitors. One volunteer sent a pattern, and another volunteer used a key to identify the request. The team tested two ways to send information: a strip of colored tiles and a sequence of pedal clicks. Each pattern had three parts, and the receiver read each part from left to right.

The tile key used red and blue tiles. Red-blue-red meant “pump tire.” Red-blue-blue meant “adjust seat.” Blue-red-red meant “check chain.” Blue-red-blue meant “find helmet.” The click key used short and long clicks in the same pattern positions. Short-long-short meant “pump tire.” Short-long-long meant “adjust seat.” Long-short-short meant “check chain.” Long-short-long meant “find helmet.”

The team tested both systems in the quiet repair bay and in the busy front sidewalk area. For each system and place, volunteers sent the four requests three times each. The same four requests were used in every trial. The receiver stood six meters from the sender. In the sidewalk area, passing bicycles and conversations made the setting busier, but the team did not add those sounds to the repair bay.

The log recorded the results. In the quiet repair bay, tile strips had 11 correct messages out of 12 and took an average of 6 seconds per message. Clicks had 9 correct out of 12 and took an average of 4 seconds. In the busy sidewalk area, tile strips had 8 correct out of 12 and took an average of 7 seconds. Clicks had 6 correct out of 12 and took an average of 5 seconds.

The volunteers wanted a code that would carry the intended request clearly. They also considered how quickly a sender could send a pattern. A new pattern could be added only if it was different from the patterns already assigned to the four requests.