The project team has been experimenting with combinations of number of motors, vibration intensity, pulse timing, and so on.
One interesting result is that when motors are given a sudden start and random decay (across all 6 motors), the effect feels like raindrops.
Despite this, sensory measurement seems difficult to achieve: each motor vibrates a section of the tape (holding the motors), in such a way that it's difficult to distinguish one motor from another.
My next task is to see if there's a way to mechanically isolate the motors, so that their buzzing doesn't vibrate more than the motor itself.
Seven, Plus or Minus Two
In the highly cited paper "The Magical Number Seven, Plus or Minus Two", it is revealed that the channel capacity for distinguishing stimuli is roughly 7 in any dimension.
From that paper, I found the following:
The whole paper is an easy read and highly interesting, well worth the time.