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PhET John Travoltage Archived Content

PhET John Travoltage Archived Content

Dec 10, 2015

Old Design Notes

360 rotation of the arm

  • could be confusing to a non-visual user since there is no beginning or end

  • perhaps we can limit the rotation (i.e. 270 degrees)

Audio feedback for location of arm

  • approach 1: have the door-knob act as a landmark and have the rotation described or sonified as a distance from the door knob.

    • Example hand approaching and going away from:

      • "Hand is moving closer to the door knob." / "Hand is moving away from the door knob."

      • If sonified using pings, the pattern may look be like this: ".    .   .  .  . . . ..... . .  .  .   .   .   .     ."  

    • disadvantage: this implies some importance to the door knob. May preclude any other discoveries like the effect of distance.

    • Response:

      • it's okay to describe the proximity of the door knob.

  • approach 2: use some sort of scale (degrees, or clock face) to indicate arm rotation.

    • disadvantage: this is cognitively harder to understand and introduces a scale which the learner may not be familiar with.

  • Arrow keys with accelerator, spatial description relative to the door knob.

Keyboard Tab Order - Leg or Arm first?

Arm is first

  • The user may spend time moving the arm without an effect. This may actually be desirable as it could reinforce the learning outcome.

  • However, if the arm is first, a user of a screen reader may take longer to figure out what is (not) happening because of the serial nature of the feedback.

  • During an informal observation of a sighted user, they spent a while moving the arm around wondering if they did something wrong. They were almost going to give up until they tried the leg. For a non-sighted user, this process of discovery will take much longer.

Leg first

  • The user experiences a more immediate result if starting with the leg first.

  • The current default arm position will cause a discharge of electrons if enough electrons are gathered. Is this intentional?

  • Response:

    • PhET design - your start begins with something that does something. Therefore start with the leg.

Leg movement

  • explore use of accelerator key (CTRL + Left / Right).

  • describe leg position relative to contact with the carpet.

Visual and Audio Prompts

  • Does using arrows and text descriptions to indicate directions of movement give away too much of the interaction? Is this acceptable?