Physigrams

symbol meaning examples
state – physical state of the device
transient tension state – physical state which can only be maintained by some sort of continuous user pressure or exertion

transition
– this may be labelled by the user action that causes the transition, or this may be implicit. It may also have a label to connect it with a logical state (see linkage)
  self transition – special case of the above where a user action has no effect on the system (e.g. attempting to twist a dial beyond its limits)

bounce-back
– when the device spontaneously returns from a transient tension state to a stable state when user pressure is removed.
give – where a button or other control moves slightly but with resistance before ‘giving’ and causing state change. If the user stops exerting pressure before the ‘give’ point, it will return to the initial state.
slide transition – designer extension to denote situation when there are device changes that are not perceptible to the user
unfelt bounce-back – this is basically a press and bounce-back, but where there is no perceptual feedback

system-initiated transition
– where some internal computation, or environmental event not connected with the interacting user, causes a transition in the physical device
 

 


Logical State

symbol meaning examples

state
– state of the logical system

group
– where several lower-level states can be thought of as sub-states of a more abstract state. In the example, ‘POWER ON’ is a higher-level state, but within this state water may be below or at boiling point.

user–initiated state transition
– logical state transition initiated by external user activity (see also linkage)

system-initiated transition
– where some internal computation, or environmental event not connected with the interacting user, causes a transition in the logical system
 

TBD

 

 

Linkage

symbol meaning examples
state–state mapping – where the physically visible or tangible states in an exposed state device correspond precisely to states in the underlying logical system
user-initiated transition – where a state transition in the physical device caused by a user action gives rise to a transition in the logical state. The connection is denoted by the label, ‘(a)’ in the example.
system–initiated transition – where a spontaneous change or event in the system (denoted by the lightning symbol) triggers a physical state change in the device.