Patent ID: 7636169

Claim:
A sensing system comprising: at least one fluid bladder; at least one illumination device coupled to said fluid bladder and operable to generate and direct at least one illumination beam into said fluid bladder; a first light sensor coupled to said fluid bladder, comprising a first light filter, and operable to generate a first signal in response to at least a first received portion of said at least one illumination beam; and a second light sensor coupled to said fluid bladder, comprising a second light filter for filtering a frequency range different than that which is filtered by said first light filter, and operable to generate a second signal in response to at least a second received portion of said at least one illumination beam; wherein said first light sensor and said second light sensor positioned relative to said at least one illumination device for distance determination between said at least one illumination device and at least one of said first light sensor and said second light sensor.