Patent ID: 8588977

Claim:
An apparatus, comprising: a manipulator operable by a user; a force sensor that determines a force signal from a force applied by the manipulator on a part of an environment of the user; a signal modulator; a visual indicator; wherein the signal modulator is adjustable by the user to select a switch point for the visual indicator based on relative fragility of the part of the environment; wherein the signal modulator employs the force signal and the switch point to control the visual indicator for the user; wherein light intensity of the visual indicator is related to a magnitude of the force applied by the manipulator; and wherein the visual indicator comprises at least one LED including a first LED and a second LED, wherein the signal modulator employs the force signal at a first level below the switch point to turn on the first LED, wherein the signal modulator employs the force signal at a second level above the switch point to turn on the second LED.