Patent ID: 8766910

Claim:
A method comprising: receiving a plurality of signals from a sensor array disposed on a side wall of a non-movable, non-mechanical protrusion, wherein the protrusion is integrated into a surface of a control panel of a device as one integrated piece and physically resembles a mechanical knob that protrudes from the surface of the control panel of the device, wherein the protrusion extends out from the surface of the control panel such that a user's hand can at least grab an outer surface of the protrusion or move over the outer surface to operate the device and includes an opening on a back side of the protrusion that allows access to the side wall of the protrusion; and detecting interaction of the user's hand with the sensor array based on the plurality of signals when the user's hand grabs the protrusion or moves over the outer surface; wherein detecting the interaction comprises: detecting presences of multiple conductive objects on the sensor array; determining positions of the multiple conductive objects; and identifying one of the multiple conductive objects as a finger and isolating the finger as a reference indicator based on the positions of the multiple conductive objects, wherein identifying one of the multiple conductive objects as the reference indicator comprises: determining a distance between each directly adjacent position of the multiple conductive objects based on a capacitance maximum for each of the multiple conductive objects, wherein each capacitance maximum corresponds to the positions of the multiple conductive objects; and identifying a reference position using two greatest distances between the directly adjacent positions of the multiple conductive objects, wherein the one of the multiple conductive objects that is located at the reference position is identified as the finger.