Wearable bands and electromyographic gesture detection for command and control of wearable computing devices
View Patent ↗An electromyographic gesture detection system for wearable devices, useful for entering text, selecting, controlling and manipulating virtual objects and smart applications on a display using gestures of the user. A wearable band is adapted to allow electromyographic detection and classification of specific gestures. The wearable device in some embodiments may also be adapted to recognize certain characteristics of the gestures, such as duration or amplitude, to allow enhanced navigation of a computer interface.
1 . A wearable electromyographic input system comprising:
a wearable assembly configured to be worn on a user;
a plurality of needle-less surface electrodes including at least one reference electrode and a plurality of signal electrodes, the wearable assembly configured to provide dry, non-adhesive touch-based contact between the electrodes and the user's skin when the wearable assembly is worn, the electrodes configured to measure myoelectric voltage differentials; and
a processor operatively coupled to the electrodes;
wherein the processor is configured to:
(i) determine, from the myoelectric voltage differentials, an amplitude value indicative of strength of muscle activation;
(ii) compute a control-effect magnitude by applying a nonlinear mapping function to the amplitude value; and
(iii) determine, based on the myoelectric voltage differentials, a direction of a control effect selecting between a first direction and an opposite second direction of a control axis, whereby a virtual object is manipulated in accordance with the control-effect magnitude and the selected direction.
2 . The system of claim 1 , wherein the control-effect magnitude controls a rate of change of a parameter of the virtual object rather than an absolute value of the parameter.
3 . The wearable electromyographic input system of claim 1 , wherein the control effect comprises applying a simulated physical force or torque to the virtual object.
4 . The wearable electromyographic input system of claim 1 , wherein the control effect is a vector quantity comprising the control-effect magnitude and the selected direction.
5 . The system of claim 1 , wherein the nonlinear mapping function comprises an exponential function of the amplitude value.