Wearable electronic device for inducing transient sensory events as user feedback
A wearable electronic device includes an electrode array for transdermal stimulation of a sensory nerve that itself innervates a body part distal to a worn location of the wearable electronic device. The transdermal stimulation is configured to induce an electrical current or voltage that evokes a sensory impression at an area innervated by the sensory nerve, not at the stimulated sensory nerve itself. In one implementation, the wearable electronic device takes a finger ring form factor worn on a proximal phalanx of an index finger. In this configuration, the wearable electronic device can stimulate a portion of a branch of the median nerve extending through the index finger. Upon stimulation of the median nerve, a user wearing the finger ring may perceive pressure applied to the user's fingertip.
1. A wearable electronic device for stimulating referred sensation, the wearable electronic device comprising:
a housing defining an exterior surface configured to contour to a skin surface of a user;
an electrode array extending at least partially through the exterior surface to contact the skin surface;
a memory resource storing at least one executable asset; and
a processing resource operably coupled to the memory resource and configured to cooperate with the memory resource to access the at least one executable asset to instantiate an instance of software configured to:
determine a sense impression site at which to induce a sensation, the sense impression site distal to a stimulation site above a sensory nerve of the user, the sensory nerve innervating the sense impression site;
determine a sense impression modality corresponding to a sensation type to induce for the user at the sense impression site;
query a first data store with the sense impression site and sense impression modality to retrieve a stimulation profile comprising a magnitude and a polarity of current such that inducing the current in the sensory nerve causes an afferent signal that evokes a sensory impression localized at the sense impression site, the sensory impression corresponding to the sense impression modality;
query a second data store with the stimulation profile to retrieve a calibration profile comprising information relating locations of the electrodes of the electrode array to the user as the wearable electronic device is worn by the user;
query a third data store to obtain a user-specific profile comprising a threshold defining a limit to the magnitude of current of the stimulation profile;
create a stimulation plan with the stimulation profile, the user-specific profile, and the calibration profile, the stimulation plan comprising parameters defining at least one signal to apply across a selected pair of electrodes of the electrode array to induce, at the sensory nerve, the current having the magnitude and polarity as defined by the stimulation profile so as to induce the afferent signal; and
execute the stimulation plan by generating and applying the at least one signal across the selected pair of electrodes.
2. The wearable electronic device of claim 1 , wherein the housing has an annular shape and the wearable electronic device is configured to be worn on a finger of the user.
3. The wearable electronic device of claim 2 , wherein the finger is an index finger or a middle finger and the sensory nerve is a median nerve.
4. The wearable electronic device of claim 2 , wherein the sense impression site is a user's fingertip.
5. The wearable electronic device of claim 1 , wherein the wearable electronic device is configured to be worn on a wrist of the user.
6. The wearable electronic device of claim 1 , wherein a first electrode of the electrode array is formed from a first metal and a second electrode of the electrode array is formed from a second metal.
7. The wearable electronic device of claim 1 , wherein the user-specific profile comprises a maximum current that may be induced.
8. The wearable electronic device of claim 1 , wherein the instance of software is configured to receive a signal from a separate electronic device, the signal comprising an instruction to evoke a sensory impression for the user the sensory impression comprising the sense impression modality and the sense impression site.
9. The wearable electronic device of claim 8 , wherein the separate electronic device comprises a virtual computing environment.
10. The wearable electronic device of claim 1 , wherein the sense impression modality is selected from:
a pressure sense impression;
a temperature sense impression;
a texture sense impression; or
a time-varying mechanical sense impression.