Biometric-sensor assembly, such as for acoustic reflectometry of the vocal tract
A biometric-sensor assembly, e.g., for acoustic reflectometry of the vocal tract. In one embodiment, the sensor assembly includes a dental appliance for in-mouth mounting, an acoustic sensor attached to the dental appliance, and an optional headset. The dental appliance enables secure placement of the acoustic sensor in the mouth of the user, e.g., for tracking movements of the tongue and/or other internal articulators of the vocal tract. A boom arm of the headset can be used for holding an additional acoustic sensor and/or a miniature video camera, e.g., for tracking movements of the lips.
1. An apparatus, comprising:
a first acoustic speaker;
a first set of one or more first acoustic microphones; and
a dental appliance, wherein:
the first acoustic speaker and the first set of one or more first acoustic microphones are attached to the dental appliance so that, when the dental appliance is placed into a user's mouth:
the first acoustic speaker has a position that causes acoustic waves generated by the first acoustic speaker to enter the user's vocal tract; and
the first set of one or more first acoustic microphones has a position that causes acoustic waves reflected from the vocal tract to impinge onto at least one of the first acoustic microphones;
a second acoustic speaker configured to generate second acoustic waves;
a second acoustic microphone; and
a headset having an earpiece and a boom arm that is movable with respect to the earpiece, wherein both the second acoustic speaker and the second acoustic microphone are mounted on the boom arm, wherein:
when the headset is placed onto the user's head, the boom arm is configurable for:
the second acoustic speaker to have a position that causes the second acoustic waves to reflect off the user's lips; and
the second acoustic microphone to have a position that causes reflected second acoustic waves to impinge onto the second acoustic microphone.
2. The apparatus of claim 1 , wherein the dental appliance comprises a mouthpiece having a first groove and a second groove located on opposite sides of the mouthpiece and configured to accommodate an upper arch of teeth and a lower arch of teeth, respectively, when inserted into the mouth.
3. The apparatus of claim 2 , wherein the first and second grooves are configured to lock the user's mandible and maxilla with respect to one another.
4. The apparatus of claim 2 , wherein:
the first acoustic speaker is imbedded into a lingual wall of the mouthpiece; and
the first set of one or more first acoustic microphones is imbedded into the lingual wall.
5. The apparatus of claim 2 , further comprising a set of electrical wires configured to provide electrical connections to the first acoustic speaker and/or the first set of one or more first acoustic microphones, wherein the electrical wires protrude out from a labial wall of the mouthpiece.
6. The apparatus of claim 2 , wherein:
the mouthpiece has a U shape characterized by an approximate-symmetry plane;
at least one microphone of the first set is located to one side of the approximate-symmetry plane; and
at least one other microphone of the first set is located to another side of the approximate-symmetry plane.
7. The apparatus of claim 1 , wherein:
the dental appliance comprises a dental brace shaped to form-fit a specified arch of teeth;
the first acoustic speaker is attached to the dental brace; and
the first set of one or more first acoustic microphones is attached to the dental brace.
8. The apparatus of claim 7 , wherein the specified arch is a lower arch.
9. The apparatus of claim 7 , wherein the first acoustic speaker is attached to the dental brace so that, when the dental brace is placed in the mouth, the first acoustic speaker is located inside the mouth.
10. The apparatus of claim 7 , wherein the first set of one or more first acoustic microphones is attached to the dental brace so that, when the dental brace is placed in the mouth, the first set of one or more first acoustic microphones is located inside the mouth.
11. The apparatus of claim 7 , wherein the first acoustic speaker is attached to the dental brace so that, when the dental brace is placed in the mouth, the first acoustic speaker is located between the user's lips.
12. The apparatus of claim 1 , further comprising a video camera mounted on the boom arm.
13. The apparatus of claim 1 , further comprising a power source configured to provide electrical power to the first acoustic speaker and/or the first set of one or more first acoustic microphones, wherein the power source is incorporated into or attached to the dental appliance.
14. The apparatus of claim 1 , further comprising a wireless transceiver configured to:
receive control signals for the first acoustic speaker from an external transmitter; and/or
transmit signals generated by the first set of one or more first acoustic microphones to an external receiver, wherein the wireless transmitter is incorporated into or attached to the dental appliance.
15. An apparatus, comprising:
a first acoustic speaker;
a first set of one or more first acoustic microphones;
a second acoustic speaker;
a second acoustic microphone; and
a dental appliance, wherein:
the first acoustic speaker, the first set of one or more first acoustic microphones, the second acoustic speaker, and the second acoustic microphone are attached to the dental appliance so that, when the dental appliance is placed into a user's mouth:
the first acoustic speaker has a position inside the user's mouth that causes acoustic waves generated by the first acoustic speaker to enter the user's vocal tract;
the first set of one or more first acoustic microphones has a position inside the user's mouth that causes acoustic waves reflected from the vocal tract to impinge onto at least one of the first microphones;
the second acoustic speaker is configured to generate second acoustic waves and has a position outside the user's mouth that causes the second acoustic waves to reflect off the user's lips; and
the second acoustic microphone has a position outside the user's mouth that causes reflected second acoustic waves to impinge onto the second acoustic microphone.
16. The apparatus of claim 15 , wherein:
the dental appliance comprises a dental brace shaped to form-fit a specified arch of teeth;
the first acoustic speaker is attached directly to the dental brace; and
the first set of one or more acoustic microphones is attached directly to the dental brace; and
the second acoustic speaker and the second acoustic microphone are attached to a distal end of a holder, wherein a proximal end of the holder is attached to the dental brace so that a part of the holder is configured to fit between the user's lips.