Method of checking earphone wearing state

{
  "publication_number": "US9351090B2",
  "country": "US",
  "kind": "B2",
  "title": "Method of checking earphone wearing state",
  "abstract": "An information processing apparatus that detects an output from a 3-axis acceleration sensor included in an earphone unit worn by a user while the user is in a still state; monitors the output of the 3-axis acceleration sensor while a nodding gesture is performed by the user; detects a time when an angle of the nodding gesture reaches a maximum; and determines an earphone wearing state based on the output from the 3-axis acceleration sensor in the still state and the output from the 3-axis acceleration sensor at the time of detecting the maximum nodding angle.",
  "claims": [
    "1. An information processing apparatus comprising: circuitry configured to detect an output from a 3-axis acceleration sensor included in an earphone unit worn by a user while the user is in a still state; monitor the output of the 3-axis acceleration sensor while a nodding gesture is performed by the user; detect a time when an angle of the nodding gesture reaches a maximum by detecting an extremum in the output for a specific axis of the 3-axis acceleration sensor that varies during the nodding gesture; and determine an earphone wearing state based on the output from the 3-axis acceleration sensor in the still state and the output from the 3-axis acceleration sensor at the time of detecting the maximum nodding angle.",
    "2. The information processing apparatus of claim 1, wherein the circuitry is configured to: detect the time when the angle of the nodding gesture reaches the maximum by detecting a zero-crossing of a gyroscope included in the earphone unit that varies during the nodding gesture.",
    "3. The information processing apparatus of claim 1, wherein the circuitry is configured to: determine whether the earphone unit is being worn on the user's left ear or right ear based on whether an output corresponding to a specific axis of the 3-axis acceleration sensor that varies during the nodding gesture exhibits convex variation or concave variation.",
    "4. The information processing apparatus of claim 1, wherein provided that three mutually orthogonal axes of an earphone unit-specific three-dimensional coordinate system are an Xs axis, a Ys axis, and a Zs axis, that mutually orthogonal axes of a three-dimensional coordinate system in which the user is disposed are an Xu axis, a Yu axis, and a Zu axis, in which the Xs axis corresponds to a front and back direction of the earphone unit, the Ys axis corresponds to a top and bottom direction of the earphone, the Zs axis is orthogonal to the Xs axis and the Ys axis, the Xu axis corresponds to a front and back direction of the user, the Yu axis corresponds to a top and bottom direction of the user, and the Zu axis is orthogonal to the Xu axis and the Yu axis, and provided that φ is a tilt angle of the Ys axis with respect to the Yu axis about the Z axis in both coordinate systems, that ψ is a tilt angle of the Ys axis with respect to the Yu axis about the X axis in both coordinate systems, and that θ is a tilt angle of the Xs axis with respect to the Xu axis about the Y axis in both coordinate systems when the user is wearing the earphone unit, the circuitry is further configured to: compute a maximum nodding angle α based on the extremum; compute the angles φ and ψ based on gravitational acceleration and an output of the 3-axis acceleration sensor while the user is in the still state; and compute the angle θ based on the angles φ, ψ, and α as well as the output of 3-axis acceleration sensor when the extremum is detected for the specific axis of the 3-axis acceleration sensor that varies during the nodding gesture.",
    "5. A method comprising: detecting an output from a 3-axis acceleration sensor included in an earphone unit worn by a user while the user is in a still state; monitoring the output of the 3-axis acceleration sensor while a nodding gesture is performed by the user; detecting a time when an angle of the nodding gesture reaches a maximum by detecting an extremum in the output for a specific axis of the 3-axis acceleration sensor that varies during the nodding gesture; and determining, by circuitry, an earphone wearing state based on the output from the 3-axis acceleration sensor in the still state and the output from the 3-axis acceleration sensor at the time of detecting the maximum nodding angle.",
    "6. The method of claim 5, wherein detecting the time when the angle of the nodding gesture reaches the maximum includes detecting a zero-crossing of a gyroscope included in the earphone unit that varies during the nodding gesture.",
    "7. The method of claim 5, further comprising: determining whether the earphone unit is being worn on the user's left ear or right ear based on whether an output corresponding to a specific axis of the 3-axis acceleration sensor that varies during the nodding gesture exhibits convex variation or concave variation.",
    "8. The method of claim 5, wherein provided that three mutually orthogonal axes of an earphone unit-specific three-dimensional coordinate system are an Xs axis, a Ys axis, and a Zs axis, that mutually orthogonal axes of a three-dimensional coordinate system in which the user is disposed are an Xu axis, a Yu axis, and a Zu axis, in which the Xs axis corresponds to a front and back direction of the earphone unit, the Ys axis corresponds to a top and bottom direction of the earphone, the Zs axis is orthogonal to the Xs axis and the Ys axis, the Xu axis corresponds to a front and back direction of the user, the Yu axis corresponds to a top and bottom direction of the user, and the Zu axis is orthogonal to the Xu axis and the Yu axis, and provided that φ is a tilt angle of the Ys axis with respect to the Yu axis about the Z axis in both coordinate systems, that ψ is a tilt angle of the Ys axis with respect to the Yu axis about the X axis in both coordinate systems, and that θ is a tilt angle of the Xs axis with respect to the Xu axis about the Y axis in both coordinate systems when the user is wearing the earphone unit, the method further comprising: computing a maximum nodding angle α based on the extremum; computing the angles φ and ψ based on gravitational acceleration and an output of the 3-axis acceleration sensor while the user is in the still state; and computing the angle θ based on the angles φ, ψ, and α as well as the output of 3-axis acceleration sensor when the extremum is detected for the specific axis of the 3-axis acceleration sensor that varies during the nodding gesture.",
    "9. A non-transitory computer readable medium including computer-program instructions, which when executed by an information processing apparatus, cause the information processing apparatus to: detect an output from a 3-axis acceleration sensor included in an earphone unit worn by a user while the user is in a still state; monitor the output of the 3-axis acceleration sensor while a nodding gesture is performed by the user; detect a time when an angle of the nodding gesture reaches a maximum by detecting an extremum in the output for a specific axis of the 3-axis acceleration sensor that varies during the nodding gesture; and determine an earphone wearing state based on the output from the 3-axis acceleration sensor in the still state and the output from the 3-axis acceleration sensor at the time of detecting the maximum nodding angle.",
    "10. The non-transitory computer readable medium of claim 9, the computer-program instructions causing the information processing apparatus to: detect the time when the angle of the nodding gesture reaches the maximum by detecting a zero-crossing of a gyroscope included in the earphone unit that varies during the nodding gesture.",
    "11. The non-transitory computer readable medium of claim 9, the computer-program instructions causing the information processing apparatus to: determine whether the earphone unit is being worn on the user's left ear or right ear based on whether an output corresponding to a specific axis of the 3-axis acceleration sensor that varies during the nodding gesture exhibits convex variation or concave variation.",
    "12. The non-transitory computer readable medium of claim 9, wherein provided that three mutually orthogonal axes of an earphone unit-specific three-dimensional coordinate system are an Xs axis, a Ys axis, and a Zs axis, that mutually orthogonal axes of a three-dimensional coordinate system in which the user is disposed are an Xu axis, a Yu axis, and a Zu axis, in which the Xs axis corresponds to a front and back direction of the earphone unit, the Ys axis corresponds to a top and bottom direction of the earphone, the Zs axis is orthogonal to the Xs axis and the Ys axis, the Xu axis corresponds to a front and back direction of the user, the Yu axis corresponds to a top and bottom direction of the user, and the Zu axis is orthogonal to the Xu axis and the Yu axis, and provided that φ is a tilt angle of the Ys axis with respect to the Yu axis about the Z axis in both coordinate systems, that ψ is a tilt angle of the Ys axis with respect to the Yu axis about the X axis in both coordinate systems, and that θ is a tilt angle of the Xs axis with respect to the Xu axis about the Y axis in both coordinate systems when the user is wearing the earphone unit, the computer-program instructions causing the information processing apparatus to: compute a maximum nodding angle α based on the extremum; compute the angles φ and w based on gravitational acceleration and an output of the 3-axis acceleration sensor while the user is in the still state; and compute the angle θ based on the angles φ, ψ, and α as well as the output of 3-axis acceleration sensor when the extremum is detected for the specific axis of the 3-axis acceleration sensor that varies during the nodding gesture."
  ],
  "description_excerpt": "1. Field of the Disclosure\n\nThe present disclosure relates to a method of checking the state of how an earphone equipped with a 3-axis acceleration sensor is being worn by a user, and to an audio playback apparatus that uses such an earphone.\n\n2. Description of Related Art\n\nTypically, headphones are used as an apparatus for the purpose of a user converting an audio signal output from an audio playback apparatus into a sound wave (audible sound), basically to listen to music or other such audio alone. The headphones in this specification are connected to such an audio playback apparatus in a wired or wireless manner, and include monaural types which use a single earphone, and stereo types provided with a pair of left and right earphones. An earphone herein refers to the component of headphones worn so as to bring a speaker close to one of the user's ears.\n\nHitherto, technology providing audio-based navigation to pedestrians wearing headphones has been proposed (see Japanese Unexamined Patent Application Publication No. 2002-5675). With this technology, the angle of cranial rotation with respect to the direction in which a user is traveling (the front-to-back direction of the user's body) is computed as follows. Namely, established laser range-finding methods are used to detect the shortest distance from the user's left shoulder to the left side of the headphones, and also to detect the shortest distance from the user's right shoulder to the right side of the headphones.",
  "cpc": [
    "H04R 29/00",
    "H04R 1/1041",
    "H04R 2460/07",
    "H04R 5/033"
  ],
  "ipc": [
    "H04R 29/00",
    "H04R 1/10"
  ],
  "assignees": [
    "Sony Corp",
    "Sony Mobile Communications Inc"
  ],
  "inventors": [
    "Makoto Tachibana",
    "Takashi Shiina",
    "Tetsuya Naruse",
    "Yuichi Shirai",
    "Chikashi YAJIMA",
    "Susumu Takatsuka"
  ],
  "filing_date": "2013-10-02",
  "publication_date": "2016-05-24",
  "grant_date": "2016-05-24",
  "priority_date": "2012-10-02",
  "application_number": "US-201314043957-A",
  "family_id": "50385229",
  "cited_by_count": 14,
  "citations": [
    "JP2002005675A",
    "US20030163287A1",
    "US7825815B2",
    "US20100053210A1",
    "US8472653B2",
    "US20120002822A1",
    "US20110112771A1",
    "US20130307856A1"
  ]
}