著者

佐藤 清秀 内山 晋二 山本 裕之

出版者

特定非営利活動法人 日本バーチャルリアリティ学会

雑誌

日本バーチャルリアリティ学会論文誌 (ISSN:1344011X)

巻号頁・発行日

vol.10, no.3, pp.391-400, 2005-09-30 (Released:2017-02-01)

被引用文献数

3

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This paper describes a new robust registration framework, which is named "UG+B", for Augmented or Mixed Reality (AR/MR) applications. Our methods measure pose of a head-mounted display (HMD) using not only an image captured by a user's view camera mounted on the HMD, but also images captured by bird's-eye view cameras each of which observes the HMD from a third-person's viewpoint, as well as an orientation measured by a sensor mounted on the HMD. In our methods, the markers placed in the scene and that on the HMD are tracked on the user's view and the bird's-eye view image respectively. Then, the pose of the HMD is estimated to minimize the sum of the re-projection error for all markers. Furthermore, the inclination angles measured by the orientation sensor are used as known values to constrain the pose, thus, the remaining parameters, i.e. the position and azimuth angle, are deduced by image information. In addition to theoretical discussions, this paper demonstrates the effectiveness of our methods by experiments in comparison with conventional vision-based registration methods.

著者

菊川 信吾 磯村 悟 岩田 聡 塩見 繁 内山 晋

出版者

The Magnetics Society of Japan

雑誌

日本応用磁気学会誌 (ISSN:02850192)

巻号頁・発行日

vol.7, no.2, pp.83-86, 1983

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New bubble garnet films with orthorhombic anisotropy, (YTmGdBi)₃(FeGa)₅O₁₂, (YTmEuBi)₃(FeGa)₅O₁₂, (YTmSmBi)₃(FeGa)₅O₁₂ and (YTmLaBi)₃(FeGa)₅O₁₂, have been epitaxially grown on (110) GGG substrates. Although a large in-plane anisotropy <i>K</i>_p of 2∼4×10⁴ erg/cm³ is induced in YTmEu and YTmSm films, the uniaxial anisotropy <i>K</i>_u obtained is not large enough to be used for bubble materials. In YTmGd and YTmLa films, <i>K</i>_u is of almost the same magnitude as <i>K</i>_p with a value of 1.0∼1.5×10⁴ erg/cm³. The wall dynamics has been investigated by stripe domain transport method. For YTmLa films, the wall mobility μ is ∼22 m/sOe, the peak velocity <i>V</i>_p is ∼120 m/s and the coercive force <i>H</i>_c is ∼0.7Oe. These characteristics may be useful for current access devices.

著者

佐藤 靖之 浜本 正人 S. シュパイデル 岩田 聡 内山 晋

出版者

The Magnetics Society of Japan

雑誌

日本応用磁気学会誌 (ISSN:02850192)

巻号頁・発行日

vol.10, no.2, pp.133-136, 1986

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It is found that a large orthorhombic anisotropy is induced in (EuBi)₃Fe₅O₁₂ garnet films grown on (110) NdGG substrates. The Bi content is controlled by controlling the melt composition and the supercooling temperature. Gyorgy's parameter <i>B</i>=−2(<i>K</i>_u+<i>K</i>_p) increases linearly with the Bi content. The main part of <i>B</i> is found to be growth-induced. Gyorgy's parameter <i>A</i>=<i>K</i>_p−<i>K</i>_u is very small and almost independent of the Bi content. The growth- and stress-induced parts of <i>A</i> are found to be considerably large, but of opposite sign, and to compensate each other nearly completely, although their respective absolute values increase with increasing Bi content.<br>Magnetic properties of a (Eu_1.8 Bi_1.2) Fe₅O₁₂ film are obtained as follows: saturation magnetization 4π<i>M</i>_s = 1560 Gauss, uniaxial anisotropy <i>K</i>_u = 1.6 × 10⁵erg/cm³, in-plane anisotropy <i>K</i>_p = 1.6 × 10⁵erg/cm³, quality factor <i>Q</i> = 1.7, material length <i>l</i> = 0.06 μm and wall mobility μw = γ<i>Δ₀/<i>α</i> = 19 ms^-1. Such a film might be used as a 0.5 μm bubble material for current access devices.

著者

小竹 大輔 佐藤 清秀 内山 晋二 山本 裕之

出版者

特定非営利活動法人 日本バーチャルリアリティ学会

雑誌

日本バーチャルリアリティ学会論文誌 (ISSN:1344011X)

巻号頁・発行日

vol.13, no.2, pp.183-193, 2008

被引用文献数

2

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We propose a hybrid camera pose estimation method using an inclination sensor and line segments. While our method does not require any prior information on the camera pose and the correspondences between 2D and 3D line segments, it can calculate the camera pose fast using the two-step algorithm that calculates azimuth first and then position under the inclination constraint obtained from the sensor. These features meet the requirement of initialization for edge-based registration used in mixed reality (MR) systems. This paper describes the details of the method and shows its effectiveness with experiments in which the method is used in an actual MR application.