Orientation angle detector
AssigneeNEC Tokin Corporation
InventorsHiroshi Abe, Kazutake Muto
Life of this patent
Estimating the term…
Abstract
An orientation angle detector using gyroscopes (301-303) for detecting X-, Y- and Z-angular velocities which are time-integrated (60) to produce pitch, roll and yaw angles (γ, β, α) of the orientation. Two accelerometers (403, 404) are used to obtain tentative pitch and roll angles in order to correct the pitch and roll angles, and two terrestrial magnetometers (401, 402) are used to obtain a tentative yaw angle so as to correct the yaw angle. When the tentative pitch, roll and yaw angles are defined accurate (50), the integrated pitch, roll and yaw angles are corrected (60) by the tentative pitch, roll and yaw angles.
Claims64
An orientation angle detector comprising:
- a plurality of gyroscopes (301-303) disposed in parallel with a plurality of orthogonal axes (Xs-Zs) defining a detector co-ordinate on said detector, respectively, for measuring angular velocities (Jx, Jy, Jz) around respective axes (Xs-Zs),
- a motion angle calculator (310) coupled to said plurality of gyroscopes (301-303) for calculating a motion angle (ΔX, ΔY, ΔZ) from said angular velocities (Jx, Jy, Jz),
- at least one accelerometer (403, 404) disposed in parallel with at least one of said orthogonal axes (Xs-Zs) for measuring linear acceleration (Ax, Ay),
- a static angle calculator (405) coupled to said at least one accelerometer (403, 404) for calculating a static angle (R, P) from said acceleration (Ax, Ay), and
- an orientation angle calculator (60) coupled to said motion angle calculator (310) and said static angle calculator (405) for integrating said motion angle (ΔX, ΔY, ΔZ) to an integrated angle and calculating an orientation angle (α, β, γ) from said integrated angle, said static angle (R, P) and an azimuthal deviation angle (Φ),
- wherein said orientation angle (α, β, γ) is an angular difference between said detector co-ordinate (Xs-Ys-Zs) and a reference co-ordinate (X-Y-Z) in a space including said detector,
- wherein two magnetometers (401, 402) are disposed in parallel with two of said plurality of orthogonal axes (Xs, Ys) to measure terrestrial magnetic components (Mx, My) in the two of said plurality of axes (Xs, Ys), and
- wherein said static angle calculator (405) is coupled to said two magnetometers (401, 402) for calculating an azimuth from said terrestrial magnetic components (Mx, My) to produce from said azimuth said azimuthal deviation angle (Φ) from said reference co-ordinate (X-Y-Z) as an additional factor of said static angle (R, P).
Dependencies are inferred from the claim text.