Patent ID: 8405611
Filing Date: 2013-03-26
Classification: A63F,G06F

Abstract:
1. An orientation calculation apparatus for obtaining data from an input device including at least an angular rate sensor and an acceleration sensor, and calculating a three dimensional orientation of the input device in a three-dimensional space, the apparatus comprising: a processor; a memory coupled to said processor, said memory storing instructions that, when executed by said processor, control said processor to: calculate data of the three-dimensional orientation of the input device in accordance with an angular rate detected by the angular rate sensor; calculate a three-dimensional acceleration vector providing orientation information for the input device in accordance with acceleration data from the acceleration sensor; calculate an acceleration projection vector projected onto a plane perpendicular to a predetermined axis, wherein the predetermined axis corresponds to a direction in which the input device is oriented as detected by the angular rate sensor; calculate a projection gravity vector which corresponds to the projection of a vertically downward direction onto the plane; and correct the data of the three-dimensional orientation of the input device such that a direction of the three-dimensional acceleration vector in the three-dimensional space approaches the vertically downward direction in the three-dimensional space, wherein, the data of the three-dimensional orientation of the input device is corrected so as to at least rotate the three-dimensional orientation of the input device about the predetermined axis in such a direction that a direction of the acceleration projection vector approaches a direction of the projected gravity vector.