Patent ID: 11953325
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 7:
8. A direction calculation method in which a direction calculation apparatus calculates a direction to be presented to a guided person as a presented direction using a force sensation presentation device gripped by the guided person, the direction calculation method comprising:
acquiring, by the direction calculation apparatus, using a geomagnetic map including a bias of an azimuth angle caused by geomagnetic distortion at a position included in a predetermined range, from a current position of the force sensation presentation device, a bias of the azimuth angle, wherein the bias of the azimuth angle is caused by geomagnetic distortion at the current position;
acquiring, by the direction calculation apparatus, a first azimuth angle, wherein the first azimuth angle indicates an azimuth of the force sensation presentation device, and the azimuth is not taking into account an influence of geomagnetic distortion in a reference coordinate system at the current position; and
calculating, by the direction calculation apparatus, using the bias and the first azimuth angle, from a first instructed force sensation vector in a reference coordinate system indicating a direction to be instructed to the force sensation presentation device, a second instructed force sensation vector in a force sensation presentation device coordinate system as the presented direction, wherein the presented direction indicates a direction to be instructed to the force sensation presentation device.