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

Claim 6:
7. 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 geomagnetic vector and a gravitational acceleration vector of a reference posture of a force sensation presentation device in a reference coordinate system at a position included in a predetermined range, from a current position of the force sensation presentation device, a first matrix, wherein the first matrix comprises a geomagnetic vector, a gravitational acceleration vector, and an outer product vector of the geomagnetic vector and the gravitational acceleration vector of the reference posture of the force sensation presentation device in the reference coordinate system at the current position;
acquiring, by the direction calculation apparatus, a second matrix, wherein the second matrix comprises a geomagnetic vector, a gravitational acceleration vector, and an outer product vector of the geomagnetic vector and the gravitational acceleration vector of a current posture of the force sensation presentation device in the reference coordinate system at the current position; and
calculating, by the direction calculation apparatus, using the first matrix and the second matrix, 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.