Abstract:
The present invention provides a device and method for estimating a travel direction of a moving body, the device and method allowing highly accurate estimation of the travel direction even in the case where the positional relationship between the moving body and the self-contained sensing device or the posture is changed freely.The travel direction estimating device includes (i) a gravitational direction vector estimating section 2407 for estimating a gravitational direction vector on the basis of respective outputs of an acceleration sensor and an angular velocity sensor, (ii) a tentative travel direction vector generating section 2413 as a candidate of travel direction vector, (iii) a walk frequency estimating section 2424 for estimating a walk frequency from component data resulting from projecting acceleration component data for the gravitational direction vector, and (iv) a travel direction vector determining section 2425 for determining an objective function and a phase difference on the basis of a frequency component of a component Af resulting from projecting the acceleration component data for a travel direction vector, a frequency component of a component An resulting from projecting the acceleration component data for a side-to-side direction vector, a frequency component of a component Ws resulting from projecting angular velocity component data for the travel direction vector, a frequency component of a component Wn resulting from projecting the angular velocity component data for the side-to-side direction vector, a walk frequency, and the phase of the walk frequency, selecting as travel direction vectors, tentative travel direction vectors with which the phase difference is within a predetermined range and each of which maximizes the value of the objective function, and determining the side of the travel direction.
Abstract:
The present invention provides a device and method for estimating a travel direction of a moving body, the device and method allowing highly accurate estimation of the travel direction even in the case where the positional relationship between the moving body and the self-contained sensing device or the posture is changed freely.The travel direction estimating device includes (i) a gravitational direction vector estimating section 2407 for estimating a gravitational direction vector on the basis of respective outputs of an acceleration sensor and an angular velocity sensor, (ii) a tentative travel direction vector generating section 2413 as a candidate of travel direction vector, (iii) a walk frequency estimating section 2424 for estimating a walk frequency from component data resulting from projecting acceleration component data for the gravitational direction vector, and (iv) a travel direction vector determining section 2425 for determining an objective function and a phase difference on the basis of a frequency component of a component Af resulting from projecting the acceleration component data for a travel direction vector, a frequency component of a component An resulting from projecting the acceleration component data for a side-to-side direction vector, a frequency component of a component Ws resulting from projecting angular velocity component data for the travel direction vector, a frequency component of a component Wn resulting from projecting the angular velocity component data for the side-to-side direction vector, a walk frequency, and the phase of the walk frequency, selecting as travel direction vectors, tentative travel direction vectors with which the phase difference is within a predetermined range and each of which maximizes the value of the objective function, and determining the side of the travel direction.
Abstract:
An angle offset judging device (1) includes: an azimuth histogram generating section (126) for obtaining an appearance frequency of estimated azimuths; and an evaluating section (127) for making an evaluation of whether or not the appearance frequency thus obtained shows a tendency which is observed in a case where an azimuth is properly estimated under a binding condition concerning an advancing direction of a movement of a moving body.
Abstract:
The present invention provides a device and a method which allow a travel direction of a moving body to be estimated more efficiently. The present invention provides a travel direction estimating device for estimating a traveling direction in which a moving body travels, including: an accelerometer for detecting an acceleration by which the moving body travels; an angular velocity sensor for detecting an angular velocity by which the moving body travels; and a travel direction vector determining section for determining the traveling direction of the moving body by calculating, based on the acceleration detected by the accelerometer and on the angular velocity detected by the angular velocity sensor.
Abstract:
An object of the present invention is to provide an altitude measurement system and an altitude measurement method capable of measuring an altitude of a moving body in a stand-alone mode. In order to achieve the present object, the invention provides an altitude measurement system having altitude measurement terminals M1 to Mn connected to the Internet connection and atmospheric-pressure trend management unit TM1 connected to the Internet connection, each of the altitude measurement terminals M1 to Mn including: an atmospheric-pressure measurement unit 201 that measures an atmospheric pressure; a same-floor-stay detection unit 202 and an in-area-stay detection unit 203 for detecting existence of the moving body at a predetermined altitude; and an atmospheric-pressure trend candidate value output unit 204 that outputs, to the atmospheric-pressure trend management unit TM1, atmospheric pressure data measured during a predetermined period by the atmospheric-pressure measurement unit 201 when the existence of the moving body exists at a predetermined altitude, and an atmospheric-pressure trend integration/generation unit 205 generating the reference atmospheric pressure data corresponding to the altitude by, as needed, calculating an average value among a plurality of pieces of the atmospheric pressure data supplied from the atmospheric-pressure trend candidate value output unit 204.