The invention relates to an inertial measuring device, having an inertial measuring unit for determining a north direction and for determining position angles, having a battery, and having a wireless interface, which inertial measuring device has a housing, in which the inertial measuring unit, the battery and the interface are housed. A carrying handle is provided on the housing, which carrying handle is designed as a one-hand carrying handle such that the inertial measuring device can be carried with only one hand during normal use.

The invention relates to an inertial measuring device, having an inertial measuring unit for determining a north direction and for determining position angles, having a battery, and having a wireless interface, which inertial measuring device has a housing, in which the inertial measuring unit, the battery and the interface are housed. A carrying handle is provided on the housing, which carrying handle is designed as a one-hand carrying handle such that the inertial measuring device can be carried with only one hand during normal use.

A gyrocompass includes: a binnacle; a gyro case having a gyro rotor; a vertical ring mounted on the binnacle for rotation about a vertical axis, the vertical axis extending perpendicular to a gimbal axis and a horizontal axis, the gimbal axis extends in a direction of a spin axis of the gyro rotor and the horizontal axis extends perpendicular to the gimbal axis and parallel to a horizontal plane; a horizontal ring supported by the vertical ring for rotation about the gimbal axis and supporting the gyro case for rotation about the horizontal axis or supported by the vertical ring for rotation about the horizontal axis and supporting the gyro case for rotation about the gimbal axis; a horizontal servo motor for rotating the gyro case about the horizontal axis; and an azimuth servo motor mounted on the vertical ring for rotating the vertical ring about the vertical axis.

A gyrocompass includes: a binnacle; a gyro case having a gyro rotor; a vertical ring mounted on the binnacle for rotation about a vertical axis, the vertical axis extending perpendicular to a gimbal axis and a horizontal axis, the gimbal axis extends in a direction of a spin axis of the gyro rotor and the horizontal axis extends perpendicular to the gimbal axis and parallel to a horizontal plane; a horizontal ring supported by the vertical ring for rotation about the gimbal axis and supporting the gyro case for rotation about the horizontal axis or supported by the vertical ring for rotation about the horizontal axis and supporting the gyro case for rotation about the gimbal axis; a horizontal servo motor for rotating the gyro case about the horizontal axis; and an azimuth servo motor mounted on the vertical ring for rotating the vertical ring about the vertical axis.

There is provided an information processing apparatus that is able to more accurately detect an azimuth during traveling of a mobile object. The information processing apparatus includes a north-seeking process controller that performs a north-seeking process on a basis of, among pieces of information related to a mobile object, at least two pieces of information, in which orientations of the mobile object at respective timings when the at least two pieces of information are measured by an inertial measurement unit are different from each other, and at least one of the at least two pieces of information measured by the inertial measurement unit is measured while the mobile object is traveling.

A cavity sensor including: a body defining a cavity, the cavity having an opening on one end and a closed surface on other end; a reflective surface disposed in the cavity, the reflective surface being angled 45 degrees relative to a propagation direction of an incoming wave through the opening; and first and second angle probes positioned on each of two ends of the reflective surface. Also provided is a cavity sensor including: a body defining a cavity, the body having two or more conduits, each having an opening, the body having a closed surface opposing the openings, and a probe positioned in the cavity at a position common to each of the two or more conduits.

A cavity sensor including: a body defining a cavity, the cavity having an opening on one end and a closed surface on other end; a reflective surface disposed in the cavity, the reflective surface being angled 45 degrees relative to a propagation direction of an incoming wave through the opening; and first and second angle probes positioned on each of two ends of the reflective surface. Also provided is a cavity sensor including: a body defining a cavity, the body having two or more conduits, each having an opening, the body having a closed surface opposing the openings, and a probe positioned in the cavity at a position common to each of the two or more conduits.

Method for operation of a strap-down ship's gyro compass for optimal calculation of position and course angle on a ship, with three rotational rate sensors each mutually aligned to each other at a right angle, and two nominally horizontally aligned orthogonal acceleration sensors, without required specification of the geographic latitude and/or of the speed of the ship, characterized by the steps: a. Preparation of a set of dynamic equations based on the angular velocity components detected by the rotational rate sensor, b. Preparation of a measured data equation based on the force components detected by the acceleration sensors, c. Determination of the properties of the lever arm between the strap-down ship's gyro compass and the point of rotation of the ship, and d. Determination of the properties of the earth's rotation and of the ship's angular velocity, wherein their properties are determined on the basis of the set of dynamic equations and the measured data equation, and are used in each case as parameters for calculation of the geographic latitude and/or speed of the ship.

Method for operation of a strap-down ship's gyro compass for optimal calculation of position and course angle on a ship, with three rotational rate sensors each mutually aligned to each other at a right angle, and two nominally horizontally aligned orthogonal acceleration sensors, without required specification of the geographic latitude and/or of the speed of the ship, characterized by the steps: a. Preparation of a set of dynamic equations based on the angular velocity components detected by the rotational rate sensor, b. Preparation of a measured data equation based on the force components detected by the acceleration sensors, c. Determination of the properties of the lever arm between the strap-down ship's gyro compass and the point of rotation of the ship, and d. Determination of the properties of the earth's rotation and of the ship's angular velocity, wherein their properties are determined on the basis of the set of dynamic equations and the measured data equation, and are used in each case as parameters for calculation of the geographic latitude and/or speed of the ship.

A method of determining a reference direction for an angular measurement device, comprising: providing a rigid structure having an antenna for a global navigation satellite system (GNSS) fixed at a first point thereof; fixing the angular measurement device to a second point on the rigid structure, separated from the first point by at least 0.5 meters; while rotating the rigid structure so as to cause rotational movement of the antenna around the sensitive axis, acquiring velocity measurement data from the GNSS and angular velocity measurement data from the angular measurement device; and using the velocity measurement data and the angular velocity measurement data to determine a reference direction for the angular measurement device.