Method for determining north direction by means of north-seeking gyroscope

摘要

1. A method of determining the north direction by means of a north-seeking gyroscope containing, in an inner frame, a gyroscope motor with a spin axis which can be aligned horizontally, an outer frame or pendulum member in which the inner frame is disposed for rotation about an axis of rotation which can be aligned vertically, a verticality device for the vertical alignment of the rotatable pendulum member which is suspended in a housing, particularly by means of a universal joint, a restraining device with a signal producing pick-up for the angular position of the inner frame in relation to the pendulum member with respect to a preset zero angular position and a torque producer, controlled by the pick-up signal, to restrain the inner frame in its zero angular position, the current in the torque producer representing a measure of the moment driving the spin axis of the gyroscope towards the north and caused by the input angular velocity, and a regulating element, particularly a stepping motor, which causes a rotation of the pendulum member in relation to the housing with reference to a preset zero rotation, this housing comprising a zero mark for determination of the north direction, this is to say of the angle gamma existing between the zero mark and north, characterised in that, in order to determine the angle gamma, at least three measurements of an output quantity ~Xi depending on the input angular velocity omega are carried out in different positions of the pendulum member, turned through defined angles alpha i in relation to the zero rotation, and that the angle gamma is calculated from the equations ~Xi = K [OMEGA H sin (gamma + alpha i ) + D], in which OMEGA H is the horizontal component of the speed of rotation of the earth, D is the gyroscope drift and K is the scale factor.