SU823864A1 - Method of measuring aircraft flying altitude and/or lay-of-the ground assembly - Google Patents

Description

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The invention relates to geodesy, topography, air navigation and can:. to be used in gravimetry to determine corrections to the results of measuring gravity from aircraft. :

Radiometric and laser methods for determining altitude by sending and receiving radio or optical signals are known.

Some direct readings of radiometric and laernich methods include 0 unknown unknown altitudes of the terrain, therefore, they can only be used for measurements over a calm sea. Over the intersection of the relief, due to its influence by these methods, it has not yet been possible to obtain a satisfactory accuracy in measuring the flight altitude — relative to the initial level surface.

There is also known a method for measuring the flight altitude of aircraft and the height of the terrain along the flight path relative to the Initial level surface by measuring the height of the aircraft relative to the surface relief of the Earth using the parameters of the pressure field 2.

: The disadvantage of this method is that the measurement results strongly depend on the imbalance of its natural baric field and the disturbances of the electric field: Caused by the aircraft, which cannot be taken into account with the necessary precision, ...:

The purpose of the invention is to improve the accuracy of measurements. .

. Delivered: Enna goal is achieved by the fact that in a known method of measuring the height of a flight of aircraft and / or the height of a land terrain along a flight path relatively to the original level of the surface by changing the flight altitude of the aircraft relative to the surface relief of Zetushi, simultaneously with the height the distance is measured up to the surface

0 relief in the direction lying in the vertical plane containing the flight path and making up a non-zero angle with a plumb, the horizontal and vertical projections of this distance are determined according to the measurement results, and the measurement of the height and distance at the subsequent point is performed through the reference time interval corresponding to

If the aircraft passes horizontally a distance equal to the horizontal projection, and the difference between the vertical projection and the height determines the height of the terrain, and the distance between the vertical projection and the height of the next point determines the flight altitude of the aircraft. In addition, for the purpose of continuous measurement, the distance to the surface of the relief is measured several times during the reference time interval, moreover, the time interval between the beginnings of two adjacent measurements is not less than the time required for a single measurement. Consider an example of such a method for determining flight altitude with help. soup altimeter and range finder. FIG. 1 shows a scheme for applying the method; in fig. 2 - c.heme of repeated use of the method. The axis of sight of the altimeter 8 is directed downward along the plumb line, the axis of sight of the range finder t is at an angle OS to it (Fig. 1). At time t, the heights S and the height and distance are determined. By a known distance, its horizontal projection is determined (3 (2. After the aircraft passes the interval of the path (E its end at time tj) height is along ray 0 to site P2, and along ray t is the distance to site Pd. Then the horizontal projection of the distance is calculated, i.e. d23 At the end of the interval dj, height, distance and projection d are measured, and so on This is how measurements are carried out when there is an onboard navigation cHCTefrM to determine horizontal If there is equipment on board for determining course and speed, then measurements are carried out at the ends of time intervals di2. T, tj - t, Tg t, - t, etc., where is the speed. LRH And distances. Knowing these heights and distances, as well as angle, we find the excess iHjj between the sites R., and Р I as the difference of the height Л Р and the vertical projection of the distance, the excess dN.52 between the sites and P P, as the difference in height P2P2 and the vertical projection of the distance. The DN, y.Nu4, etc. are also determined. Then DL2 is exceeded (between points L and L, as the difference in height of the vertical projection of the distance, excess of uh $ between points L. and Lu, as the difference in height and ve), the vertical projection of the distance L, Ld, elevations uh4, etc. . In the general case of elevation between terrain areas, separated by a time interval T, is calculated by the formula H (t + T) t (t) - Ko (t), the elevations between points of the flight by the formula & h. (T + T} t Sg (t T) - Ki, (t), where Sg (t) is the measurement height to the Eimpk surface by the ray at the time instant; the measured is the distance, by the beam 2 at the same MO- time moment; const Kg cos И I-height measured by the beam in through the time interval T after t. To sum up all successively obtained increments of the heights ih and & H, we determine the height of the aircraft at any point of its trajectory relative to the initial level surface and the height of the relief. . Thus, by simultaneously determining the distances and heights from the point of the flight path, the heights of the terrain of the Earth’s surface H (t) are determined, by measuring the distance and height to the same area on the surface from different points of flight at different times. their heights are determined (t}. To make continuous measurements of distance and height: measure a) T much more often than at intervals of the path dj / j .- .. equal to the horizontal projections of the rays J. To do this, at the beginning of the path, the measurements of the distance N and height are conducted with the frequency provided by the speed of the H. 3 meter: -: the second apparatus, and then they are popped at the ends of the intervals d, d2 fdj ,. .. 2), calculated as horizontal projections of the distances measured along the beam, respectively, at points 1, 2 3 (... Fig 2), in the interval d, j, djj, ... (Fig. 1). Gravimetric measurements in motion are very difficult, in particular because of the high level of interference caused by vertical accelerations. On the other hand, knowing the height difference between the points of the flight trajectory, they find the correction for the vertical non-operational accelerations 6 (5, for example, according to the formula) -hl4) hit vrn-MU. 4 × Based on these data, the correction is calculated, for the height, and the elevation correction for the elevations between the terrain relief areas. The application of the method allows to significantly reduce labor costs and reduce the time during gravimetric surveys, especially in hard-to-reach areas: taiga, tundra, desert, - mountains and Tsn .; Due to the possibility of studying the spatial distribution of the gravitational field, it is essential to increase the geological

Claims (1)

Claim The method of measuring the flight altitude of aircraft: and / or the height of the terrain along the flight path relative to the initial level surface by measuring the flight altitude of the aircraft relative to the earth's relief, so that, in order to increase accuracy / at the same time as the height, the distance to the relief is measured in the direction lying in the vertical plane containing the flight path, which makes up a predetermined non-zero angle with a plumb line, and the horizontal and vertical projections of this distances, and the measurement of altitude and distance at a subsequent point is performed through the reference time interval corresponding to the horizontal distance of the aircraft equal to the horizontal projection, and the differences between the vertical projection and height are used to judge the altitude of the aircraft and the height of the terrain.