Electronic tilt measuring system

Details Electronic tilt measuring system Electronic tilt measuring system

1991-07-12

1993-03-09

Haroian, Harry N.

Geometrical instruments

Indicator of direction of force traversing natural media

Level or plumb, terrestrial gravitation responsive

33228, 33301, G01C 906

Patent

active

051917130

DESCRIPTION:

BRIEF SUMMARY
The invention relates to means for measuring the relative tilt of a number of platforms to a nominated datum plane, for example for weapon platforms on board a floating ship.
For a ship weapon system to detect, locate, identify, engage and destroy a target successfully, it is fundamental that the initial alignment of all the weapon and sensor platforms is correct. Thus, a system is required that is capable of accurately measuring the relative tilts between equipment platforms on a floating ship. Furthermore, since work is carried out through all the stages of a warship's life, by shipbuilders and dockyards, it is necessary to be able frequently to measure and correct relative tilts between equipment platforms with respect to the ship's Master Level Datum. If a relative tilt exists between equipments, errors in elevation and training of the weapons result.
The tilt of weapon equipments is defined as the angle by which their planes of rotations are tilted relative to each other, or to the ship's Master Level Datum. This datum platform is usually sited near the neutral pitch and roll axes of the ship and parallel to the calculated water line. The magnitude of the tilt is defined as the maximum inclination of the equipment seating relative to the plane of the datum platform and the direction in which this occurs with respect to the ship's fore and aft line (e.g. 1.5 minutes of arc at a bearing of 45.degree. to Port).
If a relative tilt exists between equipments, the errors resulting in the weapon alignments vary depending on the elevation and bearing of the equipments. When the equipment is trained to the tilt relative bearing, the elevation error is a maximum and equal to the tilt angle whilst the training error is zero and, when the equipment is trained at right angles to the tilt relative bearing, the elevation error is zero whilst the training error is proportional to the tangent of the elevation angle of the equipment. As the equipment elevates this training error increases, equalling the tilt angle at an elevation of 45.degree. and becoming more pronounced at higher elevations. For bearings other than those along or normal to the tilt relative bearing, errors exist in both elevation and training.
To achieve desirable system accuracies it is necessary to reduce the relative tilt angles between equipments to within prescribed limits, either by mechanical or computer software corrections. This particularly applies to equipments capable of high angles of elevation.
The conventional technique for measuring weapon platform tilts used by dockyards and shipbuilders requires the ship to be positioned in dock, breast-shored in a stable position, but still just waterborne, before commencing a tilt test. This is necessary to restrict the motion of the ship to enable measurements to be taken using bubble type clinometers. The loading of the ship must be as near as possible to sea-going conditions and any movement on board must be kept to a minimum. Tilt rings, (for platform adjustments) are set to zero if they are fitted.
A 6.degree. bubble type clinometer is set initially parallel to the fore and aft line of the ship on a convenient rigid position on each equipment under test. Each clino is placed on a special 3.degree. wedge to ensure that all readings throughout the test are positive.
A master clino is set up on a portable turntable, which is sited in a suitable ship position where communications are available to all weapon platform stations under test and which is levelled to the horizontal plane.
The portable turntable is trained from 0.degree. to 360.degree. in 10.degree. steps, at the same time as the equipment under test. For each 10.degree. step the operator at the master position first adjusts his clino until the bubble is central. He then presses a bell push which rings a bell at all remote stations, to enable the clino readers at the platform stations to adjust their clinos until all bubbles are synchronised with the master. Any movement in the ship during this period necessitates a repeat of the exercise

REFERENCES:
patent: 3851399 (1974-12-01), Edwards
patent: 4277895 (1981-07-01), Wiklund
patent: 4486844 (1984-12-01), Brunson et al.
patent: 4531299 (1985-07-01), Wolfe et al.

Affiliated with

Also associated with

Rating

Electronic tilt measuring system does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Electronic tilt measuring system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic tilt measuring system will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-203830