WO2002027259A2

WO2002027259A2 - Method and apparatus for the precise alignment of a weapon relative to a sight

Info

Publication number: WO2002027259A2
Application number: PCT/US2001/029993
Authority: WO
Inventors: Moshe Blau
Original assignee: C.I. System Ltd.; Friedman, Mark, M.
Priority date: 2000-09-29
Filing date: 2001-09-26
Publication date: 2002-04-04
Also published as: AU2001293081A1; WO2002027259A3

Abstract

The present invention relates to a method and apparatus for remote boresighting a large caliber gun (14) by electro-optical means, while a single user performs the alignment in close proximity to the sight (18) of a weapons platform carrying the gun. A remote boresight (10) comprised of an imager, which includes a TV camera, is attached either internally or externally to the gun (14), and used to relay a target image to the single user. The user views the same target through the sight (18) and brings the sight and the gun into alignment.

Description

METHOD AND APPARATUS FOR THE PRECISE ALIGNMENT OF A WEAPON RELATIVE TO A SIGHT

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to the subject of aligning a firearm with respect to a fire control system or a sight, a procedure widely known as "boresighting", to increase the hit probability and accuracy of the firearm. More specifically the present invention relates to an apparatus and method for remote boresighting a large caliber gun by electro-optical means, where a single user performs the alignment in close proximity to the fire control system or the sighting system (referred to hereafter generically as a "sight") of a weapons platform carrying the gun, for example a main battle tank or an armored personal carrier.

Modern line-of-sight weapons are required to satisfy a high hit probability with the first shot. The precise alignment of a firearm to its sight is crucial for achieving a high hit probability and accuracy. At present, particularly in large caliber, direct fire weapons such as tanks or armored vehicle guns, referred to hereafter as "tank" guns, this alignment is done by two soldiers: a first soldier who views the target through a device which normally includes a telescope mounted in the tank gun's muzzle, and a second soldier (the "gunner") who aims his sight at the same target. The first soldier then signals to the second, using for example hand gestures, to position the tank gun so that the telescope line-of-sight coincides with the target, while the second soldier centers his sight on the same point. This procedure is cumbersome, complex, time-consuming and at times exposes the first soldier to danger, since he must stand outside the tank or armored vehicle. Moreover, since it is preferable to boresight a weapon often in order to increase the hit accuracy and probability, the limitations cited above are even more critical.

The use of two soldiers as described above remains universally the method of choice in large caliber weapon boresighting. However, some novel aiming procedures use some elements of the present invention described below, in particular electro-optical imaging elements. For example, US patent 4,936,190 describes an electrooptical muzzle sight used to aim a gun during the firing process. An aiming device permanently attached to the muzzle includes a CCD camera as does the present invention, thus allowing one instead of two users to aim and fire the gun. However this device is used to replace the gunner sight and not for alignment or boresighting procedures between the gunner sight and the gun muzzle axis. US patent 5,711,104 describes a small arm visual aiming system and a method for aiming a firearm. Here too, a device including a CCD is used not to boresight the gun to the sight prior to firing the gun at a target, but to aim the firearm during the firing process and to prevent exposing the user to an enemy. This device, while permanently attached to a muzzle is useful only for small firearms, and not for large caliber guns.

The remote boresighting procedure of the present invention is essentially different from fire control alignment procedures between a gunner sight and an external (to a tank) remote target acquiring element such as a TV camera, as disclosed for example in US Pat. 4,318,330. The latter procedures do not solve the basic problem of boresighting, which is ensuring alignment between the gunner sight and the gun line-of-fire (or muzzle axis). In US Pat. 4,318,330, the TV camera is fixedly mounted on the turret, remote from the gun's muzzle and there is no assurance that the camera and the gun remain aligned. In fact, in configurations such as that of US pat. 4,318,330, thermal expansion of the gun during and after firing degrades the alignment between camera and gun, requiring repeated boresighting procedures to align the camera with the gun, before the TV camera can be used again for fire control. In turn, the boresighting is invariably carried out by the conventional means, with all their limitations and disadvantages.

Thus none of the inventions in prior art solve the problem of needing a crew of two to perform a boresighting procedure of a large caliber weapon in sometimes dangerous circumstances.

There is thus a recognized need for, and it would be advantageous to have, a method and an apparatus for the precise alignment of a weapon, particularly a tank gun, relative to a sight, which is devoid of the above limitations. The present invention provides such a method and apparatus, which is simpler, less time consuming, more accurate and safer by not requiring one soldier to stand outside the armored vehicle. Boresighting of a large caliber weapon according to the present invention can be done frequently, at day and at night, thus preserving a high hit accuracy and high first hit probability.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an improved boresighting, by enabling a gunner to point the gun to a target of his choice by himself, without the need for another crew member to help him.

Another object of the present invention is to increase the alignment accuracy, by allowing the gunner to pick a target that is clearly the target he is pointing his fire control system at, and by providing him an unambiguous identification of this target

A further object of the present invention is to shorten the time it takes to perform the alignment, and by allowing it to be performed frequently, day and night

A still further object of the invention is to make the alignment procedure safer by not requiring a crew member to be outside the armored vehicle or tank when performing the boresighting.

According to the present invention there is provided a method by which a precise alignment of a gun relative to a sight is performed by a single user, comprising the steps of: a) attaching a boresight to the gun, the boresight including an electro-optic imaging device; b) acquiring an image of the target through the boresight; c) transmitting the image to a remote display positioned in proximity to the sight; d) viewing the target through the sight; and e) aligning the image with the target viewed through the sight.

According to one feature of the method of the present invention, the attaching includes inserting the boresight inside a muzzle of the gun.

According to another feature of the method of the present invention, the attaching includes permanently attaching the boresight externally to the gun.

According to yet another feature of the method of the present invention, the acquiring includes acquiring a video image. According to yet another feature of the method of the present invention, the attaching renders parallel a longitudinal axis of the boresight and a longitudinal axis of the gun.

According to yet another feature of the method of the present invention, the transmitting is effected via a hardwired link between the imaging device and the display.

According to yet another feature of the method of the present invention, the transmitting is effected via a wireless transmission.

According to yet another feature of the method of the present invention, the aligning further includes superimposing a cross hair on the video image.

According to yet another feature of the method of the present invention, the cross hair is provided electronically.

According to the present invention there is provided an apparatus for the precise alignment of a gun relative to a sight, the gun having a muzzle, comprising: a) a boresight operative to be secured to the gun, the boresight including an electro-optic imaging device for acquiring an image of a target; and b) a remote display for displaying the target.

According to one feature of the apparatus of the present invention, there is provided a mechanism for transmitting the image from the imaging device to the remote display.

According to another feature of the apparatus of the present invention, there is provided a mechanism for superposing a cross hair on the image.

According to yet another feature of the apparatus of the present invention, the mechanism for transmitting includes a wireless mechanism.

According to yet another feature of the apparatus of the present invention, the mechanism for transmitting includes a hardwired link.

According to yet another feature of the apparatus of the present invention, the mechanism for superposing generates the cross hair electronically.

According to yet another feature of the apparatus of the present invention, the boresight is operative to be reversibly secured to the gun.

According to yet another feature of the apparatus of the present invention, the boresight is operative to be reversibly inserted in the muzzle. According to yet another feature of the apparatus of the present invention, the boresight is fixedly attached to the gun.

The present invention successfully addresses the shortcomings of the presently known configurations by providing a method and an apparatus for the precise alignment of a weapon relative to a sight or fire control system, which is simpler, less time consuming, more accurate and safer by not requiring one soldier to stand outside an armored vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice. In the drawings:

FIG. 1 illustrates a tank with a removable boresight mounted inside the muzzle of the gun;

FIG. 2 illustrates a tank with a fixed boresight mounted externally on the muzzle;

FIG. 3 depicts schematically one embodiment of the boresight of the present invention;

FIG. 4 depicts schematically another embodiment of the boresight of the present invention;

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The principles and operation of a method and an apparatus for the precise alignment of a weapon relative to a sight or fire control system according to the present invention may be better understood with reference to the drawings and accompanying descriptions.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. Referring now to the drawings, FIG.l illustrates one embodiment of a removable "internal" boresight 10 that is mounted inside a muzzle 12 of a weapon or gun 14 of a main battle tank 16. "Weapon" and "gun" are used interchangeably throughout this specification. Boresight 10 fits snugly inside muzzle 12, and may be inserted and removed easily, as well known in the art. Boresight 10 enables a user such as the gunner of tank 16 to align a sight 18 having a gunner line-of-sight 20 with respect to a gun muzzle axis 22 on a target 24. Sight 18 is operated from inside tank 16, so that the gunner is protected. When the alignment is completed, boresight 10 is dismantled from gun 14 and is stored until the next time the alignment is to be performed. Muzzle 12 where boresight 10 is mounted is where a shell or other projectile emerges from the barrel of gun 14, and governs the initial velocity direction of the projectile in its trajectory. In the boresighting procedure, gun muzzle axis 22 and gunner line-of-sight 20 meet at the same point on target 24, or in other words, the weapon (gun 14) is aligned with (or relative to) sight 18.

FIG. 2 shows an embodiment of a fixed "external" boresight 10', mounted externally on gun 14 at muzzle 18. The mounting may be done using any type of mechanical means 30 which secure boresight 10' to gun 14, for example screws or clamps or other means well known in the art, and which ensure that a boresight line-of-sight 26 of boresight 10' is parallel to gun muzzle axis 22. For a target far enough from the tank, boresight line-of-sight 26 and muzzle axis 22 indicate the same point. Since boresight 10' normally remains permanently attached to gun 14, including when gun 14 is fired, mechanical means 30 have to impart rigidity and maintain alignment of the combined boresight-gun assembly. In the boresighting procedure, the line extending from boresight line-of-sight 26 meets gunner line-of-sight 20 on the same point on target 24. The combined boresight-gun assembly alignment is maintained by periodical alignment checks, which are carried out much less frequently than the regular boresighting procedure. These checks verify that gun muzzle axis 22 remains parallel with boresight line-of-sight 26. A typical alignment check includes the use of an internal boresight 10 inside muzzle 12, and its alignment with external boresight 10'. To make sure that internal boresight 10 is aligned with gun muzzle axis 22, boresight 10 is rotated inside muzzle 12, and a check is made that a cross-hair which is normally part of, and visible through the boresight telescope, remains fixed on the same point of a target. Once the alignment between boresight 10 and gun muzzle axis 22 is established, the alignment check between boresights 10 and 10' assures the alignment of boresight 10' (or equivalently its line-of-sight 26) and gun muzzle axis 22. After achieving this alignment, boresight 10 is removed, leaving boresight 10' aligned with gun 14.

The information obtained by boresights 10 or 10', has to be processed and transmitted to the gunner who is physically remote from the boresight, and physically close to sight 20. The boresight of the present invention, whether internal or external, is therefore a "remote" boresight equipped with elements that provide the "remote" operation function, in addition to the usual, known in the art telescope. FIG. 3 shows details of internal boresight 10 in a longitudinal cross section. Boresight 10 typically comprises a mechanical interface section 100 and an imaging section 102, the latter referred to hereafter as "imager" 102. In use, the imaging section points toward the target. Preferably, imager 102 includes a telescope 104, an imaging device 106, such as a TV or CCD camera, positioned at the focal plane of telescope 104, and transmission means to transmit the images acquired by device 106 so that they may be viewed by the remote gunner. Preferably, such transmission means include a transmitter 108 and associated electronics to transmit the video signal to a monitor 112 inside tank 16, shown in FIGS. 1 and 2, either by using a hardwired link 110, or by using a wireless transmission mechanism. As mentioned above, telescope 104 normally has a cross-hair. A cross-hair can also be imposed electronically on the video signal of the target, so that the target image seen on monitor 112 includes the cross-hair. The cross hair can be adjusted horizontally and vertically by the user to generate a line-of-sight that is parallel to the gun muzzle axis.

As shown in FIG. 4, imager 102 preferably also includes night- vision elements 114 to generate a video image in the dark, for example an image intensifier or infrared imaging elements, and a light source 116 invisible to the naked eye. Power to activate all electro-optical and electronic elements of imager 102 is preferably supplied from the tank's power plant through a physical connection, or from batteries (not shown) attached to the imager. The operation of the remote boresight, or the "remote boresighting" procedure of the present invention includes: a user, for example the gunner of the tank or armored vehicle inserts an internal boresight 10 into muzzle 12, or permanently attaches external boresight 10' to muzzle 12; the user then enters the tank, and views a target acquired through imager 102, a target which is displayed on a monitor inside the tank or armored vehicle. The user then sets the tank sight on the same target, so that a cross-hair on the sight is centered on the same point as the cross-hair on the monitor (which is either an image of a physical cross-hair of the telescope, or an electronically imposed cross hair). The gun muzzle axis and the tank sight are thus aligned, the procedure requiring only one user. At the end of the boresighting, the user exits the tank and removes internal boresight 10 from muzzle 12. If an external boresight is used, it normally remains permanently attached to gun 14. The same user preferably performs periodically the abovementioned alignment checks.

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims

Claims

WHAT IS CLAIMED IS:

1. A method by which a precise alignment of a gun relative to a sight is performed by a single user, comprising the steps of: i. attaching a boresight to the gun, said boresight including an electro-optic imaging device; ii. acquiring an image of said target through said boresight; iii. transmitting said image to a remote display positioned in proximity to the sight; iv. viewing said target through the sight; and v. aligning said image with said target viewed through the sight;

2. The method of claim 1, wherein said attaching includes inserting said boresight inside a muzzle of the gun.

3. The method of claim 1, wherein said attaching includes permanently attaching said boresight externally to the gun.

4. The method of claim 1, wherein said acquiring includes acquiring a video image.

5. The method of claim 3, wherein said attaching renders parallel a longitudinal axis of said boresight and a longitudinal axis of the gun.

6. The method of claim 1, wherein said transmitting is effected via a hardwired link between said imaging device and said display.

7. The method of claim 1, wherein said transmitting is effected via a wireless transmission.

8. The method of claim 4, wherein said aligning further includes superimposing a cross hair on said video image.

9. The method of claim 8, wherein said cross hair is provided electronically.

10. An apparatus for the precise alignment of a gun relative to a sight, the gun having a muzzle, comprising: a. a boresight operative to be secured to the gun, said boresight including an electro-optic imaging device for acquiring an image of a target; and b. a remote display for displaying said target.

11. The apparatus of claim 10, further comprising a mechanism for transmitting said image from said imaging device to said remote display.

12. The apparatus of claim 10, further comprising a mechanism for superposing a cross hair on said image.

13. The apparatus of claim 11, wherein said mechanism for transmitting includes a wireless mechanism.

14. The apparatus of claim 11, wherein said mechanism for transmitting includes a hardwired link.

15. The apparatus of claim 12, wherein said mechanism for superposing generates said cross hair electronically.

16. The apparatus of claim 10, wherein said boresight is operative to be reversibly secured to the gun.

17. The apparatus of claim 10, wherein said boresight is operative to be reversibly inserted in the muzzle.

18. The apparatus of claim 10, wherein said boresight is fixedly attached to the gun.