TECHNICAL FIELD
[0001] There are presented a method and an apparatus for aiming a target by a firearm.
BACKGROUND
[0002] Many firearms such as rifles are equipped with optical scopes to aid in accurate
positioning of the firearm's point of aim (POA). When shot, a bullet's point of impact
(POI) at a target varies depending on various ballistic parameters associated with
the bullet and the shooting environment. Some of the common ballistic parameters include,
for example, the bullet type, distance to the target, wind speed, etc.
[0003] In order to place the bullet where the rifle is aimed at, the POA needs to coincide
sufficiently close to the POI. If it is not, the POA needs to be "sighed in" such
that the POA is moved towards the POI. Typically, a shooter "zeroes" the POA such
that the POA coincides with the POI at a given distance. The shooter then relies on
a ballistic table or prior experience to estimate either a rise or drop of the bullet
at other varying distances.
[0004] There are known optical scopes for firearms with embedded ballistic computer and
integrated with a camera, a distance meter, a gyroscope, a hygrometer or a wind speed
meter. The gyroscope allows for precise leveling of the firearm, which has a big impact
on the trajectory of the bullet, as the ballistic tables assume that the firearm is
oriented such that the cross-sectional plane of the firearm is oriented in parallel
to the Earth's gravity vector. In case the firearm is tilted, the trajectory of the
bullet runs along another plane. For example, when the scope, which is attached to
the firearm's barrel is tilted 15
0 leftwards, the shooter who looks via the scope will have an impression that the bullet
is attracted downwards via a gravity force along the vertical line of the scope's
sight, while in fact the force of gravity affects the bullet an angle of 15
0 with respect to the sight's vertical line.
[0005] The data collected from the sensors are used to calculate the trajectory of the bullet.
This results in a set of output values such as the velocity, energy, angle of inclination
of the bullet with respect to the tangent of the path of travel of the bullet in a
plurality of points. The shooter may be presented with, for example on the screen
of the sight, coordinates of the point which should be aimed at (POA) to hit the target
point (POI). Using the scale of the scope, the shooter may displace the firearm vertically
or horizontally by computer-provided correction coordinates.
[0006] There are known in the art various methods and devices which facilitate aiming and
optical sighting of a firearm.
[0007] A US patent application
US20080163536 discloses a sighting mechanism for a firearm, including a video camera, a video screen,
a digital sighting distance meter, at least one sensor for measuring environment,
cartridge and/or weapon parameters, at least one biometric sensor, at least one memory
module for biometric data and/or munitions data and a digital computer. The sighting
device includes at least two video cameras arranged in a parallel manner in relation
to each other to capture the target sighting field. The computer has at least two
video input points and an image processing unit enabling the video image data to be
superimposed in real time in a pixel precise manner in relation to the target field
and to be reproduced on the screen.
[0008] A US patent
US8453368 discloses an electromechanical system that translates an "aiming error" signal from
a target tracking system into dynamic "pointing corrections" for handheld devices
to reduce pointing errors due to man-machine wobble without specific direction by
the user. The active stabilization targeting correction system works by separating
the "support" features of the handheld device from the "projectile launching" features,
and controlling their respective motion by electromechanical mechanisms.
[0009] A US patent application
US20080098640 discloses telescopic gunsights and associated equipment used to achieve shooting
accuracy.
[0010] A European patent application
EP1817538 discloses an automatic optical sighting system that generates at least one adjustment
for an adjustable optical system based on at least one detected condition, an appropriate
dynamic model of a projectile in flight, and a solution of the equations of motion
in flight, so that the projectile will have a trajectory between an origin and a selected
target that helps the projectile to hit the target.
[0011] A
US patent US8468930 discloses a rifle scope system that allows adjustment of the point-of-aim of a scope
while a shooter maintains the shooting posture and the scope sight picture. The scope
system saves ballistic parameters and the associated point-of-aim information of a
shot in a database of empirical data points. While the scope is aimed at a target,
a processor may use the empirical data points along with the ballistic parameters
of the target to determine point-of-aim adjustments of the scope. The adjustment system
allows processor-determined adjustments to be effected in a quick manner.
[0012] A US patent
US7269920 discloses a device that can be supported on a weapon, and has a range portion that
specifies a range to a target, a sensor portion that provides sensor information representing
an orientation of the device; and a sight that facilitates weapon orientation in preparation
to fire the ammunition. The device has an electronic control portion responsive to
sensor information from the sensor portion and a range from the range portion for
calculating how to hit a target with an ammunition, and for causing the sight to present
a visual indication of how to orient the weapon so that the ammunition will hit the
target, the electronic control portion terminating the presentation of the visual
indication by the sight in response to a lack of user activity for a selected time
interval during the presentation of the visual indication.
[0013] The known firearm sighting devices allow to set the position the barrel of a firearm
along a vertical and horizontal line of the scale of the sight to take into account
the correction calculated by the ballistic computer. However, vertical orientation
of the firearm requires additional controlling based on the readings of a gyroscope
or a compass.
[0014] The known timing devices do not take into account the coordinates of the gravity
vector, which are taken into account in the ballistic calculations, which may impact
the shooting accuracy.
[0015] There is a need to provide a method and device for optical target aiming that would
allow to take into account the gravity vector while aiming.
SUMMARY
[0016] The object of the invention is an apparatus for aiming a target by an optical scope
mounted on a firearm, the apparatus comprising a ballistic computer, an acceleration
sensor and a target aiming system comprising means configured to generate pairs of
stimuli for indicating inaccuracies of positioning of the apparatus with respect to
the vector of gravity, wherein the same stimuli of the pair indicate a correct positioning
in a particular direction and different stimuli of the pair indicate a direction of
deviation from the correct positioning in a particular direction.
[0017] Preferably, the stimuli are lights of variable colors.
[0018] Preferably, the apparatus further comprises light emitting diodes for generating
the stimuli.
[0019] Preferably, the stimuli are generated at an overlay mounted between the scope and
the eye of the shooter.
[0020] Preferably, the stimuli are acoustic signals of variable volume, frequency and/or
direction.
[0021] Preferably, the apparatus further comprises earphones for generating the stimuli.
[0022] Preferably, a pair of stimuli is configured to indicate the inaccuracy of positioning
of the apparatus with respect to the vector of gravity in a horizontal plane.
[0023] Preferably, a pair of stimuli is configured to indicate the inaccuracy of positioning
of the apparatus with respect to the vector of gravity in a vertical plane.
[0024] Preferably, a pair of stimuli is configured to indicate the tilt of inaccuracy of
positioning of the apparatus with respect to the vector of gravity.
BRIEF DESCRIPTION OF FIGURES
[0025] The method and device have been presented by means of example embodiments on a drawing,
in which:
Fig. 1 shows a schematic of an aiming scope having embedded target aiming system;
Figs. 2A, 2B show schematically the scope with the target aiming system;
Figs. 3A, 3B show schematically an example of signaling the error of incorrect positioning
of the firearm in horizontal plane by means of the target aiming system;
Figs. 4A, 4B show schematically an example of signaling the error of incorrect positioning
of the firearm in vertical plane by means of the target aiming system;
Figs. 5A, 5B show schematically an example of signaling the error of incorrect positioning
of the firearm in sideward tilt by means of the target aiming system;
Figs. 6A, 6B show schematically an example of simultaneous signalization of all aiming
errors by means of the target aiming system.
DESCRIPTION OF EMBODIMENTS
[0026] Fig. 1 presents a device 100 for optical sighting of a firearm. The device has a
form of an optical scope 100 which can be used for firing at small, medium and large
distances. The scope 100 comprises a ballistic computer 110, an acceleration sensor
120 for reading the position of the scope 100 with respect to the gravity vector,
an input interface 150 (such as a touch screen, on which a keyboard can be displayed),
a ballistic database 130 and a display 170 (e.g. a LED, OLED or e-ink display, preferably
with low energy consumption parameters). The display 170 presents various information
regarding the firearm, the ammunition, environmental data (such as the temperature,
atmospheric pressure, humidity) or ballistic correction calculated by the ballistic
computer 110. The scope 100 further comprises a target aiming system 160 for signaling
the corrections of orientation of the firearm with respect to the vector of gravity
and to provide the shooter with acoustic and/or visual stimuli.
[0027] The target aiming system 160 is connected to the ballistic computer 110 and signals
inappropriate orientation of the firearm. The scope may further comprise additional
environmental sensors 140, such as a thermometer, a distance meter, a hygrometer,
a barometer or a wind speed sensor, the outputs of which are input to the ballistic
computer 110.
[0028] Fig. 2A shows schematically the scope 100 with the target aiming system 160. The
scope 100 is mounted to the barrel 101 of the firearm, wherein the longitudinal axis
of the barrel and the longitudinal axis of the scope are fixed at a known angle. The
angle may be fixed such as for a given distance (e.g. 100m) a given bullet hits a
point aimed by the centre of the scope cross.
[0029] Fig. 2B shows the scope in a view from the shooter's side, looking at the sight.
[0030] In one embodiment, the target aiming system is a visual system, preferably comprising
light emitting diodes (LEDs) 161. The color of diode light may inform the shooter
of whether the firearm is oriented appropriately with respect to the Earth gravity
vector or not. The LEDs may be positioned behind the sight of the scope or embedded
in an overlay 162, preferably in form of a ring, to be attached to the scope 100.
The shooter, looking at the sight, may then see the diodes 161 that are positioned
at the periphery of the sight's round area. The target aiming system 160 may preferably
comprise three pairs of LEDs: 161A, 161 B, 161C. Each diode 161 may light with at
least two colors, for example green and red, wherein one color signals incorrect positioning
of the firearm and the other color signals correct positioning of the firearm. Each
pair of diodes 161 A, 161 B, 161C may operate independently of the other pairs. The
first pair 161A (positioned for example along the horizontal scale line) 'may indicate
firearm positioning errors in the horizontal plane. The second pair 161 B (positioned
for example along the vertical scale line) may indicate firearm positioning errors
in the vertical plane. The third paid 161C (positioned for example at the top half
of the sight, between the other diodes, each diode being in a different quarter of
the sight) may indicate firearm deviations sideward with respect to the gravity vector.
[0031] Figs. 3A, 3B show schematically an example of signaling the error of incorrect positioning
of the firearm in horizontal plane, i.e. perpendicular to the gravity vector (g) by
means of the target aiming system diodes 161A. In case the firearm is inappropriately
positioned in the horizontal plane, the diodes of the pair 161A emit different colors
of light. One color (e.g. red, orange or yellow) indicates the incorrect direction
and the other color (e.g. green, blue or white) indicates the direction in which the
position should be corrected. Fig. 3A presents an example of an error in the horizontal
plane, which needs to be corrected by moving the firearm towards the right side (i.e.
from the red diode towards the green diode). Fig. 3B presents an example of an error
in the horizontal plane, which needs to be corrected by moving the firearm towards
the left side (i.e. from the red diode towards the green diode). The amount of the
movement can be calculated on the basis of the readings of the environmental sensors
140, for example a sensor of wind speed and direction.
[0032] Figs. 4A, 4B show schematically an example of signaling the error of incorrect positioning
of the firearm in the vertical plane, i.e. parallel to the gravity vector (g) by means
of the target aiming system diodes 161 B. In case the scope is positioned too high
above the target (Fig. 4A), the top diode of the pair 161 B may light in red, while
the bottom diode may light in green. Alternatively, in case the scope is positioned
too low below the target (Fig. 4B), the top diode of the pair 161 B may light in green,
while the bottom diode may light in red. After the scope is oriented appropriately
in the vertical plane, both diodes glow with the same green color.
[0033] Figs. 5A, 5B show schematically an example of signaling the error of incorrect positioning
of the firearm in sideward tilt by means of the target aiming system. A firearm that
is positioned correctly shall have the plane, which comprises the longitudinal axis
of the firearm barrel and the longitudinal axis of the scope, parallel to the gravity
vector (g). Fig. 5A presents situation where the firearm is tilted towards the right
side and Fig. 5B presents the situation where the firearm is tilted towards the left
side.
[0034] Figs. 6A, 6B show schematically an example of simultaneous signalization of all aiming
errors by means of the target aiming system. In Fig. 6A, the bottom diode, the left
diode glow in red and both tilt indicating diodes 161C glow in green - this indicates
that the firearm shall be moved rightwards and upwards. After that position is corrected,
all diodes will glow green, as shown in Fig. 6B.
[0035] In another embodiment of the target aiming system 160, the inaccuracies in firearm
positioning may be signaled acoustically. For example, the shooter may be equipped
with stereophonic earphones coupled with the scope 100. An incorrect tilt may be signaled
by different tones in the left and right earphone - if the firearm is tilted leftwards,
the earphone may emit a low frequency sound in the left earphone and high frequency
sound in the right earphone. Correct tilt may be indicated by playing the tones of
the same frequency in both earphones if other errors exist or lack of sound if weapon
is aimed correctly. An incorrect positioning in the horizontal plane may be signaled
by a different volume of tones - the side towards which the firearm is incorrectly
directed may have a louder tone. Correct positioning in the horizontal plane may be
indicated by playing tones of the same volume in both earphones if other errors exist
or lack of sound if weapon is aimed correctly. An incorrect positioning in the vertical
plane may be signaled by varying the level of tones in both earphones - if the firearm
is directed too high, the tones of both earphones are of increased frequency, and
if the firearm is directed too low, the tones of both earphones are of decreased frequency.
Correct positioning in the vertical plane may be indicated by a medium frequency or
no sound at all. The signals may be played cyclically to indicate different errors
in different time slots, or may be combined. In case of combined signals, when the
earphones emit a generally high frequency signal, which is louder in the left earphone,
this indicates that the barrel is directed too high and too much towards the left
side.
[0036] The target can be indicated by moving the center of the sight of the scope to point
at the target and indicating the target by e.g. pressing a dedicated button on the
input interface 150.
[0037] The aiming is defined as correct if it is within the allowable accuracy range (dead
zone), which may depend on the target distance. For example, at a 50m target distance
the allowable inaccuracy may be defined as 1cm (measured on the target surface) of
horizontal/vertical deviation and 1
0 of tilt of firearm-scope arrangement with respect to the gravity vector. The values
of allowable errors can be entered to the computer manually by the user, which allows
to adjust the device to the skills of the shooter. For example, a less experienced
shooter may select higher values of allowable errors.
[0038] The presented method and system do not require a dedicated optical scope. The shooter
looks only at the sight of the scope, without the need to look at other devices, such
as a gyroscope or a compass, therefore the shooter's attention is not distracted away
from the scope.
[0039] Use of the acceleration sensors allows to use the gravity data for ballistic calculations:
not only for calculating the angle of inclination of the barrel, but also for calculating
the tilt error of the firearm-scope arrangement. Therefore, the presented device may
signal the tilt error with respect to the gravity error, which was realized in the
prior art using gyroscopes, which did not allow achieving accurate aiming. The gyroscopes
used in the prior art devices are characterized by a large thermal and temporal drift,
wherein these drifts are smaller for acceleration sensors (and can be easily corrected).
[0040] In order to compensate the thermal and temporal drift error, the acceleration sensor
should be calibrated by positioning the firearm in a horizontal position, such that
the plane defined by the longitudinal axis of the barrel and the longitudinal axis
of the scope is vertical. For such position, the computer of the scope shall be calibrated
(by pressing dedicated key). By inputting such data, the thermal and temporal drift
errors of acceleration sensor can be zeroed.
[0041] The presented aiming system allows to signal the direction of the correction of barrel
direction without giving precise information on how much the barrel should be displaced.
The system only presents the direction of the correction and signals when the firearm
is positioned correctly. While the shooter corrects the position, the ballistic computer
recalculates the parameters of the bullet trajectory. When the calculated point of
impact is sufficiently close to the target, the system signals to the shooter a correct
position.
[0042] The presented system can be used by inexperienced user, to allow them to quickly
aim at the target. Moreover, as the device uses low power consuming components, it
can be used in field conditions where battery replacement is problematic. When the
battery is discharged or when the target aiming system becomes damaged for any reason,
the scope can be still used in a typical manner.
1. An apparatus for aiming a target by an optical scope (100) mounted on a firearm, the
apparatus comprising a ballistic computer (110), an acceleration sensor (120) and
a target aiming system (160) comprising means (161A, 161 B, 161C) configured to generate
pairs of stimuli for indicating inaccuracies of positioning of the apparatus with
respect to the vector of gravity, wherein the same stimuli of the pair indicate a
correct positioning in a particular direction and different stimuli of the pair indicate
a direction of deviation from the correct positioning in a particular direction.
2. The apparatus according to claim 1, wherein the stimuli are lights of variable colors.
3. The apparatus according to claim 2, comprising light emitting diodes (161) for generating
the stimuli.
4. The apparatus according to claim 2 or 3, wherein the stimuli are generated at an overlay
(162) mounted between the scope (100) and the eye of the shooter.
5. The apparatus according to claim 1, wherein the stimuli are acoustic signals of variable
volume, frequency and/or direction.
6. The apparatus according to claim 5, comprising earphones for generating the stimuli.
7. The apparatus according to any of the preceding claims, wherein a pair of stimuli
(161A) is configured to indicate the inaccuracy of positioning of the apparatus with
respect to the vector of gravity in a horizontal plane.
8. The apparatus according to any of the preceding claims, wherein a pair of stimuli
(161 B) is configured to indicate the inaccuracy of positioning of the apparatus with
respect to the vector of gravity in a vertical plane.
9. The apparatus according to any of the preceding claims, wherein a pair of stimuli
(161 C) is configured to indicate the tilt of inaccuracy of positioning of the apparatus
with respect to the vector of gravity.
Amended claims in accordance with Rule 137(2) EPC.
1. An apparatus for aiming a target by an optical scope (100) mounted on a firearm, the
apparatus comprising a ballistic computer (110), an acceleration sensor (120) and
a target aiming system (160) comprising means (161A, 161B, 161C) configured to generate
pairs of stimuli for indicating inaccuracies of positioning of the apparatus
the apparatus being
characterized in that
• the inaccuracies of positioning are with respect to the vector of gravity;
• wherein an accurate positioning is such that plane comprising the longitudinal axis
of the firearm barrel and the longitudinal axis of the optical scope (100) is parallel
to the vector of gravity; and
• wherein the same stimuli of the pair indicate a correct positioning in a particular
direction and different stimuli of the pair indicate a direction of deviation from
the correct positioning in a particular direction; and
• whereas the aiming is determined as correct if the inaccuracies are within an allowable
accuracy range, which depends on the target distance.
2. The apparatus according to claim 1, wherein the stimuli are lights of variable colors.
3. The apparatus according to claim 2, comprising light emitting diodes (161) for generating
the stimuli.
4. The apparatus according to claim 2 or 3, wherein the stimuli are generated at an overlay
(162) mounted between the scope (100) and the eye of the shooter.
5. The apparatus according to claim 1, wherein the stimuli are acoustic signals of variable
volume, frequency and/or direction.
6. The apparatus according to claim 5, comprising earphones for generating the stimuli.
7. The apparatus according to any of the preceding claims, wherein a pair of stimuli
(161A) is configured to indicate the inaccuracy of positioning of the apparatus with
respect to the vector of gravity in a horizontal plane.
8. The apparatus according to any of the preceding claims, wherein a pair of stimuli
(161B) is configured to indicate the inaccuracy of positioning of the apparatus with
respect to the vector of gravity in a vertical plane.
9. The apparatus according to any of the preceding claims, wherein a pair of stimuli
(161C) is configured to indicate the tilt of inaccuracy of positioning of the apparatus
with respect to the vector of gravity.