阅读说明：本技术 用于检测射击事件的设备和方法 (Device and method for detecting a firing event ) 是由 戴夫·巴雷特 李文 卡特·克里滕登·本内特 斯科特·比林顿 史蒂文·弗雷德·赫林 于 2019-03-18 设计创作，主要内容包括：一种通过连续脉冲与枪支或模拟枪支的枪管同轴对准的激光来确定枪支或模拟枪支在射击时的瞄准点的方法。然后,通过观察目标的摄像机系统连续检测瞄准点。检测到射击事件,并确定射击事件之前在目标上最后检测到的激光脉冲位置。从最后检测到的激光脉冲位置以及在最后一个激光脉冲位置之前的至少一个激光脉冲位置外推枪支或模拟枪支在射击时的瞄准点。(A method of determining the aiming point of a firearm or simulated firearm when fired by continuously pulsing a laser coaxially aligned with the barrel of the firearm or simulated firearm. The aiming point is then continuously detected by the camera system observing the target. A firing event is detected and the last detected laser pulse position on the target prior to the firing event is determined. Extrapolating the aiming point of the firearm or simulated firearm at the time of the fire from the last detected laser pulse position and at least one laser pulse position prior to the last laser pulse position.)

1. A method of determining an aiming point of a firearm or simulated firearm when fired, comprising:

continuously pulsing a laser at a frequency greater than 1Hz, wherein the laser is mounted on and coaxially aligned with a barrel of a firearm or simulated firearm;

continuously detecting laser pulse positions from the laser on the target;

detecting a firing event with a sensor mounted on a firearm or simulated firearm;

determining a last detected laser pulse position on the target prior to the firing event;

extrapolating the aiming point of the firearm or simulated firearm at the time of the fire from the last detected laser pulse position and a plurality of laser pulse positions prior to the last laser pulse position.

2. The method of claim 1, further comprising including the step of extrapolating the location of the at least one laser pulse on the target after the firing event.

3. The method of claim 2, wherein the weight of at least one location after a firing event is reduced.

4. The method of claim 2, wherein a plurality of laser pulse positions on the target after the firing event are used.

5. The method of claim 1, wherein the sensor is an accelerometer.

6. The method of claim 1, wherein the sensor is an ultrasonic sensor.

7. The method of claim 1, wherein the frequency is greater than 10 Hz.

8. The method of claim 1, wherein the frequency is greater than 20 Hz.

9. The method of claim 1, wherein the frequency is divisible without remaining into a frame rate of a detection camera that continuously detects laser pulse positions from the laser on the target.

10. The method of claim 1, wherein the frequency and timing of the continuous pulse laser is adjusted so that the laser pulse position of the laser on the target will occur when the shutter of the detection camera is opened.

11. A method as claimed in claim 10 wherein each of the plurality of firearms or simulated firearms has a laser mounted thereon and aimed by the barrel of the firearm or simulated firearms and each laser pulses are emitted continuously in a repetitive sequence so that each laser pulse position of the laser light on the target occurs when the shutter of the detection camera is opened.

12. The method according to claim 10 or 11, wherein the frame rate of the detection camera is 60 Hz.

13. A method of determining an aiming point of a firearm or simulated firearm when fired, comprising:

pulsing a laser at a frequency of 10Hz or higher, wherein the laser is aimed by a barrel of a firearm or simulated firearm;

detecting a laser pulse position from the laser on the target;

detecting a firing event;

determining a last detected laser pulse position on the target prior to the firing event;

extrapolating the aiming point of the firearm or simulated firearm at the time of the fire from the last detected laser pulse position and at least one laser pulse position prior to the last laser pulse position.

14. The method of claim 13, wherein the detecting step is performed by at least one camera viewing the target.

15. The method of claim 13, further comprising including the step of extrapolating at least one laser pulse position after the firing event.

16. The method of claim 15, wherein the weight of the at least one location after the firing event is reduced.

17. The method of claim 13, wherein the detecting step is performed by a sensor coupled to a firearm or an analog firearm.

18. The method of claim 17, wherein the sensor is selected from the group consisting of an ultrasonic sensor and an accelerometer.

19. The method of claim 14, wherein the pulsed laser is synchronized with a shutter of a camera such that a laser pulse position occurs when the shutter is open.

20. The method of claim 13 wherein each of the plurality of firearms or simulated firearms has a laser aimed at by a barrel of the firearm or simulated firearms and each laser pulses in a repeating sequence such that each laser pulse position on the target occurs when a shutter of the detection camera is open and only one laser pulse occurs on the target at a time.

Technical Field

This patent document relates generally to weapons training and weapons training systems. More particularly, this patent document relates to apparatus and methods for detecting firing events for use in weapon simulation systems. Several approaches have been developed which all improve upon the prior art.

Background

In most weapon training systems that attempt to detect the aiming point, it is important to be able to detect the speed of the firing event because when the bullet starts to move, the weapon sits back and changes the aiming point. Thus, the faster a firing event is detected, the more accurately the aiming point can be detected.

In a typical firing event, the shooter pulls the trigger and releases the motor spring which pulls the spring-loaded firing pin. The time at which the unconstrained striker impacts the back of the cartridge case is referred to as the "lock time". The lock time is approximately 2-20 milliseconds depending on the design of the firearm, etc. Next, the powder in the cartridge case is ignited by igniting the primer in the cartridge case. For a pistol, the cartridge will exit the barrel in about 1 millisecond, for a rifle, the cartridge will exit the barrel in about 3 milliseconds. This is the time the bullet is accelerated and ejected in the barrel. For a handgun, the round may be accelerated to about 1100 feet/second, but the barrel is only about 6 inches long. For a rifle, the bullet may be accelerated to about 3000 feet per second, but the barrel may be 26 inches long. It is important that the bullet effectively leaves the gun once the primer is struck. The gas pushing the cartridge out of the barrel also creates a reaction force pushing it to the rear of the gun. This reaction is called recoil. At the instant of brief firing, the mass of the gun accelerates and begins to move as a function of recoil. This recoil or recoil is reacted by the human body within 10 milliseconds, depending on the shooter. At this point, the aiming point is greatly disturbed. However, the bullet leaves the barrel before any significant movement occurs. Essentially, the bullet will run to the place where the gun is aimed before shooting, because the recoil has little time to move the gun before the bullet leaves.

From a sensing perspective, the most common sensor used to measure firing events is an accelerometer. In current systems, the laser light mounted on the firearm and barrel sight is pulsed when the accelerometer senses a firing event. When recoil is generated from a live ammunition or even a simulated pneumatic system, the firearm must move above a preset acceleration threshold to detect the firing event and fire the laser pulse. By definition, a firearm must have moved to be certified. Thus, when the firearm is pointed at a different location than the actual firing position, the laser pulse is fired and recorded.

In the simulation system using the mechanical actuation system, no bullet was shot. All forces must be reacted internally. Thus, when the striker strikes the open pneumatic valve (which ultimately actuates the bolt), the commonly recorded impact position may be below the actual aiming point. When the top of the gun is pushed backwards, the front of the gun is pushed downwards.

Therefore, it would be advantageous to develop methods and systems that can more accurately detect the aim point of a shooter.

There are many kits on the market to retrofit real firearms for weapon training. These kits contain a variety of techniques that may allow the weapon training system to assess the use of a trainee's firearm. For example, these kits may include a laser mounted coaxially with the barrel of a firearm to allow the weapon system to determine the target and the strike point. These kits may include a system for simulating recoil. A system for simulating recoil is disclosed in U.S. patent No. 6,869,285 (hereinafter the "285 patent").

Many firearm simulator markets use a device known as a "Dvorak kit. The Dvorak kit may include a recoil simulator such as that disclosed in the' 285 patent. In order to record weapon movements for training purposes, most of the kits in use comprise an inertial measurement unit ("IMU").

It may be difficult to hide all the electronics needed to convert a weapon into a weapon that can be used for training purposes in a weapon simulator. Moreover, in many cases it is desirable that the weapon be, in most cases, a firearm, most of which remains unmodified. To this end, it is desirable to construct a device that can be used to retrofit weapons (particularly firearms) with minimal modification, while still providing as much data as possible to the weapon training system. With such a system, real-time weapons can be used in weapon simulators and weapon owners trained.

With regard to weapon training and weapon simulators, one of the most important data points to obtain is the firing event. Accurate detection of the firing event can accurately measure the aiming point of the trainee in time and calculate the hit point. This can be difficult as the gun aiming point is moving at all times. It may also allow the system to detect movement of the firearm before, during, and after shooting. These data can be analyzed and used to provide valuable feedback to the shooter regarding shooting errors and/or corrective measures, many of which occur before, during, or after the shooting event.

There are many firing event detection devices on the market. Several solutions surround a laser shooter and an electronic trigger that is packaged as an insert that fits into the bore or barrel of a firearm. These products use a switching mechanism or similar hardware to sense the pulse delivered by the firing pin, applied by the hammer or active firing pin (depending on the configuration of the firearm). After the pulse is delivered, the firing pin is the only moving part in the firearm. These systems are very accurate in detecting firing events. In some cases, the switching mechanism is mounted on a valve (valve). The effect on the switching mechanism is further transferred to the pneumatic valve which actuates the simulated recoil.

Other systems for detecting trigger pulls are rail mounted devices that do not contact the moving internal components. These devices may also pulse the laser, but require the use of inertial sensors in the rail mounted device to record the firing event. The movement of the entire firearm due to recoil is used to demonstrate that the firearm has fired. Since the system is waiting for recoil to detect the shot, the system cannot accurately detect the aiming point because the aiming point has been greatly disturbed by recoil. By the time the laser pulses are fired and measured by the camera system, the weapon has substantially moved from the true aiming point. The resulting inaccuracies are a common practice accepted in the industry.

To this end, it would be beneficial to provide a method that can more accurately detect the occurrence of a firing event with minimal modification to existing weapons. It would also be beneficial to provide a method of detecting firing events that is suitable for existing weapon systems and existing weapon simulation systems, including recoil systems and the like.

Disclosure of Invention

It is an object of the present patent document to provide an improved method of detecting firing events of a firearm or weapon during weapon training. It is a further object of this patent document to provide a method and apparatus for detecting a firing event that eliminates or at least ameliorates some of the problems known in the art. To this end, a method of determining an aiming point of a firearm or simulated firearm at the time of firing is provided.

In some preferred methods, the laser aimed at the barrel of the firearm or simulated firearm is continuously pulsed. The laser is preferably pulsed at a frequency of 1Hz or higher. In a more preferred embodiment, the laser is pulsed at a frequency of 10Hz or 20Hz or higher. In other embodiments, the laser may be pulsed even faster, such as 50Hz, 100Hz, or even faster. In most embodiments, the laser is mounted to a firearm or simulated firearm because it is difficult to aim the laser in any other way.

The laser pulse position from the pulsed laser is continuously detected on the target. In a preferred embodiment, this is achieved by one or more cameras designed to detect the pulses.

A firing event is detected. The firing event may be detected by a sensor mounted on the firearm or a simulated firearm. The sensor may be any type of sensor capable of detecting a firing event. For example, an accelerometer or an ultrasonic sensor as taught herein may be used.

Upon detection of a firing event, an aiming point of the firearm or simulated firearm at the time of firing is inferred from the last detected laser pulse position and at least one other laser pulse position prior to the last laser pulse position. In a preferred embodiment, a number of points before the last laser pulse position before firing are used to infer the aiming point at the time of firing.

In some embodiments, at least one laser pulse position on the target after the firing event may also be used to determine the aim point at the time of the shot. In some embodiments, multiple laser pulse positions on the target after the firing event are used to determine the aiming point. In most embodiments, the factors in determining the position of a laser pulse in a target from after a firing event are less weighted or important than the position before the firing event.

In a preferred embodiment, the system is designed for use in a training facility that uses multiple firearms at a time. In such embodiments, each weapon may have a laser mounted thereon, and all lasers may be sequentially pulsed such that only one laser is impinged on the target at a time. Preferably, the pulsed laser is synchronized with the shutter of the camera so that when the shutter of the camera is detected to be open, the pulses from the laser illuminate the target. For this reason, the frequency of the laser pulses is preferably divisible without remaining in the frame rate of the detection camera that continuously detects the laser pulse position from the laser light on the target. Thus, the faster the frame rate of the camera, the faster the laser pulses can be generated. In a preferred embodiment, the frame rate of the camera is 60 Hz.

In some embodiments, the device for detecting a triggering pull event is an ultrasonic sensor. In such embodiments, a device for detecting a firearm firing event using an ultrasonic sensor is provided. In a preferred embodiment, the apparatus comprises: a housing comprising a rail interface on an exterior of the housing, wherein the rail interface is designed to attach to a rail of a firearm; a laser shooter mounted inside the housing; an IMU mounted within the housing; an ultrasonic sensor located inside the housing and in direct contact with an inner wall of the housing; and the microcontroller is electrically connected with the ultrasonic sensor.

Although any type of firearm or weapon may be used in conjunction with the disclosed apparatus and method, the system is typically used with a pistol or rifle.

Preferably, the ultrasonic sensor is an ultrasonic microphone, but any type of ultrasonic sensor may be used. The ultrasonic sensor may listen to or be sensitive to any frequency above 20kHz (human hearing limit) or in the vicinity thereof. However, in a preferred embodiment, the ultrasonic sensor listens to or is sensitive to frequencies greater than or equal to 40 kHz.

In some embodiments, the device may further comprise an acoustic wave generator located in the firing chamber of the firearm. In order to make it easier for the ultrasonic sensor to distinguish between the blows of the hammers, the sound generator emits an ultrasonic signal when struck by the hammers of the firearm. The ultrasonic sensor easily distinguishes the ultrasonic signal from the sound generator from other noise in the frequency band.

In another aspect of embodiments of the present patent document, a method of determining a weapon aim point at the time of firing is provided. In a preferred embodiment, the method comprises: mounting an electronic module on a rail or other mounting component of a weapon, wherein the electronic module comprises an ultrasonic sensor, an IMU, and a laser shooter; continuously pulsing a laser beam from a laser; monitoring the impact of the hammer by using an ultrasonic sensor; the time of delivery of the impact of the hammer; the aiming point of the weapon is calculated by combining the time of fire with the position information of the laser beam.

In systems using a continuous pulsed laser beam, the simulation system always records the weapon's pointing position. In this case, the speed of the detection of the firing event is less important. When a firing event is recorded, the simulation system looks back in time over the history of recorded muzzle positions to select the aiming point corresponding to the recorded delayed firing event.

In systems that do not have a continuously pulsed laser and do not continuously record muzzle position, a fast firing event sensor that can rapidly react laser pulses is critical.

In some embodiments, the method further comprises sending position information from the IMU in the calculating step and using the position information.

In some embodiments, the method may further comprise transmitting the ultrasonic signature from a sound generator, wherein the sound generator transmits when struck by a hammer of the firearm; and detecting the electronic signature from the acoustic generator with an ultrasonic sensor. In some embodiments, the method continuously records firing events from IMUs/accelerometers located in a rail mounted device. In some systems, successive bases (continuous bases) may repeat intervals. In a system using this method, the aiming point is determined by reviewing its recorded history over a specified time interval. In some embodiments, the firing event recording method in the device may be used to detect firing events of live ammunition or other combustion-based cartridge cases.

The above description is merely a summary of some possible embodiments and may be understood in more detail from the following detailed description, which is accompanied by reference to the accompanying drawings.

Drawings

Fig. 1 illustrates a method of detecting the aiming point of a firearm or weapon simulator by continuously pulsing the aiming laser.

Fig. 2 shows a firearm with a weapon simulator module attached to the firearm rail.

Fig. 3 illustrates a weapon simulator module mounted on a weapon rail.

FIG. 4 shows an internal view of a weapon simulator module.

Detailed Description

Depending on the camera, it may still take a long time to try to detect the aiming point of the weapon by means of a pulsed laser only after the camera system has detected a firing event. One possibility is to use a high frame rate camera (e.g. 300Hz) to detect the laser pulses. This means that shots can be recorded with a resolution of 3 milliseconds. In combination with a rapid ultrasound system to detect a firing event, the muzzle does not move much and the system is fairly accurate. In a rifle, it is even possible to record laser pulses at the same time as the bullet leaves the muzzle. However, it is desirable to use a camera that is slower and less expensive.

Fig. 1 illustrates a method of detecting the aiming point of a firearm or weapon simulator by continuously pulsing a laser coaxial with a bore. Unlike previous systems, which pulse the laser only after even a firing event is detected, the method and system of the present application continuously pulse the laser. The laser is preferably pulsed at a frequency of 1Hz or higher. In a more preferred embodiment, the laser is pulsed at a frequency of 10Hz or 20Hz or higher. In other embodiments, the laser may be pulsed even faster, such as 50Hz, 100Hz, or faster.

While in the preferred embodiment the laser is actually contained within, and thus coaxially aligned with, the bore of the barrel, in other embodiments the laser may be mounted to the firearm and aligned with the aiming location of the bore a distance from the firearm (e.g., with an aiming hole). The typical mounting location for the laser is usually at the top or bottom of the barrel, and in many embodiments the laser may be attached to rails at the top or bottom of the barrel.

As seen in fig. 1, the laser pulse position from each pulse of the pulsed laser is detected continuously on the target. Indicated in fig. 1 by the dots labeled 2, 3, 5 and 6. Each point represents a measurement of the aiming point or muzzle position of the firearm recorded at a particular time. In a preferred embodiment, the detection of the laser pulses on the target is effected by means of one or more cameras designed to detect the pulses. However, a light sensor or any other type of sensor may be used to detect the laser pulses incident on the target. The camera may be an array, a CCD camera or any other type of camera.

A firing event is detected. The firing event may be detected by a sensor mounted on the firearm or a simulated firearm. The sensor may be any type of sensor capable of detecting a firing event. For example, an accelerometer or an ultrasonic sensor as taught herein may be used. As can be seen from the difference between position 3 and position 5 in fig. 1, a large jump is detected after the shot. Typically, the shooter becomes stationary before the target is fired. With recoil, the position to which the muzzle is pointed changes very rapidly. However, as long as the accelerometer measured shot is recorded with a constant delay, the muzzle position at the time of trigger pull can be inferred from the previous movement of the firearm.

Once a firing event is detected, the aiming point 4 of the firearm or simulated firearm at the time of firing is inferred based on the last detected laser pulse position 3 and at least one other laser pulse position 2 preceding the last laser pulse position 3. In a preferred embodiment, a plurality of points 2 before the last laser pulse position 3 before the shot are used to extrapolate the aiming point 4 at the time of the shot.

The extrapolation method uses the shot time recorded from the motion sensor (or ultrasound sensor) to scale the extrapolated distance of the last recorded sighting position before shooting. Many different interpolation/extrapolation methods may be used, including linear extrapolation, polynomial or other methods, to name a few.

In a preferred embodiment, the time of the firing event is detected and time stamped. If the detection mechanism is on the firearm, the time of the firing event and the fact that it occurred may be transmitted to an external computer. This may be done by a wired or wireless link, but preferably by a wireless link and preferably by a radio frequency "RF" link.

The position of the gun's aiming point is recorded simultaneously with or before and after the firing event. Typically, this is done by a global shutter camera picking up the position of the pulsed laser on the firearm. The frame rate may be any frame rate, but a 60Hz shutter with fixed intervals may be used. Clearly, faster shutter speeds are more accurate, but cameras with faster shutter speeds are more expensive. The method described herein allows for more accurate calculation of the aiming point, more preferably below 60Hz, while still using a camera with a shutter speed below 120 Hz; and even more preferably below 30 Hz.

Returning to fig. 1, the camera records the X and Y positions of each laser pulse, as well as the time stamp for each position, to form a set (t, X, Y) of each laser pulse position. As shown in fig. 1, one set (t, x, y) may be recorded for each laser pulse 2A, 2B, 2C, 3, 5, and 6. Once the time of the firing event and the recorded laser pulse position are moved as the same frame of reference, they are compared to the "t" in each set of points to determine the last recorded position before the firing event. In the embodiment of fig. 1, position 3.

Once the timing of the firing event is established relative to the recorded positions of the laser pulses, a number of laser pulse positions prior to the firing event are determined for extrapolation of the actual aiming point at the time of firing. Any number of laser pulse positions may be used depending on the embodiment. In some embodiments, 10 laser pulse positions are used. In other embodiments, 8, 5, or even 3 laser pulse positions may be used.

Once the laser pulse point to be used for extrapolation is identified, all "x" components are used to extrapolate the x-position of the aiming point at the time of firing 4. All "y" components are then used to extrapolate the y-position of the aiming point at the shot 4. Extrapolating to "t" of the recorded firing event using the "x" and "y" positions.

If the time stamp of the firing event is not in the same global time as the camera frame, both need to be placed in the same time frame. The time stamp is either converted to a camera time frame or vice versa or both are converted to a third time frame, e.g. a global time.

In some embodiments, the "t" of the aiming point may be the timestamp of the actual recording of the firing event converted to the common reference frame at firing event 4, if desired. However, in some embodiments, a small delay may be subtracted from the actual "t" recorded as a firing event. The smaller delay is subtracted because most systems will have some type of delay in recording such events, and by subtracting a small amount of time from the actual time of recording, a more accurate aiming point can be calculated.

In some embodiments, the laser pulse position may be ignored even before the firing event if the time "t" of the laser pulse position is very close to the time of the firing event.

In some embodiments, after the firing event, at least one laser pulse position 5 on the target may also be used to determine the aiming point 4 at the time of firing. Although the post-shot positions are weighted very lightly in the calculation, it may be beneficial to interpolate the laser pulse position 5 after the shot event. In some embodiments, after a firing event, multiple laser pulse positions on the target are used to determine the aiming point. In most embodiments, the location after the firing event is given less weight or importance than the location before the firing event, taking into account the laser pulse location on the target after the firing event.

Since measurements need to be taken after the shot time, some pipeline delay may be added when sending the actual shot location into the simulation system. For example, even if a frame 50 of video is being displayed to a shooter, the system needs to use frame 49 to determine a hit or miss. Most analog systems play movies/graphics at 30 frames/second. In fact, as long as the computation of a hit or miss occurs in the appropriate frame, the user does not perceive the added 1 or 2 frame delay and does not affect the training quality.

The accuracy of such extrapolation may be difficult to measure when matching an accurate muzzle position. However, in the tests of live ammunition and simulated recoil systems, the trace extrapolation mechanism showed an improvement of several inches in accuracy at 5 meters shot distance. Depending on the exact use case, this can greatly affect the ability to train: the less accurate the system, the closer the target must be, and less emphasis is placed on gunning.

In a preferred embodiment, the system is designed for use in a training facility that uses multiple firearms at a time. In such embodiments, each weapon may have a laser mounted thereon, and all lasers may be sequentially pulsed such that only one laser is impinged on the target at a time. It is desirable to be able to track multiple weapons fired on the same screen and distinguish which fire. One method is to continuously pulse the laser light to different weapons, causing each weapon to drop 1 laser pulse in 1 frame acquired by the camera.

Preferably, the pulsed laser is synchronized with the shutter of the camera so that when the shutter of the camera is detected to be open, the pulses from the laser illuminate the target. For this reason, the frequency of the laser pulses is preferably divisible without remaining in the frame rate of the detection camera that continuously detects the laser pulse position from the laser on the target. Thus, the faster the frame rate of the camera, the faster the laser pulses can be generated. In a preferred embodiment, the frame rate of the camera is 60 Hz.

It will be appreciated that for a system with a 60Hz camera and 10 weapons, a maximum muzzle position of 6Hz will be recorded. A system with only 2 weapons can record a 30Hz target position.

In the embodiment of fig. 1, a pistol with a targeting laser pulsed at 20Hz is used, generating one data point for the muzzle pointing position every 50 milliseconds. This type of resolution would be too small a temporal resolution if the laser was not continuously pulsed.

However, in the embodiments taught herein, when combined with a pulsed laser, it is sufficient to use a common inexpensive accelerometer to detect the firing event. The accelerometer can record the time of recoil very accurately. The time stamp places the recoil between two consecutive camera frames recorded by the laser pulse.

Ultrasonic triggered pull detection

In live action weapons, the recoil force always lifts the muzzle upward due to the actual recoil force created by the bullet mass leaving the firearm. Unlike the continuous pulse laser systems described above, systems that rely on movement of the firearm to trigger the laser (whether live ammunition or simulation) will always have considerable inherent error.

When the sound propagates within the polymer/metal frame of the pistol, the speed of the sound is much higher than air, and the ultrasonic sensor can sense the explosion of the gunpowder or the drop of the blow of the hammer. This provides the advantage of recording firing events within 10 milliseconds compared to inertial sensors.

To install the weapon simulator system without modifying the weapon, and to detect firing events, this patent document discloses a rail mounted module that uses ultrasound to detect firing events from within the rail mounted module.

Fig. 1 shows a firearm 12, the firearm 12 having a weapon simulator module 20 attached to a rail of the firearm 12. Firearm 12 and weapon simulator module 20 constitute weapon simulator subsystem 10. The firearm 12 has a trigger 16. Although a firearm is shown in fig. 1, subsystem 10 may be constructed using any firearm. Such as crossbows, rifles, compound bows, pistols, bullet guns, machine guns, or any other type of weapon may be substituted for firearm 12. In particular, the weapon simulator module 20 is designed for use with a weapon that includes the trigger 16. This is because weapon simulator module 20 is specifically designed to detect firing events.

Fig. 2 shows the weapon simulator module 20 mounted on the weapon rail 14. It can be seen that the weapon simulator module 20 includes a weapon rail interface 21 that interfaces and engages with the weapon simulator module 20 and removably connects to the rail 14. It is well known in the art that an orbital interface system or RIS (also known as an orbital attachment system or RAS) can be used to secure an attachment to a weapon. Common accessories include tactical lights, laser aiming modules, forward grips, telescopic sights and even bayonet. To simplify the design of such accessories, there are many standardized RISs, including, for example, the Weaver rail mount, Picatinny rail (MIL-STD-1913), NATO accessory rail, Keymod, and M-LOK, among others. The interface 21 may use any of these standard RIS interfaces or may use a proprietary interface.

Fig. 3 shows an internal view of weapon simulator module 20. As can be seen, the embodiment of fig. 3 includes an ultrasonic sensor 23, an Inertial Measurement Unit (IMU)26, a microcontroller 24 and a laser 25, all mounted in a housing 22. The housing includes a rail interface 21 (shown in phantom). The housing may be made of any material, such as plastic, metal or ceramic. However, the housing is preferably made of metal, such as steel, aluminum or titanium or some mixture thereof, and even more preferably the housing is made of stainless steel.

In operation, the microcontroller is the brain of the weapon simulator module 20, receiving inputs from the ultrasonic sensor and IMU and commanding the laser. Weapon simulator module 20 optionally includes a wireless communication chip 27 that supports Bluetooth, IEEE802.11, or other wireless protocols to allow weapon simulator module 20 to communicate with other devices or systems.

In some systems, weapon simulator module 20 optionally includes one or more cameras. One or more cameras may be aware of the target at which the firearm is aimed at from a first-person perspective, and such video facilitates diagnosis and training.

The weapon simulator module 20 may also include a battery 28 or a battery pack 28 comprised of a plurality of batteries as is known in the art. The exterior of the housing 22 optionally includes a charging port 29, such as a USB charging port, to allow the unit 20, and in particular the battery 28, to be charged.

The ultrasonic sensor 23 is a key aspect of the present invention. Ultrasonic sensors (typically ultrasonic microphones) are designed to monitor and detect firing events. In a pistol, when the trigger is pulled, it activates the hammer. Firearms have Single Action (SA) and Double Action (DA) designs. In a single action firearm, the hammer must be cocked by hand and the trigger simply releases the hammer. In a double action design, the trigger can either move the hammer or release the hammer. Regardless of the design, firearms use a trigger to trigger the firing of a bullet in the firing chamber of the firearm. This is achieved by the combination of a spring and kinetic energy to drive the striking device, which kinetic energy is operated by the firing pin to strike and ignite the primer. The striking mechanism is mainly of two types: a hammer and an active firing pin. The hammer is a spring-tensioned metal block that, when released, pivots on a pin and strikes a firing pin to eject the cartridge case. The active firing pin is essentially a spring loaded firing pin that travels along an axis in line with the cartridge case, thereby eliminating the need for a separate hammer. In both cases, the hammer and the firing pin or the firing pin and the cartridge case collide. This collision creates an acoustic signature. The acoustic sensor 23 is designed to detect this acoustic feature.

Although extensive research has been conducted on the acoustic characteristics of firearms, the research has focused on muzzle blasts and shockwaves of supersonic bullets. Embodiments herein seek to detect an even earlier order, i.e. the order of the hammer and the firing pin. The ultrasonic sensor 23 is monitoring ultrasonic frequencies, typically greater than or equal to 40 KHz. The ultrasonic threshold and frequency band may be adjusted to sense the impact of the hammer in a cavity or live ammunition. Ultrasonic/acoustic emission may be superior to inertial sensors in its ability to distinguish events such as the end of action or a live fire.

As shown in fig. 3, the ultrasonic sensor 23 is installed in direct contact with the housing 22. In such embodiments, the ultrasonic sensor 23 may be pressed into contact with the housing 22. The housing is then mounted to the firearm via the rail interface 21 and thus in contact with the firearm itself. This brings the ultrasonic sensor into vibrationally sensed contact with the exterior of the firearm. Placing the ultrasonic sensor in direct contact with the housing 22 of the weapon simulator module 20 may increase the sensitivity or signal-to-noise ratio of the system and allow the ultrasonic sensor to more easily detect trigger pull.

In operation, the ultrasonic sensor 23 provides a signal to the microcontroller 24, and it is in effect the microcontroller 24 that determines whether the signal from the ultrasonic sensor 23 is in fact a trigger pull. Once it is determined that a trigger pull has occurred, microcontroller 24 may indicate that a signal that a trigger pull has occurred is to be sent to the simulator system. As part of this notification, the weapon simulator module 20 may also send information from the IMU26 regarding the orientation and location.

The weapon simulator system may then use information from the weapon simulator module 20 to determine the position, orientation and aiming point of the firearm when the trigger is pulled. In a preferred embodiment, the position and orientation of the firearm may be continuously buffered so that timely information prior to triggering a pull may also be retrieved and analyzed. In some embodiments, the weapon simulator system may also determine the location and aim of the weapon based on the location of the laser beam emitted from weapon simulator module 20. Weapon simulator module 20 may be mounted such that laser transmitter 25 is coaxially aligned with the barrel. The IMU26 may be used to correct parallel errors from tilt. The emitted laser light may be detected and triangulated to determine the location and aiming point of the weapon. In a preferred embodiment, the laser 25 is continuously pulsed from the weapon simulator module 20 so that the weapon simulator system can continuously track the position and aim point of the weapon.

In case it is difficult to distinguish the ultrasonic waves from the blows of the hammer, a battery powered or piezoelectric ultrasonic generator with a switching mechanism may be placed in the chamber. In this case, when the hammer strikes, a loud sound will be triggered to emit a uniquely tuned resonant ultrasonic sound. The tone can be distinguished from other naturally occurring acoustic emissions. The tone will be transmitted through the body of the weapon and read by the ultrasonic microphone 23 located in the weapon simulator module 20.

Existing recoil designs disclose the use of a pilot metering valve for a mechanically actuated recoil system. While the current weapon simulator module 20 may be used in conjunction with existing recoil systems, a motorized recoil system installed in the weapon may also be used. The device may require replacement of the barrel in the pistol, orA part of a bolt holder in An (AR) type weapon. The recoil mechanism may also be ultrasonically controlled and include a battery and a microcontroller. The microcontroller may be configured to open the valve: 1.) under the command of the weapon simulator module 20, this module can issue itselfFor the recoil system to read; or 2.) listening and interpreting the hammer strike acoustic emission signal alone.

In addition to actuating the recoil system, ultrasonic communication within the weapon may also enable other actuators, such as magazine capture, magazine release, aiming motion, or other simulated effects on the weapon. The advantage of using ultrasonic communication is that communication on all weapons can be done wirelessly, making packaging easier, cleaner, and less modification to the weapons.

Although the specification has explained embodiments with reference to specific drawings and examples, these descriptions are merely exemplary and should not limit the full scope of the embodiments claimed below.