Wireless data communication link embedded in simulated weapon systems

<u>Background Art</u>

0001The present invention relates to simulated weapons and, more particularly, to untethered simulated weapons having a wireless connection with a central simulation computer.

0002A firearms training simulator is a device used to train police and military personnel in the proper use and handling of weapons without having to use actual firearms and ammunition. The firearms simulator is designed for indoor training in a safe environment. An effective firearms simulator duplicates the actual environment as much as possible by using weapons that "look and feel" like the real weapon. The primary objective is to immerse the trainee in a situation so that his responses will be the same as in real life. If this is achieved, the instructor can effectively educate the trainee on the correct responses, actions, and behaviors in extraordinary situations. To facilitate this, the instructor will need as much feedback as possible from sensors or other electronic devices to know the exact state of the trainee's devices, such as feedback from position sensors, trigger sensors, and other similar sensored devices. Currently, this feedback is most commonly accomplished via a wired communication link that limits the full mobility of the trainee. Moreover, many simulators today have multiple devices operating at the same time similar to a network of devices.

0003Weapons training courses provide environments in which users can be trained in the use of weapons or can refine weapons use skills. At such weapons training courses, users may train with conventional firearms, such as pistols and rifles, or other weapons, such as a chemical spray. Regardless of the type of weapon used, training typically includes a zone in which the participant is positioned. The participant then projects some form of projectile from the zone toward a target. One of the most common examples of such a system has a participant firing a pistol from a shooting location toward a bull's-eye paper target. To improve the realism of the weapons familiarization process and to also provide a more "lifelike" experience, a variety of approaches have been suggested to make the weapons range more realistic. For example, some weapons ranges provide paper targets with threatening images rather than the single bull's-eye target.

0004In various attempts to present a more realistic scenario to the participant and to provide an interactive and immersive experience, some training simulators have replaced such fixed targets with animated video images. Typically these images are projected onto a display screen, such that the animated images present moving targets and/or simulated return threats toward which the participant fires.

0005In one such environment, described in <patcit id="pcit0001" dnum="US3849910A"><text>U.S. Patent No. 3,849,910</text></patcit>, a participant fires at a display screen upon which an image is projected. A position detector then identifies the "hit" location of bullets and compares the hit location to a target area to evaluate the response of the participant.

0006In an attempt to provide an even more realistic simulation to the participant, <patcit id="pcit0002" dnum="US4695256A"><text>U.S. Patent No. 4,695,256</text></patcit> incorporates a calculated projectile flight time, target distance, and target velocity to determine the hit position. Similarly, United Kingdom Patent No. <patcit id="pcit0003" dnum="WO1246271A"><text>1,246,271</text></patcit> teaches freezing a projected image at an anticipated hit time to provide a visual representation of the hit. <patcit id="pcit0004" dnum="US20020010021A"><text>US-A-2002/0010021</text></patcit> , which forms a starting point for the preamble of independent claims 1 and 11, discloses a device and a method for integrating an optical gun with a computer game system and within a computer game scenario. The preferred embodiment includes an optical gun, or gun, with a communications interface, such as a USB interface, with the computer game system. The gun has sensors that sense when a player is grasping a gun handle, or the gun is bolstered.

0007<patcit id="pcit0005" dnum="US5788500A"><text>US 5,788,500</text></patcit> discloses an improved battlefield simulation system based upon continuous wave lasers. The system uses continuous wave lasers and high-power light-emitting diodes (LEDs) to simulate weapons. A continuous wave laser energy beam is coded using pulse-code modulation (PCM) and pulse-pause modulation (PPM) so that the agent is uniquely identified, as well as the type of weapon responsible for the light beam. The present system provides improved eye safety, improved sensitivity, improved realism, and improved data transfer.

0008Rather than limiting themselves to such unrealistic experiences, some participants engage in simulated combat or similar experiences, through combat games such as laser tag or paint ball. In such games, each participant is armed with a simulated fire-producing weapon in a variety of scenarios. Such combat games have limited effectiveness in training and evaluation, because the scenarios experienced by the participants cannot be tightly controlled. Moreover, combat games typically require multiple participants and a relatively large area for participation.

0009All prior art attempts to simulate weapons fire have disadvantages and drawbacks. Many of the drawbacks are associated with the necessity for the simulated weapon to be tethered by a control cable to a console in order to transmit signals to determine hits and other related information. Meanwhile, other simulators do not provide an efficient means for monitoring the accuracy of shots fired.

0010What is desired, then, and not found in the prior art, is a weapons simulator assembly that provides the use of an untethered simulated weapon that provides operational feedback for the user.

Disclosure of the Invention

0011Accordingly, the invention provides a weapon simulator assembly and a method of monitoring the status of a weapon simulator in accordance with the appended claims. The present invention provides a weapon simulator having a wireless module or data communication link embedded in the weapon simulator to transmit operational information of the weapon simulator to a central processing unit that also contains a wireless transceiver. The wireless module includes a wireless transceiver that provides a signal using frequency hopping spread spectrum technology. One or more sensors may also be attached or embedded within the weapon simulator, with the sensors being connected to the wireless module. Additionally, the weapon may include a laser module attached to the wireless module.

<u>Brief Description of the Drawings</u>

0012<figref idref="f0001">Figure 1</figref> is a block diagram of a first embodiment of the weapon simulator of the present invention;

0013<figref idref="f0002">Figure 2</figref> is a block diagram of a second embodiment of the weapon simulator of the present invention;

0014<figref idref="f0003">Figure 3</figref> is a block diagram of a third embodiment of the weapon simulator of the present invention;

0015<figref idref="f0004">Figure 4</figref> is a block diagram of a fourth embodiment of the weapon simulator of the present invention;

0016<figref idref="f0005">Figure 5</figref> is a block diagram of a fifth embodiment of the weapon simulator of the present invention; and

0017<figref idref="f0006">Figure 6</figref> is a flow chart illustrating operation of the weapon simulator of the present invention.

<u>Description of the Best Mode</u>

0018Looking to <figref idref="f0001 f0002 f0003 f0004 f0005">Figures 1 through 5</figref>, block diagrams of the various embodiments of the present invention of a weapon training simulator assembly <b>10</b> are illustrated. The preferred embodiment of the weapon training simulator assembly <b>10</b> includes a weapon simulator <b>12</b> that has a wireless connection with central processing unit <b>14,</b> with the central processing unit <b>14</b> acting as the central simulation computer. The weapon simulator <b>12</b> transmits information concerning operation of the weapon simulator <b>12</b> to the central processing unit <b>14.</b> More specifically, a wireless module <b>16</b> is either embedded within or attached to the weapon simulator <b>12</b> to transmit the information to the wireless transceiver of the central processing unit <b>14.</b> The wireless module <b>16</b> may be connected to multiple other devices, such as monitoring sensors <b>18</b> or a laser module <b>20,</b> for monitored operation of the weapon simulator <b>12.</b> The wireless module <b>16</b> includes the electronic equipment necessary to provide radio frequency ("RF") transmission, not including an antenna. In particular, the wireless module <b>16</b> includes an embedded microcontroller for controlling RF transmission and can be used for weapon control such as a weapon jam and monitoring.

0019With respect to the wireless module <b>16,</b> it should be noted that wireless technology has been around for many years, and there have historically been two means of transmitting data without a wired connection to a receiver: (1) RF transmissions; and (2) "line of sight" transmissions, such as using light or sound transmissions. The advantage of using RF transmissions is mainly the fact that the receiver does not have to be in the "line of sight" of the transmitter for a transmission to take place. This gives the user the convenience of having a truly wireless system with maximum mobility. Historically, however, equipment for providing RF transmissions has been sizeable, and not capable of fitting into a small space such as a firearm simulator.

0020In order for a wireless RF communication to be effectively used in weapons training, the wireless device has to be low power, low cost, and small enough to fit into the smallest device used in a weapons training simulator assembly <b>10.</b> Such a wireless device was not possible until prior to a new standard of wireless transceivers that became available to the personal computer ("PC") and consumer markets. However, the design of such wireless devices began when the Federal Communications Commission allowed the 900MHz frequency and the 2.4GHz frequency to be license-free to users. However, even with the new equipment, the available wireless transceivers were still not small enough for use in weapons training devices such as handguns. As the digital wireless phones and other wireless devices gained popularity, the need for a standard began to emerge because manufacturers wanted to concentrate on making the transceivers smaller, low power, and cheaper in price.

0021As a result of this demand, two digital wireless standards have taken precedence: IEEE 802.11b for wireless networks and a more generic wireless standard called Bluetooth that was introduced in 1999. More specifically, Bluetooth is a computing and telecommunications industry specification that describes how mobile phones, computers, and personal digital assistants ("PDAs") can easily interconnect for a seamless transfer of information among users using home and business phones and computers using a short-range wireless connection.

0022It should further be noted that Bluetooth may be incorporated into the present invention because it employs frequency-hopping spread spectrum ("FHSS") in signal transmission. FHSS is a modulation technique that repeatedly changes the frequency of a transmission to prevent unauthorized interception of the transmission. The data signal is modulated with a narrowband carrier signal that "hops" in a random but predictable sequence from frequency to frequency as a function of time over a wide band of frequencies. This technique reduces interference because a signal from a narrowband system will only affect the spread spectrum signal if both are transmitting at the same frequency at the same time. FHSS consumes less power and has increased reliability than other transmission techniques.

0023With the new digital wireless standards, manufacturers for the digital transceivers began making these transceivers smaller. In particular, devices that followed the Bluetooth standard had the most promise in being the smallest and least cost since Bluetooth has potentially more widespread use. The smallest version to date is a fully contained Bluetooth module that is about 0.50 inches by 0.75 inches. Moreover, a Bluetooth device provides a less powerful signal in operation than the IEEE 802.11b, and therefore requires less battery power for desired operation.

0024In view of the small size of the wireless module <b>16,</b> the present invention is able to include a wireless module <b>16</b> to solve the problems identified above. In particular, the wireless module <b>16</b> is installed with the weapon simulator <b>12</b> so that information may easily be transmitted to the central processing unit <b>14</b> as needed. This wireless module <b>16</b> is ideal for mounting in any device used in a weapons training simulator assembly <b>10.</b> In addition, the embedded microcontroller of this wireless module <b>16</b> can also be used to interact with the various sensors <b>18</b> of the firearms simulator device <b>12</b> as described herein, as well as the central simulation computer <b>14,</b> which further reduces the electronics required.

0025A low-cost transceiver chip is included in each wireless module <b>16</b> that is used to transmit or receive information. In the present case, the transceiver is in both the central processing unit <b>14</b> and the wireless module <b>16.</b> The transceiver transmits and receives in a previously unused and unregulated frequency band of 2.4 GHz that is available globally (with some variation of bandwidth in different countries). In addition to data, up to three voice channels are available. Each device has a unique 48-bit address from the IEEE 802 standard. Connections can be point-to-point or multipoint, although the maximum range is approximately ten meters. Furthermore, data can be exchanged at a rate of approximately 723 kilobits per second. A frequency hop scheme allows devices to communicate even in areas with a great deal of other radio frequency or electromagnetic interference. Moreover, the wireless module <b>16</b> provides for built-in encryption and verification of transmitted and received information.

0026As discussed above, one or more sensors <b>18</b> will be attached to the weapon simulator <b>12.</b> For example, a pistol-shaped weapon simulator <b>12</b> may include a magazine sensor, hammer sensor, bolt sensor, safety sensor, or a trigger sensor. Such sensors <b>18</b> can take the form of an electrical switch or a mechanical switch, among other embodiments. Each of these sensors <b>18</b> will be linked to a detection unit, which may take the form of interface electronics <b>19</b> monitoring the state of each sensor <b>18</b> (as shown in <figref idref="f0001">Figure 1</figref>), a microcontroller <b>15</b> connected to each sensor <b>18</b> (as shown in <figref idref="f0002">Figures 2</figref> and <figref idref="f0003">3</figref>), or an embedded controller in the wireless module <b>16</b> connected to each sensor <b>18</b> (as shown in <figref idref="f0004">Figures 4</figref> and <figref idref="f0005">5</figref>). The specific operational information provided by each sensor <b>16</b> will therefore either be transmitted to the wireless module <b>16</b> by the detection unit (i.e., the interface electronics <b>19,</b> the microcontroller <b>15,</b> or the embedded controller). Once received by the wireless module <b>16,</b> the signal may easily be transmitted to the central processing unit <b>14.</b>

0027In one embodiment of the invention, the laser module <b>20</b> and associated laser interface electronics <b>21</b> are included to determine the position of the simulator <b>12</b> at the time of firing of the simulator <b>12.</b> However, it should be noted that other sensors might be used in place of the laser module <b>20,</b> such as a gyroscope, that determines the position of the firearm simulator <b>16.</b>

0028The method for monitoring the status of the simulated weapon <b>12</b> is illustrated in <figref idref="f0006">Figure 6</figref>. The method of use begins with the operation of a detection unit. As stated above, the detection unit can take the form of the interface electronics <b>19</b> monitoring the state of each sensor <b>18</b> (as shown in <figref idref="f0001">Figure 1</figref>), the microcontroller <b>15</b> connected to each sensor <b>18</b> (as shown in <figref idref="f0002">Figures 2</figref> and <figref idref="f0003">3</figref>), or the embedded controller in the wireless module <b>16</b> connected to each sensor <b>18</b> (as shown in <figref idref="f0004">Figures 4</figref> and <figref idref="f0005">5</figref>). In any of these embodiments, the detection unit initially monitors the state of each sensor <b>18,</b> as illustrated as step <b>100.</b> At step <b>102,</b> the detection unit determines whether there was a firing event from a trigger sensor <b>18.</b> If there was no firing event at step <b>102,</b> then the central processing unit <b>14</b> must determine if a command was sent to the wireless module <b>16</b> as shown in step <b>104.</b> If a command was sent, then the command is processed as shown in step <b>106,</b> and the detection unit once again monitors each sensor as in step <b>100.</b> If no command was sent, then the detection unit simply begins once again to monitor the state of each sensor <b>18</b> as provided in step <b>100.</b>

0029Referring back to step <b>102,</b> if a firing event did take place, then the detection unit verifies that the condition is suitable to the firing event in step <b>108.</b> In determining whether the simulated weapon <b>16</b> is suitable for the firing event, a number of sensors <b>18</b> may be used to determine the status of the simulated weapon <b>16.</b> For example, a sensor <b>18</b> may determine if a bullet or cartridge is properly loaded into the simulated weapon <b>16,</b> or whether the bolt of the simulated weapon <b>16</b> is in the proper position. If the simulated weapon <b>16</b> is suitable for firing, the laser module <b>20</b> is activated and a laser discharged according to step <b>110.</b> Otherwise, the detection unit weapon returns to step <b>100,</b> and continues to monitor each sensor <b>18.</b>

0030It should be noted that various devices are used in a weapons training simulator assembly <b>10,</b> such as firearms simulators, motion tracking devices, or other similar devices, to enhance training of a student. Such devices are typically connected by a serial or parallel data wired connection, and these devices can be many for each student. Eventually, as the number of devices increase, the mobility of the student can be significantly restricted. This in turn will make the simulator less ideal since real life situations cannot be achieved.

0031Examples of various weapon simulators <b>12</b> that benefit from the incorporation of a wireless module <b>16</b> include the following:

00321) A weapon simulator <b>12</b> such as a handgun with various diagnostic sensors can be completely free of external wires for data communications and control using a wireless link such as a wireless module <b>16.</b> This wireless weapon simulator <b>12</b> can give the user maximum freedom of movement and will give the same "look and feel" as the real weapon while providing the instructor with the exact state of the weapon.

00332) A crowd control device simulator such as a stun gun or chemical spray can be completely free of external wires for data communications and control using the wireless module <b>16</b> as a wireless link. This allows for maximum freedom of movement while providing important training requirements such as ineffective stun gun or an emptied chemical spray.

00343) Peripheral device simulators such as binoculars and laser range finders carried by military personnel can be completely free of external wires for data communications and control using a wireless link such as a Bluetooth device. This will allow for both maximum freedom of movement and the most realistic training.

00354) A position tracking device such as a gyro/accelerometer combination can be completely wireless using a wireless link to allow a student to have maximum freedom of movement and minimum intrusion of the tracking device.

00365) Various sensors worn by the student, such as a holster sensor determining the presence of the firearm, various room sensors that can detect a person's presence, or hit sensor can be completely wireless using a wireless link to minimize on entanglement and maximize the freedom of movement.

00376) A keypad used by the trainee to navigate through the courses offered at his/her own pace could be wireless using a wireless link to minimize entanglement and maximize the freedom of movement.

0038One of the main purposes for a serial or parallel data connection is to allow complete control of the device to the central simulation computer <b>16.</b> The device can send measured data for the student's diagnostics and it can be commanded to perform tasks to provide complete interactivity.

0039In one example of the use of the present invention, a wireless module <b>16</b> is operated as a serial cable replacement. In particular, by connecting the transmit data ("TXD") and receive data ("RXD") pins of the Universal Asynchronous Receiver/Transmitter ("UART") of the wireless module <b>16</b> with the respective TXD and RXD pins of the weapon's microcontroller <b>15,</b> with Clear-to-Send ("CTS") and Request-to-Send ("RTS") connected, a 3.3 VDC supply, and 2.4GHz, 50 Ohm antenna, a simple serial cable replacement is made. Flashing the correct firmware to activate the serial connection with the correct baud rate must be done to the wireless module <b>16</b> prior to assembly. Both the weapon's microcontroller board and the wireless module <b>16</b> can be mounted inside a simulator device with a small antenna and battery.

0040In another example of the use of the present invention, a wireless module <b>16</b> operates as the wireless communication link and a microcontroller <b>15</b> for the weapon simulator <b>12</b> (see <figref idref="f0002">Figures 2</figref> and <figref idref="f0003">3</figref>). The Wireless module <b>16</b> has eight GPIO's (general purpose input/outputs) that can be sensor inputs and laser driver outputs to a laser module <b>20.</b> Any simulator device that needs at most eight GPIO's can use this method. A typical pistol simulator will include a magazine sensor, hammer sensor, bolt sensor, safety sensor and trigger sensor, as well as a laser driver output. The output of the various sensors will be connected to one of the eight GPIO's and the laser driver circuit will be connected to another GPIO. A 3.3 VDC supply and antenna will be added to complete the circuit. A connector to the TXD, RXD, CTS, and RTS lines can be added to allow flashing to the microprocessor. The entire package will be the wireless module <b>16</b> with a connector, laser driver circuit, small antenna, and a battery mounted inside the handgrip of a handgun of the weapon simulator <b>12.</b>

0041For experimentation purposes, two evaluation units of the present invention were tested, and latency was measured to be within acceptable limits of the weapons training simulator assembly <b>10.</b> The serial interface was enabled on the evaluation units which allowed us to test the cable replacement concept. A simulated or replicated weapon was connected to the evaluation unit and linked wirelessly to the weapon simulator <b>12.</b> All features of the weapon simulator <b>12</b> were tested and passed, including sensor diagnostics and commands. As a result, a fully functional chemical spray prototype was developed and operated with the wireless module and the weapon controller card. Also, there was a successful effort in porting over the weapon controller card communication firmware into the wireless module.