Weapon simulation systems are commonly used for combat training and/or shooting practice. Such systems are designed to simulate the effects of a specific weapon type with a specific computer-generated target. There are numerous different types of munitions that are compatible with any one weapon, such as a 40 mm grenade launcher (manufacturer independent). Some of these round types include high explosive, airburst, star cluster, flare, smoke, and practice. Because of this, there have been many attempts by firearms simulation manufacturers to create a method for simulating different types of munitions to be used in weapon simulation systems and be able to monitor the type of munition used in the weapon simulation system.
One method for reading different round types on a mortar launcher was using different color charge rings and a compatible color sensor to detect which charge ring is installed on the mortar. The mortar would then communicate via contacts on the mortar and launcher once the mortar had come to rest. This system was limited in many ways. The largest problem was sunlight causing large offsets and incorrect readings with the color sensor. Another issue is the ability to pick up a difference in color. Because the colors had to have a significant difference in wavelength in order to detect each one with no errors, the round types were limited to less than ten. Additionally, communicating via electrical contacts proved to be unreliable due to corrosion and mechanical bounce. Lastly, there was no ability to store any other data on the round such as a serial number or usage data. Other methods for determining different round types suffer from very similar limitations.
Another example of a previous method for detecting round type is described in U.S. Pat. No. 5,201,658. This implementation uses frequency resonance to detect different round types. There are a few disadvantages to using this type of detection. The most notable disadvantage is the inability to convey more information than just the round type. Additionally the round frequency is set by hardware design and cannot be changed without disassembling the round and replacing the resonant circuit.
A system and method for reading and writing data wirelessly from simulated munitions during a weapon simulation scenario includes a simulated weapon that is in electrical connection with a primary simulation computer and an instructor computing station. The simulated weapon includes an insert which will receive a simulated munition. The insert includes an antenna that is connected to an RFID transceiver, with the transceiver further being connected to a weapon controller. An RFID tag is installed within the simulated munition, with the RFID tag storing information about the simulated munition and transmitting that information to the weapon controller via the RFID transceiver when the simulated munition passes the antenna. The weapon controller will further transmit the simulated munition information to the primary simulation computer for proper identification in the weapon simulation.
a is a side sectional exploded view of one embodiment of the simulated munition used in the simulated weapon;
b is a side sectional view of the assembled simulated munition illustrated in
a is a perspective view of a first embodiment of an insert;
b is a perspective view of a second embodiment of the insert;
A system and method for reading and writing data wirelessly from simulated munitions 24 is illustrated in the attached
The simulated weapon 12 has the appearance of an actual weapon, and includes a weapon controller 18 that monitors the operation of various sensors that are used with the simulated weapon 12, such as a magazine present sensor, a trigger sensor, a safety sensor, a hammer position sensor, as well as others as conventionally used with various simulated weapons 12. The weapon controller 18 may be a conventional microcontroller or microprocessor that is able to control operation of the simulated weapon 12, and it is additionally in electrical communication with a radio-frequency identification (RFID) transceiver 20 that is housed in the simulated weapon 12. As discussed further herein, the RFID transceiver 20 is connected with an antenna 28, which will communicate with an RFID transponder tag 26 housed in the simulated munition 24 when the simulated munition 24 is used with the simulated weapon 12.
As a bit of background, RFID is an automatic identification method, relying on storing and remotely retrieving data using the RFID tags 26 or transponders. The RFID tag 26 is an object that can be applied to or incorporated into a product or item for the purpose of identification using radio waves. Some RFID tags 26 can be read from a very close proximity of the transceiver 20, while others may be meters away and beyond the line of sight of the reader, and still others may be accessible hundreds of meters away. Most RFID tags 26 contain at least two parts. The first part is an integrated circuit for storing and processing information, modulating and demodulating a radio frequency (RF) signal, and other specialized functions. The second component is an antenna for receiving and transmitting the signal to the transceiver 20.
Referring back to
Continuing to view
There are two separate processing blocks within the simulated weapon 12 which can run independent of one another. The weapon controller 18 is responsible for controlling all weapon timing of outputs, the reading of various sensors associated with the simulated weapon 12, and communication with the primary simulation computer 14. The RFID transceiver 20 executes commands to the RFID tag or transponder 26 via the antenna 28 and reads the responses from the RFID tag 26. The RFID transceiver 20 packetizes the data received from the RFID tag 26 and sends the data via a serial bus 19 or another electrical connection to the weapon controller 18. The weapon controller 18 reads the data in from the serial bus 19 and interprets the data from the RFID tag 26 as just another sensor. The weapon controller 18 will make decisions on how to fire the simulated weapon 12 based on the data from the RFID tag 26 along with other weapon sensors associated with the simulated weapon 12. The data from the RFID tag 26 gets re-packetized in a different format and sent to the primary simulation computer 14 where it is used for visual feedback to the trainee using the simulated weapon 12.
As an example, if the simulated munition 24 was designed to have a round type such as “Smoke,” then, when the simulated weapon 12 is fired, the primary simulation computer 14 will display smoke on screen corresponding to where the round was fired. However, if the round type of the simulated munition 24 is a high explosive grenade, then the primary simulation computer 14 will display an explosion on screen. Thus, various simulated munitions 24 may be incorporated into the training of the user. The data from the RFID tag 26 is also available to be viewed by the instructor on the instructor's computing station 16. It should further be noted that all of the parts of the system 10 used for RFID (seen within the dotted line in
The RFID tags 26 used in the illustrated system 10 are passive, although it is foreseen that other types of RFID tags 26 may be implemented. That is, RFID tags are generally passive, active or semi-passive. Passive tags require no internal power source, so they are only active when a reader is nearby to power them. In contrast, semi-passive and active tags require a power source, such as a small battery. For passive RFID tags that have no internal power supply, the minute electrical current induced in the antenna by the incoming radio frequency signal provides just enough power for the integrated circuit in the tag to power up and transmit a response. Passive tags have practical read distances ranging from about four inches up to a few almost 600 feet.
In comparison to passive RFID tags, active RFID tags have their own internal power source that is used to power the integrated circuit and to broadcast the response signal to the reader. Communications from active tags to readers is typically much more reliable than communications from passive tags. Due to their on board power supply, active tags may transmit at higher power levels than passive tags, allowing them to be more robust at longer distances and in different environments. Many active tags today have operational ranges of hundreds of meters, and a battery life of up to ten years. Active tags may include larger memories than passive tags, and may include the ability to store additional information received from the reader. Although the embodiments shown herein include passive RFID tags 26, it is noteworthy that an active or semi-passive RFID tag 26 could be implemented for the user to achieve the desired results.
Referring to
Looking to
Once the simulated munition 20 is inserted into the barrel insert 52, the RFID tag 26 will generally be positioned within the circumference of the antenna coil 28. The position of the RFID tag 26 may vary according to the materials in the barrel 54 and the particular application of the simulated munition 26, but it is desirable to have the RFID tag 26 positioned as close to the center of the circumference of the antenna 28 as possible. In the embodiment shown in
One end of the barrel insert 52 is a hollow recess 53 to receive the simulated 40 mm grenade round 40 inside of the barrel insert 52. The transceiver circuit board 20 that controls communication with the RFID tag 26 is located on the simulated weapon 12 where space allows. The coaxial cable 23 connects the antenna impedance matching circuit board 22 with the transceiver circuit board 20. The transceiver circuit board 20 communicates with the weapon controller card 18 via an electronic connection, such as a serial data bus, to relay munitions data.
Utilizing radio-frequency identification for simulated munitions round type detection has many advantages. For example, the RFID tag 26 can be written to or read from at any time as long as it is within range of the antenna 28 connected to the transceiver 20. This provides the advantage of allowing the same hardware to be used in all applications of simulated weapons 12 with only slight changes in the programming of the RFID tag 26. If any data on the munitions round RFID tag 26 needs to be updated, it can be done at any time from a compatible RFID transceiver 20 without requiring an electrical connection to the RFID tag 26. This includes the round type, service history, and usage data. Additionally, the RFID tag 26 may require no power (if passive, as discussed above) and is purchased as a commercial off the shelf part at a very small cost. This provides a large cost savings over custom applications throughout the life of the product. The RFID tags vary in memory capacity from 32 Bytes to more than 256 Bytes. As little as 32 Bytes would allow storage of 255 different round types and several bytes of service history and usage history. The round type could also be expanded larger however more than 255 round types may be excessive. This amount of data storage provides a very large advantage over other round type detection methods. Lastly, due to the wireless and contact-less nature of RFID, there are no mechanical connections to brake or maintain. This allows for a nearly maintenance free product with high reliability.
Although the example of munitions described above was a grenade, it is to be noted that any other munition may be used in the system 10. For example, the simulated munition 24 may take the form of a bullet, a missile, a warhead, or some other type of munition used in practicing the use of a weapon.
A first prototype RFID antenna 28 was built around a plastic tube 52 that allowed a round to be inserted into it for testing. A 40 mm near-production simulated round was used with an RFID tag 26 installed. It had a read range of approximately 2.5 inches from the coil antenna 28 along the centerline of the plastic tube. To test a version closer to production assembly, the barrel insert 52 was made out of nylon with the relief cut 58 for the impedance matching circuit board 22 and the coil antenna 28. This barrel insert 52 was placed into an aluminum tube with a 3/16 inch wall, which closely models a real barrel of a 40 mm grenade launcher. Initially, the simulated aluminum barrel 54 was offsetting the resonate frequency of the antenna 28 enough for the RFID tag 26 to be unreadable. After retuning the antenna 28, the system 10 was tested to have a read range of about three inches from the center of the coil antenna 28 along the centerline of the barrel 54.
Having thus described exemplary embodiments of a METHOD FOR READING AND WRITING DATA WIRELESSLY FROM SIMULATED MUNITIONS, it should be noted by those skilled in the art that the within disclosures are exemplary only and that various other alternatives, adaptations, and modifications may be made within the scope of the present invention. Accordingly, the invention is not limited to the specific embodiments as illustrated herein, but is only limited by the following claims.
This application claims the benefit of priority of U.S. provisional patent application Ser. No. 60/948,183, filed on Jul. 5, 2007, and U.S. provisional patent application Ser. No. 60/968,041, filed Aug. 24, 2007, each said application being relied upon and incorporated herein by reference.
Number | Date | Country | |
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60948183 | Jul 2007 | US | |
60968041 | Aug 2007 | US |