Patent Publication Number: US-2022221257-A1

Title: Geometrically paired live instrumentation training hand grenade

Description:
This application claims the benefit of and is a non-provisional of co-pending U.S. Provisional Application Ser. Nos. 63/104,204 and 63/104,206 both filed on Oct. 22, 2020, which are both hereby expressly incorporated by reference in their entirety for all purposes. 
     This application expressly incorporates by reference U.S. application Ser. No. 17/508,631, filed on Oct. 22, 2021, entitled “AUTOMATED EQUIPMENT ASSOCIATION SYSTEM”, in its entirety for all purposes. 
    
    
     BACKGROUND 
     This disclosure relates in general to battlefield simulation systems and, but not by way of limitation, to training munitions. 
     Conventional systems for simulating hand grenade threat effect simulation utilize laser and short-range radio to determine an affected area of the grenade blast. However, such solutions present problems that reduce the realism of the simulation. For example, laser relies on line of sight, and as a result is unrealistically blocked by items (e.g. foliage, furniture, lightweight street scape, etc.) that would have limited and/or no effect on an operational grenade effect. For example, a thin plastic sheet can shield a laser detector from a laser emitted by a simulated grenade blast, but a blast from a real grenade would not be shielded by such a sheet of plastic. Short-range radio operates in a non-line of sight manner, which mitigates some disadvantages associated with the use of lasers. However, the radio media has the unrealistic effect of diffracting (bending) around a surface and/or reflecting off adjacent surfaces resulting in a simulated effect onto an entity where an operational grenade would have had no effect. For example, one or more soldiers in a concrete-walled corridor can throw grenade(s) around the door into a room. While an operational grenade blast would not affect those soldiers, an RF simulated threat effect is likely to, as the RF signal can bend and/or reflect off a surface to reach an RF detector worn by the soldier. Additionally, existing training grenades can be difficult to find after deployment. 
     SUMMARY 
     In one embodiment, the present disclosure provides method and apparatus for simulating a hand grenade in a training environment. The hand grenade includes dead reckoning to determine location after leaving a thrower. By knowing a location of the thrower and subsequent path after leaving the thrower, the explosion location and simulated damage to targets can be determined. The simulation can determine the effect of obstructions between the explosion location and nearby targets. 
     In another embodiment, a method of operating a simulated hand grenade is disclosed. A first location of deployment of the simulated hand grenade is determined. A second location of a simulated explosion of the simulated hand grenade is determined using dead reckoning. An explosion effect of the simulated explosion for a target within an explosion area of the simulated hand grenade is determined. The explosion effect is communicated to the target. 
     In another embodiment, a method of operating a simulated hand grenade is disclosed. A location of deployment of the simulated hand grenade is determined. A flight path of the simulated hand grenade is determined upon deployment. It is determined that a fuse duration of the simulated hand grenade has expired. An explosion location of the simulated hand grenade is identified after the fuse duration has expired. The explosion location being identified based at least in part on the location of deployment and the flight path. The explosion location is sent away from the simulated hand grenade for subsequent determination of an explosion result of the simulated hand grenade. 
     In another embodiment, a simulated hand grenade is disclosed that includes a trigger mechanism, an arming mechanism, a dead reckoning function, a communication interface, and a processing unit. The trigger mechanism that, when engaged, configures to activate a fuse timing mechanism. The arming mechanism that, when engaged, configures to maintain the trigger mechanism in a safety state in which the trigger mechanism cannot be engaged and, when disengaged, configures to place the trigger mechanism into a live state in which the trigger mechanism is engageable. The processing unit that is configured to:
         detect a location of deployment of the simulated hand grenade;   determine a flight path of the simulated hand grenade upon deployment;   determine that a fuse duration of the simulated hand grenade has expired;   identify an explosion location of the simulated hand grenade after the fuse duration has expired, the explosion location being identified based at least in part on the location of deployment and the flight path; and   provide the explosion location to a remote computing system for subsequent determination of an explosion result of the simulated hand grenade.       

     Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating various embodiments, are intended for purposes of illustration only and are not intended to necessarily limit the scope of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure is described in conjunction with the appended figures: 
         FIG. 1  depicts a block diagram of an embodiment of operation of a simulated hand grenade; 
         FIG. 2  depicts a block diagram of an embodiment of a simulated hand grenade; 
         FIG. 3  depicts a block diagram of an embodiment of a wireless module; 
         FIG. 4  illustrates a flowchart of an embodiment of a process for an association process for establishing a connection between a wireless module and other wireless modules and/or a grenade based on authorization; 
         FIG. 5  illustrates a flowchart of an embodiment of a process for operating simulated hand grenade; and 
         FIG. 6  illustrates a flowchart of an embodiment of a process for simulated hand grenade deployment. 
     
    
    
     In the appended figures, similar components and/or features may have the same reference label. Where the reference label is used in the specification, the description is applicable to any one of the similar components having the same reference label. 
     DETAILED DESCRIPTION 
     The ensuing description provides preferred exemplary embodiment(s) only, and is not intended to limit the scope, applicability or configuration of the disclosure. Rather, the ensuing description of the preferred exemplary embodiment(s) will provide those skilled in the art with an enabling description for implementing a preferred exemplary embodiment. It is understood that various changes can be made in the function and arrangement of elements without departing from the spirit and scope as set forth in the appended claims. 
     Embodiments described herein are generally related to a system and method to improve fidelity of live ground simulation of hand grenade effect or other similar training munitions. In particular, some embodiments of the disclosure incorporate dead reckoning systems into simulated hand grenades, permitting the simulated hand grenade to determine the location at which a simulated detonation occurs. This location can be provided to another computing device, such as a host computer that is running a combat simulation remotely, in real-time, permitting the computing device to evaluate a result of the detonation based on knowledge of entities and their surroundings that are proximate to the simulated explosion (e.g., whether the detonation has an impact on one or more people or objects within an explosion radius of the simulated hand grenade). By permitting the computing device to analyze the effects of the explosion based on a known location of the simulated grenade, line of sight and RF diffraction/reflection issues associated with earlier systems can be eliminated. While discussed primarily in the context of simulated hand grenades for combat training purposes, alternative embodiments can vary from the embodiments discussed herein, and alternative applications can exist (e.g., tracking other thrown projectiles, such as sporting equipment). 
     To geometrically determine the location of the simulated explosion, embodiments of the disclosure use a known starting location and a determined travel path after release by a user to calculate a final location of the simulated grenade at the time of the simulated explosion. In particular, embodiments utilize the grenade thrower&#39;s location at the time of the release of the simulated grenade and a travel path of the simulated grenade between the pin/spoon release and simulated fuse timeout to determine a location of the simulated explosion. In some embodiments, the travel path of the simulated grenade can be determined based on measurements from an inertial measurement unit (IMU) that is integrated into the simulated grenade. Such solutions permit for an accurate real-time determination of the location of the explosion of a simulated grenade to be made, without the need to know anything about the thrower, other than the location at which the thrower released the simulated grenade. This differs from other projectile weapon simulations, which typically also include a launch platform attitude (bearing, elevation), such as the direction and position at which a barrel of a mortar or gun is aimed at when fired. 
     Embodiments can geometrically pair (thrower, grenade, target(s), etc.) without using attitude of deployment method (i.e., bearing or elevation of thrower/deployment platform). Embodiments also permit a definition of grenade explosion location to be provided, even in the absence of an entity hit report. Embodiments further provide the ability to quickly recover grenade, as the grenade&#39;s actual location (in grass/corner/under equipment, etc.) is communicated to a remote computing device that can provide coordinates of the grenade, a display of where the grenade is, and/or output that can indicate an exact location of the grenade once deployed. Additionally, embodiments provide the ability to reuse the same training grenade that is used during combat simulation exercises to teach correct throw technique by analyzing the path. This is due to the ability to measure the path of an arcing throw, from release through to fly out, to determine a final location of the simulated grenade. The path and location can all be measured, enabling detailed feedback to be provided to the trainee. 
     Referring initially to  FIG. 1 , the operation of a simulated hand grenade  102  according to one embodiment is shown. Here, a user  100  deploys a simulated hand grenade  102 , such as by throwing the hand grenade  102 . To throw the hand grenade  102 , the user  100  must first remove a pin that permits an arming mechanism, such as a spoon, to be maneuvered into an engaged state, such as by the user  100  releasing the arming mechanism. Upon the user  100  releasing the hand grenade  102 , the arming mechanism is engaged, which causes a communications interface of the hand grenade  102  to communicate with a wireless module  103  worn by the user  100 . The wireless module  103  can communicate a location of the user  100 , allowing the hand grenade  102  to know a starting position of its flight path. The hand grenade  102  can then track its flight path (which can involve bouncing and/or rolling against one or more surfaces). The flight path tracking can be done using a dead reckoning system. In some embodiments, the dead reckoning system can include an IMU that is integrated into the electronics of the simulated hand grenade  102 . 
     In addition to the determination of the starting location and flight path  124  of the hand grenade  102 , the release of the hand grenade  102  (and engagement of the arming mechanism) also initiates a timer that simulates a fuse of the hand grenade  102 , which has a preset duration. Upon the expiration of the fuse duration, the hand grenade  102  can determine its present location, which is the location of a simulated explosion  120 , based on the starting location and the flight path  124  up until the expiration of the duration. As illustrated, the hand grenade  102  has come to rest between several exposed users  104 . Also nearby are several protected users  106 , who are positioned behind an armored vehicle  112  or some other obstruction such as a rock or reinforced wall. 
     The hand grenade  102  can communicate the location of the simulated explosion to one or more remote devices. For example, in some embodiments, the location of the explosion can be communicated (such as via an RF signal) to each of the wireless modules  103  on users  100 ,  104 ,  106  and/or equipment  112  (e.g., armored car) within a blast radius  128  of the simulated explosion  120 . One or more individual wireless modules  103  are mounted on each of the users  100 ,  104 ,  106  and/or equipment  112  communicate individually using personal area networks (PAN), local area networks (LAN) and wide area networks (WAN). In other embodiments, the location of the explosion can be communicated to a host computer  114 , such as a computer or server farm that is controlling the combat exercise by way of a LAN or WAN. In such embodiments, the host computer  114  can evaluate a pairing of an explosion effect to the targets (e.g., users and/or objects proximate the blast radius). The evaluation can involve the host computer  114  utilizing knowledge about the effects of the particular type of hand grenade  102  (fragmentary, flash, stun, gas, etc.), along with location information associated with the individual target, and/or knowledge of the environment/terrain proximate the blast radius of the location of the explosion. For example, for a fragmentary grenade  102 , the host computer  114  can be programmed to determine that an exposed human target can be “killed” if within a five-meter unobstructed radius of the location of the explosion and can be injured in some manner if within about a ten-meter radius of the location of the explosion. The host computer  114  can also factor in environment information, and thus can know that protected users  106 , while possibly within one of the damage radii outlined above, are protected by the armored vehicle  112  or other obstruction. This permits the host computer  114  to determine that protected users  106  are safe from harm and/or should be subject to reduced injuries based on their shielded state. Similarly, the host computer  114  knows that unshielded users  104  can be deemed to be killed or injured based on their respective positions relative to the location of the explosion. The resulting explosion effects can then be communicated back to the wireless modules of the affected parties (e.g., users, vehicles, structures, etc.) to provide a realistic simulation experience. 
     Referring next to  FIG. 2 , a block diagram of a simulated grenade  102  or be any projectile munition used in training simulations. Grenade  102  can include a housing  202  that is sized and shaped like a live grenade. The hand grenade  102  can further include an arming mechanism  204  and an arming mechanism  206  that are provided on and/or otherwise affixed to the housing  202 . For example, the arming mechanism  204  is a sensor that detects the presence of a pin that is configured to be removed and/or otherwise disengaged from the housing  202 . 
     When engaged with the housing  202 , the arming mechanism  204  maintains the arming mechanism  206  in a safety state, in which the arming mechanism  206  cannot be engaged. Once the arming mechanism  204  is disengaged, the arming mechanism  206  can be switched from the safety state to a live state in which the arming mechanism  206  can be engaged. The arming mechanism  206  can include a sensor to detect the presence, movement and/or absence of a spoon and/or other feature that can be actuated to engage a fuse timing mechanism  208 . For example, a user can release the spoon to activate the hand grenade  102  and start the fuse timing mechanism  208  that counts down for a predetermined duration. 
     This embodiment includes a battery  220  to power the hand grenade  102 . The battery  220  be charged through a port, wirelessly, and/or energy harvesting (e.g., solar). A hanging clip on the throwing user  100  could integrate the charging cable or wireless charger. When connected to either, the pairing to the PAN, LAN and/or WAN can be performed to permit communication to and from the hand grenade  102 . 
     Embodiments can optionally include a tracking tag  224  associated with an indoor tracking system as location determination is commonly most accurate outdoors. The tracking tags  224  can use ultra-wide band (UWB) technology to determine location of the hand grenade  102  and/or wireless modules  103 . Indoor beacons can be used with the tracking tag to allow indoor trilateration of location for the wireless modules  103  and/or tracking tag  224 . In any event, the location of the hand grenade  102  prior to throwing is known throughout the training environment 
     The hand grenade  102  includes dead reckoning functionality in an inertial measurement unit (IMU)  212 . Additionally, the IMU  212  can determine the surroundings while in movement using LIDAR, radar, ultrasonic, and/or camera sensors to develop a point cloud or other simulated reconstruction of the blast radius  128 . Reconstruction information can be shared with wireless modules  103  to distribute the task of building an accurate simulation of the actual environment. Pattern recognition and machine learning can be used to estimate how the various obstructions would react to the simulated explosion  120 . 
     The throwing technique of the user  100  can also be evaluated by the IMU  212 . Use of hand grenades  102  entails recording of training including the throwing style, accuracy and distance for later evaluation of how each grenade simulation was done. The processing unit  214  stores this information for later analysis. Automated suggestions can be provided in real-time during the simulation to provide the user  100  timely feedback, for example, “grenade missed target”, “at that distance throw underhanded”, “use more force to reach that distance”, etc. 
     The hand grenade  102  can also include a communications interface  210 , such as one or more RF antennae or laser/light communication sensors. The communications interface  210  can be armed, such as upon engagement of the arming mechanism  204 , to communicate with the wireless modules  103  affixed to the person throwing the hand grenade  102  to retrieve position information of the user, and thereby the starting location of the hand grenade  102 . For example, the communications interface  210  can poll and/or otherwise request the location from the IMU  212 . In other embodiments, the hand grenade  102  can be passive without independent location determining functionality and can receive a location that is determined from an IMU  212  within the wireless modules  103 . The hand grenade  102  is paired with the wireless modules  103  of a PAN for the thrower using Bluetooth™ Low Energy, Zigbee™, LoWPAN™, WiFi, IrDA™ NFC, and/or any other short-range communication medium. 
     As the arming mechanism  204  is released, the IMU  212  can also be triggered to start detecting movement (the flight path  124 ) of the hand grenade  102 , which can include a flight path  124 , as well as any bouncing and/or rolling against objects during the countdown of the fuse timing mechanism  208 . In some embodiments, the IMU  212  can include a dead reckoning device, which can include an accelerometer, magnetometer, digital compass, gyroscope, pressure sensor, and/or other sensors that enable the IMU  212  to track movement of the hand grenade  102  after deployment. 
     Once the fuse duration of the fuse timing mechanism  208  expires, the hand grenade  102  can determine its absolute position. This can be done using a processing unit  214 , which can take the starting location from the communications interface  210  and the flight path as determined by the IMU  212  and use this information to calculate a position of the hand grenade  102  at the time of detonation. Once the detonation position is determined, the communications interface  210  can send the location to a remote computing system, such as a host computer  114 , for subsequent determination of a result of the explosion (such as whether any targets and/or friendlies were harmed by the simulated explosion). In other embodiments, the communications interface  210  can communicate a signal of the detonation to one or more sensors (such as RF and/or laser detection sensors worn by users and/or positioned on vehicles) that are in a blast radius of the hand grenade  102 . For example, the hand grenade  102  can transmit a detonation location to the target(s), which can evaluate their proximity (line of sight along with any obstructions from terrain and/or infrastructure) and resulting pairing and casualty/damage assessment (explosion result). 
     In some embodiments, the hand grenade  102  can also include a detonation emitter  216  that can include a visual and/or audio emitter. For example, pyrotechnics, light elements, and/or speaker devices can be included in the detonation emitter  216  that allow for an audio and/or visual effect that can be triggered upon the expiration of the fuse timer. A piezo emitter, speaker, LED strobe or light, can be used for the detonation emitter  216 . This permits the hand grenade  102  to more realistically simulate a real live grenade, while still providing a safe, reliable, and reusable form factor. Additionally, not only does sending the detonation location allow the host computer  114  to evaluate explosion results, the detonation location allows the hand grenade  102  to be easily retrieved after completion of the training exercise. The detonation location along with any updates can be communicated with users  100 ,  104 ,  106  locally to allow one of them to easily retrieve the hand grenade  102 . Where the hand grenade  102  communicates directly with wireless modules  103  for users  100 ,  104 ,  106  and/or equipment  112  within a blast radius  128  of the simulated explosion  120 , it allows localized calculation in any of these devices of the resulting casualty/damage outcome to distribute evaluation of the hand grenade  102  effect. Some embodiments do not have a host computer  114  to distribute the simulation computing or as a backup when the host computer  114  is unavailable or excessively delayed. 
     The hand grenade  102  and/or the wireless modules  103  could have terrain and infrastructure information to simulate locally the resulting outcome without use of the remote host computer  114 . Lidar, radar, sonic, camera, and/or other sensors in the hand grenade  102  and or wireless modules  103  could develop a point cloud of the environment along with an estimation of how the simulated explosion  120  would propagate in consideration of obstructions in the blast radius  128 . For example, a cinder block wall can provide better cover than a tent wall. Pattern recognition could be used to tell the difference between various obstructions. For example, a camera or Lidar sensor on the hand grenade  102  could capture scene information in flight or as it rolled or bounced on the floor. 
     For retrieval, the communication interface receives a remote command to activate the detonation emitter  216  to permit easily finding it. Additionally, the location is known by either dead reckoning or through a location determining circuit in the IMU  212 . The circuitry of the detonation emitter  216  could emit sounds and/or light to aid in quickly finding the hand grenade  102 . Some embodiments could include a vibration transducer in the detonation emitter  216  for activation with the simulated explosion  120  or during recovery efforts. 
     With reference to  FIG. 3 , a block diagram of an embodiment of the wireless module  103  is shown. The wireless module  103  is attached to a part of a platform that can include other similar wireless modules  103 . The platform can be a human body  100 ,  104 ,  106 , a vehicle  112  such as a truck, combat system, transit system, warship, etc. The wireless module  103  is configured to identify movements of the wireless module  103  and correlate the movements with the movements of other wireless modules  103  and the platform on which it is attached. The wireless module  103  includes a processing unit  214 , an inertial measurement unit (IMU)  212  a laser detector  328 , an Infrared radiation (IR) interface  338 , a communications interface  210 , a battery/power supply  220 , and a solar supply  342 . 
     The processing unit  214  controls poll initiation, profile detection, correlation, and authorization. The processing unit  214  can include one or more processors, such as one or more special-purpose processors (such as digital signal processing chips, graphics acceleration processors, and/or the like), one or more input devices  330 , and one or more output devices  332 . The processing unit  214  includes a data cache  334  that can include instructions and/or rules that are used by the processing unit  214  to establish PANs. For example, the data cache  334  can include gait information and/or other movement information such as vehicle acceleration, orientation, deceleration, and/or turning profiles that permit the processing unit  214  to properly determine whether a set of one or more other wireless modules  103  are attached to a same body or platform. The processing unit  214  further includes a poll initiator  304 , a profile detector  306 , a correlator  308 , an authorizer  310 , a network organizer  312 , and a network interface  336 . 
     The poll initiator  304  performs a search for the wireless modules  103 . The poll initiator  304  performs a network polling mode of the wireless modules  103 . The network polling mode is initiated using the network interface  336 . In an embodiment, the network polling includes the wireless module  103  detecting a light source, such as a modulated laser. 
     The network interface  336  is a communication interface, which can include without limitation, a modem, a network card (wireless or wired), an infrared communication device, a wireless communication interface and/or chipset, and/or similar communication interfaces. The network interface  336  can permit data (such as movement data) to be exchanged with a network, other computer systems, and/or any other devices. The network interface  336  can also be used to establish and communicate via the PANs. 
     The network interface  336  in the field communicates using the communications interface  210 . Wireless protocols include Bluetooth™, IEEE 802.15.4, Zigbee, IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), near-field communication (NFC), cellular, other short-range communications, etc. 
     The IR interface  338  is a communications interface, which includes an infrared communication using Infrared Data Association (IrDA) or other protocols. The IR interface  338  provides the infrared communication in the PAN or with devices seeking adoption. 
     The battery/power supply  220  provides power to the components of the wireless module  103  such as the processing unit  214 , the laser detector  328 , and the IMU  212 . The battery/power supply  220  includes physical battery, and subsequent power supply. In some configurations, the wireless modules  103  is hardwired to the platform to avoid need for a battery. 
     The solar supply  342  is the energy harvesting component of the wireless module  103 . The solar supply  342  is used to provide solar energy or other renewable source of energy to the processing unit  214 , the laser detector  328 , and the IMU  212  as an alternative source of energy. Where solar is not currently available, the battery  220  can provide power perhaps charged earlier with solar. 
     The profile detector  306  determines the device profile of the wireless modules  103 . The device profile includes two or more of an orientation of the wireless modules  103 , the movement, acceleration, and timing associated with the wireless modules  103 . The profile detector  306  also determines profiles such as movement, orientation, acceleration, and timing profiles of the platform on which the wireless module  103  is attached to or associated with. The profiles also include pressure profiles or gait information associated with the platform. 
     The IMU  212  determines movement of the detected wireless module  103 . The IMU  212  provides the processing unit  214  with movement data associated with the wireless module  103 . For example, the IMU  212  can include a gyroscope  316 , accelerometer  318 , magnetometer  320 , pressure sensor  322 , GPS module  324 , a digital compass  326 , tracking tag  224 , and/or other sensors. The IMU  212  can provide information from these sensors to the processing unit  214  such that the processing unit  214  can identify other wireless modules  103  having similar movement profiles. The processing unit  214  can then determine that these wireless modules  103  are on a same platform and can establish a personal area network with the various wireless modules  103 . 
     The hand grenade  102  includes a IMU  212  that can not include a GPS module  324  as could a wireless module  103 . Where the GPS module  324  is missing, non-functional or powered down, the location of the hand grenade  102  or wireless module  103  can determine its location inferentially from another wireless module  103  on the same platform and PAN and nearby. The separation can be corrected for by the processing unit  214 . Between synchronizations or when separated, dead reckoning can be used, for example when the hand grenade  102  is thrown. Dead reckoning can be calculated by the processing unit  214  using readings from the gyroscope  316 , accelerometer  318 , magnetometer  320 , and/or digital compass  326 . 
     The correlator  308  receives the movement of the detected wireless modules  103  and other wireless modules  103 . The correlator  308  compares the movement of the wireless modules  103  and other wireless modules  103 . Based on the comparison of the movement of the wireless modules  103 , the correlator  308  further compares the device profile of the detected wireless module  103  with the profiles of the platform on which the wireless module  103  is attached to or associated with. The profiles include movement over time profile, acceleration profile, pressure profile and/or gait information associated with the platform. The correlation is provided to the authorizer  310  for processing. 
     The authorizer  310  validates the detected wireless module  103  for connecting with the other wireless modules  103  in a network based on the correlation. When it is determined that the detected wireless module  103  is placed on the same platform and is in correlation with the other wireless modules  103 , then the detected wireless module  103  is authorized for connection. The authorization is necessary for the wireless modules  103  to connect. 
     The network organizer  312  establishes a PAN based on the authorization. The network organizer  312  establishes a network when the detected wireless module  103  correlates with the other wireless modules  103  and is bassociated with the same platform. 
     The wireless module  103  includes the laser detector  328  configured to detect a particular wavelength of light associated with an object such that the laser detector  328  can determine when the wireless module  103  has been hit by the object. US MILES™ is one of several protocols that can be received. 
     Additional components of the wireless module  103  include a laser transmitter (not shown) with US MILES being one of several protocols that can be transmitted. Inclusion of the laser transmitter in the communication interface  210  gives bidirectional laser communication to the wireless module  103 . The wireless module  103  can also include a precision orientation module (not shown) which senses weapon orientation, as next generation replacement for laser. Inclusion of the precision orientation module makes the wireless module-a weapon simulator. 
     Referring next to  FIG. 4 , a flowchart of an association process  400  for establishing a connection between a wireless module  103  and other wireless modules  103  and/or a hand grenade  102  based on authorization is shown, according to an embodiment of the present disclosure. For establishing an automatic association between several wireless modules  103  and/or hand grenades  102 , an authorization of the wireless module  103  or hand grenade  102  based on the correlation is performed. The depicted portion of the association process  400  starts at block  402  where a network polling for the wireless module  103  or hand grenade  102  is initiated. Several wireless modules  103  within a predetermined distance from the unpaired wireless module  103  or hand grenade  102  are identified. 
     At block  404 , based on the network polling, at least one additional wireless module  103  or hand grenade  102  is identified. The at least one additional wireless module  103  or hand grenade  102  being other than the unpaired wireless module  103 . The wireless modules  103  or hand grenade  102  are attached on a same platform which is identified based on the correlation of movements of the wireless modules  103  and/or hand grenades  102  all experience. 
     At block  406 , movements of the wireless modules  103  and/or hand grenades  102  are identified. The movements are identified for correlation to identify association between the wireless modules  103  and/or hand grenades  102 . The movements correspond with the location, orientation, heading, pressure, acceleration, and/or timing of the wireless modules  103  or hand grenades  102  on the platform. 
     At block  408 , the correlation between the unpaired wireless module  103  or hand grenade  102 , and the others is identified. If there is a correlation between the wireless module  103  or hand grenade  102  and the others, then the correlation with the platform is identified at block  410 . Else, at block  416 , the unpaired wireless modules  103 - 1  are unauthenticated at block  416  if there is no correlation between the unpaired wireless module  103  or hand grenade  102  and others on the same PAN. 
     At block  410 , the correlation of the wireless module  103  or hand grenade  102  with the profiles of the platform is identified. For example, the wireless module  103  or hand grenade  102  can be placed on a human body. Then the wireless module  103  or hand grenade  102  is correlated with a location of placement on the human body  100  along with the other wireless modules  103  or hand grenades  102 . If it is determined that all the wireless modules  103  or hand grenades  102  are on the same platform then, at block  412 , the unpaired wireless module  103  or hand grenade  102  is authorized for connection with the others, or else, at block  418 , the wireless module  103  or hand grenade  102  is unauthorized and the correlation is considered a false positive and pairing to the PAN is reversed. 
     At block  414 , based on the authorization of the wireless module  103  or hand grenade  102 , the PAN is established between all the wireless modules  103  and hand grenades  102 . The wireless modules  103  and/or hand grenades  102  all start communicating with each other and an association between the wireless modules  103  and hand grenades  102  is established. 
     The network polling continues to identify wireless modules  103  and hand grenades  102 . The determination of whether the PAN includes nodes that are not on the platform enables the PAN to be reestablished to include the wireless modules  103  and hand grenades  102  that are determined to be on the same platform. Each platform can develop its own PAN with multiple wireless modules  103  and/or hand grenades  102  in this way. Communication between different PANs can occur by way of a LAN or WAN connection by one or more wireless modules  103  in each PAN. 
     With reference to  FIG. 5 , a flowchart of a process  500  for operating simulated hand grenade is shown. Process  500  can be performed by a computing device, such as host computer  114 , that is controlling a combat exercise. Process  500  can begin at block  502  by determining a location of a simulated explosion  120  of a simulated hand grenade  102 . In some embodiments this can be done by receiving a position of the simulated hand grenade  102  (which can calculate this position as described above) at a time of expiration of a fuse duration of the simulated hand grenade  102 , possibly via an RF signal. In other embodiments, determining the location can include determining that a fuse duration of the simulated hand grenade  102  has expired and/or receiving a location of deployment and a flight path  124  from the simulated hand grenade  102 . The computing device can then determine the location based on the starting location and the flight path  124 . In yet other embodiments, determining the location of the explosion can include receiving signals from a plurality of sensors that have detected the simulated hand grenade  102  at a time of expiration of a fuse duration of the simulated hand grenade  102  and calculating the location of the simulated explosion  120  based on the signals from the plurality of sensors. For example, an RF tracking tag  224  can be incorporated into the hand grenade  102  and can be in communication with one or more beacons. The beacon signals can be used to triangulate and/or otherwise determine a location of the hand grenade  102 . In some embodiments, optical sensors, such as cameras and/or IR sensors that can track a location of the hand grenade  102  and transmit a location to the host computer  114 . It will be appreciated that any combination of the above tracking techniques can be combined to track the location of a simulated hand grenade  102 . 
     At block  504 , the computing device can evaluate an explosion effect of the simulated explosion  120  for one or more users  100 ,  104 ,  106  within a blast radius  128  (an explosion area) of the simulated hand grenade  102 . For example, the computing device or host computer  114  can utilize positions of one or more targets  104 ,  106 ,  112  (which can be provided by the targets themselves) and/or knowledge about the environment (buildings, land, vehicles, trees, other structures, etc.) and the like. For example, in building simulations, the buildings and/or other structures can be effectively modeled by the host computer  114 , allowing for complex analysis of the explosion result based on how the structure would impact (e.g., at least partially protect) any of the targets. This data can be used to determine whether a target  104 ,  106  is hit, killed, injured, damaged, protected, etc. In some embodiments, the explosion effect can be based at least in part on a status of the user  100  who deployed the hand grenade  102 . For example, if the user  100  is marked as killed and/or has a simulated injury that would prevent the user  100  from deploying the hand grenade in real combat, the computing device  114  can disregard the deployment of the hand grenade  102 . In other instances, the user  100  can be injured and/or killed attempting to deploy the hand grenade  102 . In such instances, the computing device  114  can determine that the simulated explosion  120  is at the location of the user  100 , as if the user  100  had dropped the hand grenade  102  upon being shot, rather than at the actual location of the deployed hand grenade  102  or alternatively, not simulate the explosive effect. In instances in which the user  100  is deemed healthy and/or otherwise capable of deploying the hand grenade  102 , the explosion effect can be simulated normally. 
     At block  506 , the computing device  114  can communicate the explosion effect to the one or more entities (i.e., users/platforms). This can include sending a signal to a wireless modules  103  of a user  104 ,  106  and/or vehicle  112  that indicates that the entity (such as a target and/or friendly or user that deployed the hand grenade) was harmed, killed, unscathed, and/or otherwise affected by the detonation. In some embodiments, it will be appreciated that some of all of the exercise simulation control can be integrated into user equipment, such as laser detection sensors, rather than a centralized combat exercise control computer  114 . For example, wireless modules  103  can simulate explosive effect with a model that includes the detonation location and any obstructions. Data from the hand grenade  102  and/or wireless devices  103  can be shared among each other to distribute the computational load among the nearby wireless devices  103  in communication with each other without use of a computing device  114 . 
     Referring next to  FIG. 6 , a flowchart  600  for an embodiment of the hand grenade  102  deployment is shown. The depicted portion of the process begins in block  604  where the training grenade  102  is paired to the platform, which is a user  100  in this case. The hand grenade  102  joins the user&#39;s PAN with one or more wireless modules  103  in block  608 . In block  612 , the user activates the hand grenade  102  by pulling the arming mechanism  204  (for example, pin) and triggering the timer by releasing the spoon  206 . Even if the hand grenade  102  has no native location determining circuit, location can be determined implicitly by receiving location information from a wireless module  103  on the same platform/user. A correction can be made by estimating range and direction of separation between the hand grenade and the location from the wireless module  103 . 
     As the hand grenade travels from the user  100  to where the timer expires, dead reckoning within the hand grenade calculates the travel in block  616  before a detonation location is determined in block  620 . Telemetry from the hand grenade  102  including the detonation location is reported over any wireless networks such as PANs or a LAN in block  624 . The hand grenade  102  can include LIDAR scanning without any moving parts to develop a point cloud in flight. Some embodiments can use a camera in the hand grenade  102  to develop the point cloud. The simulated effect can be modeled on a computing device  114  or in a distributed fashion using one or more wireless modules  103  in block  628 . Some embodiments could use other troop mounted computing devices for the simulation or even handheld tablets or smartphones. In block  632 , the effect determined in the simulation is communicated to nearby wireless modules  103  so that they can react accordingly to disable or impede the user in the training exercise and/or stimulate audio/visual effects (such as augmented or mixed reality overlay) at target and observer entities. 
     Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments can be practiced without these specific details. For example, circuits can be shown in block diagrams in order not to obscure the embodiments in unnecessary detail. In other instances, well-known circuits, processes, algorithms, structures, and techniques can be shown without unnecessary detail in order to avoid obscuring the embodiments. 
     Also, it is noted that the embodiments can be described as a process which is depicted as a flowchart, a flow diagram, a swim diagram, a data flow diagram, a structure diagram, or a block diagram. Although a depiction can describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations can be re-arranged. A process is terminated when its operations are completed, but could have additional steps not included in the figure. A process can correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. When a process corresponds to a function, its termination corresponds to a return of the function to the calling function or the main function. 
     For a firmware and/or software implementation, the methodologies can be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. Any machine-readable medium tangibly embodying instructions can be used in implementing the methodologies described herein. For example, software codes can be stored in a memory. Memory can be implemented within the processor or external to the processor. As used herein the term “memory” refers to any type of long term, short term, volatile, nonvolatile, or other storage medium and is not to be limited to any particular type of memory or number of memories, or type of media upon which memory is stored. 
     In the embodiments described above, for the purposes of illustration, processes can have been described in a particular order. It should be appreciated that in alternate embodiments, the methods can be performed in a different order than that described. It should also be appreciated that the methods and/or system components described above can be performed by hardware and/or software components (including integrated circuits, processing units, and the like), or can be embodied in sequences of machine-readable, or computer-readable, instructions, which can be used to cause a machine, such as a general-purpose or special-purpose processor or logic circuits programmed with the instructions to perform the methods. Moreover, as disclosed herein, the term “storage medium” can represent one or more memories for storing data, including read only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage mediums, optical storage mediums, flash memory devices and/or other machine readable mediums for storing information. The term “machine-readable medium” includes, but is not limited to portable or fixed storage devices, optical storage devices, and/or various other storage mediums capable of storing that contain or carry instruction(s) and/or data. These machine-readable instructions can be stored on one or more machine-readable mediums, such as CD-ROMs or other type of optical disks, solid-state drives, tape cartridges, ROMs, RAMs, EPROMs, EEPROMs, magnetic or optical cards, flash memory, or other types of machine-readable mediums suitable for storing electronic instructions. Alternatively, the methods can be performed by a combination of hardware and software. 
     Implementation of the techniques, blocks, steps and means described above can be done in various ways. For example, these techniques, blocks, steps and means can be implemented in hardware, software, or a combination thereof. For a digital hardware implementation, the processing units can be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described above, and/or a combination thereof. For analog circuits, they can be implemented with discreet components or using monolithic microwave integrated circuit (MMIC), radio frequency integrated circuit (RFIC), and/or micro electro-mechanical systems (MEMS) technologies. 
     Furthermore, embodiments can be implemented by hardware, software, scripting languages, firmware, middleware, microcode, hardware description languages, and/or any combination thereof. When implemented in software, firmware, middleware, scripting language, and/or microcode, the program code or code segments to perform the necessary tasks can be stored in a machine readable medium such as a storage medium. A code segment or machine-executable instruction can represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a script, a class, or any combination of instructions, data structures, and/or program statements. A code segment can be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, and/or memory contents. Information, arguments, parameters, data, etc. can be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc. 
     The methods, systems, devices, graphs, and tables discussed herein are examples. Various configurations can omit, substitute, or add various procedures or components as appropriate. For instance, in alternative configurations, the methods can be performed in an order different from that described, and/or various stages can be added, omitted, and/or combined. Also, features described with respect to certain configurations can be combined in various other configurations. Different aspects and elements of the configurations can be combined in a similar manner. Also, technology evolves and, thus, many of the elements are examples and do not limit the scope of the disclosure or claims. Additionally, the techniques discussed herein can provide differing results with different types of context awareness classifiers. 
     Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly or conventionally understood. As used herein, the articles “a” and “an” refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element. “About” and/or “approximately” as used herein when referring to a measurable value such as an amount, a temporal duration, and the like, encompasses variations of ±20% or ±10%, ±5%, or +0.1% from the specified value, as such variations are appropriate to in the context of the systems, devices, circuits, methods, and other implementations described herein. “Substantially” as used herein when referring to a measurable value such as an amount, a temporal duration, a physical attribute (such as frequency), and the like, also encompasses variations of ±20% or ±10%, ±5%, or +0.1% from the specified value, as such variations are appropriate to in the context of the systems, devices, circuits, methods, and other implementations described herein. 
     As used herein, including in the claims, “and” as used in a list of items prefaced by “at least one of” or “one or more of” indicates that any combination of the listed items can be used. For example, a list of “at least one of A, B, and C” includes any of the combinations A or B or C or AB or AC or BC and/or ABC (i.e., A and B and C). Furthermore, to the extent more than one occurrence or use of the items A, B, or C is possible, multiple uses of A, B, and/or C can form part of the contemplated combinations. For example, a list of “at least one of A, B, and C” can also include AA, AAB, AAA, BB, etc. 
     While illustrative and presently preferred embodiments of the disclosed systems, methods, and machine-readable media have been described in detail herein, it is to be understood that the inventive concepts can be otherwise variously embodied and employed, and that the appended claims are intended to be construed to include such variations, except as limited by the prior art. While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure.