This application claims the benefit of prior U.S. provisional application Ser. No. 61/434,325, filed Jan. 19, 2011, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
 There are many situations in which a helmet, hard-hat, or other protective headgear is essential. For example, many jobs are performed in hazardous areas requiring a hard hat for protection. Some example jobs include building or road construction, manufacturing involving hazardous machinery or materials, logging, and many others. In some of these settings it can be difficult to perfectly police the use of headgear by those personnel in areas that require it. Some may choose not to wear the headgear at all, while others may remove it from time to time even in hazardous situations. When employees or other personnel choose not to wear protective headgear in hazardous situations it exposes those individuals to a greater risk of head injury. In addition, it exposes managerial personnel and company owners to liability that may result from such injuries. Ideally, no personnel would be allowed entry to a hazardous area without having protective headgear in place.
 The challenge of preventing head injuries also extends to athletics. Participation in athletic activities is increasing at all age levels. All participants may be potentially exposed to physical harm as a result of such participation. Physical harm is more likely to occur in athletic events where collisions between participants frequently occur (e.g., football, field hockey, lacrosse, ice hockey, soccer and the like). In connection with sports such as football, hockey and lacrosse where deliberate collisions between participants occur, the potential for physical harm and/or injury is greatly enhanced. Approximately 300,000 athletes incur concussions in the United States each year. This may be a conservative estimate because many minor head injuries go unreported. Although most concussions occur in high-impact sports, athletes in low-impact sports are not immune to mild traumatic brain injury. Head injuries are caused by positive and negative acceleration forces experienced by the brain and may result from linear or rotational accelerations (or both). Both linear and rotational accelerations are likely to be encountered by the head at impact, damaging neural and vascular elements of the brain.
 At the school level, school authorities have become sensitive to the risk of injury to which student participants are exposed, as well as to the liability of the school system when injury results. Greater emphasis is being placed on proper training and instruction to limit potential injuries. Some players engage in reckless behavior on the athletic field or do not appreciate the dangers to which they and others are subject by certain types of impacts experienced in these athletic endeavors. Unfortunately, the use of mouth guards and helmets does not prevent all injuries. One particularly troublesome problem is when a student athlete experiences a head injury, such as a concussion, of undetermined severity even when wearing protective headgear. Physicians, trainers, and coaches utilize standard neurological examinations and cognitive questioning to determine the relative severity of the impact and its effect on the athlete. Return to play decisions can be strongly influenced by parents and coaches who want a star player back on the field.
 The same problem arises in professional sports where the stakes are much higher for a team, where such a team loses a valuable player due to the possibility of a severe head injury. Recent medical data suggests that lateral and rotational forces applied to the head and neck area (for example, flexion/extension, lateral flexion, and axial rotation) are more responsible for axonal nerve damage than previously thought. Previous medical research had indicated that axially directed forces (such as spinal compression forces) were primarily responsible for such injuries.
 Identifying the magnitude of acceleration that causes brain injury may assist in prevention, diagnosis, and return-to-play decisions. Most field measurements assess the acceleration experienced by the player with accelerometers attached to the helmet. The following show some attempts for measuring the impacts to the skull and brain while the player is participating in a sporting activity. U.S. Pat. No. 5,539,935, entitled "Sports Helmet," issued on Jul. 30, 1996 and U.S. Pat. No. 5,621,922, entitled "Sports Helmet Capable of Sensing Linear and Rotational Forces," issued on Apr. 22, 1997 are examples of some of those attempts. Both patents relate to impact sensors for linear and rotational forces in a football helmet. These devices test the impact to the skull of a player. If an athlete suffers a concussion, for example, it will be possible to determine if the relative magnitude of an impact is dangerously high relative to a threshold to which each sensing device is adjusted, taking into consideration the size and weight of the player.
 Another attempt performs testing impact acceleration to the head with an intraoral device which provides acceleration information of the brain in various sports. Other attempts have been made, however all these attempts can be costly to implement and fail to provide full historical medical information to coaches, trainers and medical professionals in real-time for dozens of players at a time on one or more adjacent fields.
SUMMARY OF THE INVENTION
 The present invention relates to a protective headgear such as a helmet or hard hat which is coupled with additional components to detect whether the headgear is being worn by the user. In some versions of the invention, additional features determine the nature of a head impact. Yet other features may allow the headgear to serve as a security device, allowing entry into a facility only if the headgear is in position and if it is properly associated with an authorized individual who is wearing the headgear.
 In one example, the headgear includes a wirelessly linked impact sensing and reporting system. The system may include one or more personnel electronics modules, a sideline or management module, and a remotely served and remotely accessible recording database module. In a preferred version of the invention, the player module is housed within or on a helmet or other form of protective head gear, the sideline (or management) module is housed within the structure of an otherwise standard clipboard, and the database module is accessible via a network, e.g., public or private Internet.
 In the context of a helmet for an athlete, the player module may include a plurality of sensors capable of detecting impact events in multiple axes, a battery, a data memory storage device, a microprocessor and an LED status indicator array. Each player module includes an RF transducer module and an antenna system, capable of establishing a wireless mesh network for reporting the data associated with an impact to the player. A zinc-air primary cell battery is used with the present player module device, but may be substituted by use of a lithium-polymer rechargeable battery or similar.
 In another version of the invention, the sideline module includes a radio system capable of acting as a node on the wireless network and receiving signals from any of the player modules participating on the wireless mesh network in real-time. The sideline module also includes a battery, a data memory storage device, a microprocessor and a display capable of indicating impact information per player on the wireless mesh network, severity of impact, and recommended action in near real-time. The sideline module also includes a loudspeaker capable of generating audible alert tones to attract a coach's attention to incoming information in real-time. A zinc-air primary cell battery is used with the present player module device, but may be substituted by use of a lithium-polymer rechargeable battery or similar.
 In still another version of the invention, the database module includes a database of players and associated impact data arrangeable by name, team, date, severity of impact, frequency of impact, and many other parameters. The database module is so constructed to be accessible via the public or private data network and is configured to provide various degrees of access to its information contents. Access accounts may be configured according to individual, team, division, league, physician, and administrator levels. Each account will be granted access to the appropriate set of data only, and password protection will ensure dissemination of data only to authorized parties.
 In a preferred version of the invention, an example system includes head gear having a proximity sensor, an accelerometer (or other form if impact sensor), a gyroscope, a processor in signal communication with the accelerometer and gyroscope, a memory in data communication with the processor, a transmitter in signal communication with the processor, and a battery that provides power to the processor, the memory, the accelerometer, and the gyroscope. The proximity sensor detects that the helmet or other form of head gear is in place on the head of the player. In some versions the processor causes the impact sensor to be disabled such as by preventing battery power to the sensor when the proximity sensor determines that the helmet is not in place. In other implementations, the impact sensor still operates fully but the player module obtains data for both the proximity sensor and the impact sensor together so that impact sensor data can be matched with proximity sensor data to determine whether the impact data is from an event when the helmet is in place on the head of the player. The data may be evaluated in the player module or otherwise locally on a player-worn module, or may be transmitted to the sideline for evaluation. The processor is also configured to instruct the transmitter to transmit a signal if an acceleration or other impact sensor event above a threshold is sensed.
BRIEF DESCRIPTION OF THE DRAWINGS
 Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings:
 FIG. 1 is a side view of a hard hat with internal sensors.
 FIG. 2 is an exemplary view of a system including a hard hat with keypad and a badge in communication with a computer monitoring system.
 FIG. 3 is a block diagram of the system of FIG. 2.
 FIG. 4 is a side view of an exemplary sports helmet, illustrated as a football helmet worn by a player.
 FIG. 5 is a side view of the helmet of FIG. 4, shown with internal sensors.
 FIG. 6 is a block diagram of an example base unit in communication with remote devices and having an event evaluation system.
 FIG. 7 is an example block diagram of example components of an event evaluation system;
 FIG. 8 is an example screen display illustrating aspects of an event evaluation system.
 FIG. 9 is an example block diagram of an example computing device for practicing embodiments of an event evaluation system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
 Several preferred versions of the present invention are described below, illustrating components and systems for determining whether headgear is properly in position and further for the detection, measurement, characterization, transmission, and reporting of events causing impact forces to be experienced by individuals, for example workers and athletes. As shown in FIGS. 1 and 2, one preferred version is used in the context of a hard hat 11 for construction or other hazardous situations calling for head protection. As shown in FIGS. 4 and 5, another preferred example is configured for use with a helmet or similar protective head gear 10. The descriptions below are generally applicable to either context, as well as other situations in which headgear is worn and it is desirable to detect whether the headgear is in place or to collect information about the wearing of the headgear or acceleration events experienced by the user of the headgear.
 With reference to the example of FIG. 1, the hard hat 11 may take any form but is typically configured to have a relatively rigid outer shell formed from plastic or other materials, generally being somewhat hemispherical in shape. The hard hat may optionally have a brim, and typically includes an internal impact-absorbing suspension system (partially indicated by reference number 18) that also suspends the shell of the hard hat a short distance above the wearer's head. The suspension system typically includes an internal headband 18, which is adjustable and configurable to snugly encircle the wearer's head. With reference to FIG. 4, the athletic head gear is illustrated in the form of a football helmet having features such as a face mask 12 and a chin strap 14. A typical helmet may further include padding arranged on an inner surface of the helmet shell.
 In each case, the headgear (10 or 11) is configured with one or more impact sensors 20, 22, 24 as discussed further below. The preferred headgear also includes one or more proximity sensors 30, 32, 34. As illustrated in FIGS. 1 and 4, three such proximity sensors are shown, with the proximity sensors illustrated as being secured within the helmet shell in substantially the same manner as for the impact sensors 20, 22, 24, encapsulated within a padding element 40, as described below.
 The illustration of FIGS. 1 and 4 are intended to indicate possible locations for the proximity sensors at locations within the helmet shell. Though three are shown, in the simplest version only a single proximity sensor is provided. Alternatively, in even more sophisticated versions more than three proximity sensors may be employed.
 The locations for the proximity sensors may vary as well. Functionally, the purpose of the proximity sensor is to determine whether the headgear is in position and worn by the user. Thus, the proximity sensors may be placed in any location that would allow the sensors to determine that the wearer's head is situated within the headgear. Though illustrated as being within the shell, in other versions proximity sensors may be mounted on the face mask, chin strap, webbing, suspension, or other locations suitable for detecting whether the headgear is in position. Most preferably, however, one or more proximity sensors is positioned within the main portion of the headgear shell, trained to detect whether the head of the wearer is in place closely adjacent the proximity sensor.
 The proximity sensor may take any form so long as it is able to determine whether the head of the user is within the helmet. As one preferred example, the proximity sensor is a capacitive sensor. Capacitive sensors are commonly employed in touch screen computer displays and generally operate to detect the presence of anything that is conductive or which has dielectric properties. Capacitive sensors can be employed with a hard surface material such as is used with touch-screen displays, though the use of such a material may be less ideal when incorporated into headgear. More preferably, the capacitive sensor is incorporated into a flexible material which is then used as a covering for the padding within the headgear such that the capacitive sensor will be in contact with the player's head when the headgear is worn by the user. Similarly, the capacitive sensor may be incorporated into the suspension system 18 at a location expected to contact the wearer's head when the headgear is worn. Ideally, at least one such sensor is positioned toward the front of the hard hat such that it would contact the wearer's head in the vicinity of the forehead.
 Most preferably, several capacitive sensors are used. Where multiple sensors are provided, the system polls each of the proximity sensors to determine whether all or a majority of the proximity sensors detect the presence of a capacitive object such as the wearer's head. If so, then the system determines that any impact events detected by the impact event sensors 20, 22, 24 are related actual events experienced by the head of the wearer as opposed to spurious events experienced by the helmet alone when carried by the player.
 Importantly, when it is not worn headgear may be dropped or banged against a bench, desk, another person, or some other surface. The detected impact parameters for the headgear when not worn can be quite severe, and may commonly be associated with a significant impact event if the same acceleration or other parameters were detected when the headgear was actually in position on the person's head. Accordingly, by associating the impact event data from the impact sensors with the proximity sensor data, the data produced when the headgear is not in position on the person's head can be ignored or otherwise filtered out from the useful data produced when the helmet is in position.
 In another version of the invention, the proximity sensors are in the form of photo-interrupt sensors. A photo-interrupt sensor may include an infrared emitter and a receiver for detecting light from the emitter. In one version, a first side of the headgear (for example, a left side) may include an infrared emitter while a second side of the helmet (for example, the right side) may include an infrared receiver. If the headgear is not worn by the person, the receiver will detect light from the emitter, thereby confirming that it is not in position. Once the person puts the headgear in position, the light beam is interrupted, thereby indicating that the headgear is in position.
 Yet other types of proximity sensors may be employed to detect whether the person's head is in position within the head gear. For example, alternative sensors may take the form of temperature sensors configured to detect the temperature within the headgear, taking into consideration an expected temperature range when the headgear is in place atop a head. Yet other sensors may monitor electrical conductivity, resistance, impedance, reactance, or other parameters which may vary between conditions when the headgear is worn or not worn by a user. The sensors may also detect pressure, indicative of a downward weight of the headgear on the head, or of a snugly fitting headband secured about the head. Any of these or still other sensors may be used as proximity sensors.
 In some versions of the invention, multiple proximity sensor types are used within a single helmet. Thus, for example, a single headgear may include one or more capacitive sensors together with one or more photo-interrupt pairs of sensors. One type or the other may be considered to be the primary or the backup form of sensor. Alternatively, the system may poll multiple sensors to determine that the headgear is in position only if multiple sensors detect that it is in position.
 As described above, the proximity sensor data may be used to prevent the operation of the impact sensors if the helmet is not in position. Alternatively, it may allow the sensors to operate but the sensor module collects and pairs the data from the proximity sensors and the impact sensors to allow the system to determine which impact events are real and which are spurious. That evaluation may occur locally at the sensor module (either mounted on the headgear or in another person-mounted location) or may take place remotely such as on the sidelines as described above.
 Either with the proximity sensors, or alternatively in the absence of the use of proximity sensors, the system may evaluate the impact sensor data to determine whether the headgear was in position at the time of the impact event. An evaluation of impact data collected from user impact sensor devices confirms that there is a boundary of impact parameter values that are likely to be associated with an impact event experienced by headgear that is worn by a person, and that impact events for empty headgear can be quite different. It is therefore possible to compare impact parameters from the sensors against a database of historically valid impact parameters to determine whether the impact event could have been experienced with the helmet in position on the player's head.
 In this alternative version, the base unit 104 preferably includes a database stored in the memory 116, in which the database contains characteristics for valid impact events, with "valid" impact events meaning those that are possible to have occurred with a helmet in position, preferably based on an aggregation of historical data but optionally based on otherwise established boundaries. In one preferred version, the database includes values defining a peak acceleration, a duration of acceleration above a threshold, and a rate of decay of acceleration. Sensed parameters are compared against the peak, duration, and decay values and when the sensed parameters are below or otherwise inconsistent with stored values considered to be valid, the base unit (such as within the event evaluation system 132) concludes that the impact event occurred when the helmet was not in position. In some versions of the invention, the impact evaluation system for determining the validity of the impact event is also paired with the use of proximity sensors as an additional method for determining whether a particular sensed event occurred with a helmet in position, worn by the user.
 As best seen in FIG. 5, the padding may take the form of a plurality of individual padding elements 40 formed in (for example) a rectangular cubic shape. The padding may alternatively be a single integral component or have any other shape configured to provide cushioning between the helmet shell and the player's head.
 The system conveys to an authority figure, preferably a manager, coach or trainer, useful information about the identity of the impacted person, the severity of the impact, and suggested actions for evaluating the condition of the person and for making decisions about the players subsequent status to return to work, to continue to play, or to be referred to a physician's care.
 In some versions, particularly as used in the hard hat context, the system may also be used as a security device and to gather and store information ensuring compliance with hard hat wear requirements. As shown in FIG. 2, the hard hat may include a keypad 50 enabling the user to enter a security code associated with a particular user. Alternatively, the headgear may incorporate a fingerprint reader or other biometric or user input device to enable the system to confirm a particular authorized user is in control of the headgear.
 The headgear may also include a transmitter 52, such as an RFID transmitter (or tag) that is read by a monitoring receiver 70. The receiver 70 may correspond to the base unit 104 as described below, or may be a simplified receiver corresponding to a unit for more particularly monitoring security. The receiver 70 may also be substantially in the form of an RFID tag reader for receiving data transmitted from the tag. The headgear may include internal components in accordance with the block diagram of FIG. 3. Thus, the keypad may be in communication with an internal processor 58 and memory 56 containing programming instructions to interpret the keypad entries and process them accordingly. A power supply 54 such as a battery provides power for the operation of the system. A transmitter is optionally coupled to the processor to send appropriate signals to the receiver 70 or base station 104.
 In an exemplary operation, the wearer enters a code or personal identification number (PIN) into the keypad. If the code or PIN is accepted, the processor enables the transmission of signals to the receiver 70 or base station 104 indicating that the headgear is enabled by an authorized user. Most preferably, the PIN number uniquely associates a single headgear to a single wearer. Once authorized, the processor further determines whether the proximity sensors 30 detect the presence of a wearer's head in sufficient proximity with the headgear. If so, programming instructions within the memory 56 cause the transmitter 52 to send an appropriate signal indicating that the headgear is in place atop the head of the authorized user. As discussed further below, the system thereafter will continue to monitor the impact sensors for impact events, and likewise will continually monitor the proximity sensors to determine whether the headgear is in place.
 In some versions, the security system may evaluate the presence of a badge 60 or similar key card associated with an individual. Some versions of this type may employ an RFID transmitter for the transmitter 52, with another RFID transmitter on the badge 60 (or, alternatively, a magnetic, optical, or other means of reading the badge). An example of this type may omit the keypad as a means of associating the headgear with a particular user, instead relying on a reading by the system receiver 70 that the badge 60 and headgear 11 (via the RFID transmitter 52) are in close proximity with one another at the worksite entry point.
 The system as described above may serve to both confirm that the headgear is associated with an authorized user, but also to ensure that it is in place atop the wearer's head in order to allow entry. Thus, the system 70 may receive a signal from the transmitter 52 and, optionally, the badge 60 to confirm the presence of an authorized person. The system then further allows entry to the facility (by sending an appropriate code to unlock a gate or an approval code to a display screen monitored by a security gate personnel) only if it also receives a signal from the transmitter 52 indicating that the headgear is in position as determined by the proximity sensors. Accordingly, the system ensures that the headgear is in position and that it is used by an authorized individual in order to gain entry to a secure or hazardous area.
 In addition to the proximity sensors, the headgear may further contain impact sensors to monitor for head impact events. In such a version the headgear includes an arrangement of a plurality of low-cost, distributed impact sensors 20, 22, 24 arranged between the inside surface of the player shell and the bottom surface of a padding elements 40 that provide fit and cushioning to the wearer's head. These sensors may alternatively be positioned in other locations, either inside or outside the headgear. For example, they may be located intermediately within the padding element, either at the interface of two laminated elements, or by encapsulation directly within the mass of the padding element. The sensors may also be situated within cavities of the headgear or in the spaces between padding or suspension elements. As illustrated in FIG. 5, the impact sensors 20, 22, 24 are indicated as being encapsulated within padding elements.
 Any of a variety or electronic devices may be used to monitor the headgear for impact or acceleration events. For example, the sensors may be MEMS type impact sensors, MEMS accelerometers, miniature weighted cantilevers fitted with miniature strain-gauge elements, piezoelectric membranes, or Force-Sensitive-Resistors (FSR). The sensors may also include one or more gyroscopes positioned to detect acceleration along one or more axes.
 In one version, the memory 56 stores data associated with the variety of impact/acceleration sensors, including the proximity sensors. The data storage tracks wear of the headgear over time, preferably associating wear to actual clock time in order to maintain a record of actual times of day during which the helmet was worn and not worn. In the event of a subsequent head injury, the headgear wear data is useful to determine whether the headgear was in position on the person's head at the time of the head injury event.
 The sensors employed in the headgear are connected electronically by means of wires or printed flex circuitry to an electronics pod or other similar means, in some versions situated within a primary shell of the headgear, and within the space available between two or more padding elements. In some versions the sensors are communicatively coupled to a receiving unit contained within a chin strap or other such component that may be internal to or external to the helmet shell. The electronics module (or, for sports helmets, the player module) preferably includes electronic components to transmit the data received from the sensors and then pass it along to a remote or sideline receiving unit. Most preferably the data is passed along in real time, although in some versions the data is stored in a memory and downloaded at a later time.
 In one exemplary version in which headgear data is downloaded at a later time, the data from the proximity sensors and impact or acceleration sensors is collected and stored in the headgear memory for later download or transmission. In one version, the headgear further includes a port allowing for wired connectivity (e.g., mini USB or other computer-readable configurations) to facilitate transmission of stored data to a computing device. In other versions, the headgear data is transmitted wirelessly when the headgear is in the vicinity of a checkpoint such as a security post. While any of a variety of transmission means are possible as described above, most preferably the headgear uses a low power protocol such as that used by RFID tags and readers. When the headgear is detected in the vicinity of the security post (such as receiver 70), the headgear data is downloaded by the receiver. The receiver 70 is preferably a computing device having network connectivity (such as the Internet) so that the data from one or more receivers can be further transmitted and aggregated at a remote location.
 An electronics pod (whether in the helmet, the chin strap, or another location) collects, processes, evaluates, and if appropriate, transmits data pertaining to an impact event via radio to one or more other participant nodes of the wireless network to which the player module belongs. This monitoring and tracking example is described below with reference to FIGS. 6-9 in the context of a football helmet monitoring system, but may also be applied to the context of other situations involving headgear, for example that of a hard hat in a construction or other hazardous area as noted above. Thus, it should be understood that concepts below referring to players, helmets, chinstraps, and the like can be readily applied to employees, hard hats, and other such components in other versions of the invention. Likewise, the sideline module described below may alternatively be a management or security module used by a company to monitor its personnel, rather than by a coach to monitor its players.
 The electronics pod contains electronic circuitry having components such as a microprocessor, flash memory, radio module, antenna, and status display LEDs. In the circuit's memory resides a database lookup table for evaluation of sensor data and comparison to combinations of impact levels that represent suspicious likelihood of Mild Traumatic Brain Injury (MTBI) or concussion. The electronics pod is also configured to monitor, evaluate, and/or display system status information such as link to network, battery charge status, and proper system functioning.
 An example sideline module is an electronic data gathering and display device incorporated into a portable enclosure that is easy for a coach, trainer, or other such game official to carry, consult, and interact with during the activities of the practice or game. The sideline module may be in the form of any electronic receiving device, including laptop or tablet computers, mobile phones, or any other such device configurable to receive wireless information. Moreover, the sideline module is described as receiving information directly from the sensor unit, although in some versions of the invention the sensor module may pass its data to an intermediate server or other device which then forwards the information to the sideline module.
 The sideline module includes electronic components arranged into a circuit that allows for participation in the wireless mesh network established by a set of player modules, and specifically for the receipt of data transmissions from the player modules, and subsequently the display of impact event information on a visual display in real-time. The sideline module also produces audible and vibratory alert signals to call attention to the arrival of new data messages in real-time, which are disabled by manual conscious intervention of the coach or trainer, indicating acknowledgement of receipt of impact event data.
 In one embodiment, the sideline module performs the classification of incoming impact data into categories, indicating differing levels of concern and differing levels of urgency of response. The system may employ a color-coded system to indicate the severity of the event, for example in which green indicates the absence of significant impact events for a given player, yellow indicates the need for immediate sideline evaluation of the player, and red indicates a severe enough impact that the player be removed from play and referred to a physician immediately.
 Upon registering a yellow impact event, and upon subsequent acknowledgement of receipt of the message by the coach or trainer, the sideline module, in one embodiment, leads the coach or trainer through a simple protocol for evaluation of the player's condition. Through answering a series of simple Yes or No questions, the sideline module guides the coach or trainer to a limited number of possible suggested actions. These potential outcomes could include immediate referral to a physician for further examination, or a period of bench time observation followed by a secondary guided evaluation before allowing the player to return to play.
 In one embodiment, a durable record of data transactions is received in real-time and is kept independently of the sideline module or modules. Such a database provides players, parents, coaches, trainers, administrators and other stakeholders access to a record of what impact event information was conveyed, when, to whom and about which player. The sideline module is equipped with a wide area network radio module for transmission of a record of all data transactions on the system with time stamp and a record of the actions by coaches and content of player evaluations. A standard 1 way or 2 way pager system is used, which has the benefit of being inexpensive and nearly ubiquitous in availability throughout much of the world. Alternatives to pager radio systems are cellular radios of various kinds and other wide area network wireless connections. The knowledge that this information will be available to stakeholders provides accountability to all stakeholders in the health and well being of the player.
 In one embodiment, the database is populated by an automatic interface to the wide area radio network accessed by the sideline network, and is accessible to stakeholders by means of internet based applications, equipped with password protected hierarchical account structures. The system provides parents the ability to log on to their account and review the totality of impact event data and the record of coach responses associated with their player.
 Each player module at the start of each season maps its unique identifier code to a particular player's name and number. It is possible that during the course of events players might accidentally wear the wrong player number and potentially cause confusion by users of the system. It is for this reason that each player module has, in one embodiment, a visual indicator array of LEDs, which will repeatedly flash a visible signal in case of transmission of an impact event of concern. A yellow light flashes to indicate the transmission of a yellow event, and a red light flashes to indicate the transmission of a red event. When the player is called to the sidelines for evaluation, the coach or trainer can disable the flashing indicator light by simultaneously depressing a button on the player module and a button on the sideline module. This provides positive confirmation that the player who sustained the reported impact is in fact the player being evaluated by the coach or trainer.
 FIG. 6 illustrates an exemplary system 100 that performs aggregation of sensor information such as head-acceleration information or head-rotational information received from a plurality of sensors 102 and makes the sensor information available to relevant parties. The system 100 includes a base unit 104 that is in wireless communication with one or more sensor units 102 and is in wired or wireless communication with one or more devices 106. In one embodiment, the sensor units 102 can be connected to the base unit 104 via a download and charging station wired or wirelessly connected with the base unit 104 (not shown). The base unit 104 includes a processor 112, local memory 116, and a communication component 120. The base unit 104 receives sensor information wirelessly from each of the sensor units 102 and makes that data available to the one or more devices 106.
 In one embodiment, the base unit 104 or any of the devices 106 are in wired or wireless connection with a medical system 124 over a public or private data network 108. The medical system 124 receives sensor data, identification or other information from the base unit 104 or the devices 106 for analysis with regard to stored athlete information and/or storage into the database 126.
 In one embodiment, the sensor units 102 include one or more accelerometers or gyros embedded into a device secured to head gear such as the helmet 10. When a sensor unit 102 has determined that an acceleration or rotational event has exceeded a set threshold, the sensor unit 102 transmits identification information of the individual sensor unit and recorded acceleration information associated with the acceleration event that exceeded the threshold.
 In one embodiment, the communication component 120 of the base unit 104 receives the sensor information from the sensor unit 102 and delivers it to the processor 112. The processor 112 performs a number of optional operations, such as storing the received sensor information into the memory 116, activating an example event evaluation system 132 to analyze the sensor information stored in the memory 116, and/or sends processed or unprocessed sensor information to one or more of the devices 106 or the medical system 124 via the network 108. In one embodiment, the base unit 104 may simply be a wireless router device that would only include maybe just a communication component and a simple router processor.
 The devices 106 may be one of a dummy display that includes a communication component for communicating with the base unit 104 or may be a smart computing device that includes a processor, a display and a user interface, such as a computing tablet device, a personal data assistant (PDA), a watch or any comparable device. The device 106 may also include local memory. The event evaluation system 132 may optionally be located in the local memory of the device 106. The device 106 would process, using event evaluation system 132, the sensor information received from the sensor units 102 via the base unit 104. Typical users of the devices 106 might be a team coach, trainer or local medical professional.
 An example event evaluation system 132 includes an event determination system 128 that receives sensor information and creates a model of the event. To create a model, an example event determination system 128 translates linear and/or rotational forces from the location of a sensor unit 102 to a center of mass of an athlete's head. The model optionally displays the linear and/or rotational forces on the athletes head. The example event evaluation system 132 also optionally includes an injury prediction engine 130. The injury prediction engine 130 is optionally predicts an injury to the athlete by comparing the received sensor information to sensor information stored within the medical system 124. When the injury prediction engine 130 discovers similar sensor information in the medical system 124, then the injury prediction engine 130 uses the medical diagnosis of the similar sensor information in the medical system 124 to predict an injury to the athlete. The event evaluation system 132 includes a user interface 114 to display event and injury prediction information.
 Example embodiments described herein provide applications, tools, data structures and other support to implement an event evaluation system 132 to be used for near real time collection of data. Other embodiments of the described techniques may be used for other purposes. In the following description, numerous specific details are set forth, such as data formats and code sequences, etc., in order to provide a thorough understanding of the described techniques. The embodiments described also can be practiced without some of the specific details described herein, or with other specific details, such as changes with respect to the ordering of the code flow, different code flows, etc. Thus, the scope of the techniques and/or functions described are not limited by the particular order, selection, or decomposition of steps described with reference to any particular routine.
 FIG. 7 is an example block diagram of example components of an event evaluation system. In one embodiment, the event evaluation system 132 includes one or more functional components/modules that work together to process received sensor information. These components may be implemented in software or hardware or both. The event evaluation system 132, includes an event determination system 128 and an injury prediction engine 130 as mentioned with respect to FIG. 6.
 The event determination system 128 includes an event analysis engine 206, an event modeling engine 208, a threshold determination engine 210 and an alert system 212. The event analysis engine 206 is configured to receive sensor information from sensor devices 102 in the form of an indication of an impact parameter such as acceleration and/or rotational information from an event to be analyzed and an indication of the player that experienced the event. The event analysis engine 206 is configured to determine magnitudes and/or vectors of impacts experienced by the player. A magnitude may be determined based on a reading from a sensor or the magnitude may be recreated by measuring, for example, the length of time an acceleration or other measured parameter was above a threshold value and/or mathematically estimating the magnitude of the impact. In one embodiment the parameter is analyzed by matching a graphical representation of the parameter to a known pattern. In yet another embodiment, a graphical representation of the parameter is analyzed for its peak value, it area under the curve and/or its rate of change. The event analysis engine 206 preferably provides processed sensor information in the form and magnitude and/or vector information to the event modeling engine 208 and the threshold determination engine 210.
 The event modeling engine 208 is optionally configured to receive processed sensor information and to create a model of the sensor information on a human form. For example, the event modeling engine 208 creates a vector of impact and a rotational arc on a model skull to display the effect of an event on a players head. The event modeling engine 208 determines the location, with reference to the body, of the sensor unit that transmitted the sensor information. The event modeling engine 208 optionally determines the location of the sensor units 102, with reference to the body, by accessing configuration information stored in the memory 116 of the base station 104 described in FIG. 3, receives sensor location with the sensor information, and/or receives an indication of a sensor location through a user interface such as the user interface 114 described with respect to FIG. 3. The event modeling engine 208 uses the sensor location information and general characteristics of a human head to model the forces that the head experienced. In one embodiment, the actual dimensions of a player's human head are known. The event modeling engine 208 also adjusts the sensor information using one or more algorithms based on the location of the sensor on the player. The event modeling engine 208 transmits the event data to a medical history system 126 to be used in future events and to a mobile device 214 for display.
 The threshold determination engine 210 is configured to compare the received processed sensor information to a threshold value and optionally activate an alert system 212. The threshold determination engine 210 uses a magnitude, an area under a graphical representation of the sensor information, a rate of change and/or a number of total impacts to activate the alarm system 212. The threshold used by the threshold determination engine may be a default setting, a user setting, and/or a setting that is dynamically set in conjunction the injury prediction engine 209 and the medical history system 126. The alert system 212 is configured to send an alert to a mobile device 214, or optionally sound an audible alarm or active a visual indicator such as the LED described above.
 The injury prediction engine 130 includes an event comparison engine 222 and an injury risk predictor 224. The event comparison engine 222 is configured to receive processed sensor data from the event determination system 128. In one embodiment, the event comparison engine 222 receives normalized data from the recreation system 204. The normalized data is preferably in the form of a magnitude and/or vector of an impact. In an embodiment, the event comparison engine 222 also receives rotational data. The event comparison engine 222 is in data communication with a medical history system 126 which stores historical medical and impact data. The event comparison engine 222 compares the normalized data received from the event determination system 128 to previous impacts stored in the medical history system 126. The event comparison engine 222 attempts to match sensor data, player characteristics such as size and weight, number of impacts for a player, and/or prior medical history of the player to previous events in the medical history system 126. One such comparison includes the using the event comparison engine 222 to determine one or more similar impacts, and then to gather their corresponding medical outcome. For example once an impact is determined to be similar, the event comparison engine 222 will determine what medical result happened to a player as a result of the impact.
 The injury risk predictor 224 is configured to receive the sensor data and the related impacts, with corresponding medical results from the event comparison engine 222. The injury risk predictor 224, using all of the received data attempts to predict an injury based on the impact to the player caused by the received sensor data. While not a medical evaluation, this prediction can be used by a coach, trainer, parent, caregiver or doctor to determine a potential injury and then potentially monitor the player, or run medical testing before another impact potentially makes the problem worse. One such prediction algorithm includes the following formula when attempting to predict an injury. The injury risk predictor 224 uses the received most closely related impact data from the event comparison engine 222 and its corresponding medical result, and then sends the medical result to a mobile device 214 as a prediction as to what may be the medical result of the received sensor data. In alternate embodiments the injury prediction engine 130 may be a neural network.
 A user interface 250 is configured to provide a user with information related to the event/impact and to provide information related to injury risk prediction. The user interface 250 is further configured to provide configuration information for the event evaluation system 132, verify that a sensor 202 is connected, and provides assessment tools for trainers, coaches, parents and caregivers in case of an injury. The user interface 250 is further described in FIGS. 10 and 12.
 FIG. 8 is an example screen display illustrating aspects of an event evaluation system. FIG. 8 depicts a user interface 300 that is an interface for interacting with an event evaluation system, such as the event evaluation system 132 of FIG. 7. The interface 300 includes a graphical representation of sensor data, such as acceleration data shown in a screen area 304. Screen area 304 is located in the bottom left corner of the screen, however in alternate embodiments may be located elsewhere on the screen or shown in response to selection of a button (not shown) by a user.
 The interface 300 includes an indication of a player, and optionally contains his/her number and if the system is connected in a screen area 302. The system connected indication includes an indication of connection of the player's sensor device to the system and an indication of whether the helmet is in position on the head of the player. Screen area 302 optionally may be used to indicate to a coach, trainer or a parent that a player's data is not being received by the system. Screen area 302 is located above screen area 304 and shares a top half of the user interface 300 with screen area 306.
 A magnitude of the most recent sensor information is shown in a screen area 306. The magnitude is optionally shown in the form of a dial, but also may include numbers, or other indicating methods. In the preferred version, the presentation is in the form of a partial dial, using colors such as red/yellow/green to indicate when experienced acceleration (or other impact parameter) is within an acceptable range or has heightened to a level indicative of risk of injury. The indication of screen area 306 is configured to quickly display to a coach, trainer, or health care provider the magnitude of the most recent impact.
 A model of the most recent sensor information on a human form is shown in a model area 308. The model area 308 is located in the bottom right corner of the user interface 300. The model includes a rotatable human skull that contains an indication in the form of an area of a vector of impact and an arrow indicating a rotational path of the head. The interface 300 is used to show information to a coach, trainer, caregiver, or health care provider relating to the most recent event. The interface 300 may be used as a tool to determine whether a player has suffered an injury.
 FIG. 9 is an example block diagram of an example computing system 400 for practicing embodiments of an event evaluation system, such as the event evaluation system 132 shown in FIG. 3. In particular, FIG. 9 shows a computing system 400 that may be utilized to implement an event evaluation system 410. Note that one or more general purpose or special purpose computing systems/devices may be used to implement the event evaluation system 410. In addition, the computing system 400 may comprise one or more distinct computing systems/devices and may span distributed locations. Furthermore, each block shown may represent one or more such blocks as appropriate to a specific embodiment or may be combined with other blocks. Also, the event evaluation system 410 may be implemented in software, hardware, firmware, or in some combination to achieve the capabilities described herein.
 In the embodiment shown, the computing system 400 comprises a computer memory ("memory") 401, a display 402, one or more Central Processing Units ("CPU") 403, Input/Output devices 404 (e.g., keyboard, mouse, CRT or LCD display, and the like), other computer-readable media 405, and network connections 406. The event evaluation system 410 is shown residing in memory 401. In other embodiments, some portion of the contents, some or all of the components of the event evaluation system 410 may be stored on and/or transmitted over the other computer-readable media 405. The components of the event evaluation system 410 preferably execute on one or more CPUs 403 and extract and provide quotations, as described herein. Other code or programs 430 (e.g., an administrative interface, a Web server, and the like) and potentially other data repositories, such as data repository 420, also reside in the memory 401, and preferably execute on one or more CPUs 403. Of note, one or more of the components in FIG. 11 may not be present in any specific implementation. For example, some embodiments may not provide other computer readable media 405 or a display 402.
 In a typical embodiment, as described above, the event evaluation system 410 includes an event determination system 412, an injury prediction engine 415, a configuration manager 413, and a UI Manager 416. The event determination system 412 performs functions such as those described with reference to the event determination system 128 of FIG. 4. For example, the event determination system 411 receives sensor information and/or sensor data from sensor units 460 and transforms the sensor information into a model that displays a recreation of an impact on a human head. The injury prediction engine 415 performs functions such as those described with reference to the injury prediction engine 22 of FIG. 7. For example, the injury prediction engine 415 receives sensor information and/or sensor data and uses the sensor information to predict an injury on a human head. The configuration manager 413 provides configuration information to sensor devices 460 and mobile devices 465. The UI Manager 416 performs steps to create the user interface.
 The event evaluation system 410 interacts via the network 450 with (1) a medical history system 455, (2) mobile devices 465 and/or (3) sensor units 460. The network 40 may be any combination of media (e.g., twisted pair, coaxial, fiber optic, radio frequency), hardware (e.g., routers, switches, repeaters, transceivers), and protocols (e.g., TCP/IP, UDP, Ethernet, Wi-Fi, WiMAX) that facilitate communication between remotely situated humans and/or devices. The mobile devices 465 include desktop computing systems, notebook computers, mobile phones, smart phones, personal digital assistants, and the like.
 The embodiments described above may also use either synchronous or asynchronous client-server computing techniques. Also, the various components may be implemented using more monolithic programming techniques, for example, as an executable running on a single CPU computer system, or alternatively decomposed using a variety of structuring techniques, including but not limited to, multiprogramming, multithreading, client-server, or peer-to-peer, running on one or more computer systems each having one or more CPUs. Some embodiments may execute concurrently and asynchronously, and communicate using message passing techniques. Equivalent synchronous embodiments are also supported. Also, other functions could be implemented and/or performed by each component/module, and in different orders, and by different components/modules, yet still achieve the described functions.
 In addition, programming interfaces to the data stored as part of the event evaluation system 410, such as in the API 417, can be made available by standard mechanisms such as through C, C++, C#, and Java APIs; libraries for accessing files, databases, or other data repositories; through languages such as XML; or through Web servers, FTP servers, or other types of servers providing access to stored data. The data store 418 may be implemented as one or more database systems, file systems, or any other technique for storing such information, or any combination of the above, including implementations using distributed computing techniques.
 Different configurations and locations of programs and data are contemplated for use with techniques described herein. A variety of distributed computing techniques are appropriate for implementing the components of the illustrated embodiments in a distributed manner including but not limited to TCP/IP sockets, RPC, RMI, HTTP, Web Services (XML-RPC, JAX-RPC, SOAP, and the like). Other variations are possible. Also, other functionality could be provided by each component/module, or existing functionality could be distributed amongst the components/modules in different ways, yet still achieve the functions described herein.
 Furthermore, in some embodiments, some or all of the components of the event evaluation system 410 may be implemented or provided in other manners, such as at least partially in firmware and/or hardware, including, but not limited to one or more application-specific integrated circuits ("ASICs"), standard integrated circuits, controllers executing appropriate instructions, and including microcontrollers and/or embedded controllers, field-programmable gate arrays ("FPGAs"), complex programmable logic devices ("CPLDs"), and the like. Some or all of the system components and/or data structures may also be stored as contents (e.g., as executable or other machine-readable software instructions or structured data) on a computer-readable medium (e.g., as a hard disk; a memory; a computer network or cellular wireless network or other data transmission medium; or a portable media article to be read by an appropriate drive or via an appropriate connection, such as a DVD or flash memory device) so as to enable or configure the computer-readable medium and/or one or more associated computing systems or devices to execute or otherwise use or provide the contents to perform at least some of the described techniques. Some or all of the system components and data structures may also be stored as data signals (e.g., by being encoded as part of a carrier wave or included as part of an analog or digital propagated signal) on a variety of computer-readable transmission mediums, which are then transmitted, including across wireless-based and wired/cable-based mediums, and may take a variety of forms (e.g., as part of a single or multiplexed analog signal, or as multiple discrete digital packets or frames). Such computer program products may also take other forms in other embodiments. Accordingly, embodiments of this disclosure may be practiced with other computer system configurations.
 Although the techniques of the event evaluation system are generally applicable to any type of sensor data related to a head impact, the concepts and techniques described here are applicable to other types of sensor data to include sensors on other parts of the body and to sensors on other devices like vehicles. Essentially, the concepts and techniques described are applicable to any sensor collection environment. For example in detecting and processing an explosive charge and modeling its effects on a body or during a car accident to predict injuries to a body. Also, although certain terms are used primarily herein, other terms could be used interchangeably to yield equivalent embodiments and examples. In addition, terms may have alternate spellings which may or may not be explicitly mentioned, and all such variations of terms are intended to be included.
 While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.