Patent Publication Number: US-9847007-B2

Title: Method and apparatus for providing policy-based access using an accelerometer

Description:
RELATED APPLICATIONS 
     This application is a continuation in part of U.S. Pat. No. 9,367,976, issued on Jun. 14, 2016 (U.S. patent application Ser. No. 14/838,860, filed on Aug. 28, 2015), incorporated herein by reference. U.S. Pat. No. 9,367,976 is based upon and draws its priority from U.S. Provisional Patent Application 62/043,580, “Methods, Software, and Systems for Providing Policy-Based Access”, filed on Aug. 29, 2015, hereby incorporated by reference. The present application also incorporates by reference U.S. Provisional Patent Application 62/170,668, “Travel Safety Control”, filed on Jun. 3, 2015. 
    
    
     NOTICE OF COPYRIGHT 
     Portions of this patent application include materials that are subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document itself, or of the patent application, as it appears in the files of the United States Patent and Trademark Office, but otherwise reserves all copyright rights whatsoever in such included copyrighted materials. Copyright© 2014-6 Twin Harbor Labs, All Rights Reserved. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention provides systems, apparatus, software, and methods for providing policy-based access to various user resources, such as, but not limited to restricted areas and devices (e.g., machines and vehicles). The present invention has application in the fields of security systems, computer science, and electronic communications. 
     2. The Related Art 
     Many situations in industry, business, and other aspects of modern life require controlled access to particular locations, machines, or other equipment. Often such situations arise because personnel and other individuals can safely or securely access such locations and devices when in possession of one or more devices, such as hard-hats, reinforced foot protection, breathing apparatus, safety harnesses, protective clothing, fire ground safety and rescue gear, and the like. In order to establish such controlled access, a management function, e.g., a safety or security committee, establishes policies setting forth the various requirements and rules to allow individuals access to the locations and devices that fall within the scope of the policy. Establishing and enforcing such policies is often important to protect businesses from theft and insurance claims arising from accidents. 
     Enforcing these policies, however, is not easy. Often personnel trained in the policy and its enforcement must be provided to watch the location or device to detect violators, which necessitates expensive training and outfitting. The personnel must also have authority to intercept potential violators and stop possibly violating actions. Such requirements can create conditions that create further risks by putting employees in conflict, which can create strains in an organization. Moreover, the enforcement process is itself often inefficient, with gaps in coverage or errors in observation of personnel causing violations of access policies. 
     It would thus be useful to have a more automated system of enforcing policy-based access to resources. The benefits of such a system would be the removal, or reduction, of human error in enforcement; the removal of potential conflicting situations between employees; and the reduction in cost to provide needed oversight. But the availability of these systems is severely limited by the need to provide specialized equipment and the limited scope of enforcement. 
     In particular, current systems cannot reliably determine, if at all, whether personnel have necessary equipment (e.g., safety equipment like hard-hats) when seeking access to a policy controlled resource like a construction site or heavy machinery. The present invention meets these and other needs. 
     SUMMARY OF EMBODIMENTS OF THE INVENTION 
     The present invention provides solutions to the above-described limitations of the prior art. More particularly, the present invention provides methods, systems, apparatus, and software that enable the efficient control of policy-based access to resources. 
     In one aspect of the present invention, a safety equipment device is contemplated, the device including a device identifier, which provides a unique identity for the safety equipment device. The device further includes a power source, and a data processor, integrated into the safety equipment device, for transmitting the device identifier over a communications interface, the data processor receiving power from the power source. The device also includes a data storage containing encoded information, the encoded information including the device identifier, the data storage connected to the data processor, and the device could include a location determination means determining the location of the safety equipment. The device includes an accelerometer connected to the data processor, wherein the data processor compares data from the accelerometer to known accelerometer data patterns to determine if the safety equipment is being properly worn; and a communications interface, connected to the data processor, for receiving and sending signals, the signals encoded with the encoded information and with information regarding a presence of the safety equipment device; and the signals exchanged with a special purpose computer configured to monitor the presence of the safety equipment device within a policy controlled area. The special purpose computer could be a smart phone or a remotely located computer. The special purpose computer may control a device to prohibit access to the policy controlled area unless the safety equipment is being properly worn. The special purpose computer could notify a user when the safety equipment is not properly worn within the policy controlled area. Data whether the safety equipment is worn, and a time could be stored in the memory at periodic intervals and this data could be incorporated into the signals exchanged with the special purpose computer when collected or at a later point in time. 
     In another embodiment, a self-identifying device, comprising a device identifier, where the device identifier provides a unique identity for the device; a power source; and a data processor for transmitting the device identifier over a communications interface, the data processor receiving power from the power source. The self-identifying device also could include a data storage containing encoded information, the encoded information including the device identifier, the data storage connected to the data processor; and an accelerometer connected to the data processor, wherein the data processor compares data from the accelerometer to known accelerometer data patterns to determine if the safety equipment is being properly worn. The device also includes a communications interface (which may use the Bluetooth protocol), connected to the data processor, for receiving and sending signals, the signals encoded with the encoded information and with information regarding a presence of the self-identifying device, the signals exchanged with a special purpose computer configured to monitor the presence of the self-identifying device area within a policy controlled. The self-identifying device attached to safety equipment. 
     A method for monitoring the activity of workers which is made up of the steps of searching for radio frequency signals (which could be cellular, Wi-FI, Bluetooth, or other protocols) within a policy controlled area; connecting with a device found during the search using radio frequency signals at the radio frequency found during the search; interrogating the device for its identity and its functionality; if the device is associated with safety equipment, inquiring of the device, using radio frequency signals, for its location and for patterns from an accelerometer; interpreting the patterns from the accelerometer and determining an activity of the worker based on the patterns from the accelerometer; and reporting the activity to a user. The patterns could be related to talking, jackhammering, walking, hammering, or other activities. 
     These details, and still further aspects and advantages, will become apparent to those having ordinary skill in the art when the following Detailed Description is read in conjunction with the accompanying Drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the present invention are described herein with reference to the following drawings, in which: 
         FIG. 1  is an illustration of a user approaching a policy-controlled access point in accordance with the present invention. 
         FIG. 2  is a schematic illustration of a system for policy-based access control in accordance with one embodiment of the present invention. 
         FIG. 3  is a flowchart illustrating one embodiment of the invention. 
         FIGS. 4A and 4B  are flowcharts illustrating one embodiment of the invention.  FIG. 4A  illustrates the activation of a user&#39;s computer-controlled electronic communications device and response to a query from an Access Control Service in accordance with the present invention.  FIG. 4B  is a continuation of the process described in  FIG. 4A . 
         FIG. 5  is a diagram illustrating one embodiment of the device identifier. 
     
    
    
     DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE INVENTION 
       FIG. 1  illustrates one aspect of the invention at  100 . There, the area  106  proximate to a door  104  or other access to a policy-controlled area (not shown) is covered by antennas  108  and  112 . Door  104  can be any sort of portal or other physical barrier or demarcation separating the policy-controlled area from the area outside of such control. Examples of policy-controlled areas include without limitation areas requiring safety equipment such as hard-hats, boots, eye protection, safety harnesses, protective clothing, fire ground safety and rescue gear; and areas requiring specialized tools or other devices. Control of entry into the policy-controlled area can be performed by locking door  104  or other access portal, or by providing an alarm or other notification if unauthorized access to the controlled area is attempted. Antennas  108  and  112  are capable of communicating with a computer-controlled electronic communications device as described herein below. The policy governing the policy-controlled area is any single or group requirements established to determine who and what are able to enter the policy-controlled area. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     User  116  represents anyone seeking access to the controlled area via door  104 , such as a worker, manager, or visitor. The user carries a device  120 , which is necessary for the user to meet the requirements of the policy and pass through door  104 . Device  120  can be anything required to be proximate to the user that is required by the policy governing access to the policy-controlled area as described above. The device further includes a device identifier  122  that identifies the device and, in some embodiments of the invention, provides information about the device and its status. In some embodiments, the device uses Bluetooth communications components and methods; in other embodiments, RFID or near-field communications are used instead of, or in addition, Bluetooth. In more specific embodiments, the device is a Bluetooth tag that is associated with the device. In some embodiments, the tag is detected by the user&#39;s computer-controlled electronic communications device ( 124 ), described in more detail herein below, one or more of the antennas  108  and  112 , or both. In still other embodiments, the invention provides for the detection of unauthorized entry by the passing of unknown or unresponsive (or both) Bluetooth, RFID, near-field, Wi-Fi, cellular signals, or the like, passing an antenna. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     In some embodiments, such as seen in  FIG. 5 , the device identifier  500  includes a power source  503 , communications means for sending and receiving signals  501 , a data processor  502 , and data storage  506  containing electronically encoded information about the identity and properties  507  of said device. In more specific embodiments, the data storage  506  further contains information about the user of said equipment. In still more specific embodiments, the communications device  501  is configured to send and receive Bluetooth signals; in other embodiments, RFID or near-field communications are used instead of, or in addition, Bluetooth. The device identifier  500  may be attached to the safety equipment using and attachment mechanism such as adhesive, zip tie, string, thread, tape, screws, nails, or other mechanical means. The device identifier  500  could be built into the safety equipment. 
     In another embodiment the device identifier  500  further includes an accelerometer  504 . The accelerometer  504  could detect motion patterns and the data processor  502  could compare these patterns to known patterns. For instance, if the device identifier  500  is attached to a hard hat, the accelerometer readings could be compared to the patterns of an accelerometer  504  when worn on the head. This could be used to assure the hard hat is worn and not just carried. Or the accelerometer  504  in a device identifier  500  attached to a pair of goggles at a saw mill could indicate that the goggles were vertical, implying that the goggles were on the face protecting the user&#39;s eyes. 
     In another embodiment, a thermal detector  505  could be incorporated in the device identifier  500 , detecting body heat to determine if the equipment attached to the device identifier  500  is being worn. For instance, the device identifier  500  could be attached to gloves at a band saw, and the thermal sensor  505  could detect if the gloves were on the hands. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     The user also carriers a computer-controlled electronic communications device ( 124 ), such as a smartphone, tablet computer, personal data assistant (“FDA”), or the like. Examples of suitable devices are those using the Android operating system (Google, Mountain View, Calif.) and the iOS operating system (Apple Computer, Cupertino, Calif.). Still other suitable devices and operating systems will be recognized by those having ordinary skill in the art. The device is capable of receiving signals from, and sending signals to, antennas  108  and  112  and device  120 . The configuration and operation of the computer-controlled electronic communications device will be described in greater details herein below. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
       FIG. 2  provides a schematic view of an embodiment of a system aspect of the invention ( 200 ). There, an Access Control Service  204  is in bi-directional communication, either directly or over an electronic communications network  222 , with a Policy and Data Store  208  to provide policy-based control to a policy-based controlled area (not shown). Service  204  is configured to determine the appropriate policy (or policies) controlling access to the area in question, the requirements of the policy (or policies), queries to obtain the information necessary to determine compliance with the policy or policies, and then enable or prevent access to the controlled area. In a non-limiting example, the Access Control Service includes an electronic computer that is configured to execute electronically encoded instructions on electronically encoded data. The electronically encoded instructions are configured to enable the Access Control Service to execute its functions, including those just described. The Policy and Data Store  204  includes electronically encoded data and instructions that are used by the Access Control Service to determine compliance. Thus, the Policy and Data Store includes electronically encoded data and instructions identifying and describing the various policies executed by the Access Control Service. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     The Access Control Service is also in bi-directional communication (either directly or over an electronic communications network) with a portal  212  demarcating the policy-controlled area from non-controlled areas (including areas under control of a different policy or policies). The portal has the general description provided for door  104  in  FIG. 1 . Thus, in some embodiments, portal  212  is a physical barrier that prevents access until a signal or other action from the Access Control Service enables removal or movement of the barrier. In other embodiments, the portal  212  is not a physical barrier, but includes one or more notices or alarms (or both) that are either activated or de-activated by the Access Control Service depending on the result of its analysis as described herein. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     The Access Control Service also engages in bi-directional communication (either directly or over an electronic communications network) with one or more antennas or other devices that enable the transmission of electronically encoded signals between a user  220  and the Access Control Service. Such signals can be transmitted using methods such as cellular communications, Wi-Fi, radio, microwave, and other means familiar to those having ordinary skill in the art. The signals include signals encoded to broadcast the presence of the Access Control Service, which are sent at regular intervals to engage with a user&#39;s computer-controlled electronic communications device ( 124 ) as described herein. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
       FIG. 3  provides an illustration of one exemplary embodiment of a method for providing policy-controlled access in accordance with the present invention from the perspective of the user&#39;s computer-controlled electronic communications device ( 300 ). The device executes a “wait loop” ( 304  in which no action relevant to accessing a policy-controlled area occurs until receiving a signal from the Access Control Service. When the signal is received, the device receives a compliance query from the Service ( 308 ). The content of the query is determined by the data and policies in the Policy and Data Store as executed by the Access Control Service. The user&#39;s device then queries other devices proximate to the user to provide a response to the query ( 312 ). The device then returns an answer to the Access Control Service ( 316 ). The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
       FIG. 4A  illustrates at  400  a more detailed embodiment of the communications between the user&#39;s computer-controlled electronic communications device and the Access Control Service. The user&#39;s device receives a signal from the Access Control Service announcing the presence of the Service as described above with respect to  FIG. 2 . In some embodiments, the signal causes the user&#39;s device to start a Query Response Process ( 408 ). Examples of such activation can be found, e.g., in U.S. Pat. Nos. 7,873,390; 7,929,959; 8,798,677; Chinese Patent Application No. CN103365441; and Published U.S. Patent Application Publication No. 2014/0106734. Each of these patents and patent application is incorporated herein by reference in its entirety and for all purposes. In other embodiments, the Query Response Process is running in the user&#39;s device as an active process or a daemon waiting to be woken to a fully active state upon receipt of the signal. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. Upon activation, however that is accomplished, the user&#39;s device sends an acknowledgment to the Service ( 412 ). The Service then generates the appropriate query or queries, which are received by the user&#39;s device ( 416 ). The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     Turning to  FIG. 4B , the process continues at  420 , where process now running on the user&#39;s device determines the requirements of the query. The user process then identifies the proximate devices ( 424 ). If no device is present, then an appropriate result is returned to the Access Control Service and the process ends ( 428 ,  432 ). If a device (or devices) is (are) present, then the device(s) are queried ( 436 ) and the results are relayed to the Access Control Service ( 432 ). In some embodiments, the results are processed on the user&#39;s device prior to relay ( 440 ). The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     In some embodiments, the user&#39;s device locates proximate devices by searching for electronically encoded signals from the device. In more specific embodiments, the signals are Bluetooth-encoded signals; in other embodiments, RFID or near-field communications are used instead of, or in addition, Bluetooth. In still more specific embodiments, the Bluetooth signals are from “tags” that provide an identifier, such as a serial number or the like, that is associated with a description or identifier of the device. In some embodiments, the user&#39;s device is responsible for determining the identification of the proximate device from the signal, e.g., by referring date stored on the user&#39;s device or by separate query to the Access Control Server, e.g., provided by the Access Control Service with the original query, or through another server. In alternative embodiments, the user&#39;s device relays the identifier to the Access Control Service for processing by the Access Control Service. Still other methods and materials for device identification will be apparent to those having ordinary skill in the art. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     Once the Access Control Service receives the response to the query from the user&#39;s device, the Service processes the query to determine if the policy requirements for access have been met. If the result is affirmative, then the Access Control Service enable access to the policy-controlled area by the user. This can be accomplished by enabling physical access, e.g., unlocking or unblocking a door, or by disabling an alarm or other warning. In addition, in some embodiments the Access Control Service sends a reply to the user&#39;s device indicating approval, e.g., by a sound or visual cue, or both. If the policy requirements are not met, then the Access Control Service prevents access, e.g., by maintaining or initiating a lock or block of a door, or by activating an alarm or warning. In addition, in some embodiments the Access Control Service sends a reply to the user&#39;s device indicating approval, e.g., by a sound or visual cue, or both. The provision of these elements and their operation will be familiar to those having ordinary skill in the art. 
     Example 
     In one illustrative and non-limiting example, a user seeks to enter a policy-controlled work area that requires both a hard-hat and protective boots. The area is separated by a locked door that can be unlocked by a signal from an Access Control Service, configured as described herein, if the necessary policy conditions are met. The user carries a smartphone, such as an Android or Apple iPhone, that is configured to provide the functionalities described hereinabove. 
     As the user enters the uncontrolled area, his (or her) smartphone receives signals from the Access Control Servers that initiate a process to respond to queries from the Access Control Service. When the process is running, it sends to the Access Control Service a response that causes the Access Control Service to forward the query appropriate for access to the controlled area. The process receives the query and determines which devices are needed to demonstrate access. Alternatively, the query simply tells the process to locate all devices proximate to the user. In a second alternative, the query more specifically identifies the devices to boots and a hard-hat. 
     The process then seeks Bluetooth signals proximate to the user; in other embodiments, RFID or near-field communications are used instead of, or in addition, Bluetooth. If no Bluetooth (or equivalent) signals are received, then the process returns that result; the Access Control Service determines the policy conditions have not been met; and sends an exception to the user and maintains the lock. If Bluetooth signals are received, then the process either determines the corresponding identifiers and their corresponding device identities (i.e., if they are from the boots and hard-hat), or the process forwards the corresponding identifiers to the Access Control Service for further analysis. If the Access Control Service determines that the identifiers are sufficient to allow the users to meet the policy requirements for access, then the Access Control Service unlocks the door and sends a corresponding reply to the process, which then notifies the user. If the Access Control Service determines that all of the identifiers are present, but not sufficient (e.g., wrong type of boots or hard-hat), or that at least one identifier is not present (e.g., the hard-hat is present, but not the boots), then the Service denies access as just described. 
     In another embodiment, the computer-controlled electronic communications device ( 124 ) could interrogate other computer-controlled electronic communications devices proximate to the computer-controlled electronic communications device ( 124 ) to see if these other devices have located device identifiers  122  attached to safety equipment. If the computer-controlled electronic communications device ( 124 ) is not connected to similar equipment, the computer-controlled electronic communications device ( 124 ) could sound an alarm. For instance, if the user&#39;s cell phone checks with the nearby cell phones of other users, and finds that everyone else is wearing a hard hat but the user is not, the cell phone would sound an alarm. 
     In another embodiment, a police department could establish a virtual zone around a dangerous situations by defining the protected zone using a location determination system such as IPS, beacons, GPS, Assisted GPS, U-TDOA, directional antennas, or other similar technologies to map out the area. This is the policy-controlled area. A wireless protocol, such as cellular, Wi-Fi, or Bluetooth can then be used to identify all devices (computer-controlled electronic communications device ( 124 )) within the protected zone or that are entering the protected zone. Each police officer runs an app on their cell phones that connects to tags  122  on the equipment that they are carrying. The tags  122  may be placed on the bullet proof vests, their uniforms, various radios and weapons. When the police office enters the protected zone (and while in the protected zone), the cell phone app takes an inventory of the equipment that he is carrying. The app then reports this equipment to a central computer (Access Control Service) that maps where all of the police officers are located along with the equipment they are carrying. This will allow police supervisors to locate needed equipment within the protected zone, such as an officer with a particular weapon. 
     Should the police supervisors decide that all police officers located in the protected zone must be wearing certain equipment, such as a bullet proof vest, then every police officer entering the protected zone will be warned if they attempt to enter the protected zone without the bullet proof vest, and the central computer will be notified if they continue into the protected zone. All police officers within the protected zone at the time that the requirement is set may also be warned that they are not in compliance. This embodiment could also be extended to firefighters at the scene of a fire. 
     Further Embodiments 
     In one embodiment, the Access Control Service  316  could be used to monitor employee work habits and patterns in addition to monitoring their use of safety equipment. The Access Control Service  316  could be tied to the timecard system to determine when workers arrive and depart. The Access Control Service  316 , because it know where an employee is at all times, could also determine how much time the employee spends in the bathroom or on cigarette breaks. It could also monitor how much time is spent standing around talking instead of working. Other useful information that is available is how sets of employees cluster together, allowing managers to know what the de factor teams are in the organization, in a sense monitoring the social clustering of the organization by monitoring the positioning of the safety equipment. 
     By linking to the accelerometer in the helmet, the heads of the users could be monitored to see who is talking by matching the pattern of accelerometer head movements of a person talking against the accelerometer readings. The accelerometer readings of head movements of a person listening to a conversation could also be checked to see who is listening to the conversation. This would allow employers to distinguish those employees who is disrupting the work by talking from a supervisor instructing the employees. In an alternate embodiment, the helmet could be equipped with a microphone that is used to determine who is talking by comparing voice prints without recoding the contents of the conversation. 
     The accelerometer is a good source of information on the activity of the workers. It could be used to deduce how fast the workers are moving, what activity they are performing (shoveling, jack-hammering, walking, hammering) base on the comparison of the accelerometer data with known patterns for those activities. 
     Essentially, the Access Control Service  316  is monitoring employee activity in 3D space. The employee could be monitoring to see when climbing or when moving anywhere in space. Climbing could be detected by the accelerometer movements related to climbing or by watching the accelerometer to see that movement is occurring in the opposite direction as gravity. This would be useful for triggering a check for climbing safety equipment such as fall protection devices and helmets, protecting painters, carpenters, roofers, and tree workers. 
     Helmet 
     There is a description of a helmet with the accelerometer and processor in U.S. Provisional Patent Application 62/170,668, “Travel Safety Control”, filed on Jun. 3, 2015, which is incorporate by reference. In one design, the Cypress PSoC (“Programmable System-on-Chip”) could be incorporated into the helmet (or any other safety equipment) along with sensors to determine if the helmet is being worn. The PSoC chip includes BLE circuitry and the complete BLE stack, and could be coded with a Bluetooth profile to respond to requests from the electronic communications device  124  electronics with the sensor data that provides the indication of whether the helmet is on the users head. The PSoC, sensors, and a battery could be electrically mounted on a small pc board with a small antenna made of traces etched into the board. An on-off switch is optional to save battery, alternatively, the power save mode on the PSoC could be used to keep the board in a deep sleep mode if the helmet is not in motion. 
     This board could be shock-mounted into the inside of the helmet to prevent damage from impacts to the helmet. Additionally, the pc board could be coated in epoxy or similar compound to protect the electronics from water, snow, mud, dust, humidity, and other environmental hazards commonly found with work environments. The temperature in a helmet should be within the operating range of the integrated circuits should the helmet be worn. There is a concern that a helmet left outside in sub-zero weather may not be warm enough to operate, but once the helmet is placed on the user&#39;s head for a few minutes, the temperature should return to operating range, provided that the pc board is mounted inside of the helmet. 
     The BLE chip in the helmet could be paired with the user&#39;s cell phone. The user&#39;s cell phone runs an app that monitors the helmet, collecting accelerometer data from the helmet, and communicating to the Access Control Service  316  data on the location of the user and the data from the helmet. Processing of the accelerometer data to determine whether the helmet is being worn could be done by the BLE chip in the helmet or by the app in the cell phone or by the Access Control Service. The check to see if the helmet is being worn in the safety zone could be done in the BLE Chip, the app, or in the Access Control Service. 
     Because the helmet includes BLE, some embodiments of the helmet could include speakers to provide music to the user or to allow the user to hear messages from other team members. In another embodiment, the speakers could include noise canceling functionality to offer hearing protection to the user. In addition, the helmet could include passive hearing protection as well. In one embodiment, the helmet could also include a microphone to allow two-way communication. The microphone could also be used to tell which employee does most of the talking when the workers are found not to be working. 
     Data collected by the helmet on the use of safety equipment and the location of the user could be transmitted immediately to the Access Control Service or it could be stored in the helmet (or cell phone) and uploaded at a later period of time. 
     In another embodiment, the accelerometer data could be transmitted through a mesh network of helmet BLE chips throughout the workspace to the Access Control Service through some form of network. 
     Determining Location 
     Much of what is occurring in this concept is the determination of people in a 3D space. But how do we determine where they are. In one embodiment, the cell phone is used with its GPS and cell tower locator technology. In another embodiment, various technologies can be used to determine where the cell phone or helmet (or other safety equipment) is located in the 3D space. Directional antennas or distance antennas coupled with movement information could be used to locate the constellation of devices. 
     If the location, or safety equipment has a GPS, IPS or other method of determining its exact location, then the absolute coordinates can be determined. In the helmet, if the electronics also includes a compass, then the angle can be resolved to compass direction instead of only relative to the direction that the user wearing the helmet is facing. The accelerometer can determine angle to the ground by looking to the access that is seeing the effects of gravity. This allows the determination of which way the user is facing and the location of the user. This can be used to determine the user&#39;s activity, such as facing a machine if working or facing other workers if talking. 
     To determine the mapping of an indoor location, Google is working on a project to map the inside of public places with the same camera system that was used to take pictures of roads. Alternatively, most towns have the database of the boards of assessors online. Many of these databases include floor plans for all buildings in the municipality. In one embodiment, the communications in the helmet could be Wi-Fi, and a Wi-Fi router could be used as the beacon for the building. Assuming that a router is rarely moved, once its location is established within a building, then every Wi-Fi device is the building can be monitored as to its location. The Wi-Fi router would need to have its antenna replaced with a directional antenna and software to read the direction and distance (using ToF or RSSI) that the signal originated from. With that, the router would know the location of all Wi-Fi devices in the building. 
     CONCLUSION 
     The above description of the embodiments, alternative embodiments, and specific examples, are given by way of illustration and should not be viewed as limiting. Further, many changes and modifications within the scope of the present embodiments may be made without departing from the spirit thereof, and the present invention includes such changes and modifications.