Patent Publication Number: US-9886013-B2

Title: Wireless network of low power sensing and actuating motes

Description:
DOMESTIC PRIORITY 
     This application is a divisional of the legally related U.S. Continuation application Ser. No. 13/965,382 filed Aug. 13, 2013 which claims the benefits of the legally related U.S. Non-Provisional patent application Ser. No. 13/790,006 filed Mar. 8, 2013, both of which are fully incorporated herein by reference. 
    
    
     BACKGROUND 
     Exemplary embodiments relate to wireless sensing and actuation networks, and more specifically, to methods and systems for providing a network of low power sensing and actuating motes. 
     In general, motes are small low-power computers that are configured to act as sensors. Currently available motes are configured to communicate with a central computer via a radio link. Common radio links allow a mote to transmit a distance of approximately 10 to 200 feet. The distance is typically limited by power consumption, size and cost constraints. Mote networks are currently used for a variety of applications and the motes may include Global Positioning System (GPS) sensors for use in identifying the location of each mote in the mote network. 
     SUMMARY 
     According to an exemplary embodiment, a wireless mote network having a plurality of motes, wherein each of the plurality of motes includes a processing unit in communication with a communications device. Each of the motes includes at least a sensor configured to monitor an environmental condition in an area around the mote or an actuator configured to control one or more external systems. The wireless mote network also includes a central communications device configured to communicate with one or more of the motes within a range of the central communications device and a controller configured to communicate with the central communications device, to receive one or more signals indicative of the environmental condition of one or more of the plurality of motes, and to transmit one or more control signals indicating an operation of the actuator to one or more of the plurality of motes. 
     According to an exemplary embodiment, a method for indoor localization of a wireless mote network having a plurality of motes is provided. The method includes instructing each of the plurality of motes to sequentially emit a signal and recording by each of the plurality of motes data corresponding to each of the signals observed the mote. The method also includes transmitting the recorded data to a server and generating, by the server, a map of the relative location of the plurality of motes and taking global or local action based on the sensor data. 
     According to a further exemplary embodiment, a computer program product for indoor localization of a wireless mote network having a plurality of motes is provided. The computer program product comprises a computer readable storage medium having computer readable program code embodied therewith. The computer readable program code being configured for instructing each of the plurality of motes to sequentially emit a signal and recording by each of the plurality of motes data corresponding to each of the signals observed the mote. The method also includes transmitting the recorded data to a server and generating, by the server, a map of the relative location of the plurality of motes and taking global or local action based on the sensor data. 
     Additional features are realized through the techniques of the present disclosure. Other systems, methods, apparatus, and/or computer program products according to other embodiments are described in detail herein and are considered a part of the claimed invention. For a better understanding of exemplary embodiments and features, refer to the description and to the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features of the present disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a schematic diagram of a system including a mote network and a controller according to an exemplary embodiment. 
         FIG. 2  is a block diagram of a mote according to an exemplary embodiment. 
         FIG. 3  is a schematic diagram of a wireless sensor network according to an exemplary embodiment. 
         FIG. 4  is a schematic diagram of a wireless sensor network in a hospital according to an exemplary embodiment. 
         FIG. 5  is a flowchart diagram illustrating a method for performing indoor localization of a wireless sensor network in accordance with an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of this disclosure include low-power mote networks, wherein the motes may include a variety of sensors, actuators, power supplies, and processors configured to provide various functionalities. The mote networks may be integrated with existing measurement and management technologies to enhance analytics and information processing capabilities. In exemplary embodiments, the mote network can be used to facilitate data acquisition, processing, and information visualization across a distributed physical environment. 
     Referring now to  FIG. 1 , a system  100  including a mote network  110  and a controller  150  according to an exemplary embodiment is shown. As illustrated, the mote network  110  includes a plurality of motes  112  which are each configured to wirelessly communicate with one or more nearby motes  112 . In exemplary embodiments, the motes  112  may be able to communicate with any other motes  112  within a range of 100 feet. The system also includes a central communications device  120  that is configured to communicate with one or more motes  112  within communication range. In exemplary embodiments, the central communications device  120  may be able to communicate with any motes  112  within a range of 100 feet. The central communications device  120  is also configured to communicate with one or more additional communications systems which may include, but are not limited to, a cellular communications system  122 , a satellite communications system  124 , or a network communications system  126 . 
     Continuing with reference to  FIG. 1 , the system  100  also includes a controller  150  which is configured to communicate with mote network  110  via the central communications device  120 . In exemplary embodiments, the controller  150  may include a server  152 , analytical services  156 , feeders  154  and a client device  158 . In one embodiment, the feeders  154  are configured to receive data from the mote network  110  and provide the data to the server  152 . The feeders  154  may be configured to filter and/or consolidate data received from the motes  112  prior to providing the data to the server  152  or may be configured to provide the raw data to the server  152 . In exemplary embodiments, the server  152  may utilize the analytical services  156  to analyze the data received from the feeders  154 . The client device  158 , which may be a general use computer or other suitable computing device, is configured to communicate with the server  152  and allow a user to access the data received from the motes  112  and to control the operation of the motes  112 . In exemplary embodiments, the server  152  is configured to provide control commands to the motes  112  via the central communications device  120 . 
     In exemplary embodiments, the motes  112  of the mote network  110  are configure to perform indoor localization by combining different localization techniques. These localization techniques may include, but are not limited to, time of flight, received signal strength indicator, and a time synchronization protocol. In exemplary embodiments, based on the device characteristics of the motes  112 , it is possible for mote network  110  to provide indoor device localization with accuracy of two to three feet. In exemplary embodiments, the server  152  is configured to receive location information from each of the motes  112  and to construct a map illustrating the relative locations of the motes  112 . The ability to perform indoor localization is particularly useful in applications that require tracking of people or assets within an indoor space, where other localization systems, such as GPS, do not work. 
     Referring now to  FIG. 2  a block diagram of a mote  200  according to an exemplary embodiment is shown. As illustrated, the mote  200  may include sensors  202 , actuators  204 , interfaces  208 , communications devices  210 , a power supply  212  and a processing unit  206 . In exemplary embodiments, the sensors  202  may be configured to monitor one or more of the following: temperature, humidity, pressure, air flow, CO2 levels, CO levels, presence, noise, corrosion, stress, strain, acceleration, or the like. In exemplary embodiments, the sensors  202  may include transducers that monitor environmental conditions like humidity and temperature and may generate a command that would enable a limitations of the environmental changes due to external factors (using air for cooling, limiting human presence, etc . . .). In addition, other sensors  202  can be used to monitor logistics variables like the location or presence of a person or asset. 
     In exemplary embodiments, the mote  200  may include a wide variety of actuators  204 . The actuators  204  may be configured to control a relay that can be connected to an external system, such as a lighting control system, an air conditioning system, or the like. In exemplary embodiments, the actuators  204  may be latching relays used for simple on-off type of control, while interfaces  208 , such as a serial communication interfaces, can be used for more sophisticated control interfaces with other devices or systems. In exemplary embodiments, the mote  200  may include one or more interfaces  208  to enable the mote  202  to electrically communicate with almost any kind of other device. The interfaces  208  may include, but are not limited to, I2C, SPI, analog I/O, digital I/O, and serial communication RS-232. 
     In exemplary embodiments, the mote  200  includes a processing unit  206  such as a microcontroller. In exemplary embodiments, the microcontrollers of the motes  200  can have different embedded algorithms and the processing units  206  of each mote  200  can carry out different processing tasks. Accordingly, each mote  200  may have processing units  206  with different processing architectures that can be selected based on the requirements of the application performed by the mote  200 . In exemplary embodiments, the mote  200  can support data logging by storing raw or processed data in an on-board memory  214  when required or when wireless network connectivity is not available. The mote is capable of doing self-diagnostic, for example after power-up or power interruption, or self-test and verify its integrity (assets or sensors attached to it or defined in its configuration memory). The mote is also capable of generating alarms in case of self-test failure. 
     In exemplary embodiments, the motes  200  include a communications device  210  that can be used for all the communication and wireless networking done by the mote  200 . The communications device  210  may be a low-power radio that allows the mote  200  to be powered by batteries and have a relatively long lifetime. In exemplary embodiments, to reduce the power consumption of the mote  200 , the communications protocol utilized by the communications device  210  may be based on a time synchronized wireless access. 
     In exemplary embodiments, the motes  200  include a power supply  212 . The power supply  212  may include batteries, a line power adapter, and/or an energy harvesting device. Energy harvesting devices may include solar panel capable of being powered by indoor lighting (or energy harvesting by vibration or radio frequency signals). In exemplary embodiments, the modularity of the motes  200  allows the motes  200  to have different kinds of power supplies  212  in order to be able to adapt to the requirements of the various applications. 
     Referring now to  FIG. 3 , a wireless sensor network  300  according to an exemplary embodiment is shown. As illustrated, the wireless sensor network  300  includes a plurality of motes  310  that are each configured to communicate with other motes  310  or a central communications device  320  within a predetermined range of the mote. In one embodiment, the predetermined range may be approximately  100  feet. In exemplary embodiments, the motes  310  may include a RFID reader configured to sense the presence of one or more RFID tags  312  within proximity  314  of the mote  310 . The RFID reader may be a passive or active reader depending upon the application. In exemplary embodiments, the motes  310  are configured to sense the presence of RFID tags  312  within proximity  314  and to send data regarding the detected RFID tags  312  to a controller  330  via a central communications device  320 . 
     In exemplary embodiments, the mote network may be configured for use in a wide variety of applications. In one embodiment, a mote sensing network can be configured to be used for asset tracking and management. For example, motes can be attached to a server rack and include an RFID reader that can be used to track servers having RFID tags that are placed in the server rack. The tracking of assets in data centers facilitates the location of assets on demand in the space (data center floor, storage room, surrounding office space). In addition, the motes can be configured to detect specific events, such as the movement of an asset (entering or exiting the data center, installing or removing an asset from a rack or re-locating it within a rack). The motes may also actuate door opening based on the sensed signal; block the door if the person is not authorized to remove the equipment, generate an audible warning or notify the appropriate personnel. 
     In another embodiment, a mote network may be configured to improve the preservation of art by monitoring, modeling and managing micro-climatic conditions in the proximity of the art. For example, the mote network may be configured to provide real-time regarding the atmospheric conditions near the art to a server. The server can use that data and operational models which leverage physical analytics to derive micro-climatic conditions in a museum. Such models can supply temperature variations maps, for example, to guide conservators for optimal placement of works of art within the museum space. Sensors attached to the object of art monitoring its state (like a strain sensor attached across one crack of a wood panel that would increase its size due to increased temperature and humidity level generated by human presence) may control the number of people allowed in the exhibition room to maintain a safe condition for the object or art. 
     In yet another embodiment, a mote network may be configured to be used in a hospital to monitor hand-washing compliance by staff.  FIG. 4  is an illustration of a section of the floor plan of a hospital  400  showing two rooms  402  and a corridor  404 . In exemplary embodiments, the hospital  400  can include a mote in each hand sanitizer, for example in  FIG. 4  a first mote  410  disposed in the corridor  404 , a second mote  414  disposed near a sink in each room  402 , a third mote  412  disposed near the entrance to each room  402  and a fourth mote  416  disposed near the outdoor-facing wall in each room  402 . The first mote  410  may include an RFID reader that is configured to monitor the movement of people and assets, such as capital equipment, through the hospital. The third mote  412  may also include an RFID reader that is configured to identify people entering a room  402 . The second mote  414  and the fourth mote  416  are configured to monitor the use of hand washing/sanitizing stations (all motes monitor the usage of the sanitizers and the people who used them, if they are carrying an RFID badge). In exemplary embodiments, the hospital  400  may include a communications device  420  that is configured to communicate with each of the motes (via multihop communication, i.e. not directly from  420  to each mote) and with a hospital server (not shown). The communications device  420  collects the data received from each of the motes and provides that data to the hospital server which can analyze the data to monitor the hospital staff&#39;s compliance with hand-washing protocols. In case of multiple noncompliance events, a visual or an audio warning may be activated to highlight the risk of noncompliance on the patients. Additionally the patients may be also warned about the noncompliance. 
     In exemplary embodiments, the motes may also be used to track the location of supply or capital equipment in the hospital for loss prevention measures. Many of the supply are stored in supply room but is common that healthcare providers will store them locally in various rooms. In case a supply run out in the stockroom, the RFID tagged boxes can be localized in the hospital and provide information to personnel about location and quantity. 
     Referring now to  FIG. 5 , a flowchart diagram illustrating a method  500  for performing indoor localization of a wireless sensor network in accordance with an exemplary embodiment is shown. The method  500  includes deploying a plurality of wireless motes, each mote having a synchronous clock, in an indoor setting, as illustrated at block  502 . In exemplary embodiments, one or more of the plurality of wireless motes may be an anchor mote, which is a mote that has a known location. As illustrated at block  504 , the method  500  includes sequentially emitting a signal from each of the plurality of wireless motes. In exemplary embodiments, the emitted signal may include an identification number for the mote emitting the signal and a time stamp indicating the time the signal was sent. As illustrated at block  506 , the method  500  includes recording by each of the plurality of motes the signals observed by the mote. The motes transmit the recorded data to a central server, as shown at block  508 . In exemplary embodiments, the motes may communicate with the central server through a central communications device. In addition, the motes may communicate with the central communications device through one or more motes in a multi-hop network using a time synchronization protocol. As illustrated at block  510 , the method  500  includes generating a map of the relative location of the plurality of motes based on the recorded data. In exemplary embodiments, the central server may generate the map based on the known location of one or more anchor motes and one or more localization techniques such as time of flight or received signal strength indicator. In exemplary embodiments, based on the device characteristics of the motes, it is possible for map illustrating the relative location of the motes in the mote network to have an accuracy of two to three feet. 
     As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system, method or computer program product. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.” Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium(s) having computer readable program code embodied thereon. 
     Any combination of one or more computer readable medium(s) may be utilized. The computer readable medium may be a computer readable storage medium. A computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. 
     Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing. 
     Computer program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the “C” or other high level programming language or other similar programming languages. The program code may execute entirely on the user&#39;s computer, partly on the user&#39;s computer, as a stand-alone software package, partly on the user&#39;s computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user&#39;s computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). 
     Aspects of the present invention are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     These computer program instructions may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks. 
     The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one ore more other features, integers, steps, operations, element components, and/or groups thereof. 
     The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated 
     The flow diagrams depicted herein are just one example. There may be many variations to this diagram or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order or steps may be added, deleted or modified. All of these variations are considered a part of the claimed invention. 
     While the exemplary embodiments of the invention have been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.