Method and system for constructing a graph representing a building

{
  "publication_number": "US9881397B2",
  "country": "US",
  "kind": "B2",
  "title": "Method and system for constructing a graph representing a building",
  "abstract": "One inventive aspect relates to a method of constructing a graph representing a building (BAT) in which a person (U) moves. In one inventive aspect, the method is adapted to receiving information about the movement of the person in the building over a period of time, the information being collected and transmitted by a portable device (D) associated with the person (U), and in constructing at least one branch of the graph from received movement information. One inventive aspect also provides a method of remotely tracking the activity of a person in a building as a function of the constructed graph. One inventive aspect also provides a server (S) implementing the method of constructing a graph.",
  "claims": [
    "1. A graph construction method for constructing, with a processor, a graph representing a building in which a person moves, the method comprising: receiving, by a remote tracking server over a communications network, a first signal representative of time-stamped information from one or more motion-deriving sensors of a portable device associated with the person, the information relating to the movement of the person over a first period of time in the building, the information being collected from the one or more motion-deriving sensors and being wirelessly transmitted by the portable device over the communications network to the server; in response to the received first signal, determining, by the server, a plurality of path segments from received movement information received from only the one or more motion-deriving sensors, each path segment being identified by a starting position, an ending position, and a movement direction in an arbitrary reference frame, each path segment corresponding to a movement made in a single direction during a time interval, the ending position of each path segment being defined relative to the starting position of that segment, the starting position being the end position of a preceding segment, the starting position for a first segment of the plurality of segments being defined arbitrarily; determining, by the server, a plurality of groups of path segments as a function of positions and of movement direction of the determined path segments; constructing, by the server, at least one branch of the graph from the determined plurality of groups of path segments and from movements of the person; allocating, by the server, a room identifier identifying a room of the building to the at least one branch as a function of the received time stamped movement information and at least one predetermined usage rule associated with determined time ranges; calculating at least one reference value representative of an activity of the person for the room identifier and for a time interval associated with the room identifier; receiving, by the server, time stamped movement information collected over a second period of time subsequent to the first period of time; calculating at least one current value representative of an activity of the person during at least one time interval included in the second period of time; comparing the at least one current value with the at least one reference value; triggering, by the server, an alert process if the difference between the compared values is greater than a predetermined threshold; determining changes in movements of the person over time based on the constructed at least one branch; and based on the determination, transmitting to a user over the communications network a signal regarding the determined changes.",
    "2. The graph construction method according to claim 1, further comprising allocating the room identifier as a function of a predetermined list of rooms and at least one predefined usage rule relating to the rooms.",
    "3. The graph construction method according to claim 2, wherein the allocation of a room name is also a function of a measurement performed by a sensor in the building and/or of an event that is detected in the electrical circuit of the building.",
    "4. The graph construction method according to claim 2, further comprising receiving further information relating to the movement of the person, and wherein the constructing and allocating are reiterated as a function of the further information.",
    "5. The graph construction method according to claim 1, wherein constructing at least one branch comprises: determining a path followed by the person during the movements as a function of received movement information; and determining at least one path segment corresponding to a geographical zone.",
    "6. The graph construction method according to claim 1, wherein the collected movement information comprises angular velocity, acceleration, and magnetic field.",
    "7. The graph construction method according to claim 1, wherein the movement information is collected relative to three axes in a three-dimensional reference frame.",
    "8. The graph construction method according to claim 1, wherein the movement information is collected by an inertial navigation module of the portable device.",
    "9. The graph construction method according to claim 1, wherein the portable device is a cell phone fitted with an inertial navigation module.",
    "10. The method of claim 1, further comprising: processing the movement information to determine a pattern of movement; and triggering the alert process based on a deviation of the movement from the determined pattern.",
    "11. The method of claim 1, further comprising: grouping the path segments together as a function of positions of the path segments and as a function of directions of the path segments, wherein each group of the plurality of groups comprises path segments having positions that are similar and in a same direction.",
    "12. The method of claim 1, wherein each group of path segments of the plurality of groups comprises segments having starting and ending positions situated on the same axis and disposed in same direction.",
    "13. A remote tracking server, the server comprising; a receiver component configured to receive over a communications network a first signal that is representative of time-stamped information from one or more motion-deriving sensors of a portable device associated with a person, the information relating to the movement of the person over a first period of time in a building, the information being collected from the one or more motion-deriving sensors and being wirelessly transmitted by the portable device over the communications network to the server; and a constructor component configured to: in response to the received first signal, determine a plurality of path segments from received movement information received from only the one or more motion-deriving sensors, each path segment being identified by a starting position, an ending position, and a movement direction in an arbitrary reference frame, each path segment corresponding to a movement made in a single direction during a time interval, the ending position of each path segment being defined relative to the starting position of that segment, the starting position being the end position of a preceding segment, the starting position for a first segment of the plurality of segments being defined arbitrarily; determine; by the server, a plurality of groups of path segments as a function of positions and of movement direction of the determined path segments; and construct at least one branch of a graph representing the building on the basis of the determined plurality of groups of path segments and from movements of the person; allocate, by the server, a room identifier identifying a room of the building to the at least one branch as a function of the received time stamped movement information and at least one predetermined usage rule associated with determined time ranges; calculate at least one reference value representative of an activity of the person for the room identifier and for a time interval associated with the room identifier; receive, by the server, time stamped movement information collected over a second period of time subsequent to the first period of time; calculate at least one current valent representative of an activity of the person during at least one time interval included in a second period of time; compare the at least one current value with the at least one reference value; trigger, by the server, an alert process if the difference between the compared values is greater than a predetermined threshold; determine changes in movements of the person over time based on the constructed at least one branch; and based on the determination, transmit to a user over the communications network a signal regarding the determined changes.",
    "14. A non-transitory computer-readable medium including instructions for implementing the graph construction method according to claim 1 when loaded and executed on a processor."
  ],
  "description_excerpt": "This application is a national stage application under 35 U.S.C. §371, claiming priority to International Application No. PCT/FR2011/053076, having an international filing date of Dec. 20, 2011, which claims priority to French Patent Application No. 1061314, filed on Dec. 28, 2010, each of which is hereby incorporated by reference in its entirety and for all purposes.\n\nThe invention relates to the field of smart homes and more particularly to services for providing assistance to the person on the basis of remotely tracking the activity of such a person, i.e. that person's activity in the home environment.\n\nThe systems that have been developed in this field are mostly designed for tracking people who are considered as being “fragile”, typically elderly people living alone. Such systems set out to determine as soon as possible any abnormal modification to the activity of such a person so as to trigger action of an emergency service, a doctor, or a relative of that person, should that be necessary.\n\nFor example, information concerning time spent in each of the rooms and the movements carried out in the home environment make it possible to detect changes in the behavior of the person. A change such as a lack of movement may for example be considered as being indicative of a problem with moving or of illness.\n\nPresently-known systems for remotely tracking a person at home require a plan of that person's home in digital form.",
  "cpc": [
    "G06T 11/26",
    "G06T 11/206",
    "G09B 29/00",
    "G09B 29/004"
  ],
  "ipc": [
    "G06T 11/20",
    "G09B 29/00"
  ],
  "assignees": [
    "Orange SA"
  ],
  "inventors": [
    "Frederic Evennou",
    "Marc Berenguer"
  ],
  "filing_date": "2011-12-20",
  "publication_date": "2018-01-30",
  "grant_date": "2018-01-30",
  "priority_date": "2010-12-28",
  "application_number": "US-201113976926-A",
  "family_id": "45558752",
  "cited_by_count": 2,
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}