SYSTEM AND METHOD FOR DETERMINING A POSITION OF AN OBJECT
FIELD OF THE INVENTION
The invention relates to a system and method for determining the position of an object. The system may be used in amusement parks, in shopping centers, in airports or other areas, where the need for rapid and precise determining of a position of an object is present.
BACKGROUND ART
Amusement parks and other entertainment parks are typically confronted with a large number of logistical challenges in their day-to-day operations. The parks must process admissions, promote services in the parks, and perform crowd control, all while trying to create a hassle free and enjoyable experience for visitors. Parks must also provide for the safety of young children that become separated from their parents and for young teenage children that may be left alone at the park for the day.
In addition to the day-to-day challenges, parks must also continuously adapt their rides and services to follow public trends and keep public interest in the park. Such adaptations include providing popular shows to attract crowds, updating technology to increase the excitement of existing rides and replacing outdated services with newer technologies.
GB 2 360 862 describes a system for monitoring people within an area. The people are carrying a tag within the area and the people can be monitored by remotely reading the tags at a number of interrogating means placed a number of predetermined positions. The position of the interrogating means are known, and when a person gets in a distance between 0,5 - 7 m of the location of such interrogating means the tags is read and hereby the location of the person carrying the tags is known. The interrogating means are connected to a central processing system and/or a number of computers. It is disclosed that if e.g. a child carrying a tag is missing, the parents may find the child by finding and alerting a security staff. The security staff may then locate the child by accessing the central processing system and tell the parents with which interrogating means the tag carried by the child have been read lastly. The system is also used for research purposes e.g. to analyze, which positions is frequented the most and by whom.
This system has the technical drawback that the position of the tag will only be possible to establish when or if the tag changes location towards a position of an interrogating means being able to read the tag. Furthermore, the system has the technical drawback that a
parent having lost a child has to go to a certain place to get help and afterwards find a staff person, who is able to help the parent find the child. This person helping the parent then has to access the central processing system and tell the parent a position of the tag carried by the child. Thereafter, the parent must find the child with the tag at the position being told by the staff person. All these steps may take a long time.
SUMMARY OF THE INVENTION
An object of the invention may be to provide a system, where a user is able to locate an object with a precision within a few meters or even less than one meter from any location. Another object of the invention may also be to provide a system where the position of an object may be found by only one individual - namely the individual (the user) having the need for finding the object, thereby without the necessity of alerting other persons.
Another object of the invention may be to provide a system where the individual will not have directly to access equipment, the operation of which is not known to the individual. A further object of the invention may be to provide a system and a method of determining the position of an object that requires a minimum of pay back time and that requires an absolute minimum of maintenance. The invention will have further objects that will be understood from the following.
According to the above objects of the invention and in accordance with a first aspect of the invention a positioning system is envisaged for a predetermined area, the positioning system comprising - at least one tag attached to the object and capable of transmitting at least one signal within a certain time interval, preferably a frequently transmitted signal,
- at least two antennas situated in the predetermined area at predetermined positions and intended for simultaneously receiving the at least one signal from the at least one tag,
- at least one central server connected to the at least two antennas and provided with means for receiving and processing the signal received by the antennas, wherein
- the central server is provided with a gateway for providing communication from the central server to at least one portable data transmitting and receiving means,
- said communication being provided upon request from said at least one portable data transmitting and receiving means to said central server, and - said central server capable of communicating to the at least one portable data transmitting and receiving means a position of the at least one tag,
- said position being correlated to a mapping of said predetermined area.
The provision of at least two antennas and a central server preferably only providing information of the position of the tag upon request from a person having a need to find the object, reduces the need for constant monitoring and storing of portable data of the position of the tag. Also, the need for constantly informing any person of the position of the tag is dispensed with. Thus, the energy consumption of the system is reduced and the lifetime is increased of the system and of any batteries powering remote units.
Also, the provision of a portable data transmission and receiving means reduces the overall costs of establishing the system, since stationary data transmitting and receiving units may be omitted, apart from the antennas being non-intelligent signal receiving and transmitting means with no information capability to a user being a human being.
The wording "in the predetermined area" in connection with the positions of the antennas may also comprise "in a distance from the predetermined area where receiving the transmitted signal is possible".
According to a second aspect of the invention there is provided a method of determining a position of a possibly moving object in a predetermined area.
In general the aspects of the invention and/or the possible advantages may be combined and coupled in any way possible within the scope of the invention.
These and other aspects, features and/or advantages of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE FIGURES
The invention will hereafter be described with reference to the figures, where
FIG.l is a overview in principle of an embodiment of a system according to the invention FIG.2 shows an example of a map of an amusement park with gridlines FIG.3 shows a position in the amusement park of a tag being displayed to a user, and FIG.4 shows the density of positions of all tags in the amusement park being displayed.
DETAILED DESCRIPTION OF THE INVENTION
The invention may as mentioned be suitable for a number of predetermined areas, but in the present description will be described in particular with reference to amusement parks.
FIG. 1 shows a system according to an embodiment of the invention. A possibly moving object is shown at 1. The possibly moving object is equipped with a tag, in this case a WiFi tag. WiFi is an interoperability certification for wireless local area network (WLAN) products based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. The WiFi tag used in this embodiment of the invention is operating according to the standard 802.11b, an international standard for wireless networking that operates in the 2.4 GHz frequency range (2.4 GHz to 2.4835 GHz) and provides a throughput of up to 11 Mbps. Operating according to other standards and at other frequencies will be possible depending on the application in question and depending on the possible technical possibilities and restraints in a predetermined area where the system is employed.
WiFi tags preferably have unparalleled battery life through the use of a power-saving design, perhaps up to 3 to 5 years of continuous operation. Through the use of a clear- channel assessment mechanism, WiFi tags are able to avoid interference with standard WiFi data communications. WiFi tags can be mounted in many different ways on a variety of objects, including the use of double-sided tape, screws, straps, clips, wristbands, safety pins and specific mounting accessories, and the tag enclosures are water resistant and can survive significant shocks and drops, enabling use in challenging work environments and outdoors.
The WiFi tag in this embodiment of the invention is sending a radio frequency signal pulse each eighth second. A signal being sent with another time interval between the individual signal pulses may be provided. The signal may be received by at least two antennas 2, in the embodiment shown a number of the three antennas. In the embodiment shown, the antennas 2 are NEMA antennas. In other embodiments of the invention, another number of antennas may be chosen.
The three antennas are connected to a switch 3 by cables, but may as well be wirelessly connected (not shown). The switch 3 is connected by cables to a central server 4, but may as well be wirelessly connected, (not shown). The central server 4 is connected to an IP- address on the Internet 5 allowing for connection to a gateway 6 for sending and receiving messages such as SMS (Short Messenger Service) messages. The server may as an alternative or additionally, as a safety precaution, be directly connected to a gateway, i.e. via a private network and not a public network such as the Internet. Such direct connection is not shown in the figure. Via the Internet, a browser 7 may be used to access the central server. Alternatively or additionally, a browser may be connected directly to the central server, not using a public network such as the Internet. This connection is not shown on the figure.
The gateway 6 may receive and transmit messages such as SMS messages to a portable data transmitting and receiving means such as a mobile phone carried by a user (the mobile phone and the user not shown). In the following, a mobile phone will be used as example of a portable data transmitting and receiving means. Other portable data transmitting and receiving means may be portable computers, Personal Digital Assistant (PDA), wireless laptops, barcode readers and other enabled devices within WiFi networks. Also, other kind of messages than SMS messages may be envisaged depending on present and future wireless communication possibilities and depending on the gateway in question.
The user may be present within the predetermined area to be surveyed or the user may be present anywhere else, where a mobile telephone connection to the gateway 6 is available. The word user characterizes the person carrying the mobile phone. In case the possibly moving object is a human being, this human being is not the user, but is the object, the position of which is to be determined by the user.
When, as in the case of the present invention, at least two antennas are used, the central server 4 may use triangulation methods for determining the position of the tag 1 attached to an object (not shown). The position is either determined based on a signal from at least two antennas and a previous position of the tag 1 or on signals received from at least three antennas at the same time. Depending on the size of the predetermined area, which the system has to cover, and depending on the precision to be achieved, a higher number than three antennas may be used.
The central server 4 is provided with means for receiving, storing and processing the signals from the switch 3 and may also be equipped with timer means for collating a time of the day with the received signals and the processed position(s) of the tag.
In the embodiment of the system shown, the browser 7 is provided for showing a map of the entire or of part of the predetermined area. The browser may also be used for research purposes, such as for improving the layout of the predetermined area or monitoring behavior of the person in the predetermined area. In this situation it is assumed that the object holding the tag is a human being, and that this human being is together with the user, i.e. the person carrying the mobile phone.
Improving the layout and/or changing the behavior of the persons in the predetermined area may employ processing and displaying the density of tags in specific places and along specific routes within the predetermined area. This may be achieved by defining the routes and other specific places as predetermined sub-areas of positions. If a position of a tag is
determined as being within this sub-area, the tag is viewed upon as part of the total number of tags in the sub-area.
A high density of tags in a predetermined sub-area may be used by the management of the predetermined area to send messages to users carrying the mobile phone. These messages may lead to the users to remember that another part of the predetermined area, e.g. a special site, is soon showing something spectacular. Hereby the crowd of persons is spread, but also different spectacular events may be announced to all persons in the sub- area. Any action by the management may e.g. also be to offer a certain service to the persons in the sub-area. In the example of the predetermined area being an amusement park, this could e.g. be sending a message to a number of ice cream sales cars to go to the area, where the most persons are present.
Regardless of the density of tags in a predetermined sub-area, the users, such as an elder child or a grown-up in an amusement park, and being present outside e.g. a restaurant (or a specific amusement) in the amusement park may be send a message on their phone. This message could e.g. be the waiting time for a free table or prices for a meal in the restaurant. At the restaurant, there may also be guidelines of how to request these specifications by use of a phone.
FIG. 2 shows a map representing a predetermined area 20 in which a possibly moving object may be surveyed. In or around the predetermined 20 area, a number of antennas (not shown) will be placed. The antennas may e.g. be placed in each interception point of the gridlines in the map of the predetermined area or in the middle of each grid area in the map, or at the alike suitable predetermined positions within the predetermined area.
A map of the area may be handed over to a user at entry into the predetermined area or together with tags being handed over to holders of tags. The map may also be displayed at certain positions in the area or may be displayed upon request on the mobile phone or other portable device.
FIG. 3 shows a way of initially transmitting a request from a mobile phone to the central server 4 and subsequently receiving at the mobile phone a position of the tag from the central server. The central server is described with reference to figure 1. In section 30 of the figure, the message is 'LL Help" and the phone number or SMS address to send this message to at central server is shown in section 31 as '1279'.
The central server, perhaps already having established the position of the tag or perhaps immediately establishing the position of the tag, in response to this request transmits a
message to the mobile phone stating that the tag is positioned in 'section D5' as shown in section 32 of the figure. The position may be given with a further precision down to a few meters or even less than one meter from the actual position of the tag.
In particular, a message may be transmitted automatically to a user surveying an object carrying a tag, if the position of the tag is changing to the outside premises of the predetermined area. This message may also help the management of the predetermined area to collect the tags, when an object is leaving the predetermined area and perhaps has forgotten to hand over the tag to the management or the predetermined area before leaving the predetermined area.
FIG.4 shows a map of the predetermined area. The map shows the density of tags throughout the area. The number of tags on each route is given by different colors of the lines representing the routes. The number of tags within an area or along a route is registered by continuously monitoring the transmission signals between the tags and the antennas. The ratio at which the transmission signals are transmitted from the tags is a known predetermined and possible pre-adjustable ratio, and by counting the number of transmissions signals within correspondingly established time intervals the number of tags in the area or along the route may be established. It may be a further object to establish not only the number of tags but also to establish the duration of time each tag is located in the area or along the route. This may be accomplished by monitoring the transmission ratio of each tag, i.e. the number of times a transmission signal is detected from each tag. In this application a ratio or the ratio may be understood as a rate at which the transmission signals are transmitted from the tags, e.g. at the rate of seven times per minute.
If only a few transmission signals from each tag is monitored in the area or along the route, it is an indication of the tag in question, and thus the object in question, only passing by the sub-area or along the route, but if many objects are passing by at the same time, the number of tags being monitored may still be many, although each tag only is present in the sub-area or along the route during a short period of time. With reference to amusement parks, such areas may be key locations with information sites or toilets, or it may be a junction between two or more different sites of the amusement park.
If however many transmission signals from each tag is monitored in the area or along the route, it is an indication of the tag in question, and thus the object in question, actually remaining in the sub-area or along the route for a prolonged period of time, and the number of tags being monitored will still be many. With reference to amusement parks,
such areas may be key sites with the most favored amusements or it may be locations with restaurants, shops and the like or it may be often used routes between the sites.
The data for generating this map of the predetermined area is the data received and stored about the positions of the tags along with the time and duration at which the tags were present at a certain position or within a certain predetermined sub-area.
The visualization of the number of tags and the period of time during which the tag is situated in the sub-area or along the route may be accomplished in different ways. One way is to use a computerized system with a map of the different sub-areas and/or routes being monitored. Also, it will be possible to display the different sub-areas and/or routes in a table, and listing the time of the day when a certain monitoring took place and the number of tags being present in each sub-area and/or along each route at that time of the day.
The visualization using a map offers the possibility of using colors in order to roughly, however easily, showing the number of tags and the period of time each tag is situated in each sub-area and/or along each route. The visualization using a table offers the possibility of using numbers in order to precisely, however not as easily, showing the number of tags and the period of time each tag is situated in each sub-area and/or along each route.
The routes 40 are showing a high density of tags, the route 41 is showing a low density of tags. These data may be used to change the layout of the predetermined area, i.e. perhaps making more space available on routes 40, or to change the presently chosen routes of the users by sending messages to the users about perhaps choosing other routes less crowded. The data may also be used for other research purposes and possible commercial uses.