ITMI20082044A1 - DEVICE, EQUIPMENT AND SYSTEM FOR THE LOCALIZATION OF OBJECTS OR PERSONS - Google Patents

Description

`` DEVICE, EQUIPMENT AND SYSTEM FOR LOCATING OBJECTS OR PEOPLE ...

The present invention refers to a device for locating objects or people.

The present invention also relates to an apparatus for locating objects or people, suitable for cooperating with the aforementioned device. The present invention also refers to a system for locating objects or people, comprising said device and said apparatus.

Over the last few years, various localization techniques have been developed that make it possible to determine the position of any object with respect to devices with known positions: the most widespread, in terms of commercial success, is GPS (Global Positioning System) technology.

The GPS system is based on surveys obtained from a network of satellites, and does not offer coverage indoors due to signal attenuation in the presence of obstacles.

In the wake of GPS systems, there are now numerous applications, also based on similar operating principles, but intended for use indoors. All RTLS (Reai Time Locating System) systems are based on radiofrequency and can be divided into three groups, each having operational drawbacks and characteristics that are inadequate to meet different specifications in the area of localization:

- RFID active tags that allow to detect the mere presence of objects or people inside the working field of a fixed antenna, but not to locate them in space unless multiplying the number of antennas.

- radiofrequency systems based on the power of the transmitted and received signal, in which accuracy has a strong dependence on the obstacles placed between the transmitter and the receiver, in particular metal structures and reinforced concrete walls.

- radiofrequency systems based on the propagation time of radio waves (UWB - Ultra Wide Band systems): these are very expensive and delicate systems, in which more than one receiver is required in each environment, and each receiver must be wired and synchronized to allow the software to calculate the time difference of reception of the impulse transmitted by the mobile source. These systems are particularly sensitive to the interposition of the human body between receiver and transmitter.

The aim of the present invention is therefore to make available a device, an apparatus and a localization system that allow to identify the position of a person or object in a precise and reliable manner.

Another object of the invention is to provide a device, an apparatus and a localization system which can identify the position of a person or object by performing quick and simple processing.

Another object of the invention is to make available a device, an equipment and a localization system that are characterized by a simple and economical structure, especially with reference to the portable device associated with the object or person to be located.

Another purpose of the invention is to provide a device, an equipment and a localization system that allow to locate the object or person of interest with reduced energy consumption, especially with reference to the portable device associated with the object or person to locate.

In this way it is also possible to increase the autonomy of the portable device itself.

Another object of the invention is to provide a device, an apparatus and a localization system which minimize the risk of interference and overlaps between the signals relating to the localization of different objects / people.

These and other purposes are substantially achieved by a device, an apparatus and a system for locating objects or people according to what is described in the attached claims.

Further features and advantages will become more apparent from the detailed description of a preferred and non-exclusive embodiment of the invention. This description is provided below with reference to the accompanying figures, also having purely illustrative and therefore non-limiting purposes, in which:

- figure 1 is a block diagram representative of a system according to the invention;

- figure 2 is a detailed block diagram of a part of the system of figure 1.

With reference to the accompanying figures, 1 indicates a system for locating objects or people according to the invention.

System 1 can be advantageously used to locate objects or people in small spaces, such as offices, hypermarkets, hospitals, nursing homes, parks, beaches, etc .; by way of example only, the objects to be located may also include wire-guided vehicles and / or stretchers.

In general, system 1 can be applied where it is necessary to identify the position of objects or people in areas that can have dimensions in the order of a few meters or a few tens of meters.

In the case of larger rooms, advantageous use can be made of a plurality of localization equipment, which will be described below.

The system 1 (Figure 1) first of all comprises a localization device 10.

The location device 10 is able to be associated with a corresponding object or a corresponding person so as to allow its position to be identified.

Preferably, the location device 10 is a portable device, suitable for being moved in a manner substantially integral with the object or person to be located.

Preferably the system 1 comprises a plurality of location devices, each suitably associated with the object / person to be located.

By way of example, in the case of locating people, the device 10 can be mounted on a bracelet, so as not to cause annoyance to the person who has to carry it with them.

The device 10, for example, can also be associated with the neck or a leg of the person to be located.

This solution can be particularly advantageous in the case of children, for whom it may be necessary to locate them in recreational areas, parks, beaches, etc.

For the sake of simplicity, figure 1 in any case shows only one localization device 10; however, the system 1 preferably comprises a plurality of location devices having the same structure and the same operation as the location device 10 which will be described hereinafter.

The location device 10 comprises a first transmission module 11 and a second transmission module 12.

The first transmission module 11 is adapted to send a trigger signal 101 to activate a location apparatus 20; the latter has the task of identifying the position of the object or person to which the device 10 is associated.

The second transmission module 12 is able to send a localization signal 102 to the apparatus 20.

Advantageously, the trigger signal 101 has a higher propagation speed than the localization signal 102.

By way of example, the trigger signal 101 can have a propagation speed of 300000 km / s, while the localization signal 102 can have a speed of about 340 m / s.

Advantageously, the trigger signal 101 is an electrical signal, and its propagation from the device 10 to the equipment 20 occurs by propagation of the relative electric field.

In the preferred embodiment, the trigger signal 101 is an RF (Radio Frequency) signal.

This means that the trigger signal 101 has a frequency preferably between 10OOKHz and 300GHz; by way of example only, a frequency of about 2.4GHz can be considered.

Note that, as will become clearer later, trigger 101 will incorporate information; the waveform of the signal will therefore not be perfectly periodic and there will be harmonic contributions at different frequencies.

The trigger signal 101 will therefore be composed of a Radio Frequency carrier, according to the indications provided above, which can be modulated to contain information that will be better described later.

For example, FSK or PSK type modulations can be used; However, the use of other types of modulations is also envisaged.

For example, the trigger signal 101 can be a light signal, a radio wave, an IR (infrared) signal, etc.

The first transmission module 11 can comprise for example a so-called â € œ strip antennaâ € for the transmission of the trigger signal 101. It should however be noted that the transmission module 11 can also comprise antennas of different types.

As mentioned above, the localization signal 102 preferably has a much lower propagation speed than the trigger signal 101.

Preferably, the localization signal 102 is defined by the propagation, in the air, of a mechanical wave.

The locating signal 102 is in particular an ultrasonic signal. This means that the locating signal 102 may have a frequency slightly higher than the frequency of the signals audible to the human ear.

By way of example, the localization signal 102 may have a frequency between 20KHz and 500KHz.

The second transmission module 12 can therefore comprise an ultrasonic transmitter.

In the light of the above, it is clear that the trigger signal 101 propagates with a much greater speed than the localization signal 102.In fact, while the trigger signal 101 has a propagation defined by the propagation of an electromagnetic field (therefore with speed close to the speed of light), the localization signal 102 propagates mechanically in the air and necessarily has a propagation speed of several orders of magnitude lower than the propagation speed of the trigger signal 101.

As mentioned above, the trigger signal 101 can contain information, such as an identification code univocally associated with the person or object whose position is to be determined. This identification code is advantageous if the system 1 must be set up for the location of several objects or people.

In fact, as will become clearer in the continuation of the discussion, in system 1 it is envisaged that a single device 20 is responsible for determining the position of several objects or people, and therefore of several localization devices. Therefore, to allow this equipment to distinguish the various location devices associated with it, it is necessary that they are uniquely recognizable; this purpose is achieved by means of the aforementioned identification code.

The localization signal 102 can instead be constituted by a pulse of determined duration, at the frequency specified above.

Optionally, the location signal 102 can comprise a plurality of such pulses; in the preferred embodiment, however, this signal 102 is not subject to particular modulations or processing, since the "location apparatus 20 only needs to receive the signal 102 itself in order to determine the position of the device 10, and it is not It is therefore required that the localization signal 102 have a further information content.

By way of example only, the duration of each of the pulses forming part of the localization signal 102 can be comprised between 1ps and 10 ms, and for example equal to about 0.4 ms.

Advantageously, the location device 10 further comprises a processing module 13, operatively associated with the first and second transmission modules 11, 12.

The locating device 10 is adapted to cause substantially simultaneous transmission of the trigger signal 101 and the locating signal 102.

In this way, the equipment 20 has the possibility to be activated and to determine the position of the tracking device 10.

Preferably, the trigger signal 101 is transmitted on a predetermined channel, and in particular on a predetermined RF channel.

The RF channel is determined based on the RF band being used.

The location device 10 is therefore conveniently provided with a verification module 14 suitable for verifying that, when necessary, this predetermined channel is â € œfreeâ €, that is, it is available for transmission.

Following this verification, if the outcome is positive, the verification module 14 sends a consent signal 100 to the processing unit 13, so that the processing unit 13 itself can provide generation of the trigger signal 101 and the locating signal 102.

Preferably, the location device 10 further comprises a motion sensor 15, adapted to determine whether the location device 10 itself is moving in a reference system in which the ground is considered stationary. The motion sensor 15 may comprise, for example, one or more accelerometers, or other detection devices capable of discriminating motion conditions from a static condition of the location device 10.

Upon detection of a movement of the device 10, the movement sensor 15 generates an activation signal 99, intended for the processing module 13; the latter then controls the generation of the trigger signal 101 and the localization signal 102.

In this way, it is possible to reduce the energy consumption of the device 10, since no information is transmitted (that is, signals 101 and 102 are not generated) when it is not necessary, that is, when the device 10 is substantially stationary. .

In fact, in order to remain bound to the object or person to be located, the device 10 is provided with an autonomous power supply unit (not shown), for example consisting of a battery.

By avoiding transmitting the signals 101 and 102 when the device 10 is substantially stationary, the useful life of this power supply unit is advantageously increased.

Therefore, in order to be able to control the generation of the trigger 101 and localization signals 102, the processing module 13 must receive first the activation signal 99, and then the consent signal 100.

Once the movement of the device 10 and the availability of the predetermined channel mentioned above have been determined, the processing module 13 will be able to cause the signals 101 and 102 to be generated and transmitted; this transmission can preferably be of a periodic type. For example, every 4 seconds, a trigger signal 101 can be transmitted together with a locate signal 102.

The location apparatus 20 to which we have mentioned above will now be described in greater detail, also forming part of the system 1 according to the invention.

The apparatus 20 (Figure 1) comprises a first receiving module 21, adapted to receive the trigger signal 101, and a second receiving module 22, adapted to receive the localization signal 102.

In practice, the first receiving module 21 can comprise an antenna suitable for receiving RF signals.

The second receiving module 22 can comprise at least two sensors 25 (Figure 2), adapted to separately receive the localization signal 102; in this way, according to the temporal distance with which the same signal is received by the two sensors 25, it is possible to determine the position of the localization device 10.

In the preferred embodiment, the receiving module 22 comprises four sensors 25, arranged for example at the vertices of a substantially square structure.

Preferably, each sensor 25 is provided with a plurality of detectors 26 suitably oriented so as to cover the entire 360 ° angle from which the signals can come.

In practice, by way of example, if the apparatus 20 is used in a closed environment (for example a room), it is mounted in a substantially central position of this closed environment (for example on the ceiling).

Advantageously, the location apparatus 20 further comprises a processing unit 23 operatively associated with the first and second receiving modules 21, 22 to determine the position of the location device 10.

In particular, the processing unit 23 is initially activated by the reception of the trigger signal 101.

In fact, the processing unit 23 can normally be in a stand-by condition.

Following the reception of the trigger signal 101, the processing unit 23 is activated, and at the same time recognizes the location device 10 which generated this trigger signal 101. In fact, as already discussed, the trigger signal 101 embeds in code identifier that allows the device 10 to be uniquely identified among the other devices that can be located by the same location equipment 20.

Therefore, the apparatus 20, and in particular the processing unit 23, prepares itself for the reception and processing of the localization signal 102. Thanks to the presence of more sensors 25, the processing unit 23 can determine the time difference between the instants in which the same localization signal 102 is received by the different sensors and, by means of suitable algorithms, can locate the device 10.

The algorithms used can be, for example, known triangulation algorithms.

In any case, since this technology is of a known type and within the reach of a person skilled in the art, it is not further described here.

Advantageously, also the time difference between the reception of the trigger signal 101 and the reception of the locating signal 102 can be taken into account for determining the position of the locating device 10.

Furthermore, by calculating the position of the device 10 as a function of the difference in the arrival times of the localization signal 102 to the various sensors 25, it allows to compensate for any errors deriving from temperature differences which are reflected in the propagation times.

It is also envisaged that the calculation carried out by the processing unit 23 provides for a compensation of the different characteristics of the sensors 25.

As mentioned above, the trigger signal 101 is transmitted on a predetermined channel, preferably an RF channel. By way of example, this channel can have a frequency of 2.4GHz.

However, it should be noted that the RF channel used can also have a different frequency.

Advantageously, the location apparatus 20 further comprises an operating module 24 adapted to keep the aforementioned predetermined channel occupied between the reception of the trigger signal 101 and the reception of the location signal 102.

In other words, after the location apparatus 20 has received the trigger signal 101, that is when the reception of this signal 101 is substantially completed, the operating module 24 keeps the predetermined channel busy until The reception of the localization signal 102 is also completed, or in any case for a predetermined maximum time.

In this way, it is avoided that other localization devices can insert themselves with their respective trigger and / or localization signals and can therefore lead the processing unit 23 to supply an incorrect output.

In fact, as discussed above, each device 10, before proceeding with the transmission of its own trigger and localization signals, checks (by means of the respective verification module 14) that the predetermined channel is free, that is, it is available for transmission.

The operating module 24 can be set up to keep the preset channel busy for a preset time, starting from the reception of the trigger signal 101. For example, taking into account that the localization signal 102 can travel at about 340m / s, and that assuming that the tracking device 10 is at a distance of less than 15m from the tracking device 20, the preset time can be about 100ms.

It should be noted that the values provided above are entirely exemplary and can be set according to the needs of the specific applications.

Advantageously, the location apparatus 20, in addition to determining the substantially instantaneous position of the various location devices associated with it, stores this position.

It is also envisaged that the apparatus 20 can transmit this position to a remote computer 30, designed to keep track of the various movements undergone or carried out by the people or objects associated with the location devices 10.

The remote processor 30 is therefore able to provide a â € œlogâ € of the positions assumed over time by the devices 10, allowing a tracking activity in the event that it should be necessary to follow or reconstruct the path followed by a specific object or individual.

Advantageously, the processor 30 can also generate an alarm in the event that one or more location devices should leave the coverage area.

It should be noted that, although in figure 1 only one localization device 20 is represented, the system 1 can comprise a plurality of completely similar devices, each dedicated to a specific area in which it is necessary to maintain control of the position of people or objects. .

The various location apparatuses 20 can communicate with each other and with the remote computer 30 via wireless connection, making use for example of the Zigbee protocol; in this way, the only wiring required for mounting the location equipment 20 is related to the power supply.

The invention achieves important advantages.

First of all, the invention allows to individualize the position of a person or object in a precise and reliable way.

Furthermore, the invention makes it possible to identify the position of a person or object by carrying out quick and simple processing.

Another advantage is found in the fact that the various components of the system according to the invention are characterized by a simple and economical structure, especially with reference to the aforementioned location device. Again with reference to the localization device 10, another advantage is related to the reduced energy consumption and its considerable autonomy.

A further advantage emerges considering the fact that the invention allows to minimize the risk of interference and overlapping between the signals relating to the localization of different objects / people.

Another advantage of the invention consists in the fact that the antennas forming part of the tracking equipment have a modular structure, that is, they can be added, moved, and can conveniently cooperate, so as to track the position of the tracking device 10.

Claims (17)

CLAIMS 1. Device for locating objects or people, comprising: - a first transmission module (11) able to send a trigger signal (101), to activate a location device (20) able to identify a position of an object or person to which said device (10) is associate; - a second transmission module (12) adapted to send a location signal (102) and allow said location equipment (20) to identify said position wherein said trigger signal (101) has a higher propagation speed than said localization signal (102). 2. Device according to claim 1 wherein said trigger signal (101) is an electromagnetic signal, said localization signal (102) being preferably defined by a propagation of a mechanical wave. 3. Device according to claim 1 or 2 wherein said trigger signal (101) is an RF radio frequency signal. 4. Device according to any one of the preceding claims, wherein said localization signal (102) is an ultrasound signal, preferably having a frequency comprised between 20KHz and 500KHz. Device according to any one of the preceding claims in which said trigger signal (101) incorporates an identification code associated with the person or object to be located. 6. Device according to any one of the preceding claims comprising a processing module (13) operatively associated with said first and second transmission modules (11, 12), and adapted to cause a substantially simultaneous transmission of said trigger signal (101) and location signal (102), 7. Device according to any one of the preceding claims in which said trigger signal (101) is transmitted on a predetermined radio frequency channel, and said device (1) comprises a verification module (14), suitable for verifying that said channel is available for a transmission and to generate a corresponding consent signal (100), said processing module (13) being operatively associated with said verification module (14) to receive said consent signal (100) and command a transmission of said trigger signal (101) and localization signal (102) at said reception. 8. Device according to any one of the preceding claims, further comprising a motion sensor (15) adapted to determine whether said device (10) is in motion, and to generate an activation signal (99) in the event that said device (10 ) is in motion, said processing module (13) being adapted to receive said activation signal (99) and to command a transmission of said trigger (101) and localization (102) signals according to the reception of said activation signal (99). 9. Device according to claims 7 and 8, wherein said processing module (13) is adapted to control the transmission of said trigger (101) and localization (102) signals after having received both said activation signal (99), is called the consent signal (100). 10. Apparatus for locating people or objects, comprising: - a first receiving module (21) adapted to receive a trigger signal (101) from a locating device (10) associated with a person or object of which it is to be identified a position, - a second receiving module (22) adapted to receive from said locating device (10) a locating signal (102) wherein said trigger signal (101) has a higher propagation speed than said localization signal (102). 11. Apparatus according to claim 10 wherein said trigger signal (101) is an electromagnetic signal, said localization signal (102) being preferably defined by a propagation of a mechanical wave. 12. Apparatus according to claim 10 or 11 wherein said trigger signal (101) is a radio frequency signal RR Apparatus according to any one of claims 10 to 12 wherein said location signal (102) is an ultrasonic signal. Apparatus according to any one of claims 10 to 13 wherein said trigger signal (101) incorporates an identification code associated with the person or object to be located. 15. Apparatus according to any one of claims 10 to 14 comprising a processing unit (23) operatively associated with said first and second receiving modules (21, 22), and capable of determining a position of the object or person with which said tracking device (10) is associated. 16. Apparatus according to claim 15 wherein said second receiving module (22) comprises at least two sensors (25) adapted to receive said localization signal (102), and said processing unit (23) determines the position of said object or person as a function of a time difference between the instants in which said sensors (25) receive said localization signal (102). 17. Apparatus according to any one of claims 10 to 16 in which said trigger signal (101) is transmitted on a predetermined channel, said apparatus (20) being provided with an operating module (24) adapted to keep said predetermined channel occupied at least between the reception of said trigger signal (101) and the reception of said location signal (102). 1B. Localization system for people or objects comprising: - at least one location device (10) according to any one of claims 1 to 9; - at least one location apparatus (20) according to any one of claims 10 to 17,