EP1305777A1

EP1305777A1 - People counter

Info

Publication number: EP1305777A1
Application number: EP01971816A
Authority: EP
Inventors: Hans-Theo Wienand
Original assignee: Wienand Hans-Theo
Current assignee: NICO INTERNATIONAL AS
Priority date: 2000-07-28
Filing date: 2001-07-30
Publication date: 2003-05-02
Also published as: AU2001291702A1; US20030179127A1; DE10037099A1; WO2002011075A1

Abstract

The invention relates to a device for counting at least one person (7) that passes a passage having a floor. Said device comprises at least one distance sensor (3, 4) that emits a cone or rays (5, 6) from radar rays or ultrasonic waves, receives the reflected rays/waves and provides an evaluation device with the received signals. Said cone(s) of radiation (5, 6) cover(s) the entire width of the passage and is/are disposed at an angle with respect to the direction of movement of the person (7) passing the passage. The aim of the invention is to improve people counters known from the art where the distance sensors are often disposed above head height and to provide a counter which is simple in design and which can be disposed as inconspicuously as possible and without being noticed by the people passing the passage. To this end, the distance sensor (3, 4) is accommodated in a housing (1, 2) disposed on the floor.

Description

Personenzählvorrichtung

description

The invention relates to a device for counting people who pass through a floor with at least one distance measuring sensor which emits radar or ultrasound beams in the form of a radiation cone, which receives beams reflected by a person and the signals received by an evaluation device supplies, the or the radiation cone cover the entire width of the passage and are oriented obliquely to the direction of movement of the people passing through the passage.

People counting devices are known in different designs. Light barriers, step mats, door contacts or turnstiles are most often used for this purpose. These devices only fulfill the stated purpose incompletely. Photoelectric sensors have a large error rate because they cannot distinguish between people, animals and objects. Foot mats and door contacts are also very unreliable because they cannot distinguish the direction of movement of the people to be counted. These devices are unusable for wider passages. Turnstiles are perceived as obstacles.

In public buildings such as town halls, schools, theaters, ballrooms, museums, sports stadiums, department stores and the like, as well as on means of transport such as ships, airplanes and the like, the reliable detection of people for statistical and security reasons is of great importance. Furthermore, the heating, ventilation and / or air conditioning can be controlled with the help of the determined number of people, or overfilling can be avoided for safety reasons. For an accurate counting result, counting devices with distance used measuring sensors that work according to the radar principle, the distance measuring sensors having an antenna, which preferably electromagnetic waves, for. B. microwaves or infrared light. The signal reflected by a person or object is picked up by the same or different antennas and passed on to the evaluation device. The evaluation device analyzes the signal and determines the distance between the time a signal is sent and received. The direction and speed of movement of the measured object can also be determined via the change in the distance which results in a change in the intensity of the received signal or via a frequency shift due to the Doppler effect. In such counting systems, the distance measuring sensor is usually arranged above the heads of the people passing through the passage. Examples include the documents US-A-4, 111, 419, DE-A-33 01 763, US-A-4, 528,679, US-A-5, 138,638, US-A-5, 187,688. In the aforementioned documents, the sensors are generally mounted exactly above the passage to count the people passing through a passage, the radiation cones running vertically downward.

The applicant's European patent application EP-0 718 806 A2 discloses such a device in which the radiation cones are oriented obliquely to the direction of movement at an angle of 20 to 25 ° to the vertical. Through this inclination, each of the sensors can determine the direction of movement due to the change in distance when a person moves through the passage, so that the information can be obtained via the evaluation device as to whether a person is in or out of this area through the passage moved out.

A similar device can also be found in document US-A-3,997,866. Here the sensor is either arranged overhead (Fig. 1), or a sensor designed as an antenna with a funnel is attached to a step (Fig. 3) of a vehicle entrance. In particular, the sensor, which forms a projection and is fastened in the stairway area, is readily perceptible to those entering the vehicle. If you step in front of this sensor, it can be damaged or destroyed. The object of the invention is to further develop a people counting device such that it can be arranged as inconspicuously as possible with a simple design and unnoticed by the people passing through the passage.

This object is achieved according to the invention in that at least one distance measuring sensor is arranged in a preferably flat housing arranged on the floor.

The solution to this problem is made possible in particular by the use of a directional antenna for microwave beams, which forms the distance measuring sensor. According to the principle of a patch array antenna, which has a large number of centrally fed individual antennas, so-called patch resonators, on a flat carrier plate, a particularly flat sensor is constructed that enables installation in a housing with a thickness of only 10 mm. An inclination of the radiation field of the antenna, here called radiation cone, is achieved by feeding the different patch resonators with signals of different amplitudes and different phase positions. The construction of patch array antennas with asymmetrical radiation characteristics is known, for example, from communication technology and is described in the book "Broadband Patch Antennas" by Zürcher at al. , ISBN 0- 89006-777-5, pp. 152 to 159. The patch resonators are mounted on a circuit board, so that the antenna itself is only a few millimeters high.

The width of the housing can be well below 100 mm. A practically used design has a width, i.e. an extension in the longitudinal direction of the passage, of 70 mm. The width of the housing for the new patch array antenna can be less than 50 mm.

However, it is also possible to use flat patch antennas with a symmetrical radiation characteristic, ie with a radiation field which runs symmetrically to the surface normal on the carrier plate of the antenna and which are inclined to achieve the inclination of the radiation cone. With conventional sizes of the patch array antennas used here with a range for distance measurement of less than 5 meters, usually 1 to 2 meters, the length of the circuit board carrying the patch resonators is approximately 70 mm. If the antenna is tilted by about 10 ° around its transverse axis The distance between the planes in which the front and rear transverse edges of the antenna lie is less than 12.5 mm. It is therefore possible to install inclined patch array antennas with symmetrical radiation characteristics in flat housings that are less than 20 mm thick.

The integration of the distance measuring sensor for the person counting device according to the invention in such a flat and small housing offers the possibility of integrating the sensor into already existing structures without it being visible from the outside. When monitoring department stores, for example, the integration of the sensor into the antennas of an anti-theft system attached to the floor is a good option. Anti-theft systems generally record signals from passive data carriers that are attached to the goods on display in the department store to protect against theft. Such data carriers are fixed, but releasably attached to the goods by the sales personnel. Magnetic strips that can be detected by the antennas of the anti-theft systems are also attached to the goods. In modern department stores, therefore, a plastic housing is usually attached to both sides of a passage on one or more support rods, in which the antennas of anti-theft systems are installed. When people with secured goods pass through these security antennas, an alarm signal is issued.

Due to the limited range of the antennas of the security systems, the usual widths of the passages between two security antennas are about 1 to 2.5 m. This passage width is ideal for the use of the patch array antennas described, which due to their design and the relatively weak electromagnetic signals also have a limited range.

The flat housings of the goods security systems, which have surfaces extending in the longitudinal direction of the passage, ie parallel to the movement of the people passing through them, can also accommodate the distance measuring sensors of the people counting device according to the invention. The sensors are not visible to people passing through. Furthermore, the mounting of the sensors in these housings is much easier than the mounting above the passage, which in the Usually associated with special structural measures and with the attachment of additional power lines and signal lines. If the housings of the anti-theft antennas are also used, the necessary power supply is usually already available. Data and signal lines of the anti-theft system can either be used or relocated with little effort due to the proximity of the sensors for the people counting device.

In contrast to light barriers, which are already widely used today in conjunction with anti-theft systems for counting people, the device according to the invention with distance measuring sensors, in particular radar sensors, has significant advantages. On the one hand, the direction of movement of a person passing through cannot usually be determined with the light barrier. To do this, a second light barrier would have to be installed just behind a first light barrier. On the other hand, the counting process is disturbed if a person stops in the passage. When using the distance measuring sensors according to the invention on both sides of the passage, the functionality of the second sensor is still given if the first sensor is covered by a person who is standing still. Due to the inclination of the radiation cone of the sensors to the direction of movement, the detection of the direction of movement of a person is possible by evaluating the signal of a single distance measuring sensor of the device according to the invention.

The radiation cones of both sensors extend essentially symmetrically to a vertical plane from the edge of the passage towards the center thereof. The inclination of each radiation cone to the transverse direction of the passage is preferably 10 to 20 °.

As mentioned, the width of the passage between the two housings of the anti-theft systems should be in the range of 1 to 2.5 m. Of course, several such passageways can be arranged side by side to achieve a wider input or output, each of which has its own article surveillance system and thus also has two lateral distance sensors in the housings of the article surveillance antennas of the sensor system according to the invention. All distance measuring sensors of the side by side Passages are connected via data or signal lines to the same evaluation device, which evaluates the signals from the sensors and determines the number of people passing through the passage. In particular, the signals of the sensors arranged on the opposite sides of a passage, whose radiation cones are directed towards one another and towards the center of the passage, are compared with one another by the evaluation device in order to avoid double counting of a person who generates a sensor signal on both lateral sensors , All distance measuring sensors of a monitored building or of a monitored, blocked off area are preferably connected to the same evaluation device, which determines the total number of people within the building or area by analyzing all signals. It is suitable for the signal evaluation of a conventional personal computer, with analog-digital converters converting the signals from the distance measuring sensors (patch array antennas) into digital signals, which are evaluated by evaluation software on the computer. Since modern personal computers are extremely powerful, the personal computer used as an evaluation unit can simultaneously be used for other functions in building monitoring and security, e.g. B. for digital storage of image sequences from surveillance cameras, for control and monitoring of the anti-theft system. In retail stores, the computer can still be used for general data traffic (control of the individual cash register terminals of a central cash register computer, etc.).

As an alternative to the lateral arrangement of the sensor housing, the flat housing can be placed on the floor, the radiation cone extending essentially upwards. Since the housing is preferably less than 10 mm high, inclined surfaces which run in the transverse direction of the passage and form a beveled transition to the plane of the floor can be sufficient to avoid the risk that the people passing through the passage over the transverse housing stumble. Alternatively, a transversely extending recess can be provided in the passage, into which the housing is inserted, so that its surface is flush with the plane of the bottom.

The upward-radiating distance measuring sensors detect a signal as soon as a person walks over them. Through digital signal processing tion and the comparison of the signals generated by the people passing through the passage with signals generated by animals or shopping trolleys, for example, a very reliable detection of the people passing through the passage can take place. Again, the radiation cone is inclined in the direction of movement, ie it has an angle of preferably 10 to 20 ° to the vertical plane running in the transverse direction of the passage.

Such a device can be attached to any location without great effort, for example in the entrance areas to sports stadiums, concert halls or open-air event venues. A plurality of distance measuring sensors are preferably arranged in elongated flat housings which extend over a certain width, for example 1 or 2 m.

To monitor particularly wide passages, the flat housings can have connecting elements at their ends, which can be positively connected to one another. Several flat housings, each with several measuring sensors, can be arranged next to one another and firmly connected to one another in order to monitor the entire width of a passage.

Plastic is particularly suitable for the production of the flat housing, since this does not interfere with the reception when using radar.

As already mentioned, patch array antennas are preferably used as distance measuring sensors. These antennas can either be provided with transmit antenna elements and receive antenna elements or, at the same time, receive a superimposed received signal when transmitting the radar signal, which signal is separated from the transmit signal by a suitable electrical circuit.

The frequency range that is usually reserved for such applications is 24, 125 GHz, i.e. in the micro wave range. The antennas must be designed on this frequency band.

It is expressly pointed out that the invention also includes a combination of at least one housing arranged on one side of the passage and a housing placed on the floor, each of which has at least one distance measuring sensor, in particular a patch array antenna described above.

As an alternative to the above-mentioned exemplary embodiments or in addition to at least one of the above-mentioned exemplary embodiments, the invention also provides for the housing to be arranged with at least one distance measuring sensor in a ceiling of the passage, that is to say above the heads of the people who pass through the passage. This housing and the at least one distance measuring sensor preferably have at least one of the technical features described above.

Preferred embodiments of the invention are set out below

Described with reference to the accompanying drawings. The drawings show in:

Fig. 1 is a front view of a passage with a first embodiment of the counting sensor according to the invention and

2 is a plan view of the passage from FIG. 1,

3 shows a front view of a second embodiment of the counting device according to the invention and

4 shows a side view of the counting device from FIG. 3,

Fig. 5 is a perspective view of a housing for a

3 and 4, FIG. 6 shows a plan view of a variant of the housing from FIG. 5 with form-fitting connecting elements at the ends,

Fig. 7 is a plan view of a patch array antenna, which as

Distance measuring sensor is used in the device according to the invention, Fig. 8 is a front view of the antenna of Fig. 7 and

FIG. 9 shows a side view of the antenna from FIG. 7.

1 and 2, a usual passage for a department store is shown, on the sides of which two flat antenna housings 1 and 2 made of plastic for receiving the antennas of the security or anti-theft systems (not shown) are located. The distance measuring sensors 3 and 4 of the person counting device according to the invention are arranged approximately at waist height. They consist of new types, below described patch array antennas. Its radiation cone 5, 6 extends essentially symmetrically to a horizontal plane. The radiation cone 5, 6 of each sensor 3, 4 is inclined by approximately 20 ° to the transverse direction of the passage that runs between the two antenna housings 1, 2 (see FIG. 2).

As soon as a person 7 passes through the passage, the high-frequency electromagnetic waves emitted by the distance measuring sensors 3, 4 are reflected, and the reflected signals are recorded via the distance measuring sensors 3, 4 and passed on to the evaluation device (not shown). The evaluation device determines from the intensity of the reflected signals the distance of the people 7 passing through to the respective distance measuring sensor 3 or 4. Since the radiation cones 5, 6 run obliquely to the direction of movement of the people 7, a continuously increasing or decreasing distance value arises depending on the direction of movement. Each individual measuring sensor 3, 4 is thus suitable for detecting the direction of movement of the person passing through. On the basis of the measured distance value, it can be determined whether two people pass through the passage next to each other or whether both distance measuring sensors 3, 4 detect the signal of a single person 7 passing through the passage.

The signal evaluation is preferably carried out digitally by means of a central computer, interference signals can be effectively identified and filtered out and a reliable count of the people passing through the passage, possibly with a statistical evaluation of the movements of people over a certain period of time. The distance measuring sensors 3, 4 at different passages can be connected to a central evaluation device.

The ranges of both sensors 3, 4 arranged on the side of the passage must overlap one another, so that complete monitoring of the entire passage is ensured.

3 and 4 show a further embodiment of the people counting device according to the invention. Here, the distance measuring sensors 8 are not arranged on the side of the passage, but on the bottom thereof in the transverse direction of the passage. The radiation cones 9 are the distance measuring sensors 8 inclined at an angle of approximately 10 ° to the running direction (see FIG. 4), ie they run symmetrically to a plane which is inclined at an angle of 10 ° to the vertical plane running in the transverse direction of the passage.

A plurality of distance measuring sensors 8 are arranged at regular intervals of about 10 to 50 cm across the width of the passage, the radiation cones 9 of which overlap, so that people passing through in each area of the passage are reliably detected.

FIG. 5 shows an embodiment of a housing 9 for the distance measuring sensors 8 according to the invention, which is placed on the floor. The housing 10 has an essentially trapezoidal cross section, the inclined surfaces being slightly inclined to the mutually parallel surfaces. The height of the housing 10 is approximately 10 mm, so that the housing 10 with the slightly inclined inclined surfaces does not form an obstacle for the people passing through the passage.

6 shows the ends of two alternative housings 10 '. The housing 10 'has a projection 11 at one end and a receptacle 12 at the other end, which can be fitted into one another in a form-fitting manner. In this way, a plurality of housings 10 'can be arranged next to one another and connected to one another if a passage of greater width is to be monitored.

Of course, the distance measuring sensors have to be wired in the housings 10 ', a connecting cable for the power supply and signal transmission coming out. The cables can be provided with plugs and couplings, so that the connections of a plurality of housings 10 'connected via projection 11 and receptacle 12 can be coupled to one another and then connected together to the evaluation device.

FIG. 7 shows a new type of patch array antenna 13, which is preferably used as a distance measuring sensor in the device according to the invention.

The patch resonators 14 of the patch array antenna 13 are arranged in a matrix of four rows and six columns. The resonators 14 in each Columns are fed with a signal of the same intensity and phase position. In the rows, the patch resonators are each supplied with a signal of different amplitude and phase. It follows from this that the radiation cone of the antenna has a symmetrical radiation cone 9 (see FIG. 8) in the direction of the extension of the columns, each with four patch resonators 14, ie in the short transverse direction of the patch array antenna 13. The radiation cone has a large opening angle in order to cover the greatest possible width of the passage in the embodiment from FIGS. 3 to 6. In the direction of the rows, ie in the direction of the long edges of the patch array antenna 13, the radiation cone 9 is asymmetrical, ie it is inclined to the surface normal plane on the surface of the patch array antenna 13.

LIST OF REFERENCE NUMBERS

1 antenna housing

2 antenna housing e

3 distance measuring sensor

4 Distance measuring sensor

5 radiation cones

6 radiation cones

7 person

8 distance measuring sensor

9 radiation cone

10 housing

10 'housing

11 head start

12 recording

13 patch array antenna

14 patch resonator

Claims

Expectations

1. Device for counting at least one person (7) who passes a passage with a floor, with at least one distance measuring sensor (3, 4; 8) that transmits radar or ultrasound beams in the form of a radiation cone (5, 6; 9 ) which receives the rays reflected by the at least one person and feeds the received signals to an evaluation device, the radiation cone (s) (5, 6; 9) covering the entire width of the passage and obliquely to the direction of movement of the person passing through the passage (7 ) are aligned,

characterized,

that the distance measuring sensor (3, 4; 8) is arranged in a flat housing (1, 2; 10, 10 ') arranged on the bottom.

2. Device according to claim 1, characterized in that the device has a plurality of distance measuring sensors (3,4; 8), each of which emits a radiation cone (5,6; 9) from radar or ultrasound beams, which was reflected by the at least one person Receive beams and feed the received signals to an evaluation device, the radiation cones (5, 6; 9) covering the entire width of the passage and being oriented obliquely to the direction of movement of the person (7) passing through the passage, and that a single distance measuring sensor

(3, 4; 8) or more distance measuring sensors is or are arranged in the housing.

3. Apparatus according to claim 1 or 2, characterized in that the housing (1,2; 10, 10 ') is attached to the floor.

4. The device according to at least one of the preceding claims, characterized in that the flat housing (1, 2; 10, 10 ') is less than 50 mm, preferably about 10 mm, thick.

Device according to at least one of the preceding claims, characterized in that on both sides of the passage a flat housing (1, 2) is arranged which, in addition to a distance measuring sensor (3, 4), has a detection sensor of an anti-theft system.

6. The device according to claim 5, characterized in that the two flat housings (1,2) facing each other, extending in the longitudinal direction of the passage surfaces.

7. The device according to claim 5 or 6, characterized in that the radiation cone (5,6) of the distance measuring sensors (3,4) substantially horizontally and at an angle of more than 5 °, preferably 10 ° to 20 °, to the transverse direction of the Are aligned.

8. The device according to at least one of claims 5 to 7, characterized in that the width of the passage between the two flat housings (1, 2) is less than 5 m, preferably 1 to 2.5 m.

9. The device according to at least one of the preceding claims, characterized in that the flat housing (10) is placed on the floor.

10. The device according to claim 9, characterized in that the flat housing (10) is inserted into a recess extending in the transverse direction of the passage in the bottom.

11. The device according to claim 9 or 10, characterized in that the or the radiation cone (9) at an angle of more than 5 °, preferably 10 ° to 20 °, are inclined to a vertical plane extending in the transverse direction of the passage.

12. The device according to at least one of claims 9 to 11, characterized in that the flat housing (10) is elongated and has a plurality of distance sensors at a distance from each other.

13. The device according to at least one of claims 9 to 12, characterized in that a plurality of flat housings (10 ') are arranged side by side over the entire width of the passage, each end section. Section of a flat housing (10 ') has a connecting element (11, 12) which cooperates with an end section of an adjacent flat housing (10') in a form-fitting manner.

H. Device according to at least one of the preceding claims, characterized in that the flat housing (1,2; 10, 10 ') consists of plastic.

15. The device according to at least one of the preceding claims, characterized in that each distance measuring sensor (3,4; 8) is formed by a flat patch array antenna (13) for transmitting and receiving electromagnetic waves.

16. The apparatus according to claim 15, characterized in that the patch array antenna (13) has a plurality of patch resonators (14) which in

Rows are arranged which run in the longitudinal direction of the passage, the successive patch resonators (14) being fed in a row with signals of different amplitudes and phase positions.

17. The apparatus of claim 15 or 16, characterized in that the patch array antenna (13) emits electromagnetic radar beams in the frequency band of about 24 GHz.