Classifications

• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06M—COUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
  • G06M11/00—Counting of objects distributed at random, e.g. on a surface
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06M—COUNTING MECHANISMS; COUNTING OF OBJECTS NOT OTHERWISE PROVIDED FOR
  • G06M1/00—Design features of general application
  • G06M1/08—Design features of general application for actuating the drive
  • G06M1/10—Design features of general application for actuating the drive by electric or magnetic means
  • G06M1/101—Design features of general application for actuating the drive by electric or magnetic means by electro-optical means
• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
  • G07C9/00—Individual registration on entry or exit

Definitions

• the present invention relates to a device making it possible to detect the presence and to determine the direction of passage of mobiles for the purpose of counting.
• the term “mobile” applies as much to an object as to a living being.
• the detection and the determination of the direction of passage of mobiles are usually done using a mechanical infrastructure of the turnstiles or gates type, or optical systems with beam cutting.
• the turnstiles generally have three branches A person crossing the turnstile does turn it a third of a turn This rotation constitutes detection, and an external system can count the number of people who have passed
• This device requires a large and costly ground infrastructure II causes a slowdown in the flow of pedestrians having to pass the turnstile, by a bottleneck effect, and can only operate in a single direction of passage
• Another known device implements an infrared bamer, consisting of a emitting part and a receiving part facing each other and thus forming a line immaterial A pedestrian crossing this line is detected by the non reception of the light beam coming from the director An external system can thus count the number of people crossing the barrier
• Infrared barriers need to be placed at a distance from the ground compatible with the size of the mobiles to be detected
• detecting people requires placing the barrier at a about a meter in height, which requires
• the device according to the invention is fixed to the vertical of the mobiles to be detected (ceiling for example), which does not require any infrastructure on the ground and puts it more to the ab ⁇ of possible acts of vandalism In addition, it comes under in the form of a monobloc, thus not requiring two separate elements, unlike the infrared barrier This arrangement does not generate a slowdown in the flow of the mobile flow
• the device according to a first characteristic, comprises a housing comprising a first share two transmitters (1 and 4) each having the function of emitting a beam towards a mobile by means of optical means, on the other hand a reception system made up of two elements (2 and 3) capturing the beam reflected by the mobile passing through the detection zone by means of a reception optic, and thirdly an electronic control of the emission elements (1 and 4) and of processing of the signals received by the reception elements (2 and 3).
• the first and second transmitters (1 and 4), as well as the reception elements, are infrared diodes.
• the electronics for controlling each transmission element and for processing the signals received by each reception element comprises a clock (17). pulse generator driving each transmission element, an amplifier (18) amplifying the light signals generated by each reception element, and a blocking sampler (19) synchronized with said clock making it possible to block the amplified signals and to compare them at a reference voltage by means of a comparator (20)
• the layout of the transmission and reception systems complies with the following relationships
• the device incorporates two synchronized infrared transmitters and two receivers making it possible to generate two detection zones in space in the direction of movement of the mobiles.
• the existence of these two virtual detection zones makes it possible to determine the direction of passage of the mobiles by direct reflection
• the transmitting elements continuously emit light pulses At rest, when no mobile is present, the receivers receive no signal When a mobile passes through the detection zone of the sensor, this zone being between a minimum distance and a maximum distance, it meets a first beam This beam is reflected on the mobile and is detected by the first receiver By continuing its movement, the mobile then cuts the second beam The second beam is reflected on the mobile and is detected by the second receiver.
• the chronology of the light beams received makes it possible to determine the direction of passage of the mobile
• this figure represents the minimum distances and maximum detection distances
• this figure represents the block diagram of the electronics used for the device
• the device comprises two emitters of the infrared diode type (1 and 4)
• the light emitted by these infrared emitters is focused using an optical emitting device (5 and 7)
• a mobile cutting the beam emitted by the first infrared transmitter (1) reflects this beam
• the reflected beam (10) passes through the reception optics (6) to reach the first reception element (3)
• a signal is then received by the first receiving element (3)
• the mobile continuing its movement cuts the beam emitted by the second infrared emitter (4), and reflects this beam
• the reflected beam (1 1) passes through the reception optics (6) to reach the second reception element (2)
• a signal is then received by the second receiving element (2)
• the signals received on the reception elements (2 and 3) make it possible to know the presence and the direction of passage of the mobile If the first reception element (3) receives a signal before the second reception element (2), the mobile moves in a direction from the first transmitting element (1) to the second transmitting element (4) If the second receiving element (2) receives a signal before the first receiving element (3), the mobile moves in a direction from the second transmitting element (4) to the first transmitting element (1)
• the device according to the invention allows the detection of mobiles cutting the beam emitted by the first transmitter (1) over a zone comp ⁇ se between a minimum distance (12) and a maximum distance (14). It allows the detection of mobiles cutting the beam emitted by the second infrared emitter (4) over a zone comp ⁇ se between a minimum distance (13) and a maximum distance (15).
• the maximum (14) and minimum (12) distances are determined by the focal length (16) of the reception optics (6), the size of the sensitive surface of the first reception element (3), the distance (9) between the first reception element (3) and the axis of the reception optics (6), the distance between the transmission optics (5) and the reception optics (6)
• the maximum distances (15 ) and minimum (13) are determined by the focal length (16) of the reception optics (6), the size of the sensitive surface of the first reception element (2), the distance (8) between the second reception element (2) and the axis of the reception optics (6), the distance between the transmission optics (7) and the reception optics (6)
• the transmission elements (1 and 4) are controlled by pulses supplied by a clock (17).
• the pulsed light signals received by the reception elements (2 and 3) are amplified by means of an amplifier (18). After amplification, the received signals are blocked synchronously with the transmission clock by means of a blocking sampler (19), so that they can be compared with a reference voltage in a comparator (20). The result of this comparison gives the output signal 1 and the output signal 2.
• FIG. 4 represents the timing diagrams of the output signals (output 1 and output 2) for a mobile passing in the direction first transmission element (1) towards second transmission element (2).
• Niche-shaped signals appear when the receiving elements no longer receive a signal.
• FIG. 5 represents the timing diagrams of the output signals (output 1 and output 2) for a mobile passing in the direction from the second transmission element (2) to the first transmission element (1).
• Niche-shaped signals appear when the receiving elements no longer receive a signal.
• the device can be provided with 2 reception optics, each being associated with a reception element (2 and 3)
• the main industrial applications of the device are in particular the detection and determination of the direction of passage of mobiles moving alone or in groups and in various places for counting. For example, it is the counting of people entering and leaving a means of transport for people (metro, bus, train ...) or a public or private place, counting in particular of objects passing on a carpet driving, counting vehicles ...
• Several devices according to the invention can be combined to detect and determine the direction of passage of mobiles moving head-on, for the purpose of counting (in the case of people moving in a metro corridor for example).
• the number of devices to be used depends on the size, shape and type of mobile to be detected.
• the devices used as described above must be synchronized so that there is no optical interference.
• the arrangement of the devices described above allows further processing of the information supplied at the output of the devices.
• the treatments can be as follows:
• redundancy the signals supplied by neighboring devices can be compared to obtain reliable information.
• the signals provided by the devices can be analyzed to detect the presence and determine the direction of passage of mobiles moving along an ill-defined axis (case of pedestrians in a metro corridor for example)

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Theoretical Computer Science (AREA)
• Geophysics And Detection Of Objects (AREA)
• Optical Radar Systems And Details Thereof (AREA)
• Control Of Conveyors (AREA)

Priority Applications (6)

Applications Claiming Priority (2)

Publications (1)

Family

ID=26231218

Family Applications (1)

Country Status (6)

Cited By (5)

Families Citing this family (8)

Citations (9)

• 1994
  • 1994-06-08 FR FR9406962A patent/FR2721126A1/fr active Granted
• 1995
  • 1995-12-14 EP EP95942739A patent/EP0867018B1/fr not_active Expired - Lifetime
  • 1995-12-14 DE DE69525981T patent/DE69525981T2/de not_active Expired - Lifetime
  • 1995-12-14 ES ES95942739T patent/ES2173212T3/es not_active Expired - Lifetime
  • 1995-12-14 WO PCT/FR1995/001473 patent/WO1997022089A1/fr active IP Right Grant
  • 1995-12-14 PT PT95942739T patent/PT867018E/pt unknown

Patent Citations (9)

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