JP2009138375A - Method and system for detecting worker around working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a system for detecting a worker around construction machinery with an arm member, which keep variations in detection distance in an approach direction small. <P>SOLUTION: A directional antenna 14 directed to the side of the arm member 3 together with a nondirectional antenna 17 is mounted on the body section 2 of the working machine 1 with the movable arm member 3 operating on a job site 9; the worker 10 in the job site 9 holds an active RFID tag 11 which transmits an ID signal; and the worker 10 getting closer to the periphery of the working machine 1 is detected by the reception of the ID signal of either the nondirectional antenna 17 or the directional antenna 14. Preferably, the pair of directional antennae 14a and 14b directed to the side of the arm member 3 is mounted on both the sides of the arm member 3 of the body section 2 of the working machine 1, respectively. More preferably, the pair of directional antennae 14a and 14b is mounted on the locations, different in height from each other, of the body section 2 of the working machine 1, respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a worker detection method and system around a work machine, and more particularly to a method and system for detecting the approach between a work machine having a movable arm member such as a boom or an arm and a worker around the work machine.

  Construction and civil engineering work sites (hereinafter sometimes referred to as work sites) that use construction and civil engineering machines (hereinafter sometimes referred to as work machines) such as bulldozers, hydraulic excavators (backhoes), and mobile cranes are improved on-site safety. Therefore, it is important to prevent accidents associated with the work of construction machines, especially to prevent accidents caused by contact between work machines and workers. The work machine is operated while paying sufficient attention to the surroundings by the operator. However, human error (insufficient confirmation of the blind spot worker's safety, etc.) cannot be avoided only by the safety check by the operator's visual check. There are accidents where the machine and the worker come into contact with each other, or the worker is caught between the work machine and the existing structure / equipment.

  Conventionally, in order to support and assist the operator's visual confirmation and prevent human error, for example, as disclosed in Patent Document 1, an infrared sensor, an optical sensor, and the like that detect a distance between a work machine and surrounding workers, There has been proposed a system in which detection means such as an ultrasonic transceiver is attached to a work machine and the work machine is stopped or an alarm is notified to an operator of the work machine according to the detection distance. However, detection means such as infrared sensors, optical sensors, and ultrasonic transmitters / receivers are prone to malfunction due to the influence of the surrounding environment (sunlight, wind, electromagnetic noise, etc.), and they are reliable to support and assist the operator's visual confirmation. There is a problem of lack of sex.

  On the other hand, Patent Documents 2 to 4 propose a system for detecting workers around a work machine using RFID (Radio Frequency IDentification) communication technology that reads an ID signal in a contactless manner by wireless communication. . For example, in Patent Document 4, an active RFID tag (IC tag) including an antenna and an IC circuit is carried by a worker at a work site, and a receiving device with an antenna is mounted on a work machine, and for example, 0.2 second from the RFID tag. Disclosed is an alarm device that intermittently emits an ID signal at intervals and notifies an operator of the work machine of an alarm corresponding to the ID signal received by the receiving device (an alarm of a different color or sound depending on the ID signal). . According to a system using an active RFID tag equipped with a battery, communication of an ID signal of about 5 to 20 m, which is a work range of a work machine, is possible, and a unique ID signal is detected for each tag. Since the influence of the surrounding environment can be suppressed to a small level, it can be expected that the reliability of detection of workers approaching the work machine is improved compared to a system using an infrared sensor, an optical sensor, an ultrasonic transceiver, etc. .

JP 09-099807 A JP 2003-168174 A JP 2005-346228 A JP 2007-120110 A

  However, when a conventional worker detection system using an RFID tag is applied to a work machine having a movable arm member such as a boom or an arm, the detection distance of the worker varies depending on the direction approaching the work machine. There is. For example, when applied to a working machine 1 having a movable arm member 3 in the front as shown in FIG. 1 (backhoe in the illustrated example), it is difficult to attach a receiving antenna to the movable arm member 3 that vibrates and swings. A receiving antenna must be attached to the main body 2 (including the driver's seat 4) that supports the movable arm member 3. In the worker detection systems of Patent Documents 2 to 4, it is assumed that workers in all directions around the work machine 1 are detected by a single or a plurality of receiving antennas attached to the main body 2 of the work machine 1. However, according to the experiment of the present inventor, when the metal movable arm member 3 exists between the worker (RFID tag) approaching from the front of the work machine 1 and the receiving antenna on the main body 2, The detection distance is reduced due to the influence of radio wave reflection of the movable arm member 3.

  9A shows a single omnidirectional antenna on the front side (arm member side) A and the rear side (opposite side of the arm member) G of the main body 2 of the work machine 1 with the movable arm member 3 shown in FIG. , And the worker 10 carrying the RFID tag set at a communication distance of 7.5 m is made to approach the center of the work machine 1 in the radial direction from a distance, and the two omnidirectionalities of the front side A and the rear side G The result (radar chart) of the experiment which measured the position (initial detection distance) where the ID signal is first detected by any of the antennas for each approach direction is shown. The signs A to L in the figure represent the approaching direction of the worker 10 with respect to the center of the work machine 1, and the numerical value (%) in the figure is the ratio of the initial detection distance to the set communication distance (= initial detection distance / set communication distance × 100) for each approach direction. As can be seen from the radar chart in the illustrated example, when the worker 10 approaches from the rear side (opposite side of the arm member) G of the work machine 1, there is some variation depending on the left and right, but the set communication distance 7.5 m ( ID signal can be detected at ≈100%), but when the worker 10 approaches from the front side (arm member side) A of the work machine 1, it is 50% (≈3.7 m) of the set communication distance 7.5 m. Even if it approaches, the ID signal cannot be detected, and the detection distance of the worker 10 is significantly reduced due to the influence of the arm member 3 on the front side A.

  FIG. 9 (B) is a diagram in which two omnidirectional antennas are respectively attached to the front side A and the rear side G of the main body 2 of the same work machine 1 as in FIG. 9 (A). The radar chart of the experimental result which measured the initial detection distance of the worker 10 who carried the RFID tag like every (A) for every approach direction is shown. The radar chart of the figure cannot sufficiently extend the initial detection distance on the front side (arm member side) A of the work machine 1 even if the number of omnidirectional antennas is increased. This shows that the variation cannot be suppressed. It is conceivable to increase the detection distance on the front side (arm member side) by increasing the communication distance of the RFID tag, but in this case, the detection distance on the rear side (opposite side of the arm member) G is too large. End up. In order to effectively use the worker detection system using the RFID tag as a support tool for the operator, the variation in the detection distance due to the approaching direction of the worker 10 is suppressed as small as possible, and is circular with respect to the center of the work machine 1. It is desirable to be able to detect the worker 10 in a close reception range (for example, a radius of 5 to 15 m from the center of the work machine 1).

  SUMMARY OF THE INVENTION An object of the present invention is to provide a worker detection method and system around a construction machine with an arm member that suppresses variations in detection distance depending on the approach direction.

  Referring to the embodiment of FIG. 1, according to the method for detecting a worker around a work machine according to the present invention, the omnidirectional antenna 17 (see FIG. 3) A directional antenna 14 (see FIG. 2) facing the arm member 3 side is attached together with the active RFID tag 11 (see FIG. 4) for transmitting an ID signal to the worker 10 in the work site 9, It is formed by detecting the worker 10 approaching the periphery of the work machine 1 by receiving the ID signal of either the omnidirectional antenna 17 or the directional antenna 14.

  Further, referring to the embodiment of FIG. 1 and the block diagram of FIG. 5, the worker detection system around the work machine according to the present invention is applied to the main body 2 of the work machine 1 with the movable arm member 3 that operates at the work site 9. An omnidirectional antenna 17 to be attached (see FIG. 3), a directional antenna 14 to be attached to the main body 2 of the work machine 1 toward the arm member 3 (see FIG. 2), and an active that is held by a worker 10 in the work site 9 Type RFID tag 11 (see FIG. 4), and a detection device 20 (see FIG. 5) that outputs a detection signal in response to reception of an ID signal of any one of the omnidirectional antenna 17 and the directional antenna 14 It is.

  Preferably, as shown in FIG. 1, a pair of directional antennas 14 a and 14 b facing the arm member 3 are attached to both sides of the arm member 3 of the main body 2 of the work machine 1. Alternatively, a pair of directional antennas 14 a and 14 b directed toward the arm member 3 may be attached to different height portions of the main body 2 of the work machine 1. More preferably, as shown in FIG. 4, the worker 10 holds a pair of active RFID tags 11a and 11b oriented in the vertical direction and the front-rear direction.

  The method and system for detecting a worker around a work machine according to the present invention includes a directional antenna directed toward the arm member 3 together with the omnidirectional antenna 17 on the main body 2 of the work machine 1 with the movable arm member 3 that operates at the work site 9. 14, and the ID signal transmitted from the active RFID tag 11 held by the worker 10 in the work site 9 is received by either the directional antenna 14 or the omnidirectional antenna 17. Since the worker 10 approaching is detected, the following remarkable effects are produced.

(A) By detecting the ID signal from the movable arm 3 side, in which the detection distance of the omnidirectional antenna 17 is reduced by the influence of the movable arm member 3, by the directional antenna 14 directed toward the arm member 3, the arm member The decrease in the detection distance due to the influence of 3 can be kept small.
(B) By suppressing the variation in the detection distance due to the influence of the arm member 3, it is possible to secure a reception range close to a circle from the center of the work machine 1 and accurately detect the approach of the worker from all directions. It becomes.
(C) By attaching a pair of directional antennas 14a and 14b on both sides of the arm member 3 of the work machine 1 as necessary, a decrease in detection distance due to the influence of the arm member 3 can be further reduced.
(D) Further, by attaching the pair of directional antennas 14a and 14b to different height parts of the work machine 1, a decrease in the detection distance due to the height and posture (standing posture or crouching posture, etc.) of the worker 10 is suppressed to a minimum. I can expect that.
(E) By accurately detecting the approach of the worker from all directions around the work machine, it can be effectively used as a support tool for the operator of the work machine.

  FIG. 1 shows an embodiment in which the detection system of the present invention is applied to a work machine 1 with a movable arm member 3 operating at a work site 9. The working machine 1 in the illustrated example is a general hydraulic excavator having a main body 2 mounted on a drive unit 8 via a swivel 6 and a movable arm member 3 supported at one end by the main body 2. It is. The movable arm member 3 includes a boom that can be raised and lowered and a bendable / extendable arm supported by the boom, and can handle various operations according to an attachment (bucket in the illustrated example) attached to the tip of the arm. The main body 2 includes a driver's seat 4 and a counterweight 5. The main body 2 can be moved to an arbitrary place on the work site 9 by the drive unit 8, and can be rotated 360 degrees on the drive unit 8 by the swivel base 6. In the illustrated working machine 1, the length L2 from the center of the swivel base 6 to the rear edge (opposite side of the arm member) G of the main body 2 is about 3.5 m, and the height H1 of the main body 2 is The length L1 from the tip of the boom to the rear edge (opposite side of the arm member) G of the main body 2 is about 11.14 m. Hereinafter, the detection system of the present invention will be described with reference to the illustrated example. However, the work machine 1 to which the present invention can be applied is not limited to the illustrated example, and the present invention is a work machine 1 having a movable arm member 3. Widely applicable to.

  The detection system of the present invention includes an omnidirectional antenna 17 and a directional antenna 14 that are attached to a main body 2 of a work machine 1, an active RFID tag 11 that is held by a worker 10 in a work site 9, and an omnidirectional antenna. 17 and a directional antenna 14 and a detection device (control unit) 20 that outputs a detection signal in response to reception of the ID signal. The directional antenna 14 is a part (the arm member 3) where the front on the main body 2 of the work machine 1 can be faced so that the worker 10 (RFID tag 11) approaching mainly from the front side (the arm member 3 side) can be detected. And attached to the arm member 3 side) at a portion where the radio wave is not shielded. The omnidirectional antenna 17 can be attached to an arbitrary part on the main body 2 where the radio wave is not shielded by the airframe, but the worker 10 approaching mainly from the rear side (the side opposite to the arm member) G and the side. For example, the RFID tag 11 is attached to a corner on the rear side of the main body 2 of the work machine 1 so that the (RFID tag 11) can be detected. It is desirable to attach any of the antennas 14 and 17 so that they do not protrude from the outer peripheral edge of the work machine 1 as much as possible and do not block the view of the operator of the work machine 1 as much as possible.

  FIG. 2 shows a circularly polarized wave planar antenna having strong directivity in the front direction as an example of the directional antenna 14. As described above with reference to FIG. 9, the worker 10 (RFID tag 11) approaching from the front side (arm member side) A by the influence of the movable arm member 3 only by the omnidirectional antenna 17 mounted on the main body 2. ) Is reduced, but by using the directional antenna 14 directed toward the arm member 3 side, the influence of the movable arm member 3 is suppressed as much as possible, and the sensitivity (gain) of the ID signal from the front side is reduced. It is possible to form a reception range that is almost circular around the center of the work machine 1 (see Experimental Example 1 and Experimental Example 2 described later). However, the directional antenna 14 used in the present invention is not limited to a planar antenna, and a parabolic antenna or a leaky cable antenna may be used as long as the shape does not hinder the above-described operator. The directional antenna 14 in the illustrated example is connected to the detection device 20 via the antenna cable 15 and the connection terminal 15a.

  For example, as shown in FIG. 1, the directional antenna 14 is mounted on the mounting base 16 provided on the ceiling of the driver's seat 4 of the main body 2 so as to be directed downward by an angle θ (for example, about 15 degrees) with respect to the vertical direction. As a result, the worker 10 (RFID tag 11) in front is separated by a set communication distance (for example, about 7.5 m). Alternatively, the directional antennas 14a and 14b are respectively attached to different height portions of the main body 2, and the pair of directional antennas 14a and 14b are different depending on the height and posture (standing posture or squatting posture, etc.) of the worker 10. The height may be collimated. In the present invention, it is sufficient to use a single directional antenna 14 that can cover the entire front side of the work machine 1, but when the movable arm member 3 is arranged at the center of the main body 2 as shown in FIG. The front of both sides of the arm member 3 can be covered by a pair of directional antennas 14 a and 14 b attached to both sides of the arm member 3. In this case, it is desirable to attach the pair of directional antennas 14a and 14b to different height portions.

  FIG. 3 shows a dipole antenna attached to the main body 2 in the vertical direction as an example of the omnidirectional antenna 17. As can be seen from the comparison between FIGS. 9A and 9B, the single omnidirectional antenna 17 may vary in the detection distance on the left and right of the work machine 1. For example, as shown in FIG. The omnidirectional antennas 17a and 17b are mounted vertically on the mounting bases 19 provided on the left and right corners on the rear side (opposite side of the arm member) G of the main body 2 respectively, and the pair of omnidirectional antennas 17a and 17b are used. It is desirable to eliminate variations in the detection distance of the worker 10 (RFID tag 11) approaching from the rear side (opposite side of the arm member) G and the left and right sides. The omnidirectional antenna 17 in the illustrated example is also connected to the detection device 20 via the antenna cable 18 and the connection terminal 18a.

  FIG. 5 shows a block diagram of an example of the detection device 20 connected to the directional antenna 14 and the omnidirectional antenna 17. The detection device 20 in the illustrated example turns on the power lamp 24 by supplying power from the battery 7 of the work machine 1, for example, by turning on the power switch 24 a, and receives receiving circuits (receivers) 21 and 22 via the converter 23. The power is supplied to the relays 25a, 26a, and 28. Normally, the power switch 24a is turned on, and the detection device 20 can be interlocked with the engine of the work machine 1. The receiving circuit 21 is connected to the directional antennas 14a and 14b via a pair of input terminals 15b, and drives the relay 28 in response to reception of the ID signal by any of the directional antennas 14a and 14b to output a detection signal. At the same time, the relay 25a is driven to light the operation lamp 25. The receiving circuit 22 is connected to the omnidirectional antennas 17a and 17b via a pair of input terminals 18b, and detects by driving the relay 28 in response to reception of an ID signal by either of the omnidirectional antennas 17a and 17b. A signal is output and the relay 26a is driven to light the operation lamp 26. The directional antenna 14 and the omnidirectional antenna 17 may be plural or singular.

  According to the illustrated detection device 20, when the worker 10 (RFID tag 11) enters the reception range formed around the center of the work machine 1 by the directional antenna 14 and the omnidirectional antenna 17, the relay 28. Can be driven to output a detection signal. Further, even if the reception of the ID signal by one of the antennas 14 and 17 disappears, the detection signal can be continuously output as long as the ID signal is received by the other antenna. In the embodiment of FIG. 1, the detection device 20 is installed in the driver's seat 4 of the work machine 1, and the alarm device 30 connected to the detection signal output terminal of the detection device 20 is installed in a place where the driver's seat 4 is easily visible. The alarm device 30 causes the operator of the driver's seat 4 to sense the approach of the worker 10 around the work machine 1. As the alarm device 30, an appropriate device belonging to the prior art can be used, but an alarm device that emits sound and emits light in response to a detection signal (e.g., as in Patent Document 4) so that an alarm can be easily confirmed even during work. Patrolite etc.).

[Experimental Example 1]
In order to confirm the variation in the detection distance by the detection system of the present invention, a single directional antenna 14a is provided on the front side A (the ceiling of the driver's seat 4) of the main body 2 of the work machine 1 with the movable arm member 3 shown in FIG. At the same time, a single omnidirectional antenna 17a is attached to the rear side G of the main body 2 (behind the driver's seat 4), and the RFID tag 11 set to a communication distance of 7.5 m is carried as in the experiment of FIG. The worker 10 is made to approach the center of the work machine 1 in the radial direction from a distance, and the ID signal is first detected by either the directional antenna 14 on the front side A or the omnidirectional antenna 17 on the rear side G. An experiment was conducted to measure the position (initial detection distance) for each approach direction. The RFID tag 11 was attached to the upper part of the helmet of the worker 10 approaching the work machine 1. The result of this experiment is shown in the radar chart of FIG.

  The radar chart of FIG. 6 has a variation in the initial detection distance on the opposite side of the arm member 3 as viewed from the directional antenna 14a, but as can be seen from the comparison with the radar chart of FIG. 9, the directional antenna 14a. It can be seen that the ID signal of the worker 10 approaching from the front side can be detected at a set communication distance of 7.5 m (≈100%). That is, by attaching the directional antenna 1 toward the arm member 3 to the main body 2 of the work machine 1, the influence of the movable arm member 3 is suppressed to be small, and the sensitivity (gain) of the ID signal from the front side is increased. It was confirmed that the variation in the detection distance can be kept small. Note that the variation in the detection distance behind the work machine 1 can be expected to be suppressed by attaching a pair of omnidirectional antennas 17a and 17b to the rear side G of the main body 2 (see Experimental Example 2 described later).

  Thus, the provision of “a method and system for detecting a worker around a construction machine with an arm member that suppresses variations in the detection distance depending on the approach direction”, which is an object of the present invention, can be achieved.

  FIG. 4 shows an embodiment in which a worker 10 holds a pair of active RFID tags 11a and 11b in the vertical direction and the front-rear direction. As shown in the radar chart of FIG. 9, the variation in the detection distance depending on the approaching direction to the work machine 1 is not only the front of the work machine 1 affected by the arm member 3 but also the work machine 1 less influenced by the arm member 3. It has also occurred behind. The variation in the detection distance behind the work machine 1 is that the dipole antenna used as the omnidirectional antenna 17 is vertically polarized, so that the polarization of the omnidirectional antenna 17 is shifted depending on the direction of the RFID tag 11. This is thought to be due to the occurrence of a direction that is difficult to receive. By detecting a pair of RFID tags 11a and 11b having different directions in the worker 10 and increasing the number of surfaces that can handle the omnidirectional antenna 17, a detection distance due to a deviation in polarization between the RFID tag 11 and the omnidirectional antenna 17 Can be expected to reduce the variation of

  In the illustrated example, active RFID tags 11a and 11b in the vertical direction and the front-rear direction are attached to the front and right sides of the helmet 12 worn by the worker 10, respectively. If the RFID tags 11 a and 11 b are attached to the helmet 12 as in the illustrated example, even if the worker 10 and the helmet 12 move left and right and up and down with respect to the work machine 1, the polarization deviation of the RFID tag 11 is suppressed to a small level. be able to. The set communication distance of each RFID tag 11 can be appropriately set in consideration of the turning range of the work machine 1 or the like. However, if it is too large, the reliability of the approach detection is impaired, so for example 5 to 15 m, preferably about 5 to 10 m. Is desirable.

[Experimental example 2]
In order to confirm the variation in the detection distance when the helmet 12 with the pair of RFID tags 11a and 11b attached to the worker 10 as shown in FIG. The initial detection distance by either the directional antenna 14 on the front side A or the omnidirectional antenna 17 on the rear side G on the work machine 1 is made close to the center of the work machine 1 in the radial direction from a distance. An experiment to measure was performed. In this experiment, as shown in FIG. 1, a pair of directional antennas 14a on the front side A (the ceiling of the driver seat 4 and the front side step 2a of the main body 2) of the main body 2 of the work machine 1 with the movable arm member 3, 14b is attached, and a pair of omnidirectional antennas 17a and 17b are attached to the rear side G of the main body 2 (the left and right corners behind the main body 2), and the pair of directional antennas 14a and 14b and the pair of omnidirectionality are attached. An ID signal transmitted from the helmet 12 was detected by the antennas 17a and 17b. As shown in FIG. 1C, the directional antennas 14a and 14b are attached so as to collate different heights (about 170 cm and about 80 cm above the ground) according to the posture of the worker 10. The communication distance between the RFID tags 11a and 11b was set to 7.5 m. The results of this experiment are shown in the radar charts of FIGS.

  FIG. 7 shows a radar chart showing an initial detection distance in each approach direction when the worker 10 approaches the work machine 1 in a standing posture, and FIG. 8 shows the worker 10 approaching the work machine 1 in a sitting posture. The radar chart showing the initial detection distance for every approach direction is shown. As can be seen from both the drawings, whether the worker 10 is in the standing posture or the sitting posture, it is set by any one of the directional antennas 14a and 14b on the front side A and the omnidirectional antennas 17a and 17b on the rear side G. The ID signal could be detected at a communication distance of 7.5 m (≈100%), and it was confirmed that a reception range close to a circle was formed around the center of the work machine 1. That is, as in this experimental example, the worker 10 holds the pair of RFID tags 11a and 11b, and the work machine 1 causes the directional antennas 14a and 14b on the front side A and the omnidirectional antenna 17a on the rear side G, By attaching 17b, it becomes possible to detect the approach of the worker from all directions around the work machine without variation, and it is possible to realize a worker detection system that can be effectively used as an operator support tool.

It is explanatory drawing of one Example of the detection system by this invention. It is explanatory drawing of an example of the directional antenna used by this invention. It is explanatory drawing of an example of the omnidirectional antenna used by this invention. It is explanatory drawing of an example of the active type RFID tag held by a worker. It is explanatory drawing of an example of the detection apparatus used by this invention. It is an example of the experimental result which shows the worker detection distance for every approach direction by the detection system of this invention. It is another example of the experimental result which shows the worker detection distance for every approach direction by the detection system of this invention. It is another example of the experimental result which shows the worker detection distance for every approach direction by the detection system of this invention. It is an example of the experimental result which shows the worker detection distance for every approach direction by the detection system using the conventional RFID tag.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Work machine 2 ... Main-body part 2a ... Step 3 ... Movable arm member 3a ... Attachment 4 ... Driver's seat 5 ... Counterweight 6 ... Turntable 7 ... Battery 8 ... Drive part 9 ... Work site 10 ... Worker 11 ... RFID tag DESCRIPTION OF SYMBOLS 12 ... Helmet 14 ... Directional antenna 15 ... Antenna cable 16 ... Mounting base 17 ... Omnidirectional antenna 18 ... Antenna cable 19 ... Mounting base 20 ... Detection apparatus 21 ... Receiver circuit (receiver)
DESCRIPTION OF SYMBOLS 22 ... Receiver circuit (receiver) 23 ... Converter 24 ... Power supply lamp 24a ... Switch 25 ... Actuation lamp 25a ... Relay 26 ... Actuation lamp 26a ... Relay 27 ... Fuse 28 ... Relay 30 ... Alarm device

Claims (8)

An active RFID tag that transmits an ID signal to a worker in the work site is attached to the main body of a work machine with a movable arm member that is operated at the work site and a directional antenna that is directed toward the arm member side together with a non-directional antenna. A method for detecting a worker around a work machine, wherein the worker detects a worker approaching the work machine by receiving an ID signal of either the omnidirectional antenna or the directional antenna. 2. The detection method according to claim 1, wherein a pair of directional antennas directed toward the arm member are attached to both sides of the arm member of the main body of the work machine. The detection method according to claim 1 or 2, wherein a pair of directional antennas facing the arm member are attached to different height portions of the main body of the work machine. 4. The detection method according to claim 1, wherein the worker holds a pair of active RFID tags in a vertical direction and a front-rear direction. A non-directional antenna attached to the main body of a work machine with a movable arm member operating at a work site, a directional antenna attached to the main body of the work machine toward the arm member, and an active to be held by a worker in the work site A worker detection system around a work machine comprising a type RFID tag and a detection device that outputs a detection signal in response to reception of an ID signal of any one of the omnidirectional antenna and the directional antenna. 6. The detection system according to claim 5, wherein the directional antenna is a pair of antennas attached to both sides of the arm member of the main body of the work machine toward the arm member side. The detection system according to claim 5 or 6, wherein the directional antenna is a pair of antennas attached to different height parts of the main body of the work machine toward the arm member side. 4. The worker detection system around a working machine according to claim 1, wherein the active RFID tag is a pair of tags attached to the helmet of the worker in a vertical direction and a front-rear direction.