JP6887306B2 - Garbage truck and person recognition device equipped on it - Google Patents

Description

The present invention relates to a person recognition device that recognizes a worker or the like in the vicinity of a dust inlet of a dust collecting vehicle by an image processing technique, and particularly relates to a technique for identifying the hand or foot thereof.

Conventionally, a garbage truck has been equipped with a dust loading device in a dust loading box provided at the rear of the chassis, and the dust loaded from the dust loading port is loaded into the dust loading box by a rotating plate or a loading box. It is designed to be scraped with a board or the like and loaded into a garbage storage box. In addition, in order to prevent workers who inject dust into the dust inlet from being inadvertently caught in the dust loading device, there are various monitoring systems that monitor people in the vicinity of the dust inlet. Proposed.

For example, in the monitoring system described in Patent Document 1, a camera as an imaging means is arranged in the upper rear part of the dust input box so as to take a picture of the lower dust input port and the rear portion thereof. Then, if the data of the image taken by the camera is transmitted to the image processing device while the dust loading device is operating and it is determined that a person has invaded the entry prohibited area set in advance in this image, the dust is removed. The operation of the loading device is stopped.

Japanese Patent No. 4283568

By the way, in the monitoring system as in the conventional example, the face and head of a person appearing in the image of the camera can be relatively easily identified from the characteristic shapes and positional relationships of the eyes, nose and mouth. However, workers often load the garbage bag into the dust inlet with their hands, and in some cases, kick it with their feet, so to prevent getting caught in the dust loading device, use the face or head. Rather, it is desirable to identify the hand (or foot).

However, the worker's hand opens and closes, and the shape of the object image in the camera image changes greatly depending on the change in its orientation, and the size also changes when wearing gloves or the like. , Identification by image processing is extremely difficult. Similarly, it is difficult to identify the worker's foot by image processing because the shape of the object image changes depending on the orientation and the shape and size of the shoe are different.

The present invention has been made by paying attention to such a problem, and makes it possible to accurately identify the hands and feet of a person in the vicinity based on an image of a camera that captures the vicinity of the dust inlet. The purpose.

Person recognition apparatus of refuse collection vehicles of the present invention, dust inlet of refuse collection vehicles and taken in the vicinity of its by the camera, by entering the data of the image to the vehicle image processing device, waste inlet and the vicinity thereof The target is the one that recognizes the person.

Then, the image processing device compares the feature data of the object image in the image with the feature data including the color information preset for the object attached to the hand or foot of the person, and the object image is the hand or the person's hand or. Whether the person identification unit that determines whether or not it represents a foot and the object image that is determined to represent a hand or foot by the person identification unit are in a predetermined first area of the dust inlet and its vicinity. A person position determination unit for determining whether or not the object is provided, and the person identification unit compares the feature data of the object image in the image with the feature data of the head of the person, and whether or not the object image represents the head of the person. In the person position determination unit, the object image determined to represent the head of the person by the person identification unit is farther from the front edge of the dust inlet than in the first area. It is configured to determine whether or not it is in the second area .

In the person recognition device having such a configuration, the image data from the camera that captures the vicinity of the dust inlet is input to the image processing device, and the person identification unit has the color included in the feature data of the object image in the image. Based on the information, it is determined (identified) that this object image is a person's hand or foot.

That is, as described above, the shape of the object image in the image changes greatly depending on whether the worker's hand is opened or closed or the orientation is changed, and the size also changes when gloves or the like are worn. However, since this does not change the color of the attached object, it can be identified based on the information of this color. Similarly, the worker's foot can be identified based on the color information regardless of the change in orientation, the shape and size of the shoe, and the like.

That is, even a hand or foot that is difficult to identify by image processing can be identified by the color information of the attached object, which improves the recognition accuracy of the person. Therefore, if it is determined that the object image that is determined to represent the hand or foot of a person is in the first area near the dust inlet, the operation of the dust loading device is stopped to ensure safety. Is secured. In addition, the feature data of the object image in the image taken by the camera is also compared with the feature data of the head of the person in the person identification unit. This head feature data is obtained by extracting features such as the state of hair in addition to the size and shape of the entire head in images of the heads of various people taken from above in advance. Then, if the object image is identified as the head, it will be determined to be a person.

Here, it is preferable to configure the image processing device so that the computer device can be connected, and to acquire the color information input by the user to the computer device and set the color information setting as the color information of the feature data. To have a part. That is, in general, the body color of the garbage truck and the color of the designated garbage bag differ depending on the region, and if these colors and the color of the attachment are similar, the worker's information based on this color information There is a risk of misidentifying the hands and feet.

On the other hand, if a computer device is connected as described above so that the color information input by the user can be set as the feature data of the attached object, this can be used as the body color of the garbage truck or the designated garbage bag. By setting a color that is not similar to the color of, it is possible to prevent the misidentification as described above. Therefore, it is possible to identify the person's hand or foot by the color information of the attached object, and thereby the effect of improving the recognition accuracy of the person can be stably ensured.

Specific examples of the attachment to the hand or foot include gloves, shoes, and a wristband, but gloves and shoes may become dirty due to work, and this causes the color to change. If this happens, it may be difficult to identify the wristband, so a wristband is particularly preferable. Moreover, in the case of a wristband, the shape and size do not change much in the image even if the orientation of the hand or foot changes, so this information can also be used for identification.

That is, an attachment such as a wristband is identified and displayed in a manner that makes it easy for the camera to see the image even if the orientation is changed, and at least one of its size, position, and shape is displayed in addition to the color information of the identification display. It is preferable to include the information in the hand or foot feature data. In this way, it becomes possible to more accurately identify a person's hand or foot based not only on the color of the identification display of the attached object but also on its size and shape.

From a different point of view, the present invention is a garbage truck equipped with the above-mentioned person recognition device. That is, the dust loading port opens at the back of the dust loading box provided at the rear of the garbage truck, and the dust loading box is equipped with a dust loading device capable of loading dust into the dust storage box. ing. Then, as described above, when the person position determination unit of the image processing device determines that the object image determined to represent the hand or foot of the person is in the first area, the dust loading device The operation of is stopped by the emergency stop device.

According to the person recognition device of the dust collecting vehicle according to the present invention, when recognizing a person in the vicinity of the dust input port based on the image data of the camera, the size and shape of the object image in the image are likely to change. The camera and the foot can also be accurately identified by the color information of the attached object. Then, based on this determination, the dust loading device is stopped as necessary to ensure safety.

It is a side view which shows the garbage truck which concerns on embodiment of this invention. It is explanatory drawing of the operation of the dust loading device equipped in the garbage truck of FIG. It is a hydraulic circuit diagram of the dust loading device of the garbage truck of FIG. It is the schematic which shows the control device of the garbage truck of FIG. 1 and the input / output state thereof. It is explanatory drawing which shows the schematic structure of the person recognition apparatus equipped in the garbage truck of FIG. It is explanatory drawing which shows the worker who loads a garbage bag into a garbage inlet diagonally from the rear. It is explanatory drawing which shows an example of the image taken by a camera. It is a flowchart which shows an example of an image processing routine. It is a flowchart which shows the determination of the hand and the head of a person. It is explanatory drawing which shows an example of a wristband.

Hereinafter, embodiments in which the present invention is applied to a rotary garbage truck will be described with reference to the drawings. In the following description, for convenience, the front, rear, left, and right of the garbage truck may be simply referred to as front, back, left, and right.

FIG. 1 shows a garbage truck 100 equipped with a person recognition device according to an embodiment of the present invention, and a dust storage box 2 and a dust storage box 3 are provided on the chassis 1 of the garbage truck 100. The opening at the rear of No. 2 and the opening at the front of the garbage truck 3 are communicated with each other. Further, the dust input box 3 is pivotally supported by a pivot axis 3a in the left-right direction provided on the upper portion thereof, and is tilted by a pair of left-right tilting cylinders (not shown).

Further, a rectangular dust input port 4 (see also FIGS. 6 and 7) for charging dust is opened at a lower portion on the back surface of the dust input box 3, and is opened and closed by a tailgate 5 that can be raised and lowered. It is supposed to be done. A switch box 6 for operating the dust loading device and the like is provided on the left side of the dust inlet 4, and above the dust inlet 4, the dust is described in detail later. A camera 7 is arranged so as to photograph the vicinity of the input port 4, and a work light 8 is arranged below the camera 7 so as to illuminate the vicinity of the dust input port 4.

As shown in an enlarged manner in FIG. 2, the inside of the dust loading box 3 is equipped with a dust loading device for loading the thrown dust into the dust storage box 2. The dust loading device of the present embodiment is a so-called rotary type in which the rotating plate 10 (loading member) scoops up the dust and the pushing plate 20 pushes the dust into the dust storage box 2. That is, first, the rotating shaft 11 is erected in the lower part of the dust input box 3 so as to extend in the width direction thereof, and the base end side of the rotating plate 10 is fixed to the rotating shaft 11.

In the illustrated example, a hydraulic motor 13 capable of forward / reverse rotation is connected to the end of the rotating shaft 11 via a speed reduction mechanism 12. Therefore, the rotation of the hydraulic motor 13 is torqued up by the speed reduction mechanism 12 and transmitted to the rotating shaft 11, and the rotating plate 10 is rotated integrally with the rotating shaft 11, so that the tip portion thereof has a substantially semicircular cross section. It comes to move in the front-rear direction along the bottom wall of the dust input box 3 formed in.

On the other hand, the push-in plate 20 is provided above the rotary plate 10 over the entire width direction of the dust input box 3, and can swing in the front-rear direction around the left-right swing shaft 21 provided above the push-in plate 20. Is supported by. Further, the push plate 20 is provided with an extension portion 22 extending upward from the swing shaft 21, and a push cylinder 24 is erected between the extension portion 22 and the support pin 23 in front of the extension portion 22. The push-in plate 20 is swung in the front-rear direction by the expansion / contraction operation.

That is, as shown by the solid line in FIG. 2, when the pushing plate 20 is at the position where it swings most toward the dust storage box 2 (advance limit position), the rotating plate 10 moves upward without interfering with the pushing plate 20. The push-in plate 20 swings toward the dust input port 4 side after this. Then, even after the push-in plate 20 swings most toward the dust inlet 4 side and reaches the retreat limit position shown by the virtual line in FIG. 2, the rotation of the rotating plate 10 is continued.

The rotating plate 10 that rotates in this way scrapes the dust toward the dust storage box 2 side, and temporarily stops at the set stop position extending to the front dust storage box 2 side as shown by the solid line in FIG. Then, the push plate 20 swings toward the dust storage box 2 and pushes the dust on the rotating plate 10 into the dust storage box 2. Then, when the push-in plate 20 reaches the above-mentioned advance limit position again, the rotating plate 10 will rotate upward again.

By repeating the rotation of the rotating plate 10 and the swinging of the pushing plate 20 in synchronization with each other in this way, the dust thrown into the dust loading box 3 is continuously loaded into the dust storage box 2 (hereinafter, dust stacking). It is called a built-in operation). The configuration of the hydraulic circuit and the electronic control device (control system) for operating the rotary plate 10 and the push plate 20 in this way will be described below, but for that purpose, the rotary plate 10 and the push plate 10 are inside the dust input box 3. Switches LS1 to LS4 for detecting the position of the plate 20 are provided.

That is, as shown in FIG. 2, the switches LS1 and LS2, which are turned on when the push plate 20 is in the forward limit position or the reverse limit position, and the switches LS1 and LS2, which are turned on when the rotary plate 10 is in the set stop position, are turned on. A switch LS3 and a switch LS4 that are turned on when the rotating plate 10 is rotated by a predetermined angle in a positive direction (clockwise in FIG. 1) from the set stop position and turned off when the rotating plate 10 is further rotated by a predetermined angle are provided. Has been done.

The switches LS1 and LS2 are designed to detect dogs (not shown) provided at the end of the swing shaft 21 of the push plate 20, and the switches LS3 to LS4 are the rotary shafts 11 of the rotary plate 10. A dog (not shown) provided at the end is detected. Further, as these switches LS1 to LS4, for example, a limit switch, a photoelectric switch, a proximity switch and the like can be used.

Further, in the switch LS4, as shown by hatching in FIG. 2, the rotating plate 10 descends while rotating backward from directly below the front edge portion 4a of the dust inlet 4, and the trailing edge portion 4b of the dust inlet 4 It is a sensor for detecting that the rotating plate 10 is operating in the vicinity of the dust inlet 4 for detecting the angle range Z up to the closest distance to the dust inlet 4. Since there is a risk that the rotating plate 10 may involve a part of the operator's body in the angle range Z, it is referred to as a dangerous angle range Z below.

Further, as shown in FIGS. 1 and 2, emergency stop buttons 60 and 61 for stopping the operation of the dust loading device, an emergency stop plate 62, and the like are arranged in the vicinity of the dust input port 4. .. As shown in FIG. 1, an emergency stop button 60 is arranged in the switch box 6 on the left side of the dust inlet 4, and as shown by a broken line in FIG. 2, an emergency stop button 61 is provided on the right side of the dust inlet 4. It is arranged. The emergency stop plate 62 is arranged below the dust inlet 4 so as to turn on / off the switch SW3.

-Control system for dust loading device-
Next, with reference to FIGS. 3 and 4, a control system for operating the dust loading device as described above will be described. This control system consists of a hydraulic circuit that controls the hydraulic pressure supplied to the hydraulic motor 13 and the push cylinder 24 of the dust loading device, and a control device that outputs control signals to the electromagnetic control valves V1 and V2 provided in the hydraulic circuit. It is equipped with a PLC (Programmable Logic Controller).

First, the hydraulic circuit will be described with reference to FIG. 3. This hydraulic circuit controls the hydraulic pump P, the oil reservoir T, the electromagnetic control valve V1 for controlling the push cylinder 24, and the hydraulic motor 13. The electromagnetic control valve V2 of the above is provided. Although not shown, the driving force of the engine is transmitted to the hydraulic pump P via the PTO (power take-off).

As an example, the electromagnetic control valves V1 and V2 are each composed of an electromagnetic direction switching valve having 6 ports and 3 positions. When the solenoid SOLa is excited by the control device PLC, the electromagnetic control valve V1 switches to the first communication position (upper position in the figure), and the hydraulic oil from the hydraulic pump P is introduced into the rod-side oil chamber of the pair of push cylinders 24. When the solenoid SOLb is excited by the control device PLC, the solenoid SOLb is switched to the second communication position (lower position in the figure), and the hydraulic oil is supplied to the oil chamber on the head side.

When the hydraulic oil is supplied from the electromagnetic control valve V1 to the oil chamber on the head side, the pair of push cylinders 24 are extended and the push plate 20 is swung forward. On the other hand, when the hydraulic oil is supplied to the rod-side oil chamber, the pair of push cylinders 24 contract and cause the push plate 20 to swing rearward. Further, when neither of the solenoids SOLa and SOLb is excited, the electromagnetic control valve V1 returns to the neutral position (center position in the figure).

On the other hand, when the solenoid SOLc is excited, the electromagnetic control valve V2 switches to the first communication position (the lower position in the figure), supplies hydraulic oil to the oil chamber on the forward rotation side of the hydraulic motor 13, and the hydraulic motor 13 In addition to the normal rotation operation, the push cylinder 24 can also be expanded and contracted. On the other hand, when the solenoid SOLd is excited, the electromagnetic control valve V2 switches to the second communication position (upper position in the figure), supplies hydraulic oil to the oil chamber on the reversing side of the hydraulic motor 13, and reverses the hydraulic motor 13. Activate.

Further, when neither of the solenoids SOLc and SOLd is excited, the electromagnetic control valve V2 returns to the neutral position (center position in the figure). When both the electromagnetic control valves V1 and V2 are in the neutral position, the hydraulic oil returns to the oil reservoir T. In the illustrated hydraulic circuit, reference numeral V3 is a check valve, and reference numeral V4 is a relief valve for setting an upper limit of the discharge pressure of the hydraulic pump P.

Next, the input / output state of the signal of the control device PLC or the like will be described with reference to FIG. First, power is supplied to the control device PLC by the battery BT shown in the upper left of the figure (below the monitor 93 in the figure). A key switch SWK, a PTO switch SWP, a relay coil CR1 and the like of the garbage truck 100 are interposed in the energizing line K2 extending from the positive electrode of the battery BT to the right side of the drawing and reaching the ground line K1.

Further, the upstream end of the energizing line K3 is connected so as to branch off from the energizing line K2 between the key switch SWK and the battery BT, and the relay coil CR1 is connected to the upstream side (the side close to the battery BT). The contact cr1 is interposed. A power lamp L is interposed in the energization line K3, and when the relay coil CR1 is turned on and the contact cr1 is closed, the power lamp L is turned on by energizing the energization line K3.

Further, the upstream end of the energization line K4 is connected so as to branch off from the energization line K3 between the contact cr1 of the relay coil CR1 and the power lamp L, whereby the signal power supply unit of the control device PLC (FIG. Power is supplied to (not shown). That is, when the contact cr1 is closed as described above, power is supplied to the control device PLC via the energizing lines K3 and K4.

Further, the energizing line K5 branching from the energizing line K4 always energizes the control device PLC during the dust loading operation of the dust loading device. That is, the energization line K5 is a line for inputting a so-called loading continuation signal, which is opened and closed in response to the operations of the emergency stop buttons 60 and 61 and the emergency stop plate 62 described above with reference to FIG. Switches SW1 to SW3 are provided.

When the energization (that is, the input of the loading continuation signal) is cut off by these switches SW1 to SW3, the operation of the control device PLC is stopped. As a result, all the output of the control signal from the control device PLC for exciting the solenoids SOLa to SOLd of the electromagnetic control valves V1 and V2 is cut off, and the electromagnetic control valves V1 and V2 return to the neutral position, resulting in dust. The operation of the loading device is stopped.

Further, a plurality of branch lines branching from the middle of the energizing line K4 are connected, and the switches LS1 to LS4 described above are interposed in each of these branch lines with reference to FIG. The signals from the switches LS1 to LS3 are input to the control device PLC, and the positions of the rotating plate 10 and the pushing plate 20 of the dust loading device, that is, the operating status is detected based on these signals. To.

In addition to the above switches LS1 to LS3, on the input side to the control device PLC, although not shown, a start / stop switch for the dust loading device, a single-acting or continuous selection switch for the dust loading operation, A switch for selecting a dust loading operation and a dust discharging operation, a switch for operating the rotating plate 10 and the pushing plate 20 independently, a switch for tilting and opening the dust loading box 3 and the like are also connected.

Further, as described above with reference to FIG. 2, the signal from the switch LS4 that detects that the rotating plate 10 is in the dangerous angle range Z is input to the image processing unit 9 instead of the control device PLC. It has become like. In response to this, the central processing unit CPU of the image processing unit 9 opens the relay switch SW4 when a stop signal is issued from the image processing unit DSP, and energizes the control device PLC by the energization line K5, which will be described in detail later. To shut off.

While various switches are connected to the input side as described above, the solenoids SOLa to SOLd of the electromagnetic control valves V1 and V2 described above are connected to the output side of the control device PLC with reference to FIG. .. Then, the control device PLC sets the corresponding solenoids SOLa to SOLd in order to operate the hydraulic motor 13 and the push cylinder 24 according to a preset procedure based on the signals input from the switches SW1 to SW3, LS1 to LS3 and the like. It is programmed to output.

That is, for example, when the dust loading device operates the dust loading operation, both the key switch SWK and the PTO switch SWP on the energizing line K2 are closed and the relay coil CR1 is energized. As a result, the contact cr1 of the relay coil CR1 is closed, so that the control device PLC becomes operable by being energized by the energizing lines K3 to K5, and a control signal is output to the solenoids SOLa to SOLd as appropriate. become.

Upon receiving this control signal, the solenoids SOLa to SOLd are excited, and the positions of the electromagnetic control valves V1 and V2 are appropriately switched, so that the hydraulic motor 13, the push cylinder 24, and the like are supplied with hydraulic pressure. As a result, the hydraulic motor 13, the push cylinder 24, and the like operate, respectively, and as described above with reference to FIG. 2, the rotation of the rotary plate 10 and the swing of the push plate 20 are repeated in synchronization with each other.

Specifically, first, as shown by the solid line in FIG. 2, the push plate 20 is in the forward limit position and the on signal is output from the switch LS1, and the rotary plate 10 is in the set stop position and is also on from the switch LS3. When the signal is output, the control device PLC that receives the signal of the start switch outputs the control signal, the electromagnetic control valve V2 is switched to the first communication position, and the hydraulic motor 13 starts the normal rotation operation. As a result, the rotating plate 10 starts to rotate upward.

Then, when a predetermined period elapses, a control signal is output from the control device PLC to the solenoid SOLa of the electromagnetic control valve V1, the electromagnetic control valve V1 is switched to the first communication position, and the push cylinder 24 starts the contraction operation. As a result, the push-in plate 20 swings toward the rear dust input port 4, and when the push-in plate 20 reaches the retreat limit position, an ON signal is output from the switch LS2.

In response to this, the control device PLC stops the output of the control signal to the solenoid SOLa, so that the electromagnetic control valve V1 returns to the neutral position and the swing of the push plate 20 is stopped. Further, while the push-in plate 20 is swinging in this way, the rotation of the rotating plate 10 continues, and the dust is scraped into the dust storage box 2 side, and the push-in plate 20 that rotates in this way The setting stop position is reached, and an on signal is output from the switch LS3.

In response to this, the control device PLC stops the output of the control signal to the solenoid SOLc of the electromagnetic control valve V2, so that the electromagnetic control valve V2 returns to the neutral position and the rotation of the hydraulic motor 13 is stopped. Further, the control device PLC outputs a control signal to the solenoid SOLb of the electromagnetic control valve V1, the electromagnetic control valve V1 is switched to the second communication position, and the push cylinder 24 starts the extension operation, whereby the push plate 20 Begins to swing forward.

In this way, the push plate 20 swinging toward the front dust storage box 2 pushes the dust on the rotating plate 10 into the dust storage box 2, and when the forward limit position is reached, the on signal is output from the switch LS1. In response to this, the control device PLC stops the output of the control signal to the solenoid SOLb, so that the electromagnetic control valve V1 returns to the neutral position and the push cylinder 24 is extended, that is, the push plate 20 is moved forward. The rocking stops and a series of operations ends.

As shown in FIG. 4, the image processing unit 9 described below is interposed in the energizing line K5 in which the switches SW1 to SW3 for emergency stop are interposed, and the image processing is performed. A changeover switch SWS for energizing the control device PLC by a bypass line K6 that bypasses the unit 9 is also provided. Further, a work light 8 and a pilot lamp 91 are connected to the output side (right side of FIG. 4) of the image processing unit 9, and lighting control thereof is performed.

-Person recognition device and emergency stop device-
By the way, when the dust loading device is performing the dust loading operation as described above, the operator who is loading the dust into the dust loading port 4 may be inadvertently caught in the rotating plate 10 or the like. Therefore, in the garbage truck 100 of the present embodiment, the camera 7 is arranged so as to take a picture of the vicinity of the dust input port 4, and it is determined by image processing that a person in the vicinity of the dust input port 4 is in a dangerous area. If so, the operation of the dust loading device is immediately stopped.

That is, in addition to appearing in FIGS. 1 and 2 above, as shown in FIGS. 5 and 6, a camera 7 is arranged above the back surface of the dust input box 3, that is, above the dust input port 4. The image pickup lens 70 is directed obliquely downward at the rear. This camera 7 is originally used as a back camera for the driver of the garbage truck 100 to monitor the rear, and as shown in FIG. 7, a predetermined range of the dust input port 4 and the rear thereof is photographed. It has become like.

Then, in order to photograph the rear of the dust inlet 4, the optical axis A of the image pickup lens 70 of the camera 7 is turned vertically downward to the rear, and the person H in the vicinity of the dust inlet 4 is photographed from above. It has become. Further, the work light 8 arranged below the camera 7 is also directed diagonally downward to the rear, irradiates light substantially parallel to the optical axis A of the image pickup lens 70, and substantially in the direction in which the person H is photographed by the camera 7. It is designed to irradiate from the front.

By shining the illumination light from the front in this way, the appearance of the person H does not change significantly even if the posture of the person H changes slightly, so even in a dark place such as at night or in an underground space, in the captured image. The change in the object image of the person H is not so large. Further, since the work light 8 is arranged below the camera 7, it is possible to suppress the contamination of the work light 8 due to rain and wind, and it is easy for an operator or the like to visually recognize the on / off of the work light 8.

Then, as shown in FIG. 4, the camera 7 is operated via the signal distributor 92 with the monitor 93 for monitoring and the image processing unit 9 (an image processing device, for example, as shown by a broken line in FIG. 1). It is connected to (arranged around the seat). The monitor 93 provides an image of the camera 7 to the driver of the garbage truck 100, and the same image is transmitted to the image processing unit 9 to determine whether or not a worker or the like is in a dangerous area. To.

That is, FIGS. 5 to 7 above show a worker (person H) standing in the vicinity of the garbage input port 4 with both arms extended forward to load the garbage bag. The image processing unit 9 determines whether or not the user is in a dangerous area. Therefore, as schematically shown in FIG. 5, the image processing unit 9 is provided with an image processing unit DSP that inputs image data from the camera 7 and performs known image processing described below.

Further, the image processing unit 9 includes a central processing unit CPU that executes a predetermined program to perform various controls, a memory M that stores data used in the central processing unit CPU and the image processing unit DSP, and central processing. A relay switch SW4 that opens and closes in response to a command from the CPU is also provided. Then, if the image processing unit DSP determines that the person H is in a dangerous area, the central processing unit CPU opens the relay switch SW4.

Here, as described above with reference to FIG. 4, both the key switch SWK and the PTO switch SWP are closed during the loading operation of the dust loading device, and the control device PLC is energized by the energizing lines K3 to K5. ing. Since the image processing unit 9 is interposed in the middle of the energization line K5, when the relay switch SW4 is opened as described above, the energization to the control device PLC is cut off and dust is loaded. The operation of the device will be stopped.

That is, an emergency stop device for stopping the operation of the dust loading device is configured by the central processing unit CPU of the image processing unit 9 and the relay switch SW4. In addition to functioning as an emergency stop device, the central processing unit CPU turns on the work light 8 while the image processing unit 9 is operating, and turns it off when it is not operating due to a failure or the like. It also functions as a lighting control unit that controls the on / off of the work light 8.

By turning off the work light 8 when the image processing unit 9 is not operating in this way, the worker (person H) who loads the garbage bag easily notices that the emergency stop device by image processing is not operating, and loads the garbage. Greater care will be taken not to get caught in the device. The image processing unit 9 also includes an image output unit VOP that receives a command from the central processing unit CPU and displays the result of image processing on the monitor 93, a camera control unit (not shown) that controls the camera 7. It is provided.

-Image processing routine-
The image processing unit DSP is a general integrated circuit that performs known image processing logic at high speed. For example, binarization processing of input image data and each pixel close to each other in the binarized image data. Labeling process that makes the area of the object image, person identification process that identifies that the area of the object image aread by labeling is a person image, and determination of whether the position of the object image identified as the person image is a dangerous area. Performs the person position determination process.

Specifically, the image processing routine will be described with reference to the flowchart of FIG. 8. First, the binarization processing is performed in step S1 after the start. This is, for example, a process in which the maximum luminance value is set when the luminance value for each pixel of the input image data is equal to or more than a preset threshold value, and the minimum luminance value is set when the luminance value is less than the threshold value. The generated binarized image data is obtained by removing most of the effects of noise and changes in the amount of light.

While performing the binarization process in this way, the input image data is temporarily stored in the memory M, and the color information included in the input image data is used for the determination (step S3) of the hand of the person H, which will be described later. Alternatively, color binarization processing is also performed on the input image data, and the one in which the hue value for each pixel is within the preset range is extracted as the color information, while the other hue information is deleted. Good.

Next, in step S2, a labeling process is performed. This is to regionize pixels that are close to each other in the binarized image data. For example, it is a process that considers a plurality of pixels that belong to the same luminance value and are close to each other within a predetermined distance as one region. .. The labeling process is performed on the entire image plane, and each area is recognized as an object image.

Then, in the following step S3, the person identification process for each of the object images is performed. In the present embodiment, the camera 7 arranged above the dust inlet 4 captures the vicinity of the dust inlet 4 below, so that the image shows the person H as shown in FIG. 7 as an example. The head of is displayed large. Therefore, by referring to preset feature data of the head, for example, data indicating the size and shape thereof, an object image satisfying the conditions of the feature data is determined to be the head of the person H.

Further, as will be described later with reference to FIG. 10, in step S3, the feature data of the wristband LB worn on the wrist of the person H, that is, the color, shape, and size of the striped pattern SP (identification display) displayed therein. By referring to the data indicating the stripes and the like, it is determined that the object image satisfying the condition of the feature data is the hand of the person H. Then, in step S4, it is determined whether or not the object image identified as the hand or the head of the person H is in a preset dangerous area.

In the present embodiment, the dangerous area differs between the hand and the head of the person H, and as shown in FIG. 7, the dangerous area is larger than the central boundary line B1 of the front edge portion 4a and the trailing edge portion 4b of the dust inlet 4. The front side, that is, the back side of the dust inlet 4, is regarded as the first area which is a dangerous area for the hand. Further, the area corresponding to the entire dust input port 4, that is, the area in front of the trailing edge portion 4b (boundary line B2) of the dust input port 4 is a second area which is a dangerous area for the head. ..

Then, it is determined whether or not the position coordinates of the pixels forming the outer shape of the object image (region) identified as the hand of the person H as described above are in front of the boundary line B1 of the first area. It is also determined whether or not the position coordinates of the pixels forming the outer shape of the object image (region) identified as the head of the person H as described above are in front of the boundary line B2 of the second area. In this way, it is determined whether or not the person H is in a dangerous area.

If it is determined affirmatively that at least one of the hand and the head of the person H is in the dangerous area (first and second areas) (YES), the process proceeds to step S5 of the dust loading device. In order to stop the operation, a stop signal is output to the central processing unit CPU, and the image processing routine is terminated (end). On the other hand, if it is negatively determined that neither the hand nor the head of the person H is in the dangerous area (NO), the image processing routine is terminated without outputting the stop signal (end).

Then, when the stop signal is emitted from the image processing unit DSP, the central processing unit CPU that receives the stop signal receives the signal if the signal from the switch LS4 is on, that is, if the rotating plate 10 is in the dangerous angle range Z. , The relay switch SW4 is opened. That is, by energizing a relay coil (not shown) to open the contact of the switch, energization of the control device PLC by the energization line K5 is cut off.

As a result, the operation of the control device PLC is forcibly stopped, so that even if there is some abnormality in the control device PLC, the energization of all the solenoids SOLa to SOLd of the electromagnetic control valves V1 and V2 is stopped. Become. Therefore, all the electromagnetic control valves V1 and V2 in the first communication position or the second communication position return to the neutral position, and as a result, the operation of the hydraulic motor 13 and the push cylinder 24 is immediately stopped.

By executing step S3 of the flow of FIG. 8, the image processing unit DSP compares the feature data of the object image with the feature data of the hand or head of the person (for the hand, the striped pattern SP of the wristband LB). A person identification unit for determining whether or not the object image represents a person's hand or head is formed, and further, by executing step S4, the object image representing the person's hand or head is a dust input port. A person position determination unit for determining whether or not the user is in a predetermined area in the vicinity is configured.

Although not shown, the image processing unit 9 can be connected to a computer device such as a general-purpose personal computer by a known method to set the color information of the wristband LB. That is, the image processing unit 9 is provided with an input setting program that inputs the hue value data set by the user and stores it in the memory M as the color information of the feature data. By executing this routine, the central processing unit 9 is provided. The CPU constitutes a color information setting unit that allows the user to set the color information of the feature data.

-Identification of a person's hand, etc.-
Next, a procedure for identifying a person's hand or head in steps S3 and S4 of the flow of FIG. 8 and determining whether or not they are in a dangerous area will be described in detail with reference to the flowchart of FIG. To do. As described above, in the present embodiment, the camera 7 arranged above the dust input port 4 is used to take a picture so as to look down on the vicinity of the dust input port 4, and as shown in FIG. 7 above, the image is captured. The head of the person H is displayed large.

Therefore, in order to recognize that the person is H, it is conceivable to first identify the head, but as described above with reference to FIGS. 5 and 6, the worker (person H) is the dust input port. When the garbage bag is put into No. 4, both arms may be extended diagonally forward and upward to load the garbage bag. Therefore, in order to prevent the hand from being caught in the dust loading device, it is desirable to identify the hand rather than the head of the person H.

However, the shape of a human hand changes greatly depending on whether it is opened or closed, and the shape of the object image in the image changes greatly depending on the direction in which the image is taken. In some cases, this will also change the size. For this reason, it is considered extremely difficult to identify a human hand by image processing.

In consideration of such an actual situation, in the present embodiment, a wristband LB as shown in FIG. 10 is attached to the wrist of the operator, and the striped pattern SP (identification display) displayed so as to orbit the wristband LB. ), In particular, the color is referred to as feature data, thereby identifying the hand. In this way, the color of the striped pattern SP orbiting the wristband LB can be similarly identified even if the direction of the hand is changed.

Specifically, first, in step S31 after the start of the flow of FIG. 9, the feature data of the wristband LB set in advance, that is, the feature data indicating the color, size, shape, etc. of the striped pattern SP is obtained. With reference to this, it is determined whether or not the object image in the image satisfies the condition of this feature data. The color of the striped pattern SP is set in advance by the user and stored in the memory M of the image processing unit 9 so that the color of the striped pattern SP can be definitely distinguished from the body color of the garbage truck 100 and the color of the local garbage bag.

Then, if the color of the object image does not match the color of the striped pattern SP, it is negatively determined (NO) that the object image is not the hand of the person H, and the process proceeds to step S32 described later, and this time the object image is the person H. Judge whether it is the head or not. On the other hand, if the colors of the striped pattern SP match, it is determined affirmatively (YES) that the object image is the hand of the person H, and the process proceeds to step S41. At this time, not only the color information but also the shape and size of the object image may be used for the determination.

The process of step S41 corresponds to step S4 of the flow of FIG. 8, and determines whether or not the object image determined to be a hand as described above is in the first area. That is, as described above with reference to FIG. 7, if the object image identified as a hand is in front of the boundary line B1 near the center of the dust inlet 4, it is affirmed that the object is in the first area. Judgment (YES in step S41).

In this case, YES is determined in step S4 of the flow of FIG. 8, and the process proceeds to step S5. As described above, a stop signal is output to the central processing unit CPU in order to stop the operation of the dust loading device. To do. On the other hand, if it is negatively determined in step S41 that the object image is not in the first area (NO), the process proceeds to step S51 described later. That is, even if the object image is identified as a hand, the operation of the dust loading device is not stopped unless it is in the first area.

Further, in step S32, in which the color of the striped pattern SP of the wristband LB does not match in step S31 and the object image is negatively determined not to be a hand, the object image is the head of the person H this time. Judge whether or not. This refers to preset head feature data, that is, data indicating, for example, the size and shape of the head, the condition of the hair, and the size and shape of the attachment to the head and face. An object image that satisfies the condition of the feature data is tentatively determined to be the head of the person H (step S33).

The object image tentatively determined to be the head in this way is processed to be distinguished from other object images. That is, in the present embodiment, the change in the position of the object image is detected by the difference processing (processing for obtaining the difference in the brightness value for each pixel) of a plurality of image data input from the camera 7 in time series. Then, this change in position, that is, the moving distance of the object image, is divided by the time required for it (the time interval for acquiring the image data) to calculate the moving speed of the object image.

In step S34, it is determined whether or not the moving speed calculated in this way is equal to or less than a preset threshold value. This threshold value is set in advance by an experiment or the like so that the moving speed of the head of the worker who throws the dust into the dust throwing port 4 and the moving speed of the thrown dust can be distinguished. Therefore, if the calculated movement speed is higher than the threshold value, it is determined that the movement speed is not the head of the person H because the movement is too fast, a negative determination is made, and (NO) the process proceeds to step S51 described later.

On the other hand, if it is determined affirmatively that the moving speed is equal to or less than the threshold value in step S34 (YES), it is determined that the object image is the head of the person H (main determination), and the process proceeds to step S42. The process of step S42 corresponds to step S4 of the flow of FIG. 8, and whether the object image determined to be the head as described above is in the second area described above with reference to FIG. It is to judge whether or not.

Then, if the object image identified as the head is in front of the trailing edge 4b (boundary line B2) of the dust inlet 4, it is determined affirmatively that it is in the second area (YES in step S42). ). In this case, YES is determined in step S4 of the flow of FIG. 8, and the process proceeds to step S5. As described above, a stop signal is output to the central processing unit CPU in order to stop the operation of the dust loading device. To do.

On the other hand, if it is negatively determined in step S42 that the object image is not in the second area, the process proceeds to (NO) step S51, and all the object images in the image have the above-mentioned hands and head. If it is a negative determination (NO), the process returns to step S31 and the above-described procedure is repeated. On the other hand, if all the object images have been identified, an affirmative determination (YES) is made in step S51, and the routine ends.

As described above, in the person recognition device of the garbage truck according to the present embodiment, first, the camera 7 is arranged above the dust input port 4 in the dust input box 3 at the rear of the vehicle body, and the dust input port 4 below. Take a picture of the vicinity of. Then, the image data from the camera 7 is input to the image processing unit 9, and if it is determined by the image processing that the person H is in a dangerous area, the operation of the dust loading device is stopped.

Then, when recognizing the person H in the vicinity of the dust input port 4 based on the image data obtained by the camera 7, in the present embodiment, the work light 8 provided below the camera 7 is turned on, and the person H ( For example, the light is radiated toward the worker who loads the dust. By disposing it below the camera 7 in this way, it is possible to suppress the contamination of the work light 8 due to rain and wind and to irradiate the light stably.

Further, in the present embodiment, the work light 8 is provided so as to irradiate the person H with light substantially parallel to the optical axis A of the image pickup lens 70 of the camera 7, whereby the person H is photographed in the direction of shooting. It will illuminate almost from the front. Therefore, even if the posture is slightly changed, the appearance does not change significantly, and the change in the object image in the captured image is not so large, so that the recognition failure or misidentification of the person H is suppressed.

Further, the feature data of the object image in the image thus captured is compared with the feature data of the hand of the person H. Since this feature data includes information on the color of the wristband LB, even if the hand of the person H opens or closes and its shape changes significantly, the size can be increased by wearing gloves or the like. Even if it changes, it can be identified as a hand regardless of it. If the object image determined to be a hand is in the first area on the back side of the dust inlet 4, the safety can be ensured by stopping the operation of the dust loading device.

Further, in the present embodiment, not only the hand of the person H but also the head thereof is identified, and if this is in the second area corresponding to the entire dust inlet 4, the dust loading device Safety can be ensured by stopping the operation of.

Furthermore, when the person H in the vicinity of the dust inlet 4 is recognized by the image processing in this way, the work light 8 is turned on, while the work light 8 is turned off when the image processing unit 9 is out of order such as a failure. Will be done. Therefore, the worker (person H) easily notices that the emergency stop device by image processing does not operate and pays more attention to it, which is preferable in suppressing an accident. In particular, in the present embodiment, since the work light 8 is arranged below the camera 7, it is easy to visually recognize its on / off.

-Other embodiments-
Although the preferred embodiment of the present invention has been described above, this merely shows one specific example and does not particularly limit the present invention. Therefore, the specific configuration and the like can be appropriately redesigned. is there. For example, in the above embodiment, the image processing unit 9 is interposed in the energization line K4 to the control device PLC, and the energization to the control device PLC is cut off by opening the relay switch SW4. Not limited.

That is, for example, when the image processing unit 9 determines that the person H is in a dangerous area, a stop signal is output to the control device PLC, and the control device PLC receives the stop signal, and the solenoids SOLa of the electromagnetic control valves V1 and V2 The output of the control signal to the SOLd may be stopped, and any other configuration capable of stopping the operation of the dust loading device can be adopted.

Further, in the above-described embodiment, the color of the striped pattern SP of the wristband LB worn on the wrist of the worker is used as feature data to identify the hand by image processing, and the head of the worker is also identified. I try to do it, but it is not limited to this. For example, the head of the worker may not be identified, or the wristband LB may be attached to the foot in addition to the hand so that the foot can be identified by the color of the striped SP. May be good.

Alternatively, the glove worn by the operator may be provided with an identification display such as the striped pattern SP to identify the glove, or the glove itself may be identified based on the color of the glove itself. You may. Similarly, the shoe worn by the worker on the foot may be provided with an identification mark to identify the shoe, or the shoe itself may be identified based on the color of the shoe itself.

Further, in the above-described embodiment, the work light 8 is arranged below the camera 7 and is irradiated with light along the optical axis A of the image pickup lens 70. However, it is not necessary to do this, and the work is performed. The lights 8 may be arranged above or to the left or right of the camera 7, or may be arranged to the left or right of the conventional general dust input port 4.

Furthermore, in the above embodiment, the case where the present invention is applied to the garbage truck 100 equipped with the so-called rotary dust loading device is described, and the main parts of the dust loading device are the rotating plate 10 and the pushing plate. The main part of the dust loading device may be composed of an elevating plate and a pushing plate, and the structure is not particularly limited.

100 Garbage truck 1 Chassis 2 Dust storage box 3 Dust input box 4 Dust input port 7 Camera 9 Image processing unit (image processing device)
10 Rotating plate (dust loading device)
13 Hydraulic motor (dust loading device)
20 Push-in plate (dust loading device)
24 Push-in cylinder (dust loading device)
H person LB wristband (attachment to hand)
SP striped pattern (identification display)
Central processing unit (emergency stop device) of CPU image processing unit
Image processing unit (person identification unit, person position determination unit) of the DSP image processing unit
SW4 Image processing unit relay switch (emergency stop device)

Claims (4)

A person in a garbage truck who takes a picture of the garbage truck's dust inlet and its vicinity with a camera and inputs the image data to an in-vehicle image processing device to recognize the person in the garbage truck and its vicinity. It ’s a recognition device,
The image processing device is
The feature data of the object image in the image is compared with the feature data including the color information preset for the object attached to the hand or foot of the person, and it is determined whether or not the object image represents the hand or foot of the person. Person identification section and
A person position determination unit for determining whether or not an object image determined to represent a hand or foot by the person identification unit is in a predetermined first area of the dust inlet and its vicinity is provided.
The person identification unit is configured to compare the feature data of the object image in the image with the feature data of the head of the person and determine whether or not the object image represents the head of the person.
In the person position determination unit, whether or not the object image determined by the person identification unit to represent the head of the person is in the second area farther from the front edge of the dust inlet than the first area. A person recognition device for a garbage truck, which is configured to determine whether or not. The person recognition device for a garbage truck according to claim 1, wherein the attachment to the hand or foot includes gloves, shoes, and a wristband. The dust collection according to claim 1 or 2, wherein the feature data includes information on the color of the identification display represented on the attachment and at least one information on the size, position, and shape thereof. Car person recognition device. The dust loading port opens at the back of a dust loading box provided at the rear of the garbage truck, and the dust loading box is equipped with a dust loading device capable of loading dust into the dust storage box.
When the person position determination unit of the image processing device determines that an object image determined to represent a person's hand or foot is in the first area, the operation of the dust loading device is stopped. A dust collecting vehicle equipped with the person recognition device according to any one of claims 1 to 3 , which is provided with an emergency stop device.

Images