JP2018039648A - Image display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image display system capable of securing in a short time visibility of a work vehicle comprising a stretchable boom on a side part of a cabin, in a travel time.SOLUTION: An image display system 10 which is mounted on a crane truck 1 as a work vehicle in which a boom 7 performing an expansion/shrinkage operation is provided on a left side of the vehicle with respect to a cabin 5 comprises: plural cameras 11 for acquiring peripheral images of the crane truck 1; an image display part 13 for performing image display on the basis of the image acquired by each camera 11; and a control part 12 for converting the images acquired by respective cameras 11 into images which are looked from upper vertical view points, connecting the images for forming an overhead image P of a peripheral part of the crane truck 1, then displaying the overhead image on the image display part 13. The control part 12 forms and displays an overhead image P2 in high speed travel, in which a left direction and a travel direction where the boom 7 of the crane truck 1 is positioned display a range from the peripheral part of the crane truck 1 to a horizon, in travel of the crane truck 1, as the overhead image P.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an image display system used for a work vehicle.

  Since the work vehicle is large and easily causes blind spots, it is proposed to mount an image display system that forms a bird's-eye view around the work vehicle and presents it to the operator (see, for example, Patent Document 1). ). In this conventional image display system, a plurality of cameras that capture the periphery of the work vehicle are provided, and an image captured by each camera is converted into an image looking down from an upper virtual viewpoint, and combined to obtain an overhead view of the periphery of the work vehicle. An image is formed.

  Further, in forming a bird's-eye view image, there is known one that displays a wider range by synthesizing a peripheral image in three directions on the front left and right of the vehicle and an image including the horizon (see, for example, Patent Document 2). .

  The bird's-eye view image as described above is normally used for checking the periphery of the vehicle during work or when moving backward, and when the vehicle is traveling or traveling at a high speed exceeding a predetermined vehicle speed, the display on the display unit itself is stopped. It is common. As described above, a vehicle that changes the display from a bird's-eye view image to a map image is known as one of vehicles that stop displaying the bird's-eye view image when traveling (see, for example, Patent Document 3).

Originally, work vehicles such as excavators are transported on trucks and the like and are not self-propelled, so display during travel is not considered.
On the other hand, some work vehicles can be self-propelled. In such an automatic work vehicle, it is common to ensure visibility during traveling by providing a plurality of mirrors such as rearview mirrors and side mirrors, and a camera for imaging the blind spot direction and displaying the captured image. It is.

JP 2011-71919 A JP 2014-123955 A JP 2008-2137744 A

By the way, as a work vehicle capable of self-propelling, a work vehicle (for example, a crane vehicle) in which a telescopic boom is provided in parallel in a cabin is known.
In a vehicle equipped with such a boom, the boom hinders visibility from the cabin. That is, since the boom is usually provided side by side with the cabin and extends forward from the cabin, the boom is obstructed by the boom from obliquely forward and sideways of the work vehicle.

However, as described above, the conventional image display system that displays a bird's-eye view image helps to ensure the visibility during the work, but the display is stopped during the travel, and the visibility during the travel is ensured. It wasn't something to do.
In addition, when a plurality of mirrors and cameras that reflect the direction of the blind spot due to the boom are provided, it takes time to check all of the plurality of mirrors and camera images, and the driving operation is complicated.

  The present invention has been made in view of the above circumstances, and provides an image display system capable of ensuring the visibility of a working vehicle having a telescopic boom on the side of a cabin during traveling in a short time. With the goal.

The image display system of the present invention is an image display system mounted on a work vehicle in which a boom that performs an expansion / contraction operation is arranged in parallel on either the left or right side of a cabin,
A plurality of cameras for obtaining a peripheral image of the work vehicle;
A display unit for displaying an image based on an image acquired by each camera;
A control unit that converts an image acquired by each camera into an image looking down from an upper virtual viewpoint and connects the images to form a bird's-eye view around the work vehicle and display the image on the display unit;
With
When the work vehicle travels, the control unit displays, as the overhead view image, a direction in which the boom is positioned with respect to the cabin in the left-right direction of the work vehicle and a travel direction from the periphery of the work vehicle to the horizon. An image display system that forms and displays a bird's-eye view image during traveling.
Moreover, the image display system of the present invention is an image display system mounted on a work vehicle in which a boom that performs an expansion / contraction operation is arranged on either the left or right side of the cabin, and acquires a peripheral image of the work vehicle. A plurality of cameras, a display unit that displays an image based on the images acquired by the cameras, and the periphery of the work vehicle by converting and connecting the images acquired by the cameras into an image looking down from an upper virtual viewpoint A control unit that forms a bird's-eye view image and displays the bird's-eye view image on the display unit, and the control unit displays the bird's-eye view image on the display unit when the work vehicle travels at a speed higher than a predetermined speed. This is an image display system.

  According to the image display system of the present invention, during driving, the driver can check the state of the work vehicle around the vehicle only by looking at the overhead view image on the display unit, and can check the situation around the work vehicle in a short time. .

It is explanatory drawing which shows typically a mode that the crane vehicle carrying the image display system of Embodiment 1 was seen from the side. It is explanatory drawing which shows a mode that the said crane vehicle was seen from upper direction. 1 is a block diagram illustrating a configuration of an image display system according to a first embodiment. It is a perspective view which shows the inside of the cabin of the said crane vehicle. It is a front view which shows an image display part when the surrounding bird's-eye view image which serves as a bird's-eye view image at the time of low-speed driving | running | working by the image display system of Embodiment 1 is displayed. It is a front view which shows the image display part when displaying the bird's-eye view image at the time of high-speed driving | running | working with the image display system of Embodiment 1. FIG. 3 is a front view showing an image display unit when a backward view overhead image is displayed by the image display system of the first embodiment. 4 is a flowchart illustrating a flow of processing of automatic display switching control by the image display system according to the first embodiment. It is explanatory drawing for demonstrating the problem at the time of the driving | running | working in the comparative example with embodiment. It is explanatory drawing for demonstrating the problem at the time of the driving | running | working in the comparative example with embodiment. 10 is a flowchart showing a flow of processing of automatic display switching control by the image display system according to the second embodiment.

The best mode for realizing the image display system of the present invention will be described below with reference to the drawings.
(Schematic configuration of crane truck)
First, the structure of the crane vehicle 1 as a work vehicle to which the image display system 10 of Embodiment 1 according to an embodiment of the image display system according to the present invention is applied will be described with reference to FIGS. 1 and 2.

  The crane vehicle 1 includes a traveling body (carrier) 2 and a swivel base 3. The traveling body 2 is a main body portion (vehicle body) of a vehicle having a traveling function, and includes a plurality of wheels W and a drive source (not shown) that drives the wheels W and the swivel base 3.

  Further, as shown in FIG. 2, the traveling body 2 has a substantially rectangular shape that is long in the front-rear direction (the arrow FR direction in FIG. 2 is the front of the vehicle and the arrow RR direction is the rear of the vehicle) in plan view. doing. As shown in FIG. 1, the traveling body 2 includes a pair of left and right outriggers 4 at the front and the rear. Each outrigger 4 can be extended and retracted to the left and right, and can be stably extended and grounded to stably support the traveling body 2 during work (work mode) using a boom 7 described later.

  As shown in FIGS. 1 and 2, the swivel base 3 is provided on the upper portion of the traveling body 2 so as to be turnable in the horizontal direction, and integrally includes a cabin 5 and a boom support 6. The cabin 5 is a passenger compartment for an operator to perform various operations, and is arranged to be biased to the right side in the vehicle width direction. In the cabin 5, an operation unit 14 and an image display unit 13 (see FIGS. 3 and 4) for an operator to perform various operations are provided. Note that various operations by the operation unit 14 include, for example, turning of the swivel base 3, raising and lowering and expanding / contracting of a boom 7, which will be described later, winding and unwinding of a winch provided on the boom support 6, Storage, engine start and stop, etc.

  1 and 2, the boom support 6 is configured such that the base end portion of the boom 7 is attached via a boom root fulcrum pin (not shown), and the boom 7 can be raised and lowered around the boom root fulcrum pin. To do. Further, the boom support 6 is provided with a hoisting cylinder (not shown) between the boom 7 and the boom 7 is raised and lowered by extending and retracting the hoisting cylinder.

  The boom 7 is provided on the left side of the vehicle with respect to the cabin 5 in the swivel base 3 and extends in the vehicle front-rear direction as shown in FIGS. And in Embodiment 1, as shown in FIG. 1, the boom 7 is arrange | positioned substantially horizontally at the time of non-use, such as the time of driving | running | working. In addition, the boom 7 is good also as what is called a slant boom arrange | positioned with the front-end | tip falling.

  Further, as is well known, the boom 7 has a proximal boom portion, an intermediate boom portion, and a distal end boom portion that are connected to each other by an expansion / contraction cylinder, and the intermediate boom portion and the distal end boom portion are sequentially arranged in the proximal boom portion. The telescopic cylinders are telescopically expanded and contracted by being telescopically combined. The boom 7 is in a state in which the wire is hung around the sheave of the tip boom portion and the hook is suspended, and each boom portion is housed when not in use such as traveling. In the first embodiment, the boom 7 has a tip portion 7 a protruding forward from the traveling body 2 when not in use.

(Image display system configuration)
Next, the configuration of the image display system 10 according to the first embodiment will be described.
As shown in FIG. 3, the image display system 10 includes a front camera 11F, a rear camera 11B, a left camera 11L, a right camera 11R, a control unit 12, an image display unit 13, an operation unit 14, an information acquisition unit 15, and a storage. Part 16.

  In addition, about each camera 11F, 11B, 11L, and 11R, when not pointing the thing of a specific direction, it only describes with the camera 11. FIG. Moreover, as the camera 11, you may have a camera other than each camera 11 shown in FIG.

As shown in FIGS. 1 and 2, the front camera 11 </ b> F is provided at the front end portion (front end portion excluding the boom 7) of the traveling body 2, and displays a region in front of the vehicle including the front end portion of the traveling body 2 over the horizon. Shoot as a forward image (Pa).
The rear camera 11B is provided at the rear end portion of the traveling body 2, and captures a rear region including the rear end portion of the traveling body 2 as a rear image (Pb) including the horizon.

The left camera 11L is provided at the left end of the swivel base 3 (the outer plate portion on the left side of the boom support 6), and a left image (Pc) including a left side region including the left end part of the swivel base 3 up to the horizon. )
The right camera 11R is provided at the right end of the swivel base 3 (the outer plate portion on the right side of the cabin 5), and a right image (Pd) including a right side region including the right end part of the swivel base 3 up to the horizon. Shoot as.

  Each camera 11 is, for example, a wide-angle camera having an angle of view of approximately 180 degrees in order to obtain a continuous image of the periphery of the traveling body 2 in the crane vehicle 1 over the entire circumference. The peripheral image of the traveling body 2 is an image including the ground surrounding the traveling body 2 when viewed from above, and a predetermined distance from a position adjacent to the traveling body 2 (for example, several meters of about 2 to 5 m). It is an image of the area up to.

  In addition, as long as these cameras 11 can acquire the image of the periphery of the traveling body 2 seamlessly over the entire circumference, the number of cameras 11 to be installed and the installation positions may be set as appropriate. It is not limited to the number and position.

  The control unit 12 is a microcomputer having a storage unit (built-in memory 12a) and a calculation unit, and is provided in the cabin 5 in the first embodiment. The control unit 12 controls the operations of the cameras 11, the image display unit 13, the operation unit 14, the information acquisition unit 15, and the storage unit 16 based on a program stored in the storage unit 16 or the built-in built-in memory 12 a. And information is appropriately acquired from each camera 11, the operation unit 14, and the information acquisition unit 15. In addition, the vehicle speed V detected by a vehicle speed sensor (not shown) etc. is input into the control part 12 as information used for the automatic display switching control mentioned later.

  And the control part 12 produces | generates the overhead image P based on the signal from each camera 11, the display process which displays the produced overhead image P (refer FIGS. 5-7) on the image display part 13, Detection / judgment processing of operations performed on the operation unit 14, display processing of various information acquired by the information acquisition unit 15, and the like are performed. In addition, as the bird's-eye view image P, the following three types of bird's-eye view images (peripheral bird's-eye view image P1, high-speed traveling bird's-eye view image P2 and reverse view bird's-eye view image P3) are formed. This is referred to as an “overhead view image”, and the reference numeral is simply “P”.

  Moreover, as a display in the image display part 13 by the control part 12, a camera image, the operation state of the crane vehicle 1, etc. other than the bird's-eye view image P can be displayed. In addition, as the display of the operation state of the crane vehicle 1, the turning state of the swivel base 3, the rising and falling state of the boom 7, the retracted state of the winch, the winding and unwinding state of the winch, the extension of each outrigger 4, the storage state, etc. are displayed. can do.

  Further, the control unit 12 outputs the bird's-eye view image P (its image data) generated by the image processing unit 17 to the image display unit 13 for display on the image display unit 13, and appropriately stores the bird's-eye view image P. To store. In the control unit 12, operation information (data) obtained in accordance with the operation of the operation unit 14 and various information (data) acquired by the information acquisition unit 15 are input.

  The image display unit 13 can display a bird's-eye view image P and various types of information in the crane vehicle 1, and a liquid crystal display or the like is used. The image display unit 13 includes a cabin 5 of the swivel base 3 as shown in FIG. Is provided inside.

As shown in FIG. 5, the image display unit 13 is divided into an upper warning display area A1, an intermediate camera image display area A2, and a lower switch area A3 in the vertical direction.
In the warning display area A1, various warning marks and the like are displayed.
The camera image display area A2 includes the above-described bird's-eye view image P, and displays camera images and images such as operation states and operation states.
In the switch area A3, various operation switches with a touch panel function are displayed, and a selection operation thereof can be performed.

  In addition, operation information of the operation unit 14 including operation information of various icons in the switch area A3 is output to the control unit 12. Furthermore, the operation unit 14 can perform an operation for switching an image to be displayed on the image display unit 13 and various setting operations in the image display system 10 or the crane vehicle 1.

  The information acquisition unit 15 acquires various types of operation information related to the crane vehicle 1 and outputs each type of operation information (data) to the control unit 12. The operation information includes the vehicle speed. In addition, for example, a traveling mode in which the boom 7 is housed and the swivel 3 is in a predetermined posture with respect to the traveling body 2 or a working mode in which the boom 7 is used. Mode information indicating whether or not, the turning angle of the swivel base 3 (boom 7), and the posture information indicating the undulation angle and length of the boom 7 are included.

(Overhead view)
Next, the overhead image P will be described.
The process of generating the overhead image P (see FIGS. 5 to 7) from the image (image data) acquired by each camera 11 described above is executed in the image processing unit 17.
A process for generating the overhead image P in the image processing unit 17 will be briefly described. First, the image processing unit 17 performs distortion correction processing for correcting distortion due to a lens by multiplying a coordinate value of an input pixel by a coefficient based on a lens distortion coefficient, an aspect ratio, or the like and converting the result to a coordinate value of an output pixel. Further, the image processing unit 17 multiplies the coordinate value of the input pixel by various coefficients based on the camera mounting angle and the like to form all the coordinate values of the output pixel, so that from the virtual viewpoint set above the crane vehicle 1. A bird's-eye view conversion process for converting into a looked down image (individual overhead view image) is performed.

  Further, the image processing unit 17 sets the brightness of the corresponding coordinate values as adjacent images from the cameras 11 that have performed the above-described processes while eliminating the uncomfortable feeling of the joints using linear interpolation or the like. An image synthesis process is performed to connect and generate a bird's-eye view image P (see FIGS. 5 to 7). Since this camera-overlaid image P is provided with each camera 11 as described above, it becomes an image around the traveling body 2 in the crane vehicle 1 and image information of a region where the traveling body 2 itself exists is missing. Therefore, this missing portion is set to, for example, a pixel value of zero (black display). In addition, as long as the image processing unit 17 generates a bird's-eye view image P (image data thereof) as a generation process, these processes may be performed at the same time, or other contents may be processed. It is not limited to each process of 1.

Then, the image processing unit 17 superimposes a work vehicle sign M that superimposes and represents the crane vehicle 1 in a simulated manner, as shown in FIGS. I do. The work vehicle sign M is a visual representation of the position and size of the crane vehicle 1 itself as a work vehicle in the overhead view image P, and a swivel 3 including a boom 7 and the like is provided on at least the traveling body 2. It is possible to grasp the situation. As the work vehicle sign M, an actual overhead view of the crane vehicle 1 may be used, or a design showing the overhead view of the crane vehicle 1 may be used.
At this time, the tip end portion 7a may be displayed transparently.

(Three types of overhead images)
In the first embodiment, as the bird's-eye view image P, there are three types of bird's-eye views: a peripheral bird's-eye view image P1 shown in FIG. 5, a high-speed traveling bird's-eye view image P2 shown in FIG. Images P1, P2, and P3 are formed. Each of these overhead images P1, P2, P3 is displayed in the camera image display area A2 of the image display unit 13 described above.

  The surrounding bird's-eye view image P <b> 1 is an image only around the crane vehicle 1. That is, the surrounding bird's-eye view image P1 is, for example, several meters (for example, about 2 to 3 m or more and about 10 m or less) from the crane vehicle 1 in each of the forward direction, the rear direction, the left direction, and the right direction of the crane vehicle 1. It forms with the image of the range. Further, in the display area R1 of the peripheral bird's-eye view image P1 in the image display unit 13, as shown in FIG. 5, the upper display area Pa1 and the lower display area Pb1 indicating the front and rear of the vehicle are substantially symmetrical with respect to the work vehicle sign M. In addition to the display, the left display area Pc1 and the right display area Pd1 indicating the left and right of the vehicle are displayed substantially symmetrically. In addition, in the surrounding bird's-eye view image P1, a line WL indicates a line that exists along the left and right sides of the vehicle, such as a white line that delimits a driving lane on the road.

  Since each camera 11 uses a wide-angle camera, the captured image data of any camera 11 includes image data in the range from the vehicle periphery to the horizon, and in the height direction. Is reflected in the sky. When generating the surrounding bird's-eye view image P1, only the image data in the range close to the crane vehicle 1 is used among the image data obtained by capturing a wide range in this way.

  In the high-speed driving bird's-eye view image P2 shown in FIG. 6, as shown in the drawing, the upper display area Pa2 for displaying the front of the vehicle, which is the traveling direction, is set wider than the lower display area Pb2 for displaying the rear of the vehicle. Thus, the left display area Pc2 for displaying the left side of the vehicle, which is the direction in which the boom 7 exists with respect to the cabin 5, is set wider than the right display area Pd2. Accordingly, the work vehicle sign M is displayed on the right side in the left-right direction and on the lower side in the vertical direction according to the arrangement of the display areas Pa2-Pd2 of the overhead image P2 during high-speed traveling.

In this case, in the overhead image P2 during high-speed traveling, the lower display area Pb2 and the right display area Pd2 are image data in a range that is a peripheral image of the crane 1 and that is narrower than the range displayed in the peripheral overhead image P1. Is used to form an overhead image.
That is, in the first embodiment, the right display area Pd2 displays a ground image in the range of 1 m or more from the crane vehicle 1, and the lower display area Pb2 displays a ground image in the range of 5 m or more from the crane vehicle 1. I tried to do it.

  On the other hand, in the upper display area Pa2 displaying the front of the vehicle in the traveling direction and the left display area Pc2 on the boom 7 side, a ground image from the vehicle periphery to the horizon is displayed, and several meters (in the height direction from the ground) For example, it displays up to a range of 5 m) or more. That is, in the left display area Pc2, the left-side image of the crane vehicle 1 imaged by the left camera 11L includes a range from the vehicle periphery to the horizon, and a range of 5 m or more in the height direction. Is used to form a bird's-eye view image P2 during high-speed traveling. Similarly, in the upper display area Pa2, the ground image among the images ahead of the crane vehicle 1 captured by the front camera 11F includes an area including the horizon from the periphery of the vehicle, and an image having a range of 5 m or more in the height direction. A bird's-eye view image P2 during high-speed traveling is formed using data.

  In the backward bird's-eye view image P3 shown in FIG. 7, as shown in the drawing, the lower display area Pb3 that displays the rear of the vehicle that is the traveling direction is set wider than the upper display area Pa3 that displays the front of the vehicle, and the left display area Pc3 and the right display area Pd3 are displayed symmetrically.

Then, in the backward bird's-eye view image P3, an image from the vehicle periphery to the horizon is displayed in the lower display area Pb3 that displays the vehicle rear that is the traveling direction. On the other hand, in the upper display area Pa3, the left display area Pc3, and the right display area Pd3 other than that, an image around the crane vehicle 1 (for example, a range from the crane vehicle 1 to several m or more) is displayed. Here, in the lower display area Pb3, the backward bird's-eye view image P3 is formed using image data in the range from the vehicle periphery to the horizon among the images behind the crane vehicle 1 captured by the rear camera 11B.
The work vehicle sign M is displayed at the center in the left-right direction and at the upper side in the up-down direction according to the arrangement of the display areas Pa3 to Pd3 of the bird's eye view image P3 when reversing.

(Automatic switching display control by the control unit)
Next, automatic display switching control executed by the control unit 12 during traveling of the crane vehicle 1 will be described.
As described above, the control unit 12 displays the bird's-eye view image P on the image display unit 13, but in the automatic display switching control, the surrounding bird's-eye view image P1, the high-speed running bird's-eye view image P2, and the backward view bird's-eye view. The display of the image P3 is switched. When the display switching operation is performed manually, the automatic display switching control may be canceled and the display based on the manual operation may be performed, or the display area by the manual operation and the display based on the manual operation may be performed. The area may be different.

Hereinafter, the flow of processing in this automatic display switching control will be described based on the flowchart of FIG.
First, in the first step S101, it is determined whether or not the travel mode is selected. In the travel mode, the process proceeds to step S102, and in the non-travel mode, the process proceeds to step S106. The traveling mode indicates a state in which the crane vehicle 1 is traveling, and whether or not the traveling mode is in the traveling mode can be determined based on, for example, the position of the shift lever of the operation unit 14. Further, the non-running mode may include, for example, during work.

  In step S102, which is proceeded when it is determined that the travel mode is determined in step S101, it is determined whether or not the travel is forward (reverse). When the travel is forward, the process proceeds to step S103, and when the travel is not forward (reverse), the step is performed. The process proceeds to S105.

  In step S103, which proceeds when the vehicle moves forward in step S102, it is determined whether or not the vehicle speed V is equal to or higher than a preset threshold value Vlim. This threshold value Vlim is a value for determining whether or not the crane vehicle 1 is traveling at a high speed, and for example, values of about several km / h, tens of km / h, and tens of km / h are used. it can. This threshold value Vlim is used to distinguish the vehicle speed V from a speed range in which a sense of distance around the vehicle is important and a speed range in which a wide range of field of view in the front and left directions of the vehicle is required. It is a value set in advance based on operability and the like.

  Then, in step S103, the process proceeds to step S104 when the vehicle speed is higher than Vlim and the vehicle proceeds to step S104. When the vehicle speed is lower than Vlim and the vehicle proceeds to step S106, the process proceeds to step S106.

In step S104, which proceeds when it is determined that the vehicle is traveling at a high speed in step S103, the bird's eye view image P2 and the front camera image FC during high speed traveling are displayed.
That is, as shown in FIG. 6, the camera image display area A2 of the image display unit 13 is divided into right and left, the high-speed driving overhead image P2 is displayed in the left area, and the front camera 11F images the right area. The front camera image FC is displayed. In the first embodiment, the right region for displaying the front camera image is set wider than the left region for displaying the overhead image P2 during high-speed driving.

  On the other hand, in step S106 which proceeds when it is determined in step S103 that the vehicle speed V is during low-speed forward traveling less than the threshold Vlim, as shown in FIG. 5, the surrounding overhead image P1 is displayed in the camera image display area A2 of the image display unit 13. indicate.

Further, in step S105, which proceeds when it is determined that the vehicle is not moving forward (backward) in step S102 of FIG. 8, the backward overhead image P3 and the rear camera image RC are displayed. That is, as shown in FIG. 7, the camera image display area A2 of the image display unit 13 is divided into left and right, the backward view overhead image P3 is displayed in the left area, and the rear camera 11B takes an image in the right area. The rear camera image RC is displayed. In this case, the right area for displaying the rear camera image is set wider than the left area for displaying the backward view overhead image P3.
Note that after executing any of the processes in steps S104 to S106, the process from the start is repeated, and this process is executed at a predetermined cycle.

(Operation of Embodiment 1)
Next, the operation of the image display system of Embodiment 1 will be described.
(During low speed forward travel)
When traveling at a low speed, as shown in FIG. 5, the surrounding bird's-eye view image P <b> 1 is displayed in the camera image display area A <b> 2 of the image display unit 13 (based on the processing of steps S <b> 101 → S <b> 102 → S <b> 103 → S <b> 106).

  When traveling at a low speed, visibility around the vehicle and a sense of distance are important. That is, in the crane vehicle 1, it is particularly necessary to pay attention to interference between the tip of the boom 7 and an object around the vehicle. For this reason, the visibility of the crane vehicle 1 around the vehicle and the sense of distance between the crane vehicle 1 and the surrounding objects are important. Therefore, as shown in FIG. 5, by displaying the four circumferences of the crane vehicle 1 substantially uniformly by the surrounding overhead image P <b> 1, attention can be paid over the entire circumference of the crane vehicle 1, and the crane vehicle It is easy to grasp the sense of distance between 1 and surrounding objects.

  In addition, during work that is not being performed, similarly, the surroundings of the crane vehicle 1 can be paid attention by displaying the four circumferences of the crane vehicle 1 substantially equally by using the surrounding bird's-eye view image P1. It is easy to get a sense of distance between 7 and surrounding objects.

(During high-speed forward travel)
During high-speed forward travel, as shown in FIG. 6, the high-speed travel overhead image P2 and the image of the front camera 11F are displayed in parallel (based on the processing of steps S101 → S102 → S103 → S104).

  During high-speed forward traveling, it is necessary to quickly recognize an object that is relatively close to the crane vehicle 1 from a distance in the traveling direction (front). In addition, an object approaching from the diagonally forward and left side of the vehicle that is difficult to see behind the boom 7 can be recognized directly from the cabin 5 or indirectly through a mirror or the like. , Driving safety is increased.

  Therefore, as shown in FIG. 6, the bird's-eye view image P <b> 2 during high-speed traveling is displayed on the image display unit 13 and displayed up to the horizontal line in the upper display area Pa <b> 2 and the left display area Pc <b> 2. An approaching object can be recognized before it is visually recognized. In addition, in the upper display area Pa2 and the left display area Pc2 that display up to the horizontal line, it is possible to recognize the approaching object earlier than in the case where only the peripheral image is displayed.

  Further, for the front, which is the traveling direction of the crane vehicle 1, a front camera image FC is displayed in addition to the overhead image P2 during high-speed traveling. The front camera image FC is displayed up to the horizon in front of the vehicle and is displayed larger than the overhead image P2 during high-speed traveling. For this reason, it is possible to recognize an approaching object from the front of the vehicle even earlier than when only the bird's-eye view image P2 is displayed during high-speed driving.

Here, based on FIG. 9A and FIG. 9B, the blind spot by the boom 7 in the comparative example which does not display the high-speed overhead image P2 will be described.
As in the first embodiment, in the crane vehicle 1 in which the boom 7 is provided side by side on the left side of the cabin 5, the boom 7 obstructs the oblique left front and left side views from the cabin 5. In particular, as shown in FIG. 9A, when traveling on a road RD that curves to the left, the area behind the boom 7 in the traveling direction (road RD) becomes wider than when traveling straight. For this reason, the vehicle MV1 parked on the left side of the road RD, the vehicle MV2 entering the road RD from the side road, and the like are behind the boom 7, and when viewed from the cabin 5, they come close to them and appear from behind the boom 7. It is difficult to recognize.

  Even if only the front camera image FC is displayed on the image display unit 13, the forward direction of the crane vehicle 1 and the direction of the road RD change from moment to moment on the left curve. There is a possibility that the vehicles MV1 and MV2 on the left side are not reflected in the front camera image FC. In particular, since the vehicle MV2 entering the road RD is located further left than the traveling direction, the vehicle MV2 may not be recognized without being reflected in the front camera image FC.

  Alternatively, even if only the surrounding bird's-eye view image P1 is displayed on the image display unit 13, if the traveling speed is high, these vehicles MV1 and MV2 are within the range (several meters) of the surrounding bird's-eye view image P1. Until it approaches, it cannot be recognized and it is difficult to recognize early.

  Furthermore, as shown in FIG. 9B, the vehicle MV3 that overtakes the crane vehicle 1 from the rear is normally confirmed by the rearview mirror, but it is recognized because the main viewing direction is the front that is the traveling direction. It tends to be late.

  On the other hand, in the first embodiment, during high-speed forward traveling, as shown in FIG. 6, the high-speed traveling overhead image P2 and the front camera image FC are displayed in parallel. In this high-speed traveling bird's-eye view image P2, the vehicle front and left sides are displayed up to the horizon, so even if the road RD is curved to the left and is behind the boom 7 as shown in FIG. Both vehicles MV1, MV2 are displayed in the image P2. Therefore, it becomes possible to recognize these vehicles MV1 and MV2 at an early stage.

  Similarly, in the high-speed overhead image P2, the left side is displayed up to the horizon. Therefore, as shown in FIG. 9B, the vehicle MV3 that overtakes from behind is also displayed in the high-speed overhead image P2 before being lined with the crane vehicle 1. Is displayed. Therefore, the driver can recognize the vehicle MV3 at an early stage only by checking the image display unit 13 without looking at the rearview mirror.

(During reverse travel)
During reverse travel, as shown in FIG. 7, the backward overhead image P3 and the captured image of the rear camera 11B are displayed side by side (based on the processing of steps S101 → S102 → S105).

  When traveling backward, visibility and a sense of distance around the vehicle are important as in low-speed forward traveling. That is, when reversing, visibility in the traveling direction is poor, and it is necessary to pay attention to interference between the tip of the boom 7 and objects around the vehicle. Therefore, a sense of distance between the crane vehicle 1 and surrounding objects is important. It is. Therefore, as shown in FIG. 7, the sense of distance between the crane vehicle 1 and the surrounding object can be recognized by displaying the periphery of the crane vehicle 1 around the four sides by the backward view overhead image P3. Furthermore, about the back which is the advancing direction of the crane vehicle 1, the object which approaches relatively in the advancing direction can be recognized at an early stage by displaying from the vehicle periphery to the horizon.

  Moreover, for the rear, which is the traveling direction of the crane vehicle 1, the rear camera image is displayed side by side in addition to the backward overhead image P <b> 3, and the rear camera image is displayed larger than the backward overhead image P <b> 3. It is possible to recognize an approaching object.

(Effect of embodiment)
The effects of the image display system of Embodiment 1 are listed below.
1) The image display system of Embodiment 1
An image display system 10 mounted on a crane vehicle 1 as a work vehicle in which a boom 7 that performs an expansion and contraction operation is arranged on the left side of the vehicle with respect to a cabin 5,
A plurality of cameras 11 for acquiring a peripheral image of the crane vehicle 1;
An image display unit 13 for displaying an image based on an image acquired by each camera 11,
A control unit 12 that converts an image acquired by each camera 11 into an image looking down from an upper virtual viewpoint and connects the images to form an overhead image P around the crane vehicle 1 and display the image on the image display unit 13;
With
When the crane 1 is traveling, the control unit 12 displays, as the overhead view image P, the left direction and the traveling direction in which the boom 7 of the crane vehicle 1 is located, from the periphery of the crane vehicle 1 to the horizon. An overhead image P2 is formed and displayed.
Accordingly, during traveling, the driver can check the horizon in the direction behind the boom 7 in addition to the four-round state of the crane 1 only by looking at the high-speed traveling overhead image P2 of the image display unit 13. .
Therefore, it is possible to reliably confirm the situation around the crane vehicle 1 and the obliquely forward and side conditions behind the boom 7 in a short time.

2) The image display system of Embodiment 1
When the vehicle 12 travels at a low speed where the vehicle speed V is less than the threshold Vlim, the image display system according to the first embodiment forms and displays a surrounding bird's-eye view image P1 that displays only the surroundings. A high-speed traveling overhead image P2 is formed and displayed.
Therefore, when traveling at a low speed, it is possible to recognize a sense of distance from the surroundings of the crane vehicle 1 and to prevent interference between an object around the vehicle and the vehicle body or the boom 7.
On the other hand, when traveling at high speed, the crane 4 can check the four-round state, and the direction behind the boom 7 (front and left) can be confirmed up to the horizon, quickly recognizing an approaching object in a short time. can do.

3) The image display system of Embodiment 1
The control unit 12 forms and displays an overhead image P2 during high-speed traveling when the vehicle is traveling forward, displays the traveling direction to the horizon during backward traveling, and displays the surroundings of the crane vehicle 1 in other directions. An image display system characterized by forming and displaying an overhead image P3.
Therefore, when reversing, the distance to the periphery of the crane vehicle 1 is reliably grasped, and the vehicle rear in the traveling direction can be confirmed up to the horizon, so that an approaching object in the traveling direction can be reliably confirmed in a short time. .

4) The image display system of Embodiment 1
The control unit 12 is characterized in that a camera image in the traveling direction is displayed on the image display unit 13 in parallel with the overhead image P2 during high-speed traveling and the overhead image P3 during backward traveling.
Therefore, an approaching object in the traveling direction can be recognized more reliably at an early stage.

5) The image display system of Embodiment 1
When displaying the overhead view image P2 during high-speed traveling, the control unit 12 displays the upper display area Pa2 that displays the traveling direction and the range of the horizon, and the vehicle left direction that is the direction in which the boom 7 is provided and the range of the horizon. The left display area Pc2 that displays up to is displayed wider than the lower display area Pb2 that displays the rear of the vehicle and the right display area Pd2 that displays the right direction of the vehicle.
Accordingly, in the upper display area Pa2 and the left display area Pc2, an area for displaying from the periphery of the crane vehicle 1 to the horizon is secured, and the upper display area Pa2, the left display area Pc2, and the lower display area Pb2, the symmetric position thereof, Compared to the case where the display area Pd2 is displayed with substantially the same area, a wide range up to the horizon can be displayed without a sense of incongruity.

6) The image display system of Embodiment 1
The control unit 12 displays a front camera image FC including the vicinity of the crane vehicle 1 in front of the vehicle imaged by the front camera 11F to the horizon in parallel with the overhead image P2 during high-speed traveling. .
Accordingly, the traveling direction of the vehicle can be confirmed by the front camera image FC in addition to the overhead view image P2 during high speed traveling, and the front camera image FC displays the range up to the horizon, and therefore approaches the crane vehicle 1. An object can be recognized early.

7) The image display system of Embodiment 1
The controller 12 displays a rear camera image RC including the vicinity of the crane vehicle 1 behind the vehicle captured by the rear camera 11B to the horizon in parallel with the backward overhead image P3 during backward traveling.
Therefore, the vehicle traveling direction can be confirmed by the rear camera image RC in addition to the backward view overhead image P3, and the rear camera image RC displays the range up to the horizon. Can be recognized early.

(Other embodiments)
Next, an image display system according to another embodiment will be described.
Note that in the description of other embodiments, components that are the same as those in the other embodiments are denoted by the same reference numerals as those of the present embodiment, and description thereof is omitted. Only differences from the present embodiment will be described.

(Embodiment 2)
The image display system of the second embodiment is an example in which the most common peripheral bird's-eye view image P1 as a bird's-eye view image is displayed during forward travel, reverse travel, and non-travel.

  FIG. 10 is a flowchart showing a flow of processing of automatic display switching control of the image display system according to the second embodiment. In the flowchart, the same processes as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted.

  In the second embodiment, in step S204 that proceeds when determining whether or not the vehicle is traveling forward in step S102 that determines whether or not the vehicle is traveling forward, the peripheral overhead image P1 and the front camera image FC are displayed side by side on the image display unit 13 in parallel. . Further, in the second embodiment, during forward traveling, regardless of the vehicle speed V, the parallel display of the surrounding overhead image P1 and the front camera image FC is maintained based on the processing in step S204.

  On the other hand, in step S205 that proceeds when it is determined whether the vehicle is traveling forward or not in step S102 that determines whether or not the vehicle is traveling forward, the image display unit 13 displays the surrounding bird's-eye view image P1 and the rear camera image RC side by side in parallel. To do.

The image display apparatus according to the second embodiment described above is
It is an image display system mounted on a crane vehicle 1 as a work vehicle in which a boom 7 that performs an expansion / contraction operation is arranged on the left side with respect to a cabin 5,
A plurality of cameras 11 for acquiring a peripheral image of the crane vehicle 1;
An image display unit 13 for displaying an image based on an image acquired by each camera 11,
An image acquired by each camera 11 is converted into an image looking down from an upper virtual viewpoint and connected to form a peripheral bird's-eye view image P1 that is a bird's-eye view around the crane vehicle 1 and displayed on the image display unit 13. When,
With
The control part 12 displays the surrounding bird's-eye view image P1 on the image display part 13 at the time of high-speed driving | running | working of the crane vehicle 1 or more than the predetermined speed, It is characterized by the above-mentioned.

Therefore, the driver can confirm the state of the four rounds of the crane vehicle 1 only by looking at the surrounding bird's-eye view image P1 of the image display unit 13 during traveling.
Therefore, the situation around the crane vehicle 1 can be confirmed in a short time, and obstacles and the like can be confirmed early.

  As described above, the image display system of the present invention has been described based on the embodiment. However, the specific configuration is not limited to the embodiment, and a design change, addition, or the like is possible without departing from the gist of the present invention. Is acceptable.

For example, in the first embodiment, the peripheral image is displayed during low-speed travel, but the present invention is not limited to this, and an overhead image during high-speed travel may be displayed during low-speed travel. In the first embodiment, an example is shown in which only the surrounding bird's-eye view image is displayed during low-speed traveling. However, the present invention is not limited to this, and the captured image of the camera in the traveling direction (front) is parallel to the bird's-eye view image even during low-speed traveling. May be displayed.
Further, in the embodiment, an example in which a camera image in the traveling direction is displayed in parallel with the overhead view image during forward traveling and backward traveling is shown, but the present invention is not limited to this, and only the overhead image may be displayed. Good.

In the first embodiment, the bird's-eye view image during high-speed driving shows an example in which the display area in the rear and right directions is displayed narrower than the front and left directions, but the display areas are set symmetrically in the vertical and horizontal directions. May be.
Even when reversing, the boom side (leftward direction) may be displayed up to the horizon.

1 Crane truck (work vehicle)
5 Cabin 7 Boom 10 Image display system 11B Rear camera 11F Front camera 11L Left camera 11R Right camera 12 Control unit 13 Image display unit FC Front camera image P1 Perspective bird's-eye view image P2 High-speed running bird's-eye view image P3 Backward view bird's-eye view RC Camera image

Claims (5)

An image display system mounted on a work vehicle in which a boom that performs expansion and contraction is mounted on either the left or right side of the cabin,
A plurality of cameras for obtaining a peripheral image of the work vehicle;
A display unit for displaying an image based on an image acquired by each camera;
A control unit that converts an image acquired by each camera into an image looking down from an upper virtual viewpoint and connects the images to form a bird's-eye view around the work vehicle and display the image on the display unit;
With
When the work vehicle travels, the control unit displays, as the overhead view image, a direction in which the boom is positioned with respect to the cabin in the left-right direction of the work vehicle and a travel direction from the periphery of the work vehicle to the horizon. An image display system for forming and displaying a bird's-eye view image during traveling. The image display system according to claim 1,
The control unit forms and displays a surrounding bird's-eye view image that displays only the periphery of the work vehicle when the traveling speed is lower than a predetermined speed, and displays the bird's-eye view when traveling at a high speed that is equal to or higher than the predetermined speed. An image display system for forming and displaying an image. The image display system according to claim 1 or 2,
The control unit forms and displays the bird's-eye view image during traveling forward, displays the traveling direction up to the horizon during backward traveling, and displays the surroundings of the work vehicle in other directions. An image display system for forming and displaying an image. In the image display system according to any one of claims 1 to 3,
The said control part displays the camera image of a running direction on the said display part in parallel with the said bird's-eye view image, The image display system characterized by the above-mentioned. An image display system mounted on a work vehicle in which a boom that performs expansion and contraction is mounted on either the left or right side of the cabin,
A plurality of cameras for obtaining a peripheral image of the work vehicle;
A display unit for displaying an image based on an image acquired by each camera;
A control unit that converts an image acquired by each camera into an image looking down from an upper virtual viewpoint and connects the images to form a bird's-eye view around the work vehicle and display the image on the display unit;
With
The said control part displays the said bird's-eye view image on the said display part at the time of high-speed driving | running | working more than the predetermined speed of the said working vehicle, The image display system characterized by the above-mentioned.