JP7119795B2 - Remote control system for forklift - Google Patents

Description

The present invention relates to a remote control system for forklifts.

In the device for monitoring the rear surroundings of a work vehicle disclosed in Patent Document 1, the turning center of the vehicle body is obtained based on the steering angle of the rear wheels, the traveling trajectories of the left and right rear wheels are calculated based on the turning center data, A bird's-eye view image having a rear image portion, a left side image portion, and a right side image portion arranged corresponding to the periphery of the vehicle body image is formed from the captured image data. Then, a composite image is created by superimposing the traveling trajectory on the bird's-eye view image, and the composite image is displayed as an enlarged image of the left and right rear wheels on a back-around monitor device arranged in the cockpit.

JP 2014-239357 A

By the way, in the remote control system for a forklift, when the technique of Patent Document 1 is used, interference with a structure (obstacle) is difficult to understand only by superimposing the traveling locus of the rear wheel at a position advanced by a predetermined distance.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a remote control system for a forklift that makes it easier to understand the relationship with an interfering object when the forklift is turning.

A remote control system for a forklift for solving the above problems includes a forklift equipped with a cargo handling device on the machine base and having a vehicle communication unit, and an operation device communication unit that performs wireless communication with the vehicle communication unit, and the forklift and a remote control device used to remotely control the traveling of the forklift and the cargo handling by the cargo handling device, the remote control system for a forklift comprising: a camera mounted on the forklift for imaging the surroundings of the forklift; A display unit provided in the remote control device for displaying an image captured by the camera, and a rear corner of the machine base opposite to the turning direction based on the current steering angle prior to turning the forklift. a trajectory superimposing unit that generates a predicted trajectory, superimposes it on the image captured by the camera, and causes the display unit to display the predicted trajectory.

According to this, prior to turning the forklift, a predicted trajectory of the rear corner of the machine base on the side opposite to the turning direction is generated based on the current steering angle, and is superimposed on the image captured by the camera and displayed on the display unit. Is displayed. Therefore, it is possible to make it easier to understand the relationship with the interfering object when the forklift is turning.

Further, in the forklift remote control system, the trajectory superimposing unit is configured, prior to turning of the forklift, based on the current steering angle, of the pair of left and right forks on the opposite side of the turning direction, or with the turning direction. It is preferable to further generate a predicted trajectory of the front corner of the pallet on the opposite side, superimpose it on the image captured by the camera, and display it on the display unit.

Further, in the forklift remote control system, when the pallet sensor detects the pallet on the fork, the trajectory superimposing unit predicts the front corner of the pallet opposite to the turning direction based on the current steering angle prior to turning the forklift. It is preferable to further generate a trajectory and superimpose it on the image captured by the camera and display it on the display unit.

Further, regarding the remote control system for a forklift, the forklift is a reach type forklift, and the trajectory superimposed portion is formed by a pair of left and right reach legs arranged on the front side of the machine base based on the current steering angle prior to turning of the forklift. Estimated trajectory of the front corner of the reach leg on the opposite side of the turning direction or the shaft center of the left and right front wheels provided on the pair of left and right reach legs arranged on the front side of the machine body on the opposite side to the turning direction is further generated and superimposed on the image captured by the camera and displayed on the display unit.

Further, in the remote control system for forklifts, the trajectory superimposing part is configured to cover an area sandwiched between the expected trajectory of the front corner of the pallet in the turning direction and the expected trajectory of the rear corner of the machine base on the opposite side to the turning direction, It is preferable to display it on the display unit so as to distinguish it from other areas.

In the remote control system for a forklift truck, the trajectory superimposing unit includes the expected trajectory of the front corner of the reach leg in the turning direction or the expected trajectory of the axis center of the front wheel in the turning direction, and the rear corner of the machine on the side opposite to the turning direction. It is preferable that the display unit displays the area sandwiched between the predicted trajectory of the part and the other areas so as to be distinguished from other areas.

Further, in the forklift remote control system, the forklift is a counter-type forklift, and prior to turning of the forklift, the trajectory superimposed portion is set to the opposite side of the turning direction of the left and right front wheels based on the current steering angle. It is preferable to further generate a predicted trajectory of the center of the shaft of the front wheel, superimpose it on the image captured by the camera, and display it on the display unit.

According to the present invention, it is possible to make it easier to understand the relationship with the interfering object when the forklift is turning.

FIG. 2 is a block diagram showing the electrical configuration of the forklift remote control system; The schematic side view which shows a reach-type forklift. BRIEF DESCRIPTION OF THE DRAWINGS The schematic perspective view which fracture|ruptures and shows a part of reach-type forklift. The top view which shows a reach-type forklift typically. 4 is a flow chart in the first embodiment; The top view which shows a reach-type forklift typically. The top view which shows a reach-type forklift typically. (a), (b) is a figure which shows the display content in a display part. 1A is a plan view schematically showing a reach-type forklift, FIG. 1B is a plan view schematically showing the reach-type forklift, and FIG. The flowchart in 2nd Embodiment. The top view which shows a reach-type forklift typically. The top view which shows a reach-type forklift typically. (a), (b), and (c) are diagrams showing contents displayed on a display unit. 1A is a plan view schematically showing a reach-type forklift, FIG. 1B is a plan view schematically showing the reach-type forklift, and FIG. FIG. 2 is a plan view schematically showing a reach-type forklift and its surroundings; FIG. 2 is a plan view schematically showing a reach-type forklift and its surroundings; The top view which shows typically the reach-type forklift in 3rd Embodiment, and its periphery. (a), (b) is a top view which shows typically the reach-type forklift truck in 3rd Embodiment. The top view which shows typically the reach-type forklift in 4th Embodiment. (a), (b), and (c) are diagrams showing contents displayed on a display unit. 1A is a plan view schematically showing a reach-type forklift, FIG. 1B is a plan view schematically showing the reach-type forklift, and FIG. FIG. 2 is a plan view schematically showing a reach-type forklift and its surroundings; FIG. 2 is a plan view schematically showing a reach-type forklift and its surroundings; The top view which shows typically the reach-type forklift and its periphery in 5th Embodiment. The top view which shows typically the reach-type forklift and its periphery in 5th Embodiment. The schematic side view which shows the counter-type forklift of example of another. The top view which shows a counter-type forklift typically.

(First embodiment)
An embodiment embodying the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the forklift remote control system 10 includes a reach-type forklift 20 and a remote control device 40 used to remotely control travel of the reach-type forklift 20 and cargo handling by the cargo handling device. . A reach-type forklift 20 is arranged at a work place. Then, using the remote control device 40, the reach-type forklift 20 in the workplace can be remotely controlled from the control room.
A reach-type forklift 20 is positioned at a place apart from pallets and the like in a work place. From this state, the operator remotely operates the reach-type forklift 20 to move the reach-type forklift 20 closer to the pallet or the like and insert the forks into the pallet holes.

As shown in FIGS. 2 and 3 , the reach-type forklift 20 has a machine base 21 . A pair of left and right reach legs 22a and 22b are arranged on the front side of the machine base 21, and the reach legs 22a and 22b extend forward. Specifically, the reach leg 22a is provided on the right side in the traveling direction, and the reach leg 22b is provided on the left side in the traveling direction. Front wheels 23a, 23b are arranged in front of the reach legs 22a, 22b. Specifically, the right front wheel 23a is provided on the right reach leg 22a in the traveling direction, and the left front wheel 23b is provided on the left reach leg 22b in the traveling direction. In this manner, a pair of left and right front wheels 23a and 23b are provided on the front side of the machine base 21. As shown in FIG.

Rear wheels 24 and caster wheels (auxiliary wheels) 25 are arranged at the rear of the machine base 21 . A rear wheel 24 is provided on the left side of the machine base 21 , and a caster wheel 25 is provided on the right side of the machine base 21 . The rear wheels 24 are driving and steering wheels.

As shown in FIG. 2 , the reach-type forklift 20 runs on three wheels, two front wheels 23 a and 23 b and one rear wheel 24 . A traveling motor 26 that serves as a drive source for the reach-type forklift 20 and a battery 27 that serves as a power source for the traveling motor 26 are mounted on the machine base 21 . Then, the rear wheels 24 are rotationally driven by the travel motor 26 .

The reach-type forklift 20 includes a cargo handling device 28 in front of the machine base 21 . The cargo handling device 28 includes a mast 29 that moves back and forth along each reach leg 22a, 22b by driving a reach cylinder (not shown). A pair of left and right forks 30 a and 30 b are provided in front of the mast 29 via a lift bracket 31 . The forks 30a, 30b move up and down along the mast 29.

The reach-type forklift 20 of the present embodiment is configured so that a driver can be seated and operated. Note that an unmanned reach-type forklift without a driver's seat may be used.
As shown in FIG. 3 , the reach-type forklift 20 has a standing-type driver's cab 32 at the rear of the machine base 21 . Steering tables 33 a and 33 b are provided in front and left of the driver's cab 32 . A steering table 33a positioned in front of the driver's cab 32 is provided with a direction lever 34 for driving the reach-type forklift 20 and a plurality of cargo handling levers 35 for operating the cargo handling device 28. As shown in FIG. The direction lever 34 is operated to rotate the rear wheels 24 to drive the vehicle. A steering table 33b located on the left side of the driver's cab 32 is provided with a steering wheel 36 for steering the rear wheels 24. As shown in FIG. A brake pedal 37 is provided on the floor of the cab 32 .

The driver's cab 32 is surrounded by two pillars 38 erected on the machine base 21 and a head guard 39 fixed to the upper ends of the pillars 38 .
As shown in FIG. 1, the reach-type forklift 20 includes, as the forklift-mounted equipment 50, a controller 51, a wireless unit 52 as a vehicle communication section, an image processing section 53, a wireless device 54 as a vehicle communication section, and a camera. 71,72,73.

The remote operation device 40 has a controller 61, an operation unit 62, a display unit (monitor) 63, and wireless devices 64 and 65 as operation device communication units. The remote control device 40 includes a controller 61 , an operation section 62 , and a display section (monitor) 63 as the control room side equipment 60 .

The radio 64 of the remote control device 40 is located at the workplace. Also, the wireless device 65 of the remote control device 40 is arranged in the workplace. A controller 61 placed in the operation room is connected to a wireless device 64 placed in the workshop via a wire L1. The controller 61 is connected to a wireless device 65 placed in the workplace via a wire L2.

In the workplace, the radio 64 of the remote controller 40 and the radio unit 52 of the forklift-mounted equipment 50 can communicate bidirectionally. In addition, wireless communication can be performed from the wireless device 54 of the equipment 50 mounted on the forklift to the wireless device 65 of the remote control device 40 in the workplace.

Thus, the reach forklift 20 has a radio unit 52 and a radio 54 and the remote controller 40 has radios 64 and 65 for wireless communication with the radio unit 52 and the radio 54 .

A controller 61 of the remote control device 40 is connected to an operation section 62 and a display section (monitor) 63 . The operation unit 62 is for remote control of the reach-type forklift 20 by the operator, and the contents of the operation of the reach-type forklift 20 by the operator (lift, reach, tilt operation command values, speed, acceleration, steering corner operation command value, etc.) is sent to the controller 61 . The controller 61 wirelessly transmits vehicle control signals such as lift, reach, and tilt operation command values and speed, acceleration, and steering angle operation command values to the wireless unit 52 of the forklift-mounted device 50 via the wireless device 64. do.

In the forklift-mounted equipment 50, the controller 51, the wireless unit 52, and the image processing section 53 are connected so as to be able to communicate with each other (for example, CAN communication). The controller 51 can drive travel system actuators (travel motor 26, steering motor (not shown), etc.) and cargo handling system actuators (lift cylinder, reach cylinder, tilt cylinder, etc. (not shown)) according to instructions from the remote control device 40 side.

The wireless unit 52 wirelessly transmits vehicle information such as vehicle speed of the reach-type forklift 20 and abnormality information (such as obstacle detection information) to the controller 61 via the wireless device 64 .
In FIG. 1 , a controller 61 can remotely control traveling of the reach-type forklift 20 and cargo handling by the cargo handling device 28 via the wireless device 64 , the wireless unit 52 and the controller 51 . In other words, remote operation can be performed by the operation unit 62 of the remote control device 40 in place of the operation units (the direction lever 34, the cargo handling lever 35, the handle 36, the brake pedal 37, etc.) in FIG.

In the remote control device 40 , when the operator performs a desired operation using the operation unit 62 , the operation content is sent to the reach-type forklift 20 via the wireless device 64 by the controller 61 . In the reach-type forklift 20, the wireless unit 52 receives the operation details from the remote control device 40, and the actuator section is driven by the controller 51 to perform a desired operation.

As shown in FIG. 4 , the reach-type forklift 20 has a right rear corner portion P1 and a left rear corner portion P2 on the machine base 21 .
As shown in FIGS. 2 and 4 , a camera 71 is attached to the front portion of the head guard 39 of the reach-type forklift 20 so as to face forward and downward. Specifically, the camera 71 captures an image of the floor in front of the reach-type forklift 20 in the traveling direction. A camera 72 is attached to the right rear portion of the head guard 39 of the reach-type forklift 20 so as to face downward, and the camera 72 images the surroundings of the reach-type forklift 20 . Specifically, the camera 72 takes an image of the vicinity of the right rear corner P1 of the machine base 21 from above. A camera 73 is attached to the left rear portion of the head guard 39 of the reach-type forklift 20 so as to face downward, and the camera 73 images the surroundings of the reach-type forklift 20 . Specifically, the camera 73 takes an image of the vicinity of the left rear corner P2 of the machine base 21 from above.

As shown in FIG. 1 , in reach-type forklift 20 , images captured by cameras 71 , 72 , and 73 are sent by controller 51 to remote controller 40 via image processor 53 and radio 54 . In the remote control device 40 , the camera image from the reach-type forklift 20 is received by the wireless device 65 and displayed on the display section 63 by the controller 61 . The display unit 63 is, for example, a desktop display.

The images captured by the cameras 71 , 72 and 73 are displayed on the display unit 63 provided in the remote control device 40 . The operator operates while viewing the images of the cameras 71 , 72 , 73 on the display unit 63 .

Next, the action will be described.
As shown in FIG. 5, in step S101, the controller 61 causes the rear corners P1 and P2 of the machine base 21 to move at the maximum steering wheel angle (in place turning) as shown in FIG. Circles C1 and C2 as expected trajectories to pass through are expressed in the world coordinate system. The right front wheel 23a is used as a reference for the turning radius when turning right. The left front wheel 23b is used as a reference for the turning radius when turning left. Further, the turning radius is maximum at the circle drawn by rear corners P1 and P2, which are the outermost rear parts of the machine base of the reach-type forklift.

5, the controller 61 detects the relative positions of the circles C1 and C2 of step S101 and the cameras 71, 72, and 73, and converts the circles C1 and C2 of step S101 into the world coordinate system as shown in FIG. Coordinate transformation from to the camera coordinate system. In step S103 of FIG. 5, the controller 61 coordinate-transforms the circles C1 and C2 of step S102 from the camera coordinate system to the monitor coordinate system. In step S104 of FIG. 5, the controller 61 superimposes the circles C1 and C2 of step S103 on the camera image, and displays the rear corners P1 and C2 of the machine base on the display unit 63 as shown in FIGS. Display around P2.

More specifically, when turning to the left, as shown in FIG. 9(a), a circle C1 through which the rear corner P1 of the machine base passes is expressed in the world coordinate system, and as shown in FIG. 9(b). , the relative positions of the circle C1 and the cameras 72 and 73 are detected, and the coordinates of the circle C1 are transformed from the world coordinate system to the camera coordinate system. Further, the circle C1 is coordinate-transformed from the camera coordinate system to the monitor coordinate system, superimposed on the camera image, and displayed on the display section 63 as shown in FIG. 9(c). That is, a circle C1 is generated and displayed as the predicted trajectory of the rear corner P1 of the machine base on the side opposite to the turning direction where there is a possibility of interference when turning left. This makes it easy for the operator to determine whether or not to interfere.

On the other hand, when turning to the right, the circle C2 through which the rear corner P2 of the machine base passes is expressed in the world coordinate system, the relative positions of the circle C2 and the cameras 72 and 73 are detected, and the circle C2 is detected from the world coordinate system by the cameras. Further, the circle C2 is coordinate-transformed from the camera coordinate system to the monitor coordinate system, and the circle C2 is superimposed on the camera image and displayed on the display unit 63 . That is, a circle C2 is generated and displayed as a predicted trajectory of the rear corner portion P2 of the machine base on the side opposite to the turning direction where there is a possibility of interference when turning to the right. This makes it easy for the operator to determine whether or not to interfere.

In this way, prior to turning of the reach-type forklift 20, the controller 61 sets circles (C1, C2 ). The controller 61 causes the display unit 63 to superimpose the images captured by the cameras 71 , 72 , and 73 on the images.

Specifically, prior to spot turning of the reach-type forklift 20 that turns at the maximum steering wheel angle, the controller 61 as the locus superimposing unit controls the rear corner of the machine base (P1, Circles (C1, C2) are generated as the predicted trajectory of P2) and superimposed on the images captured by the cameras 71, 72, 73 and displayed on the display unit 63. FIG.

A detailed description will be given below.
Circles C1 and C2 as predicted trajectories of the rear corners P1 and P2 of the machine base are superimposed on the camera image and displayed. The reach-type forklift 20 is often used in relatively narrow places because it is rear-wheel-steered and has a small turning radius. Therefore, if the turning radius is not correctly predicted and judged, there is a possibility of contacting surrounding objects during turning. In particular, when operating the reach-type forklift 20 by remote control, the operator must predict and judge the turning radius of the reach-type forklift 20 from the camera image, which makes it difficult to make a correct judgment compared to manned operation. . Therefore, when turning the reach-type forklift 20 at the maximum handle angle from the current position, that is, when performing so-called on-the-spot turning, the circles C1 and C2 through which the rear corners P1 and P2 of the machine base pass are superimposed on the camera image as a guide display. displayed.

In this way, when the reach type forklift is turned at the maximum handle angle from the current position, that is, when turning on the spot, the circles C1 and C2 are displayed as guides as expected trajectories of the rear corners P1 and P2 of the machine base. is superimposed on the camera image and displayed. Therefore, the circles C1 and C2 (turning radii) as the predicted trajectories of the rear corners P1 and P2 of the machine base can be easily recognized, and safety during turning by remote control is improved.

According to the above embodiment, the following effects can be obtained.
(1) The configuration of the forklift remote control system 10 includes a reach-type forklift 20 having a cargo handling device 28 on a machine base 21 and a wireless unit 52 and a wireless device 54 as vehicle communication units. It also has radio units 64 and 65 as operating device communication units that perform radio communication with the radio unit 52 as the vehicle communication unit and the radio unit 54, and remotely controls the travel of the reach-type forklift 20 and the cargo handling by the cargo handling device 28. A remote control device 40 is provided. Cameras 71, 72, 73 mounted on the reach-type forklift 20 for imaging the surroundings of the reach-type forklift 20, and a remote control device 40 provided for displaying images picked up by the cameras 71, 72, 73. A display unit 63 is provided. Prior to turning the reach-type forklift 20, circles (C1, C2) are generated as predicted trajectories of the rear corners (P1, P2) of the machine base on the opposite side to the turning direction based on the current steering angle, and the camera (71 , 72 and 73), and a controller 61 as a trajectory superimposing unit that superimposes the image on the display unit 63 and displays it. Therefore, when the reach-type forklift 20 turns, it is possible to make it easier to understand the relationship with interference objects (obstacles, etc.).

(2) The swing of the reach-type forklift 20 is spot swing. Therefore, since the circles C1 and C2 as the predicted trajectories of the rear corners P1 and P2 of the machine base are displayed prior to the on-the-spot turning, the relationship between the reach-type forklift 20 and the interfering object can be understood during the on-the-spot turning. can be made easier.

(Second embodiment)
Next, the second embodiment will be described, focusing on differences from the first embodiment.
As shown in FIG. 4, the reach-type forklift 20 has a tip portion P11 of the right fork 30a and a tip portion P12 of the left fork 30b.

As shown in FIG. 10, in step S201, when the controller 61 turns at the maximum steering wheel angle (when turning on the spot), the rear corners P1 and P2 of the machine base pass as shown in FIG. Circles C1 and C2 as predicted trajectories and circles C11 and C12 as predicted trajectories passed by the tips P11 and P12 of the forks are expressed in the world coordinate system. The right front wheel 23a is used as a reference for the turning radius when turning right. The left front wheel 23b is used as a reference for the turning radius when turning left. Also, the circles C11 and C12 through which the fork tips P11 and P12 pass change depending on the reach-in/out state (the position of the mast 29 in the longitudinal direction).

10, the controller 61 detects the relative positions of the circles C1, C2, C11, C12 of step S201 and the cameras 71, 72, 73 as shown in FIG. , C11 and C12 from the world coordinate system to the camera coordinate system. In step S203, the controller 61 coordinate-transforms the circles C1, C2, C11, and C12 in step S202 from the camera coordinate system to the monitor coordinate system. In step S204, the controller 61 superimposes the circles C1, C2, C11, and C12 of step S203 on the camera image, and displays them on the display unit 63 as shown in FIGS. The vicinity of the front and rear corners P1 and P2 of the machine base is displayed.

More specifically, when turning left, as shown in FIG. 14(a), a circle C1 through which the rear corner P1 of the machine base passes and a circle C11 through which the tip portion P11 of the fork passes are expressed in the world coordinate system. Then, as shown in FIG. 14B, the relative positions of the circles C1, C11 and the cameras 71, 72, 73 are detected, and the coordinates of the circles C1, C11 are transformed from the world coordinate system to the camera coordinate system. Further, the circles C1 and C11 are coordinate-transformed from the camera coordinate system to the monitor coordinate system, the circles C1 and C11 are superimposed on the camera image, and displayed on the display unit 63 as shown in FIG. 14(c). On the other hand, when turning to the right, the circles C2 and C12 through which the rear corner P2 of the machine base and the fork tip P12 pass are expressed in the world coordinate system, and the relative positions of the circles C2 and C12 and the cameras 71, 72, and 73 are expressed as follows. The coordinates of the circles C2 and C12 are transformed from the world coordinate system to the camera coordinate system. Furthermore, the circles C2 and C12 are coordinate-transformed from the camera coordinate system to the monitor coordinate system, and the circles C2 and C12 are superimposed on the camera image and displayed on the display unit 63 .

Guide display of the turning range of the machine base in this embodiment will be described with reference to FIGS. 15 and 16. FIG.
When turning the forklift at the maximum handle angle from the current position (when turning on the spot), the circles through which the rear corners P1 and P2 of the machine base and the fork tips P11 and P12 pass are superimposed on the camera image as a guide display. indicate. In other words, regarding the turning radius when turning left (based on the front left wheel) and the turning radius when turning right (based on the front right wheel), the turning radius is greatest at the rear corner P1, which is the outermost part of the rear part of the forklift platform. , P2 becomes a circle.

When the machine base is to be turned 360 degrees, a clearance from obstacles around the machine base is required corresponding to the turning radii of the rear corners P1 and P2 of the machine base. On the other hand, in other cases (for example, when turning the machine base by 90 degrees), it is not always necessary to provide a clearance corresponding to the turning radius of the rear corners P1 and P2 of the machine base. There is no problem if there is a clearance corresponding to the turning radius of the fork tips P11 and P12 in the area where the fork does not pass. Therefore, not only the circles through which the rear corners P1 and P2 of the machine base pass but also the circles through which the fork tip portions P11 and P12 pass are displayed as a guide.

As shown in FIG. 15, when turning left by 360 degrees, the turning radius (circle C1) of the rear corner P1 of the machine base is displayed, and the turning radius of the rear corner P1 of the machine base is displayed in all directions. of obstacle clearance is required.

As shown in FIG. 16, when turning left by 90 degrees, the turning radius (circle C1) of the rear corner portion P1 of the machine base and the turning radius (circle C11) of the fork tip portion P11 are displayed. In the area through which the rear corner P1 of the machine base passes, a clearance corresponding to the turning radius (circle C1) of the rear corner P1 of the machine base is required from surrounding obstacles. A clearance corresponding to the turning radius (circle C11) is sufficient.

In other words, when turning 90 degrees on the spot to face the pallet at the placement position, the maximum turning radius is at the rear corner P1 of the machine. A clearance corresponding to the turning radius (circle C1) of the rear corner P1 is required. On the other hand, in the area where the rear corner P1 of the machine base does not pass, it is sufficient to have a clearance corresponding to the turning radius (circle C11) of the fork tip portion P11. In this manner, the predicted turning trajectories (circles C1 and C11) of the rear corner portion P1 of the machine base and the front end portion P11 of the fork are displayed. By displaying the guide in this way, it is possible to easily determine whether or not it is possible to face the obstacle without interfering (contacting) it.

According to this embodiment, in addition to the above (1), the following effects can be obtained.
(3) Prior to turning of the reach-type forklift 20, the controller 61 as a trajectory superimposing unit controls the leading end portion (P11 , P12) are further generated and superimposed on the images captured by the cameras (71, 72, 73) and displayed on the display unit 63. FIG. Therefore, since the circles C11 and C12 are displayed as the predicted trajectories of the tips P11 and P12 of the forks 30a and 30b, it is possible to make it easier to understand the relationship with the interference object when the reach-type forklift 20 is turning. .

(Third embodiment)
Next, the third embodiment will be described with a focus on differences from the second embodiment.
In the present embodiment, as shown in FIG. 17, the controller 61, prior to turning of the reach-type forklift 20, controls a circle as the predicted trajectory of the rear corner P1 on the side opposite to the turning direction based on the current steering angle. A circle C51 is generated as an expected trajectory of C1 and the reach leg front corner P51 (or the center of the front wheel axle). Then, the controller 61 superimposes the images captured by the cameras 71, 72, and 73 on the display unit.

Here, in FIG. 18A, when the front wheels 23a and 23b do not protrude from the reach legs 22a and 22b, circles C51 and C52 are displayed as predicted turning trajectories of the front corners P51 and P52 of the reach legs. On the other hand, as shown in FIG. 18B, when the front wheels 23a and 23b protrude from the reach legs 22a and 22b, circles C61 and C62 are displayed as predicted turning trajectories of the front wheel axle centers P61 and P62.

Specifically, for example, as shown in FIG. 17, when turning 180 degrees on the spot to change direction, the turning radius is maximized at the rear corner P1 of the machine base. A circle C1 is displayed as a predicted turning trajectory. By displaying the guide in this way, it is possible to easily determine whether the direction can be changed without interfering (contacting) with the obstacle.

According to this embodiment, in addition to the above (1), the following effects can be obtained.
(4) Prior to turning of the reach-type forklift 20, the controller 61 as a trajectory superimposing unit adjusts one of the pair of left and right reach legs 22a and 22b arranged on the front side of the machine base based on the current steering angle. circles (C51, C52) as expected trajectories of the front corners (P51, P52) of the reach leg, or the left and right front wheels 23a, 23b provided on the pair of left and right reach legs 22a, 22b arranged on the front side of the machine Circles (C61, C62) are further generated as predicted trajectories of the front wheel shaft centers (P61, P62) on the opposite side of the turning direction, and are superimposed on the images captured by the cameras (71, 72, 73). Displayed on the display unit 63 . Therefore, the predicted trajectory of the reach legs 22a, 22b or the predicted trajectory of the axis center of the front wheels 23a, 23b is displayed.

(Fourth embodiment)
Next, the fourth embodiment will be described, focusing on differences from the second embodiment.
As shown in FIG. 2, the lift bracket 31 is provided with a pallet sensor Sp for detecting the pallet 80 (see FIG. 19). In the controller 61, the pallet sensor Sp detects that the forks 30a and 30b are inserted into the pallet 80 (see FIG. 19). As the pallet sensor Sp, for example, a contact sensor that turns on when a pallet comes into contact can be used.

As shown in FIG. 19, the controller 61 controls the circles C1 and C2 through which the rear corners P1 and P2 of the machine base pass and the front corners of the pallet 80 when turning at the maximum handle angle (when turning on the spot). Circles C21 and C22 as predicted trajectories that P21 and P22 pass are expressed in the world coordinate system. The controller 61 detects the relative positions of the circles C1, C2, C21, C22 and the cameras 71, 72, 73, and transforms the coordinates of the circles C1, C2, C21, C22 from the world coordinate system to the camera coordinate system. The controller 61 coordinate-transforms the circles C1, C2, C21 and C22 from the camera coordinate system to the monitor coordinate system. The controller 61 superimposes circles C1, C2, C21, and C22 on the camera image, and displays them on the display unit 63 as shown in FIGS. 20(a), (b), and (c). The vicinity of P1 and P2 is displayed.

More specifically, when turning to the left, as shown in FIG. 21(a), a circle C1 through which the rear corner P1 of the machine base passes and a circle C21 through which the front corner P21 of the pallet 80 passes are placed in the world coordinate system. expressed in Then, as shown in FIG. 21(b), the relative positions of the circles C1 and C21 and the cameras 71, 72 and 73 are detected, the coordinates of the circles C1 and C21 are transformed from the world coordinate system to the camera coordinate system, and the circle C1 , C21 are coordinate-transformed from the camera coordinate system to the monitor coordinate system, and the circles C1 and C21 are superimposed on the camera image and displayed on the display unit 63 as shown in FIG. 21(c). On the other hand, when turning to the right, the circles C2 and C22 through which the rear corner P2 of the machine base and the front corner P22 of the pallet pass are expressed in the world coordinate system, and the relative positions of the circles C2 and C22 and the cameras 71, 72, and 73 are are detected, and the circles C2 and C22 are coordinate-transformed from the world coordinate system to the camera coordinate system. Then, the circles C2 and C22 are coordinate-transformed from the camera coordinate system to the monitor coordinate system, and the circles C2 and C22 are superimposed on the camera image and displayed on the display unit 63 .

In this way, when the pallet 80 is being conveyed, the circles C21 and C22 through which the pallet front corners P21 and P22 pass during turning are displayed as guides instead of the tip ends P11 and P12 of the forks. The presence or absence of the pallet 80 is confirmed by the pallet sensor Sp at the base of the forks 30a and 30b. Since the size of the pallet 80 is determined by JIS (Japanese Standard), the turning radii of the pallet front corners P21 and P22 can be calculated. It is also assumed that the forks 30a and 30b are inserted into the pallet 80 up to their roots. Therefore, the turning radius can be easily recognized even when the pallet is conveyed. Even if a nonstandard palette is used, circles C21 and C22 can be generated and displayed if the size is known in advance.

Specifically, as shown in FIG. 22, when turning 180 degrees on the spot to change direction, the turning radius becomes maximum at the rear corner P1 of the machine base. A circle C1 is displayed as the predicted turning trajectory. By displaying the guide in this way, it is possible to easily determine whether the direction can be changed without interfering (contacting) with the obstacle.

Here, as indicated by the dashed line in FIG. 22, the tangent line Lg of the position Pm where the rear corner of the machine base bulges the most in the trajectory (C1 in FIG. 22) that the rear corner of the machine body passes is displayed as a guide display. good too.

As shown in FIG. 23, when the pallet is rotated by 90 degrees to face the pallet at its placement position, the turning radius (circle C1) is maximized at the rear corner P1 of the machine base. In the area through which the portion P1 passes, a clearance corresponding to the turning radius (C1) of the rear corner portion P1 of the machine base is required. On the other hand, in the area where the rear corner P1 of the machine base does not pass, it is sufficient to have a clearance corresponding to the turning radius (circle C21) of the front corner P21 of the pallet. In this manner, circles C1 and C21 are displayed as expected turning trajectories of the rear corner P1 of the machine base and the front corner P21 of the pallet. By displaying the guide in this way, it is possible to easily determine whether or not it is possible to face the obstacle without interfering (contacting) it.

According to this embodiment, in addition to the above (1), the following effects can be obtained.
(5) Prior to turning of the reach-type forklift 20, the controller 61 as a trajectory superimposing unit creates a circle ( C21, C22) are further generated and superimposed on the images captured by the cameras (71, 72, 73) and displayed on the display unit 63. Therefore, since the circles C21 and C22 are displayed as the predicted trajectories of the front corners P21 and P22 of the pallet, it is possible to make it easier to understand the relationship with the interfering object when the reach-type forklift 20 is turning.

(6) When the pallet sensor Sp detects the pallet 80 on the forks 30a and 30b, the controller 61 as the trajectory superimposing unit controls the front of the pallet on the opposite side of the turning direction based on the current steering angle before the reach-type forklift 20 turns. Circles (C21, C22) as predicted trajectories of the corners (P21, P22) are further generated and superimposed on the images captured by the cameras (71, 72, 73) and displayed on the display unit 63. Therefore, when the pallet 80 is detected as the forks 30a and 30b are inserted into the pallet 80, circles C21 and C22 are displayed as expected trajectories of the pallet front corners P21 and P22. You can make relationships with things easier to understand.

(Fifth embodiment)
Next, the fifth embodiment will be described, focusing on differences from the first to fourth embodiments.
When steering while traveling, for example, when making a gentle turn, the controller 61 adjusts the rear of the machine on the side opposite to the turning direction, as shown in FIG. A circle (C1, C2) is generated as the predicted trajectory of the corner (P1, P2). The controller 61 also generates circles (C51, C52) as predicted trajectories of the front corners (P51, P52) of the left and right reach legs 22a, 22b arranged on the front side of the machine base 21 in the turning direction. The controller 61 causes the display unit 63 to superimpose the images captured by the cameras 71 , 72 , and 73 on the images.

In other words, when a gentle turn is performed to avoid the obstacle M, the turning radius is maximized at the rear corners (P1, P2) of the machine base on the side opposite to the turning direction, and the turning radius is minimum. are the front corners (P51, P52) of the reach leg in the turning direction or the front wheels (see FIGS. 18(a) and 18(b)). The predicted turning trajectory of the rear corners (P1, P2) of the machine base opposite to the turning direction and the front corners (P51, P52) of the reach leg in the turning direction or the axis center of the front wheels is generated and displayed.

Also, circles C51 and C52 (or circles C61 and C62) as predicted turning trajectories of reach leg front corners P51 and P52 (or front wheel shaft centers P61 and P62) and predicted turning trajectories of rear corners P1 and P2 of the machine base A region Z1 sandwiched between the circles C1 and C2 is displayed on the display unit 63 so as to be distinguished from other regions. For example, by giving the area Z1 a different color than the other areas or giving a different shade than the other areas, the area Z1 is the area through which the machine base passes, and it is possible to judge interference (contact) with an obstacle. make it easier to do.

By displaying the guide in this manner, it is possible to easily determine whether or not the current steering angle allows the vehicle to proceed without interfering with (contacting) an obstacle.
Similarly, as shown in FIG. 25, the turning radius is maximized at the rear corners (P1, P2) of the machine base on the side opposite to the turning direction, and the turning radius is minimum at the corners in the turning direction. These are the pallet front corners (P21, P22). The controller 61 predicts turning trajectories of the machine base rear corners (P1, P2) on the side opposite to the turning direction and the pallet front corners (P21, P22) on the turning direction in accordance with the turning (steering angle) command value. Circles C1, C2, C21 and C22 are generated and displayed.

A region Z2 sandwiched between circles C21 and C22 as predicted turning trajectories of the pallet front corners P21 and P22 and circles C1 and C2 as predicted turning trajectories of the rear corners P1 and P2 of the machine base is defined as another region. They are displayed on the display unit 63 so as to be distinguished from each other. For example, by giving the area Z2 a different color or shade than other areas, the area Z2 is an area through which the machine base passes, and interference (contact) with an obstacle can be determined. make it easier to do.

According to this embodiment, instead of the above (2), the following effects can be obtained.
(7) As described with reference to FIG. 25, the controller 61 as a trajectory superimposing unit generates circles (C21, C22) as expected turning trajectories of the pallet front corners (P21, P22) in the turning direction, The display unit 63 displays an area Z2 sandwiched between the circles (C1, C2) as the predicted trajectories of the rear corners (P1, P2) of the machine base on the opposite side to distinguish it from the other areas. Therefore, when the reach-type forklift 20 turns, the relationship with the interfering object can be made easier to understand.

(8) As described with reference to FIG. 24, the controller 61 as the trajectory superimposing unit generates circles (C51, C52 ) or circles (C61, C62) as expected trajectories of the axis centers (P61, P62) of the front wheels (23a, 23b) in the turning direction, and the rear corners (P1, P2) of the machine base on the side opposite to the turning direction. The area Z1 sandwiched between the circles (C1, C2) as the predicted trajectory is displayed on the display unit 63 so as to be distinguished from other areas. Therefore, when the reach-type forklift 20 turns, the relationship with the interfering object can be made easier to understand.

Embodiments are not limited to the above, and may be embodied as follows, for example.
○ With respect to (3) and (5) above, prior to turning the forklift, the trajectory superimposed portion is calculated based on the current steering angle, either at the tip of the pair of left and right forks on the side opposite to the turning direction or with the turning direction. , the predicted trajectory of the front corner of the pallet on the opposite side may be further generated, superimposed on the image captured by the camera, and displayed on the display unit.

○ The number of cameras does not matter.
○ Although the forklift was a reach-type forklift, it is not limited to this, and a forklift other than a reach-type forklift may be used. For example, in the case of a counter-type forklift, since there is no reach leg, the predicted turning trajectory centered on the front axle is always displayed.

That is, as shown in FIG. 26 , a counter-type forklift 90 includes a cargo handling device 92 on a machine base 91 . The counter-type forklift 90 also includes a right front wheel 93a, a left front wheel 93b, a right rear wheel 94a, and a left rear wheel 94b. As shown in FIG. 27, the right front wheel 93a has an axial center P71. The left front wheel 93b has an axial center P72. Then, prior to turning of the forklift, the controller 61 as a locus superimposing unit creates a circle ( C71, C72) may be further generated and superimposed on the images captured by the cameras 71, 72, 73 and displayed on the display unit 63.

DESCRIPTION OF SYMBOLS 10... Remote control system for forklifts, 20... Reach type forklift, 21... Machine base, 22a, 22b... Reach legs, 23a, 23b... Front wheels, 28... Cargo handling device, 30a, 30b... Forks, 40... Remote control device, 52... Radio unit 54 Radio device 61 Controller 63 Display unit 64, 65 Radio device 71, 72, 73 Camera 80 Pallet 90 Counter type forklift 91 Machine base 92 Cargo handling Device, 93a, 93b... front wheels C1, C2, C11, C12, C21, C22, C51, C52, C61, C62, C71, C72... circles, P1, P2... rear corners of machine base, P11, P12... fork tips , P21, P22 .

Claims (5)

a forklift having a cargo handling device on the machine base and a vehicle communication unit;
A remote control system for a forklift, comprising: a remote control device that has a control device communication unit that performs wireless communication with the vehicle communication unit, and that is used to remotely control traveling of the forklift and cargo handling by the cargo handling device. hand,
a camera mounted on the forklift for imaging the surroundings of the forklift;
a display unit provided in the remote control device for displaying an image captured by the camera;
Prior to turning the forklift, a predicted trajectory of the rear corner of the machine base on the side opposite to the turning direction is generated based on the current steering angle, superimposed on the image captured by the camera, and displayed on the display unit. a trajectory superimposing unit ,
When the pallet sensor detects the pallet on the fork, the trajectory superimposing unit further generates a predicted trajectory of the front corner of the pallet on the side opposite to the turning direction based on the current steering angle prior to turning the forklift, and outputs the predicted trajectory to the camera. 1. A remote control system for a forklift, characterized in that the image is superimposed on the image picked up by the remote control unit and displayed on the display unit . a forklift having a cargo handling device on the machine base and a vehicle communication unit;
A remote control system for a forklift, comprising: a remote control device that has a control device communication unit that performs wireless communication with the vehicle communication unit, and that is used to remotely control traveling of the forklift and cargo handling by the cargo handling device. hand,
a camera mounted on the forklift for imaging the surroundings of the forklift;
a display unit provided in the remote control device for displaying an image captured by the camera;
Prior to turning the forklift, a predicted trajectory of the rear corner of the machine base on the side opposite to the turning direction is generated based on the current steering angle, superimposed on the image captured by the camera, and displayed on the display unit. a trajectory superimposing unit ,
The forklift is a reach-type forklift,
Prior to turning of the forklift, the trajectory superimposing unit is a predicted trajectory or a machine trajectory of a front corner of one of the pair of left and right reach legs arranged on the front side of the machine body, which is opposite to the turning direction, based on the current steering angle. Of the left and right front wheels provided on a pair of left and right reach legs arranged on the front side of the stand, the predicted trajectory of the center of the axis of the front wheel on the side opposite to the turning direction is further generated and superimposed on the image captured by the camera. A remote control system for a forklift, characterized in that the display unit displays a remote control system for a forklift. The trajectory superimposing unit distinguishes an area sandwiched between the expected trajectory of the front corner of the pallet in the turning direction and the expected trajectory of the rear corner of the machine base opposite to the turning direction from other areas. 2. The remote control system for a forklift according to claim 1 , wherein the information is displayed on a display unit. The trajectory superimposed portion is sandwiched between the expected trajectory of the front corner of the reach leg in the turning direction or the expected trajectory of the center of the front wheel shaft in the turning direction and the expected trajectory of the rear corner of the machine on the side opposite to the turning direction. 3. The forklift remote control system according to claim 2 , wherein the area is displayed on the display unit so as to be distinguished from other areas. a forklift having a cargo handling device on the machine base and a vehicle communication unit;
A remote control system for a forklift, comprising: a remote control device that has a control device communication unit that performs wireless communication with the vehicle communication unit, and that is used to remotely control traveling of the forklift and cargo handling by the cargo handling device. hand,
a camera mounted on the forklift for imaging the surroundings of the forklift;
a display unit provided in the remote control device for displaying an image captured by the camera;
Prior to turning the forklift, a predicted trajectory of the rear corner of the machine base on the side opposite to the turning direction is generated based on the current steering angle, superimposed on the image captured by the camera, and displayed on the display unit. a trajectory superimposing unit ,
The forklift is a counter-type forklift,
Prior to turning of the forklift, the trajectory superimposing unit further generates a predicted trajectory of the center of the shaft of one of the left and right front wheels on the side opposite to the turning direction based on the current steering angle, and the predicted trajectory is captured by the camera. A remote control system for a forklift , wherein the image is superimposed on the image and displayed on the display unit .

Images