Control method for road marking application equipment

Abstract

This invention aims to automate the painting machine using a self-propelled trolley, and provides a road marking application device and control method that can apply a uniform spray width regardless of the road surface condition by changing the spray position vertically and horizontally based on vehicle travel information, road surface height, and actual painting conditions. [Solution] A self-propelled trolley is equipped with a painting machine 26 using a spray gun 16, a position measuring camera 5 for tracing the state of pre-created marking lines or existing road markings 6, an acceleration sensor 17, and a spray gun height detection sensor 19. The spray gun 19 is equipped with a horizontal sliding device 13 and a vertical sliding device 14, allowing it to move not only horizontally but also vertically.

Description

Technical Field

[0001] The present invention relates to a control method for a road marking construction apparatus that aims to automate painting for road marking construction.

Background Art

[0002] As a road marking construction apparatus for constructing markings such as division lines including roadway center lines, lane boundary lines and roadway outer lines, and no-passing lines on a road surface, there is known an apparatus that draws in advance a reference line indicating the position where the marking is to be constructed on the road surface, and sprays paint onto the reference line to construct the marking while a construction vehicle equipped with a painting device that discharges paint is traveling.

[0003] There are various types of road marking construction apparatuses, such as those installed on vehicles traveling on the road surface and self-propelled carriage type apparatuses. To describe one example with reference to Figure 1, a paint tank, a paint pump, a bead tank, a battery, and a compressor (not shown) are mounted on the painting device mount of a self-propelled electric traveling carriage provided with traveling tires for self-propulsion and dependent casters, and a spray gun and a bead gun are provided as painting machines.

[0004] The battery supplies power to the painting machines and the compressor, the paint pump is a paint pressure-feeding pump, the spray gun is a device that discharges paint onto the road surface to construct white lines, and the bead gun is a device that sprays beads onto the paint film applied by the spray gun.

[0005] The road marking construction apparatus is of a type installed on a vehicle traveling on the road surface, and the following patent documents disclose a technology that draws in advance a reference line indicating the position where the marking is to be constructed on the road surface, and sprays paint onto the reference line to construct the marking while a construction vehicle equipped with a painting device that discharges paint is traveling.

Patent Document 1

Patent Document 2

[0006] The aforementioned Patent Document 2 aims to provide a road marking application device that can easily and accurately apply road markings, overcoming the difficulty in applying paint to the road surface and applying markings, particularly on curved roads, when using the application vehicle described in Patent Document 1, which relies on images displayed in the rear image display area.

[0007] The road marking application device of Patent Document 2 is provided on the side of a vehicle and includes a painting unit that applies paint to a painting position on the road surface to paint a linear marking; a front camera that captures a forward imaging area that includes a reference line shown on the road surface in front of the vehicle, among the reference lines that are shown on the road surface in advance, where the planned painting position is to be painted; a rear camera that captures a rear imaging area that includes the reference line shown on the road surface behind the road surface captured by the front camera; a front image display unit that displays the image captured by the front camera; and a rear image display unit that displays the image captured by the rear camera, wherein the rear imaging area includes the area on the road surface from the painting position to a position 1 m in the direction of travel of the vehicle. [Overview of the project] [Problems that the invention aims to solve]

[0008] Patent documents 1 and 2 only describe the lateral movement of the spray, and do not mention vertical movement. Without the ability to move the spray vertically, it is not possible to paint with a consistent width regardless of the unevenness or incline of the road surface.

[0009] The objective of the present invention is to overcome the disadvantages of the conventional example and automate the painting machine using a self-propelled trolley, and to provide a control method for a road marking application device that can perform application with a uniform spray width regardless of the road surface condition by changing the spray position up and down and left and right based on the vehicle's running information, the height of the road surface, and the actual painting condition. [Means for solving the problem]

[0010] To achieve the above objective, the present invention uses a road marking construction device characterized by using a self-propelled trolley equipped with a spray gun painting machine, a position measuring camera for tracing the state of pre-created marking lines or existing road markings, an acceleration sensor, and a spray gun height detection sensor, wherein the spray gun is equipped with a lateral sliding device and an up-and-down sliding device so that it can move not only horizontally but also vertically. The device traces the state of pre-created marking lines or existing road markings with the position measuring camera, estimates the pitch, roll, and yaw information from the acceleration sensor and the position of the spray gun from the height detection sensor, moves the position of the spray gun using the lateral sliding device and the up-and-down sliding device based on the estimated spray gun position, and performs spraying with the spray gun. The essence of the invention is to perform spray correction with the spray gun by adjusting the travel speed of the self-propelled trolley or by adjusting the pressure of the spray pump.

[0011] According to the present invention, a self-propelled trolley travels by tracing the state of pre-created marking lines or existing road markings using a position-measuring camera.

[0012] An acceleration sensor is used to obtain information on pitch, roll, and yaw. This information, along with a height detection sensor placed in front of the spray gun, is used to estimate the position of the spray gun.

[0013] Based on the estimated spray gun position, the spray gun's position is moved using motors that move it up and down and left and right, and then spraying is performed.

[0014] As described above, by moving the spray gun in the left-right direction using a lateral sliding device, the direction is basically determined by the vehicle's steering. However, relying solely on the vehicle's movement results in a large moment of inertia for the vehicle, a slow response time to control, and structurally difficult minute (on the order of millimeters) steering. By using a motor-driven left-right sliding motion, quick and precise lateral corrections can be made.

[0015] Furthermore, by moving the spray gun in the vertical direction with a vertical slide device, changes in coating width caused by unevenness and pitch deviations of the road surface can be homogenized by the spray position.

[0016] According to the present invention described in Claim 2 and Claim 3, spray correction with the spray gun can be performed by adjusting the traveling speed of the self-propelled carriage, or by adjusting the pressurization of the spray pump. Effects of the Invention

[0017] As described above, the road marking construction apparatus and the control method thereof of the present invention achieve automation of the coating machine by means of a self-propelled carriage, and by changing the spray position vertically and horizontally based on vehicle traveling information, road surface height, and actual coating state, construction can be performed with a uniform spray width regardless of the road surface condition. Brief Description of the Drawings

[0018] [Figure 1] It is a rear perspective view showing one embodiment of the road marking construction apparatus of the present invention. [Figure 2] It is a front perspective view showing one embodiment of the road marking construction apparatus of the present invention. [Figure 3] It is a perspective view of the coating machine portion that is the main part of the road marking construction apparatus of the present invention. [Figure 4] It is a hardware block diagram for performing the control method of the present invention. [Figure 5] It is an explanatory diagram showing a coating path. [Figure 6] It is a flow diagram of initial setting. [Figure 7] It is a flow diagram of spray position change. [Figure 8] It is a work flow diagram of the automatic coating machine. [Figure 9] It is a flow diagram of coating evaluation (in the case of performing speed change). [Figure 10] It is a flow diagram of coating evaluation (in the case of performing pressure change). [Figure 11]This is a perspective view of a self-propelled trolley in motion. [Figure 12] This is a plan view of the self-propelled trolley in motion. MODE FOR CARRYING OUT THE INVENTION

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, the road marking construction apparatus used in the present invention will be described.

[0020] Fig. 1 is a rear perspective view showing an embodiment of the road marking construction apparatus of the present invention, and Fig. 2 is a front perspective view of the same, wherein a paint tank, a paint pump, a bead tank, a battery, and a compressor (not shown) are mounted on the painting apparatus mount of an automatic electric traveling trolley equipped with traveling tires for self-propulsion and follower casters, and a painter is attached thereto.

[0021] The battery supplies power to the painter and the compressor, the paint pump is a paint pressure-feeding pump, the spray gun of the painter is an apparatus that discharges paint onto the road surface to construct road marking lines, and the bead gun is an apparatus that scatters beads onto the paint film applied by the spray gun.

[0022] The painter has a slide device. In this slide device, a vertical slide device is attached to a horizontal slide device, and the horizontal slide device and the vertical slide device are configured to not only move the bead gun and the spray gun in the left-right direction but also in the up-down direction.

[0023] In the horizontal slide device, a gun holder left-right moving motor (actuator) provided on the vehicle body of the automatic electric traveling trolley extends and retracts the cylinder rod of the cylinder, and a holder portion is provided on the cylinder rod.

[0024] The vertical sliding device 14 is installed at the tip of the holder portion and moves the movable body 14b up and down using a ball screw that is rotationally driven by the spray holder vertical movement motor (actuator) 14a.

[0025] The bead gun 16 and spray gun 15 are supported by a support arm 27 attached to the movable body 14b of the vertical sliding device 14.

[0026] In the diagram, 35 is a travel path recognition camera, which is installed at any position on the upper part of the automatic electric travel trolley 11 and is used to detect existing lines at a distance.

[0027] The route recognition camera 35 detects existing tracks 3 to 20 meters ahead in the direction of travel, which is used only when tracing existing tracks, and determines the direction of travel for the vehicle.

[0028] As shown in Figures 11 and 12, the travel path recognition camera 35 creates a virtual travel line 37, and the automated electric travel vehicle 11 travels along the virtual travel line 37.

[0029] In the figure, 5 is a position measuring camera, which is installed at the upper end of the vertical sliding device 14, and a displacement meter 20 is installed on the holder portion of the horizontal sliding device 13. The displacement meter 20 measures the displacement of the holder portion as the horizontal sliding device 13 moves left and right by extending and retracting the cylinder rod of the cylinder.

[0030] The aforementioned support arm 27 also supports the paint measurement camera 7 at the rear of the bead gun 16.

[0031] The cameras installed on the automatic electric trolley 11 are the travel path recognition camera 35, the position measurement camera 5, and the paint measurement camera 7. The travel path recognition camera 35 is as described above, the position measurement camera 5 is a camera that detects the position of the drawn line and the existing line 6 in front of the vehicle, and the paint measurement camera 7 is a camera that measures the spray width of the newly applied road markings 33 on the road surface. In the figure, 9 shows the forward shooting area by the position measurement camera 5.

[0032] Furthermore, the automatic electric trolley 11 is equipped with various sensors, including an acceleration sensor (gyro sensor) 17, a LiDAR sensor 18, and a height sensor 19.

[0033] The acceleration sensor (gyro sensor) 17 is installed in the center of the body of the automatic electric trolley 11 and measures the roll, pitch, and yaw rotation angles of the vehicle body.

[0034] The LiDAR sensor 18 detects obstacles around the vehicle body to ensure safety or to stop the machine.

[0035] The height detection sensor 19 measures the distance of the spray gun from the ground using ultrasound.

[0036] As shown in Figure 4, the present invention provides two control units, a vehicle body control unit 21 and a painting control unit 22, to control the vehicle body and painting. It is also possible to configure the vehicle body control unit 21 and the painting control unit 22 as a single unit rather than separating them into two separate units.

[0037] The vehicle control unit 21, consisting of a processor 21a, memory 21b, and communication circuit 21c, receives outputs from the acceleration sensor (gyro sensor) 17, LiDAR sensor 18, and GNSS 23, and communicates input and output with the position measurement camera 5 and the paint measurement camera 7. Although not shown in the diagram, the vehicle control unit 21 also communicates input and output with the driving path recognition camera 35.

[0038] Furthermore, the vehicle control unit 21 handles the input and output of the manual control unit, the travel motor, and the speed sensor.

[0039] Furthermore, the vehicle control unit 21 communicates with the information terminal 31, which interacts with the storage 32.

[0040] The painting control unit 22, consisting of a processor 22a, memory 22b, and communication circuit 22c, receives sensor values ​​from the height sensor 19, painting pressure sensor 24, and flow rate discharge sensor 25, and outputs them to the fuel pump 3, spray gun 15, gun holder left / right movement motor (actuator) 13a, and spray holder up / down movement motor (actuator) 14a.

[0041] Figure 5 shows the painting path, which is a piping path from the fuel tank 4 to the spray gun 15. A pressure regulator 28 is attached to the fuel pump 3, and a strainer that stores high-pressure fluid and reduces spray pulsation, an accumulator 27, a paint pressure sensor 24, and a discharge flow rate sensor 25 are sequentially installed on the discharge side piping of this fuel pump 3.

[0042] The pressure regulator 28 is a valve that can adjust the amount of pressure exerted by the fuel pump 3, which is a flow booster pump.

[0043] The road marking application device of the present invention is powered entirely by electricity and can perform the driving and painting processes automatically.

[0044] The automatic electric trolley 11 can determine its travel speed by the rotation speed of its running tires 29, and can also change direction, rotate, reverse, and perform other driving controls by changing the rotation speed and direction of rotation of the left and right running tires 29.

[0045] Conventionally, skilled workers manually adjusted the gun height sequentially while checking the paint width and tracing the lines, as they drew the plans and traced existing lines. To enable even inexperienced workers to perform the work, the automated mobile application machine automatically adjusts the gun height according to the road surface conditions while drawing the plans and tracing existing lines. To further improve application accuracy, it automatically corrects the gun's lateral movement, discharge pressure, and travel speed based on acceleration sensors and discharge flow rate.

[0046] This invention uses the aforementioned road marking construction device, (1) Trace the pre-created marking lines or existing road markings using a position measurement camera. (2) The position of the spray gun is estimated using pitch, roll, and yaw information from the acceleration sensor and height detection sensor. (3) Based on the estimated spray gun position, the position of the spray gun is moved using the up and down and left and right motors of the lateral sliding device and the vertical sliding device. (4) Spray with a spray gun It is.

[0047] First, let's describe the operation of the automated electric trolley 11. The travel path recognition camera 35 is used only when tracing the existing line 34. It detects the existing line 34 at a distance. In the figure, 36 is the existing line detection area.

[0048] When tracing the existing line 34 in this way, the bogie travels along a virtual running line, allowing the position measurement camera 5 to detect the existing line 35 and perform painting according to the pattern (solid line / dashed line) of the existing line 34.

[0049] When tracing a drawing line, the automatic electric trolley 11 traces the drawing line detected by the position measuring camera 5 and performs painting.

[0050] The initial setup flow is as follows, as shown in Figure 6: set the driving speed, set the pressure of the fuel pump 3, set the height of the spray gun 15, test the spray of the spray gun 15, set the flow rate to confirm that it is the specified flow rate (since flow rate = discharge amount = coating amount), check the spray pattern to confirm that the spray width of the spray gun 15 is the specified width, and confirm that both the spray width and flow rate of the spray gun 15 are OK.

[0051] As shown in Figure 7, the workflow for the painting machine involves initial setup, waiting to start, changing the spray position, and then spraying. After that, a painting evaluation is performed, and the spray is stopped.

[0052] As shown in Figure 8, the change in the spray position is determined by detecting the drawn line and existing line 6 from the position measurement camera 5 and determining the deviation from the vehicle.

[0053] If there is a discrepancy with the vehicle, the position of the spray gun 15 is determined by detecting the position of the position measurement camera 5 and the discrepancy with the vehicle.

[0054] The left-right position is determined by applying a correction value determined by the paint evaluation process. (At the start of spraying, the correction value is set to 0.)

[0055] The left-right movement motor of the spray gun 15's gun holder is operated. Based on the discrepancy with the vehicle and the correction value, the spray gun 15 is moved to a determined position.

[0056] Position information is acquired by the height detection position sensor 19. The amount of vertical movement of the spray gun 15 is determined from the set value set in the initial settings and the amount of deviation from the information from the height detection position sensor 19.

[0057] The vertical position of the spray gun 15 is determined by applying a correction value determined by the paint evaluation process. (At the start of spraying, the correction value is set to 0.)

[0058] The spray holder vertical movement motor (actuator) 14a, which moves the spray gun 15 vertically, is operated to move the spray gun 15 to the position determined by the height difference and correction value.

[0059] When performing the aforementioned paint evaluation process, one method can be employed that involves changing the speed (Figure 9) or changing the pressure (Figure 10).

[0060] To explain the case of changing the speed first, the spray width of the applied road marking 33 is measured from the paint measurement camera 7 to determine whether it is within the specified width, and if there is a deviation from the specified width, it is corrected downwards if the specified width >, and upwards if the specified width <. From the real-time image of the paint measurement camera 7, the paint width immediately after painting is measured, the amount of deviation from the specified width (15 or 20 cm) is determined, and the correction value for the spray gun height is calculated.

[0061] The vehicle acceleration sensor 17 determines the future vehicle position from the (roll, pitch, and yaw angles) and reflects this in the correction values ​​for the position and travel speed of the spray gun 15. The vehicle acceleration sensor 17 is a sensor that determines the direction in which the vehicle is moving in three dimensions.

[0062] In roll detection, if roll is detected, a correction is applied in the left-right direction in the opposite direction to the roll. The correction value for the spray gun's left-right position is determined according to the roll angle. (By correcting in the opposite direction to the road surface's transverse inclination, tracking performance is improved.)

[0063] In yaw detection, if yaw is detected, a correction is made in the left-right direction in the opposite direction to the yaw. Since the rotation angle can be determined from the yaw angle, the correction value for the left-right position of the spray gun is set to a position that anticipates the turning motion. (Following performance is improved by correcting in the opposite direction to the direction of travel of the trolley.) The roll-yaw correction value is the correction value for the left-right direction of the spray gun.

[0064] In pitch detection, if there is a pitch and a deviation from the specified width, acceleration is performed if the deviation is in the positive direction, and deceleration if the deviation is in the negative direction. The speed is kept constant by changing the rotation speed of the wheels according to the pitch angle.

[0065] To determine whether the flow rate is appropriate, if there is a change in flow rate, acceleration is performed when the flow rate is greater than the recommended rate, and deceleration is performed when the flow rate is less than the recommended rate. Since the paint flow rate = discharge rate = coating rate, the wheel rotation speed is changed to keep the coating rate constant. The coating rate is the amount of paint per unit area, and the coating rate per unit area increases when traveling slowly and decreases when traveling quickly.

[0066] Next, we will discuss the case where pressure is changed. This pressure change is performed on the fuel pump 3 by a pressure regulator 28.

[0067] The spray width of the applied road markings 33 is measured using the paint measurement camera 7 to determine whether it is within the specified width. If there is a deviation from the specified width, the system corrects it by lowering it if the specified width is greater than the specified width, or by raising it if the specified width is less than the specified width.

[0068] The paint width immediately after painting is measured from real-time images from the paint measurement camera, the deviation from the specified width (15 or 20 cm) is determined, and a correction value for the spray gun height is calculated.

[0069] The vehicle acceleration sensor 17 determines the future vehicle position from the (roll, pitch, and yaw angles) and reflects this in the correction value of the spray gun 15's position and the driving speed, similar to when changing the speed. Roll, yaw, and pitch are determined to determine whether the flow rate is appropriate. If there is a change in flow rate, the flow rate is set to > pressure + and flow rate < pressure -.

[0070] Since the paint flow rate = discharge rate = coating rate, the pump pressure is changed to keep the coating rate constant. The coating rate is the amount of paint per unit area, and the coating rate per unit area increases when moving slowly and decreases when moving quickly.

[0071] Thus, in this invention, the automated trolley determines the positions of drawn lines and existing lines from analysis data obtained by the forward position measurement camera 5 and traces them.

[0072] Furthermore, beads are pumped or naturally flowed from the bead tank 1 through a hose and then sprayed onto the painted lines on the road surface using a bead gun 16.

[0073] As described above, in this invention, the paint width of the lines painted on the road surface is detected by the paint measurement camera 7, and the paint width can be automatically adjusted to a set value based on the distance between the road surface and the spray gun 15 as determined by the height detection sensor 19.

[0074] The acceleration sensor 17 of the automatic electric trolley 11 detects the lateral deviation of the paint position due to the tilt of the vehicle, or the paint measurement camera 7 detects deviations from the drawn line or existing line, and the gun holder left and right movement motor 13a adjusts accordingly. [Explanation of symbols]

[0075] 1… Bead Tank 2…Battery 3…Paint pump 4… Paint tank 5…Location measurement camera 6…Drawing lines / existing lines 7…Paint measurement camera 8…Sliding device 9…Forward shooting area 10… Paint width detection area 11…Automatic electric trolley 12…Painting equipment stand 13… Lateral sliding device 14…Vertical sliding device 13a... Gun holder left / right movement motor (actuator) 14a... Spray holder vertical movement motor (actuator) 14b... Rack-type mobile unit 15... Spray gun 16... Bead gun 17…Accelerometer (gyroscope) 18…LiDAR sensor 19…Height detection position sensor 20... Displacement gauge 21... Vehicle body control unit 21a…Processor 21b...Memory 21c...communication circuit 22a… Processor 22...Painting Department 22a… Processor 22b...Memory 22c…Communication circuit 23…GNSS 24…Paint pressure sensor 25…Discharge flow sensor 26... Painting machine 27... Strainer, accumulator 28... Pressure regulator 29… Driving tires 30... Subordinate Caster 31… Information terminal 32...Storage 33…Installed road markings 34… Existing lines 35… Driving path recognition camera 36… Existing line detection area 37… Virtual Driving Line

Claims

1. A road marking application device characterized by having a spray gun painting machine, a position measuring camera for tracing pre-created marking lines or existing road markings, an acceleration sensor, and a spray gun height detection sensor mounted on a self-propelled trolley, and the spray gun being able to move not only horizontally but also vertically by having a vertical sliding device attached to the horizontal sliding device.

2. The road marking construction device according to claim 1, wherein a travel path recognition camera for detecting existing lines at long distances is installed at an arbitrary position on the upper part of a self-propelled trolley.

3. The road marking application device uses a self-propelled trolley equipped with a spray gun painting machine, a position measuring camera for tracing pre-created marking lines or existing road markings, an acceleration sensor, and a spray gun height detection sensor, and the spray gun is equipped with a vertical sliding device on the horizontal sliding device so that it can move not only horizontally but also vertically. The vehicle traces the pre-created marking lines or existing road markings using a position-measuring camera. The pitch, roll, and yaw information from the acceleration sensor and the position of the spray gun from the height detection sensor are estimated. A control method for a road marking application device, characterized by moving the position of the spray gun using a lateral sliding device and a vertical sliding device based on the estimated position of the spray gun, and then performing spraying with the spray gun.

4. A control method for a road marking construction device according to claim 3, in which spray correction with a spray gun is performed by adjusting the travel speed of a self-propelled trolley.

5. A control method for a road marking application apparatus according to claim 1, wherein spray correction with a spray gun is performed by adjusting the pressure of the spray pump.

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