Automobile door sealing strip automatic rolling system based on 3D structured light camera

Abstract

The invention relates to a vehicle door sealing strip automatic rolling system based on a 3D structured light camera, which comprises a six-axis robot and a vehicle door fixing mechanism, the six-axis robot is connected with an industrial personal computer, and the movable tail end of the six-axis robot is fixedly provided with the 3D structured light camera and a sealing strip rolling pasting device which are connected with the industrial personal computer; a 3D structured light camera calibrated with the six-axis robot in advance is adopted to obtain vehicle door point cloud data containing vehicle door key points, and point cloud offset information is obtained according to the vehicle door point cloud data and vehicle door point cloud data of a vehicle door standard position shot by the 3D structured light camera in advance at the same position; and according to the point cloud offset information, a virtual vehicle door rolling pasting track sequence corresponding to the vehicle door standard position pre-written into the six-axis robot is adjusted, the actual vehicle door rolling pasting track sequence obtained after adjustment is adopted for operation, and the sealing strip is rolled and pasted to the corresponding position of the vehicle door through a sealing strip rolling pasting device. Compared with the prior art, the system has the advantages of high automation degree, high reliability and the like.

Description

Technical Field

[0001] The present invention relates to the field of automobile production and processing, and in particular to an automatic rolling system for door sealing strips based on a 3D structured light camera. Background Art

[0002] Door seals are widely used in various types of vehicles, and their main functions are dust and noise prevention and buffering. At present, adhesive door seals are widely used, which are mainly installed on the door by pressing or rolling. At present, most automobile manufacturers use this installation method, which can ensure the installation accuracy, but requires people to cooperate with the installation. The equipment and tooling need to be specially developed according to the vehicle model, with a relatively high comprehensive cost, a relatively low degree of automation, and a low degree of adaptability.

[0003] With the popularization of robots, the application of rolling installation method has gradually increased. However, because the robot's operating trajectory is fixed and the position of the incoming door hanger is deviated, it greatly affects the accuracy of the door sealing strip pasting. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a door sealing strip automatic rolling system based on a 3D structured light camera with high automation and good installation quality.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] An automatic rolling system for door sealing strips based on a 3D structured light camera, comprising a six-axis robot and a door fixing mechanism, wherein the six-axis robot is connected to an industrial computer, and a 3D structured light camera and a sealing strip rolling and pasting device connected to the industrial computer are fixed at the movable end of the six-axis robot;

[0007] The 3D structured light camera pre-calibrated with the six-axis robot is used to obtain the door point cloud data containing the key points of the door, and the point cloud offset information is obtained based on the door point cloud data and the door point cloud data of the standard door position pre-photographed by the 3D structured light camera at the same position;

[0008] The virtual door rolling and pasting trajectory sequence corresponding to the standard door position pre-written into the six-axis robot is adjusted according to the point cloud offset information. The six-axis robot runs with the actual door rolling and pasting trajectory sequence obtained after the adjustment, and the sealing strip is rolled and pasted to the corresponding position of the door through the sealing strip rolling and pasting device set at the active end.

[0009] Preferably, the first door position of the set model fixed by the door fixing mechanism is used as the standard door position, and the process of acquiring the virtual door rolling trajectory sequence corresponding to the standard door position is specifically as follows:

[0010] Establish a model for the automatic rolling project of door sealing strips in the machine vision software, and establish the six-axis robot base coordinate system with the six-axis robot base as the origin;

[0011] Import the 3D image of the car door into the project model of automatic rolling of the door seal strip;

[0012] Control the movable end of the six-axis robot to move to multiple key points in the first door in sequence, obtain the actual coordinates of the six-axis robot, write the actual coordinates of the six-axis robot as the coordinates of the key points of the virtual door into the door sealing strip automatic rolling project model, and determine the door position in the virtual environment;

[0013] After the door position in the virtual environment is determined, a virtual door rolling trajectory sequence corresponding to the door standard position is obtained.

[0014] Preferably, the machine vision software pre-stores the door sealing strip automatic rolling project models corresponding to multiple different types of vehicle doors, and automatically calls the pre-stored door sealing strip automatic rolling project models corresponding to the vehicle doors according to the vehicle door models.

[0015] Preferably, the door point cloud data containing door key points includes at least three door key points.

[0016] Preferably, the six-axis robot and the 3D structured light camera are calibrated using a hand-eye calibration method based on Eye-In-Hand.

[0017] Preferably, the six-axis robot and the 3D structured light camera are calibrated each time the door model is changed or at set intervals.

[0018] Preferably, the door fixing mechanism is fixed with a visual calibration plate at a set position for calibrating the six-axis robot and the 3D structured light camera.

[0019] Preferably, during the automatic rolling process of the door sealing strip, the movement speed of the robot is adaptively adjusted according to the shape of the door, specifically including:

[0020] Starting from the starting point, the vehicle is accelerated to a first speed according to a first acceleration and then runs at a constant speed;

[0021] When the curvature increases and begins to exceed the first threshold, the speed is reduced to the second speed;

[0022] When the curvature increases and begins to exceed the second threshold, the speed is reduced to the third speed;

[0023] When the curvature decreases and begins to be less than a second threshold, the speed is increased to a second speed;

[0024] When the curvature decreases and begins to be less than the first threshold, the speed is increased to the first speed;

[0025] When it is detected that the distance from the starting point is less than the set value, the speed is reduced to the fourth speed, and then it is decelerated to the fifth speed according to the second acceleration until the starting point is detected and then it stops running.

[0026] Preferably, the sealing strip rolling and pasting device comprises a fixing mechanism for fixing the sealing strip rolling and pasting device on the movable end of the six-axis robot, and a feeding mechanism, a buffer mechanism, a stripping mechanism, a discharging mechanism, a rolling mechanism and a cutting mechanism arranged in sequence according to the travel path of the sealing strip;

[0027] The sealing strip with the isolation paper passes through the feeding mechanism, the buffer mechanism, the peeling mechanism and the discharging mechanism in sequence, and then the sealing strip with the isolation paper peeled off is rolled and bonded to the set position of the car door through the rolling position. After one circle of rolling and bonding, the adhesive strip is cut off by the cutting mechanism, and the sealing strip rolling and bonding device is stopped.

[0028] Preferably, the sealing strip rolling and pasting device further comprises:

[0029] A speed sensor and an encoder are provided at the entrance of the feeding mechanism, and when an abnormal feeding speed or single feeding length is detected, the operation is stopped; and / or

[0030] A speed sensor and an encoder are provided at the outlet of the discharging mechanism, and when an abnormal discharging speed or single discharging length is detected, the mechanism stops running; and / or

[0031] A photoelectric sensor for detecting the release paper peeled off the sealing strip is arranged at the outlet of the discharging mechanism. When the release paper cannot be detected, the operation is stopped.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The present invention uses a 3D structured light camera to collect door point cloud data. The current door position offset information can be obtained through the offset between the actual door point cloud data and the door point cloud data at the standard position. The coordinates of the virtual door rolling and pasting trajectory sequence pre-written in the six-axis robot are adjusted according to the offset information. The six-axis robot runs using the actual door rolling and pasting trajectory sequence obtained after the adjustment. The sealing strip rolling and pasting device set at the movable end rolls and pastes the sealing strip to the corresponding position of the door. The automatic rolling process of the sealing strip can be completed more accurately, further improving the sealing strip rolling and pasting installation quality.

[0034] (2) The machine vision software pre-stores the door seal strip automatic rolling project models corresponding to multiple different types of doors. The pre-stored door seal strip automatic rolling project models corresponding to the door are automatically called according to the door model. Only the 3D structured light camera is required to collect the actual door point cloud information to realize the door rolling trajectory calibration, which is more reliable and convenient.

[0035] (3) Each time the door model is changed or at set intervals, the six-axis robot and the 3D structured light camera are calibrated to ensure the calibration reliability of the six-axis robot and the 3D structured light camera;

[0036] (4) Installing the visual calibration plate at the set position of the door fixing mechanism can ensure that the placement position and angle of the visual calibration plate are close to the door surface, further improving the reliability and accuracy of the calibration.

[0037] (5) During the automatic rolling process of the door sealing strip, the robot's movement speed is adaptively adjusted according to the shape of the door, and different rolling rates are used under different curvatures, which increases safety and reliability.

[0038] (6) A speed sensor, an encoder and a photoelectric sensor are provided in the sealing strip rolling and pasting device. When the feeding and discharging speed is abnormal, the single feeding and discharging length is abnormal, or the isolation paper cannot be detected, the corresponding operation is stopped, thereby further improving the safety of the system's door sealing strip rolling operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic structural diagram of the automatic rolling system for door sealing strips of the present invention;

[0040] Figure 2 It is a schematic diagram of the operation process of the automatic rolling system for door sealing strips of the present invention;

[0041] Figure numerals: 1-six-axis robot; 2-sealing strip rolling and pasting device; 3-3D structured light camera; 4-vehicle door; 5-vehicle door fixing mechanism. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0043] Example

[0044] like Figure 1 and Figure 2 As shown, this embodiment provides a car door sealing strip automatic rolling system based on a 3D structured light camera, including a six-axis robot 1 and a car door fixing mechanism 5, the six-axis robot 1 is connected to an industrial computer, and the movable end of the six-axis robot 1 is fixed with a 3D structured light camera 3 connected to the industrial computer and a sealing strip rolling and pasting device 2;

[0045] After the door 4 hoisted to the designated position is fixed by the door fixing mechanism 5;

[0046] The 3D structured light camera 3 pre-calibrated with the six-axis robot 1 is used to obtain the door point cloud data containing the key points of the door, and the point cloud offset information is obtained according to the door point cloud data and the door point cloud data of the standard position of the door pre-photographed by the 3D structured light camera 3 at the same position;

[0047] The virtual door rolling and pasting trajectory sequence corresponding to the standard door position pre-written into the six-axis robot is adjusted according to the point cloud offset information. The six-axis robot runs using the actual door rolling and pasting trajectory sequence obtained after the adjustment, and the sealing strip is rolled and pasted to the corresponding position of the door through the sealing strip rolling and pasting device 2 set at the movable end.

[0048] In this embodiment, the first door position of the set model fixed by the door fixing mechanism 5 is used as the standard door position, and the process of obtaining the virtual door rolling trajectory sequence corresponding to the standard door position is specifically as follows: a door sealing strip automatic rolling project model is established in the machine vision software (such as Mech-Vision machine vision software), and a six-axis robot base coordinate system is established with the six-axis robot base as the origin; the three-dimensional image of the door is imported into the door sealing strip automatic rolling project model; the movable end of the six-axis robot (here referring to the position of the sealing strip rolling and pasting device 2 and the door rolling contact surface) is controlled to move to multiple key points (RPS holes) in the first door in sequence, and the actual coordinates of the six-axis robot are obtained. The actual coordinates of the six-axis robot are written into the door sealing strip automatic rolling project model as the virtual door key point coordinates, and the door position in the virtual environment is determined; after the door position in the virtual environment is determined, the virtual door rolling trajectory sequence corresponding to the standard door position is obtained, wherein the position coordinates of each trajectory point in the virtual door rolling trajectory sequence are set vertically to fit the door rolling contact surface.

[0049] The machine vision software pre-stores the door sealing strip automatic rolling project models corresponding to multiple different types of doors, and automatically calls the pre-stored door sealing strip automatic rolling project models corresponding to the doors according to the door models.

[0050] Next, the automatic rolling system for the vehicle door sealing strip of this embodiment is introduced in detail.

[0051] 1. Door fixing mechanism

[0052] The door fixing mechanism 5 includes a frame, multiple servo modules, and a cylinder connected to the servo module. The servo module controls the cylinder to move and clamp the door vertically in four directions. In this embodiment, the door positioning and fixing mechanism can also adopt other solutions to fix the door vertically and firmly.

[0053] 2. 3D structured light camera

[0054] The 3D structured light camera 3 is installed on the sixth axis flange of the six-axis robot 1, and its parameters are set as follows:

[0055] Working distance 500-1000mm, near-end market 370*240mm, far-end field of view 800*450mm, ensuring at most 2 photographs to collect point clouds of the main RPS holes (at least 3) of the door panel; resolution 1920×1200, Z-direction single-point repeatability 0.05mm@1.0m, VDI / VDE measurement accuracy 0.1mm@1.0m, typical acquisition time 0.3~0.6s, light source is blue LED (459nm, RG2).

[0056] The six-axis robot 1 and the 3D structured light camera 3 are calibrated using the hand-eye calibration method based on Eye-In-Hand to obtain the coordinate conversion relationship between the active end (hand) of the six-axis robot 1 and the 3D structured light camera 3 (eye). The process involves four coordinate systems, the base (Base) coordinate system, the active end (End) coordinate system, the camera (Camera) coordinate system, and the visual calibration board (Board) coordinate system.

[0057] like Figure 2 As shown in the figure, for the eye-in-hand calibration method based on Eye-In-Hand, for any two positions of the robot during movement, the following formula holds true:

[0058]

[0059] In the formula, labels 1 and 2 correspond to two postures respectively. Represents the transformation matrix of the Base coordinate system compared to the End coordinate system. Represents the transformation matrix of the End coordinate system compared to the Camera coordinate system. Represents the transformation matrix of the Camera coordinate system compared to the Object coordinate system.

[0060] After transformation, we can get:

[0061]

[0062] Since the position of the camera and the activity end remains unchanged,

[0063] Simplified to: A*X=X*B, solve this matrix equation, the unknown matrix It's the relationship between hand and eye.

[0064] In this embodiment, a 3D structured light camera 3 pre-calibrated with the six-axis robot 1 is used to obtain door point cloud data containing door key points, wherein the door point cloud data containing door key points are captured at two angles each time, and the door point cloud data captured each time are spliced ​​into the same coordinate system. The rotation matrix R and the translation vector T are involved. M is the transformation matrix, the rotation matrix R is responsible for the direction transformation of each point in the point cloud, and the translation vector T is responsible for the position transformation of each point in the point cloud. The coordinate system of the calibrated camera at different shooting positions is known, that is, the transformation matrix rotation matrix R and the translation vector T are known. The rotation matrix R is responsible for the direction transformation of each point in the point cloud, and the translation vector T is responsible for the position transformation of each point in the point cloud. Through this transformation matrix, each point in the source point cloud can be mapped to the corresponding position in the target point cloud coordinate system, realizing the splicing of two or even more point clouds.

[0065] In this embodiment, a visual calibration plate for calibrating the six-axis robot 1 and the 3D structured light camera 3 is fixed at the setting position of the door fixing mechanism 5, or the distance of the visual detection calibration plate is close to the actual detection distance of 550-600mm. In this embodiment, the working area is protected from strong light interference, and a light shield is used when necessary.

[0066] In this embodiment, the six-axis robot 1 and the 3D structured light camera 3 are calibrated each time the door model is changed or at set intervals, thereby further improving the system reliability.

[0067] 3. Six-axis robot

[0068] In this embodiment, during the automatic rolling process of the door sealing strip, the movement speed of the six-axis robot is adaptively adjusted according to the shape of the door, specifically:

[0069] From the starting point, according to the first acceleration (for example, 50mm / s 2 ) is accelerated to a first speed (e.g., 250 mm / s) and then runs at a constant speed;

[0070] When the curvature increases and begins to exceed the first threshold (for example, the transition stage between a straight line and an arc), the speed is reduced to the second speed (for example, 200 mm / s);

[0071] When the curvature increases and begins to exceed the second threshold value (arc start stage), the speed is reduced to the third speed (e.g., 150 mm / s);

[0072] When the curvature decreases and begins to be less than the second threshold value (the arc end stage), the speed is increased to the second speed;

[0073] When the curvature decreases and begins to be less than the first threshold (the transition stage between the arc and the straight line), the vehicle is accelerated to the first speed;

[0074] When it is detected that the distance from the starting point is less than the set value, the speed is reduced to the fourth speed (50mm / s), and then it is decelerated to the fifth speed (for example, 4mm / s) according to the second acceleration until the starting point is detected, and then it stops running and the sealing strip is cut off by the cutting mechanism in the sealing strip rolling and pasting device.

[0075] 4. Sealing strip rolling and pasting device

[0076] The sealing strip rolling and pasting device 2 includes a fixing mechanism for fixing the sealing strip rolling and pasting device 2 to the movable end of the six-axis robot, and a feeding mechanism, a buffer mechanism, a stripping mechanism, a discharging mechanism, a rolling mechanism and a cutting mechanism arranged in sequence according to the travel path of the sealing strip;

[0077] The sealing strip with the isolation paper is controlled by the synchronous belt drive, and passes through the feeding mechanism, the buffer mechanism, the peeling mechanism and the discharging mechanism in sequence, and then the sealing strip with the isolation paper peeled off is rolled and bonded to the set position of the car door through the rolling position, and the sealing strip is cut off by the cutting mechanism after one circle of rolling and bonding, and the sealing strip rolling and bonding device is stopped.

[0078] Among them, the rolling mechanism adopts a rolling wheel; the stripping mechanism can adopt a stripping pin, which separates the sealing strip with isolation paper into a sealing strip channel and an isolation paper channel at the discharge mechanism, and the sealing strip channel is rolled onto the door adhesive surface by the rolling wheel.

[0079] In this embodiment, the sealing strip rolling and pasting device 2 is also provided with a safety monitoring and processing module, which specifically includes:

[0080] A speed sensor and an encoder are arranged at the entrance of the feeding mechanism. When an abnormal feeding speed or a single feeding length is detected, the operation of the robot and the sealing strip rolling and pasting device 2 is stopped and an alarm is sounded;

[0081] A speed sensor and an encoder are provided at the outlet of the discharging mechanism. When the discharging speed or the single discharging length is detected to be abnormal, the operation of the robot and the sealing strip rolling and pasting device 2 is stopped and an alarm is sounded;

[0082] A photoelectric sensor for detecting the release paper peeled off the sealing strip is arranged at the outlet of the discharging mechanism. When the release paper cannot be detected, the operation of the robot and the sealing strip rolling and pasting device 2 is stopped and an alarm is sounded.

[0083] In this embodiment, the visual accuracy is 0.5mm, the rolling accuracy is ±1.0mm, and the gap range of the sealing strip stop needs to be controlled between 0.5±0.5mm. The beat requirement is: the door is fixed, the sealing strip is rolled and mounted, the movable end of the six-axis robot is reset, and the door is fixed and reset. The entire cycle is <=40S. The repeat position tolerance of the pasting track of the door sealing strip is ±1mm.

[0084] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An automatic rolling system for door sealing strips based on a 3D structured light camera, comprising a six-axis robot and a door fixing mechanism, characterized in that: The six-axis robot is connected to an industrial computer, and a 3D structured light camera and a sealing strip rolling and pasting device connected to the industrial computer are fixed to the movable end of the six-axis robot; After fixing the door hoisted to the designated position through the door fixing mechanism; The 3D structured light camera pre-calibrated with the six-axis robot is used to obtain the door point cloud data containing the key points of the door, and the point cloud offset information is obtained based on the door point cloud data and the door point cloud data of the standard door position pre-photographed by the 3D structured light camera at the same position; The virtual door rolling and pasting trajectory sequence corresponding to the standard door position pre-written into the six-axis robot is adjusted according to the point cloud offset information. The six-axis robot runs with the actual door rolling and pasting trajectory sequence obtained after the adjustment, and the sealing strip is rolled and pasted to the corresponding position of the door through the sealing strip rolling and pasting device set at the active end.

2. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 1, characterized in that: The first door position of the set model fixed by the door fixing mechanism is taken as the standard door position. The process of obtaining the virtual door rolling trajectory sequence corresponding to the standard door position is as follows: Establish a model for the automatic rolling project of door sealing strips in the machine vision software, and establish the six-axis robot base coordinate system with the six-axis robot base as the origin; Import the 3D image of the car door into the project model of automatic rolling of the door seal strip; Control the movable end of the six-axis robot to move to multiple key points in the first door in sequence, obtain the actual coordinates of the six-axis robot, write the actual coordinates of the six-axis robot as the coordinates of the key points of the virtual door into the door sealing strip automatic rolling project model, and determine the door position in the virtual environment; After the door position in the virtual environment is determined, a virtual door rolling trajectory sequence corresponding to the door standard position is obtained.

3. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 2, characterized in that: The machine vision software pre-stores the door sealing strip automatic rolling project models corresponding to multiple different types of doors, and automatically calls the pre-stored door sealing strip automatic rolling project models corresponding to the doors according to the door models.

4. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 2, characterized in that: The door point cloud data containing door key points includes at least three door key points.

5. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 1, characterized in that: The six-axis robot and the 3D structured light camera are calibrated using a hand-eye calibration method based on Eye-In-Hand.

6. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 5, characterized in that: The six-axis robot and 3D structured light camera are calibrated every time the door model is changed or at set intervals.

7. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 5, characterized in that: The door fixing mechanism is fixed with a visual calibration plate at a set position for calibrating the six-axis robot and the 3D structured light camera.

8. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 1, characterized in that: During the automatic rolling process of the door seal, the robot's movement speed is adaptively adjusted according to the shape of the door, including: Starting from the starting point, the vehicle is accelerated to a first speed according to a first acceleration and then runs at a constant speed; When the curvature increases and begins to exceed the first threshold, the speed is reduced to the second speed; When the curvature increases and begins to exceed the second threshold, the speed is reduced to the third speed; When the curvature decreases and begins to be less than a second threshold, the speed is increased to a second speed; When the curvature decreases and begins to be less than the first threshold, the speed is increased to the first speed; When it is detected that the distance from the starting point is less than the set value, the speed is reduced to the fourth speed, and then it is decelerated to the fifth speed according to the second acceleration until the starting point is detected and then it stops running.

9. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 1, characterized in that: The sealing strip rolling and pasting device comprises a fixing mechanism for fixing the sealing strip rolling and pasting device to the movable end of the six-axis robot, and a feeding mechanism, a buffer mechanism, a stripping mechanism, a discharging mechanism, a rolling mechanism and a cutting mechanism which are sequentially arranged according to the travel path of the sealing strip; The sealing strip with the isolation paper passes through the feeding mechanism, the buffer mechanism, the peeling mechanism and the discharging mechanism in sequence, and then the sealing strip with the isolation paper peeled off is rolled and bonded to the set position of the car door through the rolling position. After one circle of rolling and bonding, the adhesive strip is cut off by the cutting mechanism, and the sealing strip rolling and bonding device is stopped.

10. The automatic rolling system for door sealing strips based on a 3D structured light camera according to claim 9, characterized in that: The sealing strip rolling and pasting device also includes: A speed sensor and an encoder are provided at the entrance of the feeding mechanism, and when an abnormal feeding speed or single feeding length is detected, the operation is stopped; and / or A speed sensor and an encoder are provided at the outlet of the discharging mechanism, and when an abnormal discharging speed or single discharging length is detected, the mechanism stops running; and / or A photoelectric sensor for detecting the release paper peeled off the sealing strip is arranged at the outlet of the discharging mechanism. When the release paper cannot be detected, the operation is stopped.

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