A truss workpiece positioning method, controller and storage medium

Abstract

The application discloses a truss workpiece positioning method applied to a truss workpiece positioning device, and the device comprises a first laser sensor. The method comprises the following steps: acquiring a plurality of laser lines detected by the first laser sensor on the truss workpiece, each laser line is associated with a rotation angle of the truss workpiece, each laser line comprises a plurality of laser point clouds, and each laser point cloud is associated with a first coordinate and a second coordinate; determining a step point cloud set of each laser line based on the first coordinate; determining a target rotation angle of the truss workpiece according to the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line; and positioning the truss workpiece according to the target rotation angle. The truss workpiece is positioned by using the step property of the one-dimensional coordinate corresponding to the direction perpendicular to the length direction of the truss workpiece in each laser line, so that the data processing difficulty is reduced, the operation efficiency is improved, the structure is simple, and flexible production is facilitated.

Description

Technical Field

[0001] This application relates to the field of engineering machinery, and specifically to a method, controller and storage medium for truss workpiece positioning. Background Technology

[0002] In the field of engineering machinery, the assembly of large truss structures is generally difficult to automate and automatize, especially the assembly of typical pipe-to-pipe intersecting truss structures, which has always been done manually. This method requires a high degree of human intervention and at least two workers to work together. The entire assembly process relies heavily on human experience, making it complex and inefficient. In the current field of automated assembly, for the assembly of workpieces with fixed installation positions and angles, such as pipe-to-pipe intersecting truss assembly, in order to align the intersecting lines at both ends of the web tube with the main circular tube, there is a fixed positional relationship between the web tube and the main circular tube. Since the robot's trajectory is fixed, it is necessary to ensure the consistency of the robot's gripping position. Currently, there are generally two methods to ensure the consistency of the workpiece position: one is to design fixed tooling, with one tooling designed for each type of workpiece, and different workpieces corresponding to different robot paths; the other is intelligent flexibility, which uses sensors to intelligently identify the position and type of the workpiece, adjust the workpiece position to be consistent, and then perform intelligent gripping and placement.

[0003] The existing methods for determining the gripping position of a robot by locating the truss workpiece are computationally intensive and time-consuming, impacting production efficiency. Overall control accuracy is affected by the accuracy of the algorithm and the precision of the mechanism's operation. Therefore, the existing methods for determining the gripping position of the truss workpiece are complex and costly, thus affecting production efficiency. Summary of the Invention

[0004] The purpose of this application is to provide a method, controller, and storage medium for locating truss workpieces, in order to solve the problems of complex process and high cost in the existing methods for determining the gripping position of truss workpieces.

[0005] To achieve the above objectives, a first aspect of this application provides a method for locating truss workpieces, and an apparatus for locating truss workpieces, the apparatus including a first laser sensor, the method comprising:

[0006] Multiple laser lines detected by the first laser sensor on the truss workpiece are obtained. The laser lines are parallel to the length direction of the truss workpiece and surround the truss workpiece. Each laser line is associated with the rotation angle of the truss workpiece. Each laser line includes multiple laser point clouds. The laser point clouds are associated with a first coordinate and a second coordinate. The first coordinate is the coordinate in the direction perpendicular to the length direction of the truss workpiece, and the second coordinate is the coordinate in the length direction of the truss workpiece.

[0007] Based on the first coordinate, determine the set of step point clouds for each laser line;

[0008] The target rotation angle of the truss workpiece is determined based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line.

[0009] Positioning of the truss workpiece is determined based on the target rotation angle.

[0010] In this embodiment of the application, determining the step point cloud set for each laser line based on the first coordinate includes:

[0011] Density clustering is performed on the first coordinates of each laser line to obtain the step points on each laser line;

[0012] The step point cloud set is determined based on the step point. The step point cloud set includes multiple laser point clouds located on the side of the step point where no step occurred and closest to the step point. The multiple laser point clouds are arranged sequentially in the direction towards the step point.

[0013] In this embodiment of the application, the target rotation angle of the truss workpiece is determined based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line, including:

[0014] The rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line are fitted to obtain a two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece.

[0015] Determine the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece.

[0016] In this diagram, the horizontal axis represents the rotation angle associated with each laser line, and the vertical axis represents the second coordinate in the set of step point clouds for each laser line.

[0017] In this embodiment of the application, determining the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece includes:

[0018] The extreme points of the vertical coordinates of each intersection line are selected from the two-dimensional unfolded diagram of multiple intersection lines.

[0019] Obtain multiple rotation angles associated with multiple extreme points on the vertical coordinate;

[0020] The rotation angle that appears most frequently among multiple rotation angles is determined as the target rotation angle.

[0021] In this embodiment of the application, positioning the truss workpiece according to the target rotation angle includes:

[0022] Determine the target point cloud based on the target's rotation angle;

[0023] The truss workpiece is located based on the target point cloud to determine the preset gripping point of the truss workpiece.

[0024] In this embodiment of the application, the target point cloud is the laser point cloud with the maximum or minimum second coordinate on the intersection line of the truss workpiece. Determining the target point cloud based on the rotation angle includes:

[0025] Obtain the extreme points of the vertical coordinate that are related to the target rotation angle from multiple extreme points of the vertical coordinate to form a set of extreme points of the target vertical coordinate;

[0026] The target point cloud is determined based on the maximum or minimum value of the second coordinate in the set of extreme points of the target's vertical coordinate.

[0027] In this embodiment, the device further includes a second laser sensor and a third laser sensor. The second laser sensor emits laser light, and the third laser sensor receives the laser light emitted by the second laser sensor. The preset gripping point is the center point of the truss workpiece. The device locates the truss workpiece based on the target point cloud to determine the preset gripping point of the truss workpiece, including:

[0028] The coordinates of the first laser sensor, the second laser sensor, and the third laser sensor in a preset coordinate system are obtained respectively to obtain the sensor coordinates;

[0029] Determine the second coordinates of the center point based on the sensor coordinates and the second coordinates of the target point cloud;

[0030] Determine the coordinates of the center point based on the second coordinate of the center point;

[0031] Where the second coordinate of the target point cloud is greater than a preset value, the second coordinate of the center point satisfies formula (1):

[0032] E y ={C y -(Δy2-Δy1-|y max |) / 2}; (1)

[0033] When the second coordinate of the target point cloud is less than a preset value, the second coordinate of the center point satisfies formula (2):

[0034] E y ={C y -(Δy2-Δy1+|y max |) / 2}; (2)

[0035] Among them, E y C is the second coordinate of the center point. yLet y1 be the second coordinate of the second laser sensor, Δy2 be the difference between the second coordinates of the second laser sensor and the third laser sensor, and Δy1 be the difference between the second coordinates of the first laser sensor and the third laser sensor. max The second coordinate of the target point cloud.

[0036] A second aspect of this application provides a device for locating truss workpieces, comprising:

[0037] The laser line acquisition module is configured to acquire multiple laser lines detected by the first laser sensor on the truss workpiece.

[0038] The step point cloud set determination module is configured to determine the step point cloud set for each laser line based on the first coordinate.

[0039] The target rotation angle determination module is configured to determine the target rotation angle of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line.

[0040] The truss workpiece positioning module is configured to position the truss workpiece according to the target rotation angle.

[0041] A third aspect of this application provides a controller, comprising:

[0042] The memory is configured to store instructions; and

[0043] The processor is configured to retrieve instructions from memory and, when executing the instructions, to implement the aforementioned method for truss workpiece positioning.

[0044] A fourth aspect of this application provides a machine-readable storage medium storing instructions for causing a machine to perform the above-described method for truss workpiece positioning.

[0045] The above technical solution first obtains multiple laser lines detected by a laser sensor on a truss workpiece. Then, based on the coordinates of each laser point on the laser line in the direction perpendicular to the length direction of the truss workpiece, a set of step points for each laser line is determined. The target rotation angle of the truss workpiece is determined by the rotation angle associated with each laser line and the second coordinate in the set of step points for each laser line. Finally, the truss workpiece is positioned based on the target rotation angle. This application obtains multiple laser lines by scanning the truss workpiece with a laser sensor and associates the rotation angle with each laser line. Then, it uses the step property of the corresponding one-dimensional coordinates in the direction perpendicular to the length direction of the truss workpiece in each laser line to determine the set of step points for each laser line. The target rotation angle of the truss workpiece is determined based on the set of step points, and finally, the truss workpiece is positioned based on the target rotation angle. This reduces the difficulty of data processing, improves computational efficiency, and has a simple structure, which is conducive to flexible production.

[0046] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0047] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings:

[0048] Figure 1 A flowchart illustrating a method for locating a truss workpiece according to an embodiment of this application;

[0049] Figure 2 A schematic diagram of the structure of a truss workpiece positioning device provided in an embodiment of this application;

[0050] Figure 3 A front view of a truss workpiece positioning device provided for a specific embodiment of this application;

[0051] Figure 4 A side view of a truss workpiece positioning device provided for a specific embodiment of this application;

[0052] Figure 5 A schematic diagram of coordinate relationships for a truss workpiece positioning device provided in a specific embodiment of this application;

[0053] Figure 6 A schematic diagram of the working process of the truss workpiece positioning device provided in a specific embodiment of this application;

[0054] Figure 7 A schematic diagram of the algorithm flow for truss workpiece positioning provided in a specific embodiment of this application;

[0055] Figure 8 A two-dimensional unfolded view of the intersection line of a truss workpiece provided in a specific embodiment of this application;

[0056] Figure 9 This is a structural block diagram of a controller provided in an embodiment of this application.

[0057] Explanation of reference numerals in the attached figures

[0058] 1. Grappling robot with 2-line laser sensor

[0059] 3 Truss workpiece 4 Workpiece support platform

[0060] 5 drive rollers; 6-point laser sensor receiver.

[0061] 7. Drive the trolley with 8 laser sensor transmitters.

[0062] 9 Infrared sensor 10 Workpiece rotation mechanism Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0064] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0065] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0066] Figure 1 This is a flowchart illustrating a method for locating a truss workpiece according to an embodiment of this application. Figure 1 As shown in the figure, this application provides a method for locating truss workpieces, and an apparatus for locating truss workpieces, the apparatus including a first laser sensor, the method including the following steps:

[0067] Step 101: Obtain multiple laser lines detected by the first laser sensor on the truss workpiece. The laser lines are parallel to the length direction of the truss workpiece and surround the truss workpiece. Each laser line is associated with the rotation angle of the truss workpiece. Each laser line includes multiple laser point clouds. The laser point clouds are associated with a first coordinate and a second coordinate. The first coordinate is the coordinate in the direction perpendicular to the length direction of the truss workpiece, and the second coordinate is the coordinate in the length direction of the truss workpiece.

[0068] Step 102: Based on the first coordinate, determine the set of step point clouds for each laser line;

[0069] Step 103: Determine the target rotation angle of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate in the set of step points of each laser line.

[0070] Step 104: Locate the truss workpiece according to the target rotation angle.

[0071] This application first acquires multiple laser lines detected by a laser sensor on a truss workpiece. Then, based on the coordinates of each laser point on the laser line in the direction perpendicular to the length direction of the truss workpiece, a step point cloud set for each laser line is determined. The target rotation angle of the truss workpiece is determined by the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line. Finally, the truss workpiece is positioned based on the target rotation angle. This application obtains multiple laser lines by scanning the truss workpiece with a laser sensor and associates the rotation angle with each laser line. Then, it uses the step property of the corresponding one-dimensional coordinates in the direction perpendicular to the length direction of the truss workpiece in each laser line to determine the step point cloud set of each laser line. The target rotation angle of the truss workpiece is determined based on the step point cloud set, and finally, the truss workpiece is positioned based on the target rotation angle. This reduces the data processing difficulty, improves the computational efficiency, and has a simple structure, which is conducive to flexible production.

[0072] In the embodiments of this application, a truss can be a geometrically invariant structure composed of straight bars. A truss generally includes straight bars enclosing triangular or other shaped units. Truss members primarily bear axial tensile or compressive forces, thus fully utilizing the strength of the material. For larger spans, it can save material compared to solid-web beams, reducing self-weight and increasing stiffness. In some examples, a truss can be a standard section, a lifting mechanism, or other steel structures with guiding or supporting functions.

[0073] Truss components refer to the parts that make up a truss structure, such as pipes or structural steel that form a truss. The pipes can be round, square, or have other cross-sectional shapes. For simplicity, this embodiment will primarily use a round pipe as an example. Using some examples, a truss contains a main round pipe and web pipes, with the end of the web pipe connecting to the main round pipe being an irregular port.

[0074] In this embodiment, the truss workpiece can refer to a circular tube with irregular ends, or it can be a box structure or other structures applicable to the truss positioning method of this application. If manual assembly is used for truss structure assembly, the production efficiency is too low; therefore, automated assembly is necessary. In the current field of automated truss structure assembly, especially for truss workpieces with fixed installation angles and positions, such as the assembly of pipe intersection lines, a fixed positional relationship exists between the web tube and the main tube in order to align the intersection lines at both ends of the web tube with the main circular tube. Since the robot's trajectory is fixed, it is necessary to ensure the consistency of the robot's gripping position.

[0075] In this embodiment, the truss workpiece positioning device may include a first laser sensor. The first laser sensor emits a laser beam towards the truss workpiece to acquire point cloud data of each laser point hitting the surface of the truss workpiece. Preferably, the laser emitted by the first laser sensor can be a line laser. After the truss workpiece falls into a specific position in the truss workpiece positioning device, the first laser sensor starts working and emits a laser line towards the truss workpiece. This laser line is parallel to the length direction of the truss workpiece. Taking a cylindrical truss workpiece as an example, the laser line emitted by the first laser sensor is parallel to the axis of the cylindrical truss workpiece. In one example, the first laser sensor can be a line laser sensor. The first laser sensor can also be other sensors capable of detecting spatial coordinates, such as a visual area array camera.

[0076] To ensure that the entire surface of the truss workpiece can be scanned by the first laser sensor, in one example, after the truss workpiece falls into a specific position in the truss workpiece positioning device, the first laser sensor can be fixedly installed at any position parallel to the length direction of the truss workpiece and surrounding it, emitting laser lines towards the truss workpiece. Then, the truss workpiece is controlled to rotate, allowing the first laser sensor to scan the entire tube of the truss workpiece, obtaining multiple laser lines around the truss workpiece. In another example, the truss workpiece can be fixed in a specific position, and the first laser sensor can be controlled to scan around the truss workpiece to obtain multiple laser lines around it.

[0077] In this embodiment, the truss workpiece positioning device may include a robotic arm, which is mainly used to grasp the truss workpiece. To ensure the consistency of the grasping position of all truss workpieces, for each web truss workpiece, the highest point at the intersection line of its irregular port can be rotated to the same position in the truss workpiece positioning device, such as the position farthest from the horizontal plane or the position of the linear laser emitted by the fixedly installed first laser sensor. Since each laser line obtained by the first laser sensor contains a laser point cloud of a point on the intersection line of the truss workpiece, a rotation angle can be associated with each laser line. This rotation angle refers to the rotation angle of the truss workpiece when the first laser sensor is fixedly installed or the rotation angle of the first laser sensor when the truss workpiece is stationary. Furthermore, the point cloud data of the truss workpiece can be processed to determine the target position for the robotic arm to grasp the truss workpiece. By setting the grasping position of the intersection line of the irregular port of the truss workpiece to be consistent, the consistency of the grasping position of the robotic arm for different types of truss workpieces can be ensured, which is beneficial for the subsequent assembly of the truss workpieces and enables flexible production.

[0078] In this embodiment of the application, the target rotation angle of the truss workpiece refers to the angle that the highest point of the irregular port of the truss workpiece needs to rotate from the actual position to the target position. The actual position refers to the position of the highest point of the irregular port of the truss workpiece after it falls into the workpiece support platform, and the target position refers to the position of the highest point of the irregular port of the truss workpiece when the robot grabs the truss workpiece.

[0079] Specifically, the first laser sensor can acquire multiple laser lines surrounding the truss workpiece. Each laser line consists of multiple laser points, and the point cloud data of each laser point includes a first coordinate and a second coordinate in the first laser sensor coordinate system, as well as the rotation angle associated with the laser line containing that laser point. The first coordinate is the coordinate in a first direction in the first laser sensor coordinate system, and the second coordinate is the coordinate in a second direction in the first laser sensor coordinate system. The first direction in the first laser sensor coordinate system can be a direction perpendicular to the length direction of the truss workpiece, and the second direction can be a direction parallel to the length direction of the truss workpiece and parallel to the horizontal plane.

[0080] Because the ports of the truss workpiece are irregular, each laser line shares the characteristic that its front laser strikes the surface of the truss workpiece, while its rear laser line is either suspended in the air or strikes the workpiece surface. It is understandable that the first-direction coordinates of each laser line will exhibit a step change at the intersection line of the truss workpiece. Therefore, the step change in the first-direction coordinates of each laser line can be used to locate the truss workpiece, i.e., determine the gripping position of the robot arm. Using the step change in the first-direction coordinates of each laser line, the step point cloud set of each laser line can be determined first. With the step point cloud set determined, the intersection line of the truss workpiece is obtained by fitting the rotation angle associated with each laser line and the second coordinate data in the step point cloud set. The target rotation angle is then determined based on the intersection line of the truss workpiece. Furthermore, the target rotation angle of the truss workpiece is determined. With the target rotation angle of the truss workpiece determined, the truss workpiece is located to determine the gripping position of the robot arm.

[0081] In this embodiment of the application, step 102, determining the set of step point clouds for each laser line based on the first coordinates, may include:

[0082] Density clustering is performed on the first coordinates of each laser line to obtain the step points on each laser line;

[0083] The step point cloud set is determined based on the step point. The step point cloud set includes multiple laser point clouds located on the side of the step point where no step occurred and closest to the step point. The multiple laser point clouds are arranged sequentially in the direction towards the step point.

[0084] In this embodiment, the first coordinate is a coordinate perpendicular to the length direction of the truss workpiece. For example, for a cylindrical truss workpiece, the length direction is the axial direction, and the first coordinate is a coordinate perpendicular to the axial direction of the truss workpiece. Since the direction of the laser line emitted by the first laser sensor is parallel to the length direction of the truss workpiece, and the end port of the truss workpiece is an irregular port, the common feature of each laser line is that the front laser line hits the surface of the truss workpiece, and the rear laser line is either suspended or hits the surface of the workpiece. In this case, the first coordinate of each laser line will step at the intersection line of the truss workpiece. Therefore, the step point of the first coordinate of each laser line can be determined by utilizing the step property of the first coordinate of each laser line. Preferably, to prevent the randomness of the data, the step point cloud of each laser line can be determined by the step point on each laser line to ensure the accuracy of the result.

[0085] In one example, taking the case where the first laser sensor is disposed above the truss workpiece, at this time, the first coordinate in the point cloud data obtained by scanning the truss workpiece with the first laser sensor is the z coordinate in the direction perpendicular to the horizontal plane. By scanning the truss workpiece with the first laser sensor, n laser lines are obtained. Each laser line includes m laser point clouds. The set formed by the first coordinates of the m laser point clouds on the n laser lines is:

[0086] U

[0087] Utilize the property that the z coordinate has a step on each line laser to perform a density clustering DBSCAN algorithm C=(D, e, mint) processing on each n set in the (b = 1, 2, 3...n) set, and the following can be obtained:

[0088]

[0089]

[0090]

[0091] The data of class is the coordinate set formed by the non-step of the z coordinate on each laser line, The data of class is the set formed by the step of the z coordinate on each laser line. C n is the data set for distinguishing the first coordinate before the step point and the first coordinate after the step for each laser line among the n laser lines. At this time, the first coordinate of the step point on each laser line can be determined as

[0092] To prevent data spottiness, determine the step point cloud set corresponding to each laser line through the step points on each laser line to ensure the accuracy of the result. Screen out the last p (1 < p < k) z coordinates in the set of the n line lasers to form the set Z C :

[0093]

[0094] Z C The z coordinate on each line laser in the set is the first coordinate of the last p laser point clouds where each laser line hits the workpiece surface. Then, through Z <00000 !4>screen out the corresponding second coordinate set Y among the n laser lines C :

[0095]

[0096] According to Z C and YC The data of the first and second coordinates of each laser line are combined with the rotation angle associated with each laser line to obtain the step point cloud set.

[0097] By utilizing the step properties of the first coordinate of each laser line to perform density clustering on the first coordinate of each laser line, the step points on each laser line are obtained. Then, the step point cloud set is determined based on the step points, which reduces the difficulty of data processing, improves the computational efficiency, prevents the randomness of data, and improves the accuracy of measurement results.

[0098] In this embodiment of the application, step 103, determining the target rotation angle of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line, may include:

[0099] The rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line are fitted to obtain a two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece.

[0100] Determine the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece.

[0101] In this diagram, the horizontal axis represents the rotation angle associated with each laser line, and the vertical axis represents the second coordinate in the set of step point clouds for each laser line.

[0102] In this embodiment, the target rotation angle of the truss workpiece refers to the angle required to rotate the highest point of the irregular port of the truss workpiece from its actual position to its target position. The actual position refers to the location of the highest point of the irregular port of the truss workpiece after it falls onto the workpiece support platform, and the target position refers to the location of the highest point of the irregular port of the truss workpiece when the robot grips the truss workpiece. To ensure consistency in gripping positions for different truss workpieces, the irregular ports of the truss workpieces can be adjusted to the target position before gripping the truss workpiece. In one example, the target position of the highest point of the irregular port of the truss workpiece can be the position corresponding to the origin of the workpiece rotation mechanism; that is, in the robot's coordinate system, the coordinates of the highest point of the irregular port of the truss workpiece and the origin of the workpiece rotation mechanism are the same in both directions. For example, a three-dimensional coordinate system established with the origin of the manipulator includes three directions: x, y, and z. The x-coordinate is perpendicular to the length direction of the truss workpiece and parallel to the horizontal plane, the y-coordinate is parallel to the length direction of the truss workpiece and parallel to the horizontal plane, and the z-coordinate is perpendicular to the horizontal plane. In this case, under the manipulator coordinate system, the x and z coordinates of the highest point of the irregular port of the truss workpiece are the same as those of the workpiece rotation mechanism.

[0103] Therefore, before gripping the truss workpiece, the controller needs to obtain the target rotation angle of the truss workpiece, rotate the truss workpiece to the target position according to the target rotation angle, and then perform positioning and gripping of the truss workpiece.

[0104] In this embodiment, the target rotation angle can be determined by the target step point cloud set of the truss workpiece. Using the second coordinate data Y from the target step point cloud set determined in the coordinate system of the first laser sensor itself as the ordinate, and the rotation angle α corresponding to the second coordinate data as the abscissa, a (α-Y) two-dimensional coordinate system is formed. Further fitting processing is performed to fit the graphic of the top of the truss workpiece rotating one full circle, thereby obtaining a two-dimensional unfolded diagram of multiple intersecting lines, further determining the target rotation angle.

[0105] For example, the second coordinate set in the target step point cloud set is Y C Y C Extract the second coordinate relative to the subscript to obtain There are a total of p data sets. Each data set contains n data points corresponding to a rotation angle. Therefore, ... By fitting n data points to their corresponding rotation angles, a two-dimensional unfolded diagram of the intersection line can be obtained. Similarly, for... By fitting all the lines, a two-dimensional unfolded diagram of p intersection lines can be obtained. The rotation angle corresponding to the maximum value of y for each intersection line in the two-dimensional unfolded diagram is selected, and the target rotation angle is determined based on this.

[0106] By fitting the target step point cloud set, a two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece is obtained, which further determines the target rotation angle. This helps to prevent data randomness, improves accuracy, reduces the difficulty of data processing, improves computational efficiency, and saves costs.

[0107] In this embodiment of the application, determining the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece may include:

[0108] The extreme points of the vertical coordinates of each intersection line are selected from the two-dimensional unfolded diagram of multiple intersection lines.

[0109] Obtain multiple rotation angles associated with multiple extreme points on the vertical coordinate;

[0110] The rotation angle that appears most frequently among multiple rotation angles is determined as the target rotation angle.

[0111] Specifically, in the first laser sensor coordinate system, the highest point of the intersection line of the truss workpiece is the laser point cloud with the largest or smallest second coordinate among all laser point clouds on the intersection line of the truss workpiece. Since the ordinate of the two-dimensional unfolded diagram of multiple intersection lines is the second coordinate of the laser point cloud of the intersection line of the truss workpiece in the first laser sensor coordinate system, the extreme points of the ordinate of each intersection line can be selected from the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece, and the two-dimensional coordinate set of the extreme points of each intersection line can be obtained. Since theoretically, the rotation angle corresponding to the highest point of multiple intersection lines is the same, in order to prevent the randomness of the data and ensure the accuracy of the results, the rotation angle that appears most frequently in the set can be selected and determined as the target rotation angle.

[0112] In this embodiment of the application, step 104, positioning the truss workpiece according to the target rotation angle, may include:

[0113] Determine the target point cloud based on the target's rotation angle;

[0114] The truss workpiece is located based on the target point cloud to determine the preset gripping point of the truss workpiece.

[0115] Specifically, the target point cloud is the point cloud data of the highest point of the irregular port of the truss workpiece. After determining the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of the multiple intersecting lines obtained by fitting, the second coordinates of the target point cloud can be further obtained based on the two-dimensional unfolded diagram of the truss workpiece and the target rotation angle. Based on the second coordinates and the target rotation angle, the values ​​of the target point cloud can be determined. The preset gripping point of the truss workpiece refers to the gripping position when gripping the truss workpiece. In one example, the preset gripping point of the truss workpiece can be the center point of the truss workpiece. In this way, the consistency of the gripping position for different models of truss workpieces can be achieved, and the calculation process is simple, the data processing difficulty is low, and the accuracy is high. After determining the target point cloud of the truss workpiece, that is, the point cloud data of the highest point of the irregular port of the truss workpiece, the controller can determine the gripping position coordinates for gripping the truss workpiece through the target point cloud and the coordinate data of each component in the truss workpiece positioning device.

[0116] In this embodiment, the target point cloud is the laser point cloud with the maximum or minimum second coordinate on the intersection line of the truss workpiece. Determining the target point cloud based on the rotation angle may include:

[0117] Obtain the extreme points of the vertical coordinate that are related to the target rotation angle from multiple extreme points of the vertical coordinate to form a set of extreme points of the target vertical coordinate;

[0118] The target point cloud is determined based on the maximum or minimum value of the second coordinate in the set of extreme points of the target's vertical coordinate.

[0119] Specifically, the second coordinate is the coordinate in the first laser sensor coordinate system along a direction parallel to the length direction of the truss workpiece. The target point cloud is the laser point cloud with the maximum or minimum second coordinate on the intersection line of the truss workpiece, i.e., the point cloud data of the highest point of the irregular port of the truss workpiece. To prevent data randomness and ensure the accuracy of the detection results, the extreme points corresponding to the rotation angle can be grouped into a set, i.e., the target ordinate extreme point set. In one example, the second coordinate of the highest point of the intersection line can be either the maximum or minimum value. Therefore, based on the direction of the second coordinate axis in the first laser sensor coordinate system, the size relationship of the highest point of the intersection line in the set is determined. Then, the maximum or minimum value of the second coordinate in the target ordinate extreme point set is determined as the second coordinate of the target point cloud. The specific value of the target point cloud is determined based on the second coordinate of the target point cloud.

[0120] In this embodiment, the device further includes a second laser sensor and a third laser sensor. The second laser sensor emits laser light, and the third laser sensor receives the laser light emitted by the second laser sensor. The preset gripping point is the center point of the truss workpiece. Positioning the truss workpiece based on the target point cloud to determine the preset gripping point may include:

[0121] The coordinates of the first laser sensor, the second laser sensor, and the third laser sensor in a preset coordinate system are obtained respectively to obtain the sensor coordinates;

[0122] Determine the second coordinates of the center point based on the sensor coordinates and the second coordinates of the target point cloud;

[0123] Determine the coordinates of the center point based on the second coordinate of the center point;

[0124] Where the second coordinate of the target point cloud is greater than a preset value, the second coordinate of the center point satisfies formula (1):

[0125] E y ={C y -(Δy2-Δy1-|y max |) / 2}; (1)

[0126] When the second coordinate of the target point cloud is less than a preset value, the second coordinate of the center point satisfies formula (2):

[0127] E y ={C y -(Δy2-Δy1+|y max |) / 2}; (2)

[0128] Among them, E y C is the second coordinate of the center point. yLet y1 be the second coordinate of the second laser sensor, Δy2 be the difference between the second coordinates of the second laser sensor and the third laser sensor, and Δy1 be the difference between the second coordinates of the first laser sensor and the third laser sensor. max The second coordinate of the target point cloud.

[0129] Specifically, the second and third laser sensors are respectively located at both ends of the truss workpiece, and the second coordinate of the second laser sensor in the robot's coordinate system is the same as the second coordinate of the first end of the truss workpiece, which is the end furthest from the first laser sensor. Since the second coordinate positions of the first, second, and third laser sensors in the robot's coordinate system remain unchanged, the second coordinate of the center point of the truss workpiece can be determined by combining the first, second, and third laser sensors with the target point cloud data. This further determines the coordinate position of the center point of the truss workpiece in the robot's coordinate system, thereby controlling the robot to grasp the truss workpiece and achieving consistency in the grasping position of the truss workpiece.

[0130] Figure 2 This is a schematic structural diagram of a truss workpiece positioning device provided in an embodiment of this application. Figure 2 As shown, this application embodiment provides a device for locating the odor of truss workpieces, comprising:

[0131] The laser line acquisition module 210 is configured to acquire multiple laser lines detected by the first laser sensor on the truss workpiece;

[0132] The step point cloud set determination module 220 is configured to determine the step point cloud set for each laser line based on the first coordinate;

[0133] The target rotation angle determination module 230 is configured to determine the target rotation angle of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate in the set of step points of each laser line.

[0134] The truss workpiece positioning module 240 is configured to position the truss workpiece according to the target rotation angle.

[0135] Specifically, the laser line acquisition module 210 can acquire multiple laser lines surrounding the truss workpiece through the first laser sensor. Each laser line consists of multiple laser points, and the point cloud data of each laser point includes a first coordinate and a second coordinate in the first laser sensor coordinate system, as well as the rotation angle associated with the laser line to which the laser point is located. The first coordinate is the coordinate in a first direction in the first laser sensor coordinate system, and the second coordinate is the coordinate in a second direction in the first laser sensor coordinate system. The first direction in the first laser sensor coordinate system can be a direction perpendicular to the length direction of the truss workpiece, and the second direction can be a direction parallel to the length direction of the truss workpiece and parallel to the horizontal plane.

[0136] Because the ports of the truss workpiece are irregular, each laser line has the characteristic that the front laser line hits the surface of the truss workpiece, while the rear laser line is either suspended in the air or hits the workpiece surface. It is understandable that the first direction coordinate of each laser line will experience a step change at the intersection line of the truss workpiece. Therefore, the step change in the first direction coordinate of each laser line can be used to locate the truss workpiece, i.e., determine the gripping position of the robot arm on the truss workpiece. The step point cloud set determination module 220 can first determine the step point cloud set of each laser line using the step change in the first direction coordinate of each laser line. With the step point cloud set determined, the target rotation angle determination module 230 fits the intersection line of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate data in the step point cloud set, and determines the target rotation angle based on the intersection line of the truss workpiece. Then, the target rotation angle of the truss workpiece is determined. Once the target rotation angle of the truss workpiece is determined, the truss workpiece positioning module 240 positions the truss workpiece to determine the gripping position of the robot arm.

[0137] Figure 3 This is a front view of a truss workpiece positioning device provided for a specific embodiment of this application. Figure 4 This is a side view of a truss workpiece positioning device according to a specific embodiment of this application. In this specific embodiment, the truss workpiece positioning method is applied to, for example... Figure 3 and Figure 4 The device shown is for locating a truss workpiece. This device may include a gripper robot 1, a line laser sensor 2, a truss workpiece 3, a workpiece support platform 4, drive rollers 5, a point laser sensor receiver 6, a drive trolley 7, a point laser sensor transmitter 8, an infrared sensor 9, and a workpiece rotation mechanism 10. The line laser sensor 2 is the first laser sensor, the point laser sensor receiver 6 is the third laser sensor, and the point laser reflector 8 is the second laser sensor.

[0138] Figure 5 This is a schematic diagram of the coordinate relationship of a truss workpiece positioning device provided for a specific embodiment of this application. Figure 5 As shown, during device installation, the gripper robot 1 calibrates the line laser sensor 2, the point laser sensor receiver 6, the point laser sensor transmitter 8, the infrared sensor 9, and the workpiece rotation mechanism center 10, respectively, and obtains the following positional relationships:

[0139] 1. The positional relationship between the coordinate system of the line laser sensor 2 and the base coordinate system of the gripper robot 1 is as follows:

[0140] 2. The positional relationship between the 6-coordinate system of the point laser sensor receiver and the 1-base coordinate system of the gripper robot is as follows:

[0141] 3. The positional relationship between the 8-coordinate system of the point laser sensor transmitter and the 1-base coordinate system of the gripper robot is as follows:

[0142] 4. The positional relationship between the coordinate system of infrared sensor 9 and the base coordinate system of gripper robot 1 is as follows:

[0143] 5. The positional relationship between the center point coordinates of the workpiece rotation mechanism 10 and the base coordinates of the gripper robot 1 is as follows:

[0144] 6. The Y-coordinate relationship between the origin coordinate system of the line laser sensor 2 and the coordinate system of the point laser sensor receiver 6 is Δy1 = A. y -B y .

[0145] 7. The Y-coordinate relationship between the point laser sensor transmitter 8 and the point laser sensor receiver 6 is Δy2=C y -B y .

[0146] 8. The Y-coordinate relationship between the point laser sensor transmitter 8 and the infrared sensor 9 is C. y =F y .

[0147] 9. The distance relationship between the origin coordinates of the line laser sensor 2 and the origin coordinates Z of the workpiece rotation mechanism 10 is Δz1 = A. Z -G z .

[0148] 10. The center coordinates of the gripper robot 1 gripping the truss workpiece are:

[0149] Figure 6 This is a schematic diagram of the working process of a truss workpiece positioning device provided in a specific embodiment of this application. Figure 7 This is a schematic diagram of the algorithm flow for truss workpiece positioning provided in a specific embodiment of this application. Figure 6 and Figure 7 As shown, the truss workpiece 3 rolls freely from the ramped platform into the workpiece support platform 4. The drive roller 5 rotates, causing the truss workpiece 3 to move towards the workpiece rotation mechanism 10. When the infrared sensor 9 detects the presence of the workpiece, the drive roller 5 stops rotating, and the workpiece is in place. The three-jaw chuck on the workpiece rotation mechanism 10 clamps the workpiece, and the line laser sensor 2 starts working, reading laser data in real time. Simultaneously, the trolley 7, carrying the line laser sensor 7 and the point laser sensor receiver 6, moves along a straight line towards the workpiece rotation mechanism 10. When the truss workpiece 3 is scanned within the field of view of the line laser sensor 7, the trolley 7 travels to a set distance and then stops, ensuring that the intersection line joint at the top of the truss workpiece 3 is within the field of view of the line laser sensor 2. The line laser sensor 2 is then turned off, and the distance data Δy2 between the point laser sensor receiver 6 and the point laser sensor emitter 8 at the stopping position of the trolley 7 is recorded, thus obtaining the B of the point laser sensor receiver 6. y A coordinate and line laser sensor 2 y coordinate:

[0150] B y =C y -Δy2;

[0151] A y =B y +Δy1.

[0152] The control system controls the line laser sensor 2 and the workpiece rotation mechanism 10 to work synchronously. The line laser sensor 2 collects the laser data after the truss workpiece 3 rotates one revolution at a constant speed. The laser sampling frequency f (Hz) of the line laser sensor 2 and the time t (s) required for the workpiece rotation mechanism 10 to rotate one revolution satisfy the following relationship:

[0153]

[0154] The number n of laser lines obtained by the line laser sensor 2 rotating one revolution satisfies:

[0155] n = f*t.

[0156] The control system algorithm, after data filtering and smoothing, can obtain m (yz) two-dimensional data coordinate points from n line lasers. The y and z coordinates of each line laser are then selected to form a separate set.

[0157]

[0158]

[0159] The laser line direction of the line laser sensor 2 is parallel to the axis of the truss workpiece 3. The unified feature of each line laser is that the front-segment laser line hits the workpiece surface, and the rear-segment laser line is suspended or hits the inner surface of the workpiece. Utilize the property that the z coordinate of the line laser undergoes a step to perform operations on Z n Each in the set (b = 1, 2, 3…n) Perform the density clustering DBSCAN algorithm C=(D, e, mint) on the set to obtain:

[0160]

[0161]

[0162]

[0163] The data of the class is the coordinate set formed when the z coordinate of the line laser does not undergo a step, The data of the class is the set formed when the z coordinate of the line laser undergoes a step. To prevent data occasionality, screen out n line lasers, The last p (1 < p < k) z coordinates in the set form the set Z C , and this z coordinate is the last p coordinate points where each laser line hits the workpiece surface:

[0164]

[0165] And screen out the corresponding Y C coordinates.

[0166]

[0167] Take the rotation angle (0 - 360°) of the rotation mechanism as the abscissa α, and the spacing of the rotation angle of the rotation mechanism is:

[0168]

[0169] Take the filtered Y C coordinate data points in the coordinate system of the line laser sensor 2 itself as the ordinate Y to form the (α - Y) two-dimensional coordinate system

[0170] Figure 8 This is the two-dimensional development diagram of the intersection line of the truss workpiece provided by a specific embodiment of this application. Fit the graph of the top of the truss workpiece 3 rotating one circle to obtain p (1 < p < k) two-dimensional development diagrams of the intersection line, as Figure 8 shown. The control system marks the coordinate point set α - Y where the highest point of the ordinate Y of each intersection line is located:

[0171] [[ID=�5]]

[0172] To determine the consistency of α values ​​in the α-Y set, select the set of Y values ​​corresponding to the most frequent α values. d,e,f∈(1,2,3……p)andd≠e≠f.

[0173] Filter out y max ∈Y n .

[0174] z can be obtained based on coordinate correspondence. max :

[0175] z max For y max The corresponding z-coordinate value in the coordinate system of the line laser sensor 2, z max ∈Z n .

[0176] Where y max The highest point of the intersection line in the laser coordinate system is the location of the truss workpiece 3 after rotating one revolution. ( (The value of α in the α-Y set is the maximum value) represents the angle through which the workpiece rotation mechanism rotates by 10.

[0177] The control system controls the workpiece rotation mechanism 10 to reverse. Place the highest point of the intersection line at the original position.

[0178] And we can determine the y-coordinate of the center point of truss workpiece 3 at this time:

[0179] When y max >0:

[0180] E y ={C y -(Δy2-Δy1+|y max |) / 2};

[0181] When y max <0::

[0182] E y ={C y -(Δy2-Δy1-|y max |) / 2};

[0183] Because the truss workpiece 3 moves linearly along the y-axis, its x and z coordinates remain unchanged, maintaining consistency with the workpiece rotation mechanism 10, i.e., E x =G x E z =G z .

[0184] The coordinates of the gripper robot 1 can then be obtained as follows:

[0185] When the gripper robot 1 grasps the truss workpiece 3, it can intelligently identify the center coordinates of the stringer tube. Furthermore, the highest point of the intersection line of the truss workpiece 3 is always located at the origin of the workpiece rotation mechanism 10.

[0186] The workpiece length L is obtained by calculating |Δy2-Δy1±|y max The outer diameter of the workpiece, d = |Δz1| - |z max By utilizing the workpiece length and outer diameter of the belt, the workpiece model can be determined, and different robot placement programs can be adjusted to achieve intelligent and flexible production.

[0187] The target data can be obtained by filtering the point cloud data. The control accuracy is less affected by the algorithm calculation error. Because the laser is relatively fixed and only performs linear motion, it is also less affected by the accuracy caused by the movement of the mechanism, resulting in high overall accuracy. In addition, by scanning the irregular port of the pipe with a laser, the pipe position can be returned to the correct position, the position of the robotic arm can be corrected, and different types of workpieces can be identified and the placement program can be automatically retrieved, realizing intelligent and flexible production of gripping and placing.

[0188] Figure 9 This is a structural block diagram of a controller provided in an embodiment of this application. Figure 9 As shown in the figure, this application provides a controller that may include:

[0189] Memory 910 is configured to store instructions; and

[0190] The processor 920 is configured to retrieve instructions from memory and, when executing the instructions, to implement the aforementioned method for truss workpiece positioning.

[0191] Specifically, in this embodiment of the application, the processor 920 can be configured to:

[0192] Multiple laser lines detected by the first laser sensor on the truss workpiece are obtained. The laser lines are parallel to the length direction of the truss workpiece and surround the truss workpiece. Each laser line is associated with the rotation angle of the truss workpiece. Each laser line includes multiple laser point clouds. The laser point clouds are associated with a first coordinate and a second coordinate. The first coordinate is the coordinate in the direction perpendicular to the length direction of the truss workpiece, and the second coordinate is the coordinate in the length direction of the truss workpiece.

[0193] Based on the first coordinate, determine the set of step point clouds for each laser line;

[0194] The target rotation angle of the truss workpiece is determined based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line.

[0195] Positioning of the truss workpiece is determined based on the target rotation angle.

[0196] Furthermore, the processor 920 can also be configured as follows:

[0197] Based on the first coordinate, determine the set of step point clouds for each laser line, including:

[0198] Density clustering is performed on the first coordinates of each laser line to obtain the step points on each laser line;

[0199] The step point cloud set is determined based on the step point. The step point cloud set includes multiple laser point clouds located on the side of the step point where no step occurred and closest to the step point. The multiple laser point clouds are arranged sequentially in the direction towards the step point.

[0200] Furthermore, the processor 920 can also be configured as follows:

[0201] Based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line, the target rotation angle of the truss workpiece is determined, including:

[0202] The rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line are fitted to obtain a two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece.

[0203] Determine the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece.

[0204] In this diagram, the horizontal axis represents the rotation angle associated with each laser line, and the vertical axis represents the second coordinate in the set of step point clouds for each laser line.

[0205] Furthermore, the processor 920 can also be configured as follows:

[0206] The target rotation angle of the truss workpiece is determined based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece, including:

[0207] The extreme points of the vertical coordinates of each intersection line are selected from the two-dimensional unfolded diagram of multiple intersection lines.

[0208] Obtain multiple rotation angles associated with multiple extreme points on the vertical coordinate;

[0209] The rotation angle that appears most frequently among multiple rotation angles is determined as the target rotation angle.

[0210] Furthermore, the processor 920 can also be configured as follows:

[0211] Positioning the truss workpiece based on the target rotation angle includes:

[0212] Determine the target point cloud based on the target's rotation angle;

[0213] The truss workpiece is located based on the target point cloud to determine the preset gripping point of the truss workpiece.

[0214] Furthermore, the processor 920 can also be configured as follows:

[0215] The target point cloud is the laser point cloud with the maximum or minimum second coordinate on the intersection line of the truss workpiece. The target point cloud is determined based on the rotation angle, including:

[0216] Obtain the extreme points of the vertical coordinate that are related to the target rotation angle from multiple extreme points of the vertical coordinate to form a set of extreme points of the target vertical coordinate;

[0217] The target point cloud is determined based on the maximum or minimum value of the second coordinate in the set of extreme points of the target's vertical coordinate.

[0218] Furthermore, the processor 920 can also be configured as follows:

[0219] The device also includes a second laser sensor and a third laser sensor. The second laser sensor emits laser light, and the third laser sensor receives the laser light emitted by the second laser sensor. The preset gripping point is the center point of the truss workpiece. The device locates the truss workpiece based on the target point cloud to determine the preset gripping point of the truss workpiece, including:

[0220] The coordinates of the first laser sensor, the second laser sensor, and the third laser sensor in a preset coordinate system are obtained respectively to obtain the sensor coordinates;

[0221] Determine the second coordinates of the center point based on the sensor coordinates and the second coordinates of the target point cloud;

[0222] Determine the coordinates of the center point based on the second coordinate of the center point;

[0223] Where the second coordinate of the target point cloud is greater than a preset value, the second coordinate of the center point satisfies formula (1):

[0224] E y ={C y -(Δy2-Δy1-|y max |) / 2}; (1)

[0225] When the second coordinate of the target point cloud is less than a preset value, the second coordinate of the center point satisfies formula (2):

[0226] E y ={C y -(Δy2-Δy1+|y max |) / 2}; (2)

[0227] Among them, Ey C is the second coordinate of the center point. y Let y1 be the second coordinate of the second laser sensor, Δy2 be the difference between the second coordinates of the second laser sensor and the third laser sensor, and Δy1 be the difference between the second coordinates of the first laser sensor and the third laser sensor. max The second coordinate of the target point cloud.

[0228] This application also provides a machine-readable storage medium storing instructions for causing a machine to perform the above-described method for truss workpiece positioning.

[0229] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0230] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0231] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0232] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0233] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0234] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0235] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0236] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0237] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for locating a truss workpiece, characterized in that, An apparatus for positioning truss workpieces, the apparatus including a first laser sensor, the method comprising: Multiple laser lines detected by the first laser sensor on the truss workpiece are obtained. The laser lines are parallel to the length direction of the truss workpiece and surround the truss workpiece. Each laser line is associated with the rotation angle of the truss workpiece. Each laser line includes multiple laser point clouds. The laser point clouds are associated with a first coordinate and a second coordinate. The first coordinate is the coordinate in the direction perpendicular to the length direction of the truss workpiece, and the second coordinate is the coordinate in the length direction of the truss workpiece. Based on the first coordinates, determine the set of step point clouds for each laser line; The target rotation angle of the truss workpiece is determined based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line. Position the truss workpiece according to the target rotation angle.

2. The method according to claim 1, characterized in that, The determination of the step point cloud set for each laser line based on the first coordinates includes: Density clustering is performed on the first coordinates of each laser line to obtain the step point on each laser line; A set of step point clouds is determined based on the step point. The set of step point clouds includes multiple laser point clouds located on the side of the step point where no step occurred and closest to the step point. The multiple laser point clouds are arranged sequentially in the direction toward the step point.

3. The method according to claim 1, wherein determining the target rotation angle of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line comprises: The rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line are fitted to obtain a two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece. The target rotation angle of the truss workpiece is determined based on the two-dimensional unfolded diagram of the multiple intersection lines of the truss workpiece. Wherein, the horizontal axis of the two-dimensional unfolded diagram is the rotation angle associated with each laser line, and the vertical axis of the two-dimensional unfolded diagram is the second coordinate in the step point cloud set of each laser line.

4. The method according to claim 3, characterized in that, The determination of the target rotation angle of the truss workpiece based on the two-dimensional unfolded diagram of multiple intersection lines of the truss workpiece includes: The extreme points of the vertical coordinates of each intersection line are selected from the two-dimensional unfolded diagram of the multiple intersection lines respectively; Obtain multiple rotation angles associated with multiple extreme points of the ordinate; The rotation angle that appears most frequently among the multiple rotation angles is determined as the target rotation angle.

5. The method according to claim 4, characterized in that, The step of locating the truss workpiece according to the target rotation angle includes: Determine the target point cloud based on the target rotation angle; The truss workpiece is located based on the target point cloud to determine the preset gripping point of the truss workpiece.

6. The method according to claim 5, characterized in that, Determining the target point cloud based on the rotation angle includes: Obtain the extreme points of the vertical coordinates that are associated with the target rotation angle from among the multiple extreme points of the vertical coordinates, so as to form a set of extreme points of the target vertical coordinates; The target point cloud is determined based on the maximum or minimum value of the second coordinate in the set of extreme points of the target ordinate.

7. The method according to claim 5, characterized in that, The device further includes a second laser sensor and a third laser sensor. The second laser sensor is used to emit laser light, and the third laser sensor is used to receive the laser light emitted by the second laser sensor. The preset gripping point is the center point of the truss workpiece. The step of locating the truss workpiece based on the target point cloud to determine the preset gripping point of the truss workpiece includes: The coordinates of the first laser sensor, the second laser sensor, and the third laser sensor in a preset coordinate system are obtained respectively to obtain the sensor coordinates; The second coordinates of the center point are determined based on the sensor coordinates and the second coordinates of the target point cloud. The coordinates of the center point are determined based on the second coordinates of the center point. Wherein, when the second coordinate of the target point cloud is greater than a preset value, the second coordinate of the center point satisfies formula (1): E y ={C y -(△y2-△y1-|y max |) / 2}; (1) When the second coordinate of the target point cloud is less than a preset value, the second coordinate of the center point satisfies formula (2): E y ={C y -(△y2-△y1+|y max |) / 2}; (2) in, y C is the second coordinate of the center point. y Let y1 be the second coordinate of the second laser sensor, Δy2 be the difference between the second coordinates of the second laser sensor and the third laser sensor, and Δy1 be the difference between the second coordinates of the first laser sensor and the third laser sensor. max The second coordinate of the target point cloud.

8. A device for locating truss workpieces, characterized in that, include: The laser line acquisition module is configured to acquire multiple laser lines detected by the first laser sensor on the truss workpiece. The step point cloud set determination module is configured to determine the step point cloud set for each laser line based on the first coordinate. The target rotation angle determination module is configured to determine the target rotation angle of the truss workpiece based on the rotation angle associated with each laser line and the second coordinate in the step point cloud set of each laser line. The truss workpiece positioning module is configured to position the truss workpiece according to the target rotation angle.

9. A controller, characterized in that, include: The memory is configured to store instructions; as well as The processor is configured to retrieve the instructions from the memory and, when executing the instructions, to implement the method for truss workpiece positioning according to any one of claims 1 to 7.

10. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to perform the method of truss workpiece positioning according to any one of claims 1 to 7.

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