Bamboo fixed-section and section-avoiding saw cutting method and device

Abstract

The method comprises the steps that an industrial camera is started to capture a bamboo image, bamboo joint position data is obtained according to the image, whether knot avoiding calculation is needed or not is judged according to the position data, a knot avoiding calculation result is obtained, and the bamboo position is adjusted for sawing. The automatic bamboo sawing machine adopting the fixed-length section-avoiding sawing method for the bamboo wood meets the current primary processing production requirement, it can be guaranteed that no bamboo joints exist within 25 mm at the two ends of each bamboo section, the section-avoiding success rate reaches 100%, meanwhile, the average processing efficiency reaches 30.12 m / min and is about 3.77 times that of manual work, and the labor cost is reduced by 50% or above. By means of the method, the bamboo primary processing industry can be effectively promoted to develop towards the large-scale, automatic and intelligent direction.

Description

Technical Field

[0001] The present application relates to the technical field of bamboo sawing, and in particular to a method and device for segmenting and avoiding knots in bamboo. Background Art

[0002] In recent years, the implementation of forest resource protection projects has led to a year-on-year decrease in wood production. At the same time, the rapid growth of the domestic economy has led to a booming furniture and catering industries, which has increased demand for wood resources, leading to an increasingly acute contradiction between wood supply and demand. Bamboo has become an ideal substitute for wood due to its fast growth rate, short growth cycle, high strength-to-weight ratio, and easy processing, effectively alleviating the relationship between wood supply and demand.

[0003] The primary processing of bamboo includes multiple links such as fixed-length sawing, sorting, bamboo splitting, slicing, rough planing, drying, and fine planing. Although the equipment for bamboo splitting, slicing, rough planing, and fine planing is relatively mature, the sawing link is still highly dependent on manual operation. Manual sawing is not only labor-intensive and has a low safety factor, but the utilization rate of bamboo is also limited by the experience of the operator. Since 1970, after electric saws and oil saws replaced hand saws, the technological progress of bamboo sawing equipment has been relatively slow. In recent years, with the rapid development of automation and intelligent technology, the bamboo processing industry is facing a major opportunity to transform from traditional processing to large-scale, automated, and intelligent processing. In response to the technical bottlenecks in the bamboo sawing link, many scholars have actively carried out research to explore efficient and accurate automatic fixed-length sawing methods. Liang Ruilin developed a bamboo and wood processing fixed-length cutting equipment, but it was unable to identify bamboo joints and avoid them during the sawing process, which limited its application scope; Liu Yanhe et al. proposed an automatic bamboo length-fixing equipment that uses photoelectric sensors to detect bamboo length and bamboo joint avoidance. The average processing efficiency of the equipment is about 10.16m / min, which can ensure that there are no bamboo joints within 50mm from the small end of the bamboo segment. Although certain results have been achieved, there is still room for improvement in processing efficiency and bamboo joint avoidance accuracy; Li Shengwei et al. proposed a bamboo intelligent joint avoidance fixed-length sawing equipment with bamboo joint detection devices composed of 3 infrared detectors with camera and distance measurement functions, stepper motors and guide rails. The average processing efficiency of the equipment is about 27.37m / min, which can ensure that there are no bamboo joints within 30mm at both ends of the bamboo segment, and there are significant improvements in processing efficiency and bamboo joint avoidance accuracy.

[0004] However, the currently used infrared detectors still have limitations in bamboo joint detection. When encountering rainy weather, the bamboo will become smooth due to the scouring of rainwater. Since the infrared detector is very sensitive to the surface reflectivity of the detected object, the smooth surface of the bamboo will affect its detection results. Therefore, this paper proposes a bamboo fixed-length knot-avoiding sawing method, which uses visual detection to identify bamboo joints, aiming to overcome the limitations of infrared detectors, improve the automation and intelligence level of bamboo sawing, and provide technical support for the sustainable development of the bamboo primary processing industry. Summary of the invention

[0005] In view of this, the present application proposes a method for sawing bamboo in sections and avoiding knots to solve the problems reflected in the above-mentioned background technology.

[0006] The present application provides a bamboo segmentation and knot-avoiding sawing method, comprising:

[0007] Analyze the bamboo image of the bamboo to be sawed, and obtain the bamboo node position of the bamboo to be sawed;

[0008] Calculating whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is greater than a preset distance;

[0009] When the distance between the center line of the bamboo image and the position of the bamboo node on any side is less than a preset distance, performing node avoidance calculation to obtain a corresponding sawing position;

[0010] The bamboo material to be sawed is sawed at the sawing position, and the distances between the sawing position and the bamboo node positions on both sides are equal to or greater than the preset distances.

[0011] Optionally, the calculating whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is greater than a preset distance further includes:

[0012] The judgment is whether it is above the preset distance, the preset distance for the first sawing is that the distance between the subsequent cutting position and the left and right bamboo positions is set to A1 and A2, and the distance between the center line and the left and right bamboo positions is set to a1 and a2;

[0013] If a1 and a2 are both greater than A1 and A2, the centerline is outside the left and right preset distances, and no node avoidance calculation is required;

[0014] If a1 is less than or equal to A1 or a2 is less than or equal to A2, the center line is within the left and right avoidance distances or on the left and right bamboo nodes, and avoidance calculations are required.

[0015] Optionally, the first sawing includes:

[0016] In the first sawing, the bamboo cutting length X is determined according to the distance between industrial camera A and industrial camera B, and whether it is necessary to avoid the knots is confirmed and the avoidance calculation is performed. Since industrial camera A does not match the actual sawing position, the bamboo needs to be moved right to the actual sawing position for sawing. This offset distance is set to Y.

[0017] Optionally, the center line is within the left and right avoidance distances or is on the left and right bamboo nodes, and avoidance calculation is required, further comprising:

[0018] If the center line is on a bamboo node on either side, the avoidance distance Z must be equal to the sum of the offset distance Y and the distance a2 from the center line to the bamboo node on the right side;

[0019] If the center line is within the preset distance on the right, the avoidance distance Z must be equal to the difference between the preset distance on the right A2 and the distance a2 between the center line and the bamboo node on the right, and the sum of the difference and the offset distance Y;

[0020] If the center line is within the preset distance on the left, the avoidance distance Z needs to be equal to the sum of the preset distance A2 on the right, the distance a1 from the center line to the bamboo node on the left, and the offset distance Y.

[0021] Optionally, the calculating whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is greater than a preset distance includes:

[0022] The judgment is whether it is above the preset distance, and the preset distance of subsequent sawing is that the distance between the subsequent cutting position and the left and right bamboo positions is set to B1 and B2, and the distance between the center line and the left and right bamboo positions is set to b1 and b2;

[0023] If b1 and b2 are both greater than B1 and B2, the centerline is outside the left and right preset distances, and no node avoidance calculation is required;

[0024] If b1 is less than or equal to B1 or b2 is less than or equal to B2, the center line is within the left and right avoidance distances or on the left and right bamboo nodes, and avoidance calculations are required.

[0025] Optionally, the subsequent sawing further includes:

[0026] For the subsequent sawing, after completing the first sawing, the industrial camera B moves to the right by an offset distance Y, so that the distance between the industrial camera B and the saw blade at the sawing position matches the bamboo cutting length X. At this time, the industrial camera A stops working, and the industrial camera B collects data and performs knot avoidance calculations.

[0027] Optionally, the center line is within the left and right avoidance distances or on the left and right bamboo nodes, and avoidance calculations need to be performed, including:

[0028] If the center line is on a bamboo node on either side, the avoidance distance Z must be equal to the sum of the offset distance Y and the distance b2 from the center line to the bamboo node on the right side;

[0029] If the center line is within the preset distance on the right, the avoidance distance Z must be equal to the difference between the preset distance on the right B2 and the distance b2 between the center line and the bamboo joint on the right, and the sum of the difference and the offset distance Y;

[0030] If the center line is within the preset distance on the left, the avoidance distance Z needs to be equal to the sum of the preset distance B2 on the right, the distance b1 from the center line to the bamboo node on the left, and the offset distance Y.

[0031] Optionally, the present application also provides a bamboo segmentation and knot avoidance sawing hardware structure, comprising a mechanical module and a motion control module, and the hardware structure is started using the method described in any one of claims 1-7.

[0032] Optionally, it also includes an information processing module for running the YOLOv5 detection algorithm to detect the position information of the bamboo joints in the captured image in real time, and then pass the position information to the joint avoidance algorithm to calculate the joint avoidance distance.

[0033] The present application also provides an electronic device, including:

[0034] Industrial control computers: used for computing and control tasks in industrial environments, generally equipped with a general-purpose operating system and capable of complex data analysis and processing;

[0035] PLC: Programmable Logic Controller, a programmable memory that stores instructions for performing logical operations, sequential control, timing, counting and arithmetic operations, and controls various types of mechanical equipment or production processes through digital or analog input and output.

[0036] Wherein, the industrial control computer and PLC are configured to implement the method startup described in any one of claims 1 to 7 when executing the executable instructions.

[0037] The beneficial effects of the present application are as follows: the automatic bamboo sawing machine using the bamboo fixed-length knot-avoiding sawing method meets the current primary processing production needs, can ensure that there are no bamboo knots within 25 mm at both ends of the bamboo segment, and the knot-avoiding success rate reaches 100%. At the same time, the average processing efficiency reaches 30.12 m / min, which is about 3.77 times that of manual labor, and the labor cost is reduced by more than 50%. The method proposed in the present application can effectively promote the development of the bamboo primary processing industry towards scale, automation, and intelligence. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required in the embodiments or the description of the prior art. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0039] Figure 1 A flowchart showing a specific bamboo segmentation and knot-avoiding sawing method disclosed in the present application is shown;

[0040] Figure 2 A mechanical module structure diagram of a specific automatic bamboo sawing machine disclosed in the present application is shown;

[0041] Figure 3 A specific working flow diagram of an automatic bamboo sawing machine disclosed in the present application is shown;

[0042] Figure 4 The picture captured by the industrial camera A disclosed in the present application is shown;

[0043] Figure 5 The picture captured by the industrial camera B disclosed in the present application is shown;

[0044] Figure 6 A schematic diagram of a specific fixed-length sawing principle disclosed in the present application is shown;

[0045] Figure 7 A specific bamboo node distribution diagram disclosed in the present application is shown;

[0046] Figure 8 A schematic diagram of a bamboo basket part of a specific industrial camera A disclosed in the present application is shown;

[0047] Fig. 9 A schematic diagram of a subsequent cutting position of a specific industrial camera B disclosed in the present application is shown;

[0048] Fig.10 A specific avoidance distance calculation flow chart disclosed in the present application is shown. DETAILED DESCRIPTION

[0049] Various exemplary embodiments, features and aspects of the present application will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0050] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0051] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0052] In addition, in order to better illustrate the present application, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present application can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present application.

[0053] The overall structure of the automatic bamboo sawing machine of the present application is composed of a mechanical module, an information processing module and a motion control module.

[0054] like Figure 2 As shown, the mechanical module structure includes: 1. a stopper, 2. a presser, 3. a fixed clamp, 4. a feed roller, 5. a saw, 6. an industrial camera A and 7. an industrial camera B. The stopper and the presser are used to control the tail movement range of the bamboo material with irregular bending in the pulling process to prevent accidental injury to workers and damage to the machine; the fixed clamp is used to fix the bamboo material to prevent the bamboo material from moving or rotating during the sawing process, resulting in sawing failure; the feed roller is driven by a servo motor to accurately control the feeding according to the avoidance distance information; the saw is driven by two motors, the asynchronous motor drives the saw blade to rotate, and the servo motor drives the saw blade to move up and down; the industrial camera A is used to capture the information of the first sawing position; the industrial camera B is driven by the servo motor to move on the slide rail to capture the information of the next sawing position.

[0055] The information processing module consists of two industrial cameras and an industrial control computer (hereinafter referred to as the industrial computer). As the information input part, the two industrial cameras have an automatic exposure function and can quickly adapt to different lighting conditions to capture high-quality images. As the core of information processing, the industrial computer can run the YOLOv5 detection algorithm at a higher FPS, detect the position information of the bamboo nodes in the captured image in real time, and then pass the position information into the node avoidance algorithm to calculate the node avoidance distance.

[0056] The main controller of the motion control module is a PLC (Programmable Logic Controller), which controls the motion of the mechanical module. Figure 3 As shown in the figure, when the bamboo is placed in the equipment, the information processing module sends a start-valid signal. After the operator presses the start button, the sawing machine, the limiter and the presser are started at the same time for the first sawing. After the two industrial cameras capture the picture, the information is transmitted to the industrial computer. After the knot avoidance distance is calculated, the feed roller is started, the bamboo is moved to the actual sawing position, the fixed clamp is started to fix the bamboo, and then sawing is carried out. After the sawing is completed, the fixed clamp is closed. In the subsequent sawing, industrial camera A is turned off, industrial camera B is started, and the captured picture is transmitted to the industrial computer. After the knot avoidance distance is calculated, the feed roller is started, the bamboo is moved to the sawing position, the fixed clamp is started, and sawing is carried out and this action is repeated. After the sawing is completed, the presser and the limiter are turned off, and the saw machine remains on, waiting for the next bamboo, until the bamboo sawing task is completed.

[0057] This application uses the YOLOv5 detection algorithm to identify the location of bamboo joints. In the YOLOv5-7.0 version, there are five network models: YOLOv5n, YOLOv5s, YOLOv5m, YOLOv5l and YOLOv5x. This application uses YOLOv5s, which has a better balance between recognition accuracy and network structure complexity. It consists of four modules: Input, Backbone, Neck and Head.

[0058] The Input module mainly performs Mosaic data enhancement, adaptive anchor box calculation and data preprocessing; the Backbone module is mainly responsible for extracting the features of the input image and generating the image feature map; the Neck module uses a combination of feature pyramid network and path aggregation network to perform multi-scale feature extraction on the same feature map, and fuses the shallow position features of the detection object with the deep semantic features; the Head module classifies and locates the feature information output by Neck, thereby outputting the classification probability, confidence, box and other information of the detection target.

[0059] Specifically, this application uses a self-made data set, taking 3268 pictures taken at the bamboo processing site in Huoshan, Anhui, and using labelimg (a graphic image annotation tool) to annotate the data set. There are two types of labels, namely, joint and bam. The data set is divided into a training set and a validation set in a 4:1 ratio, and a computer is used to train the model based on the data set. The trained model test results are shown in Figure 2. Figure 4 and Figure 5 As shown, Figure 4 and Figure 5Figure a is captured in normal weather, and Figure b is captured in rainy weather. It can be clearly observed from Figure b that even after rain, the smooth surface of the bamboo does not affect the bamboo joint detection results, overcoming the limitations of the infrared detector. The bamboo joint detection results are all around 90% with no false detection or missed detection, which can meet the requirements of joint avoidance calculation.

[0060] like Figure 1 As shown, the bamboo material segmentation and knot-avoiding sawing method of the embodiment of the present application comprises the following steps:

[0061] S100, the present application is to install two industrial cameras at the front and rear positions of the bamboo material to be sawed respectively, and use the two industrial cameras to analyze the bamboo material image of the bamboo material to be sawed to obtain the bamboo node position.

[0062] Specifically, Figure 6 As shown, during the sawing process, the industrial camera A cannot be installed directly above the saw machine because the up and down sawing action of the saw machine will block the image capture by the industrial camera A. Therefore, the industrial camera A is arranged on the left side of the saw machine.

[0063] During the first sawing, the length is fixed by adjusting the distance between industrial camera A and industrial camera B. Figure 6 Where X is the fixed length of the bamboo segment, and Y is the offset distance between the sawing position captured by industrial camera A and the actual sawing position. First, turn on industrial camera A and industrial camera B at the same time to capture images, record the bamboo node position data at this time, and perform node avoidance calculation to confirm whether node avoidance is required and the node avoidance distance. It should be noted that since the sawing position captured by industrial camera A for the first time does not match the actual one, the bamboo needs to be moved right to the actual sawing position through the feeding roller for sawing.

[0064] Also, for subsequent sawing, industrial camera B needs to be moved to the same distance as the bamboo by the sawing machine. By controlling the distance between industrial camera B and the saw blade at the sawing position to be the fixed length of the bamboo, industrial camera A stops working at this time, and industrial camera B uses the current collected data and the previous collected data as the data of the actual front and back sawing positions for knot avoidance calculation, so as to determine whether knot avoidance is needed and the knot avoidance distance, and then adjust the position of the bamboo and perform sawing.

[0065] S200, this application uses the YOLOv5 detection algorithm to identify the location of bamboo nodes in the images captured by two industrial cameras, and at the same time extracts the center line of the image to calculate whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is above the preset distance.

[0066] Specifically, Figure 7As shown, the left and right preset distances of the first cut of the bamboo basket are set to A1 and A2, the saw machine cannot cut within this range, and the distances from the center line of the captured image of industrial camera A to the left and right bamboo joints are set to a1 and a2. The left and right preset distances of the cutting position of industrial camera B are set to B1 and B2, and the distances from the center line of the captured image to the left and right bamboo joints are set to b1 and b2.

[0067] Among them, Figure 8 and Fig. 9 As shown in the figure, there are five situations of bamboo node distribution at the lower cutting position, including: ① the center line position is outside the range of A1 (B1) and A2 (B2), ② the center line is on the right bamboo node, ③ the center line is on the left bamboo node, ④ the center line is within the range of A2 (B2), and ⑤ the center line is within the range of A1 (B1). In the above situations, except for the situation where the center line position is outside the range of A1 (B1) and A2 (B2), the other situations need to calculate the avoidance distance.

[0068] S300, according to the positional relationship between the center line and the bamboo node, when the distance between the center line of the bamboo image and the position of the bamboo node on either side is judged to be less than a preset distance, a node avoidance method based on a dichotomy design is adopted to calculate the node avoidance distance and then perform precise sawing of the bamboo.

[0069] Specifically, Figure 8 For example, in situation ①, there is no need to move to avoid the knot; in situations ② and ③, the knot avoidance distance Z needs to be equal to the sum of the offset distance Y and the distance a2 from the center line to the right bamboo node; in situation ④, the knot avoidance distance Z needs to be equal to the difference between the right preset distance A2 and the distance a2 from the center line to the right bamboo node, the difference and the offset distance Y; in situation ⑤, the knot avoidance distance Z needs to be equal to the sum of the right preset distance A2, the distance a1 from the center line to the left bamboo node and the offset distance Y.

[0070] The node avoidance distance is set to Z, and the offset distance between the sawing position captured by the industrial camera A and the actual sawing position is set to Y. Considering the distribution of bamboo nodes at the left and right ends of the bamboo segment, the node avoidance distance is calculated. There are many situations and it is difficult to solve it using the exhaustive method. Therefore, this application uses the binary search iterative solution to solve the node avoidance distance Z by the offset distance Y of the industrial camera and the step length α.

[0071] The binary search method is to find a value x for an ordered list [a, b]. In order to speed up the search, first determine the size of the middle value c of the ordered list and x, select the area where x is located, and assume that x>c, then set a=c to obtain a new interval [a, b]; repeat the above steps until the position of the target x in the table is found or the position where there is no value x in the result ordered list is obtained.

[0072] Specifically, the binary search method is introduced into the solution of the node avoidance distance Z. By using the half-length of the bamboo node spacing at the bamboo basket as the starting step length α, first stepping into the suitable sawing conditions, then considering the bamboo material utilization rate to retreat to the restriction conditions, and finally enumerating the optimal value that meets the sawing conditions within a small range. Due to the limitation of the bamboo node width, the step length α is chosen to step in a step-by-step binary manner to prevent the situation where the bamboo material utilization rate is reduced due to excessively long steps. In the process of finding the solution, it appears that only one end meets the restriction conditions after the first step, and the detailed classification is too cumbersome. This application uses a fixed step length of 10 mm to re-find the solution to simplify the solution process.

[0073] like Fig.10 As shown, the node avoidance distance is set to Z, the bamboo node spacing at the bamboo basket is set to N, and the offset distance between the sawing position captured by the industrial camera A and the actual sawing position is set to Y.

[0074] S301, set Z to 0, N1 to half of N, Z1 is the sum of Z and N1, and determine whether the distance between Z1 and the two ends meets the sawing condition. If both ends meet the sawing condition, execute S311; if neither end meets the sawing condition, execute S321; if only one end meets the sawing condition, execute S331.

[0075] S311, set N2 to half of N1 and N2 must be greater than or equal to 10mm, set Z2 to the difference between Z1 and N2, and determine whether the distance between Z2 and the two ends meets the sawing condition. If both ends meet the sawing condition, assign Z2 to Z1, assign N2 to N1, and repeat S311; if only one end meets the sawing condition, execute S312.

[0076] S312, set Z3 to the sum of Z2 plus 10mm, and determine whether the distance between Z3 and the two ends meets the sawing condition. If the two ends do not meet the sawing condition, assign the current Z3 to Z2 and repeat S312; if both ends meet the sawing condition, the optimal avoidance distance Z3+Y has been found.

[0077] S321, set N2 to half of N1 and N2 must be greater than or equal to 10mm, set Z2 to the sum of Z1 and N2, and determine whether the distance between Z2 and the two ends meets the sawing condition. If both ends meet the sawing condition, execute S322; if either end does not meet the sawing condition, assign Z2 to Z1, assign N2 to N1, and repeat S321.

[0078] S322, set N3 to half of N2 and N3 must be greater than or equal to 10mm, set Z3 to the difference between Z2 and N3, and determine whether the distance between Z3 and the two ends meets the sawing condition. If the two ends do not meet the sawing condition and only one end meets the sawing condition, execute S323; if both ends meet the sawing condition, assign Z3 to Z2, assign N3 to N2, and repeat S322.

[0079] S323, set Z4 to the sum of Z3 plus 10 mm, and then obtain the optimal avoidance distance Z4+Y.

[0080] S331, set Z1 to the sum of Z plus 10mm, and determine whether the distance between Z1 and the two ends meets the sawing condition. If both ends meet the sawing condition, execute S332; if either end does not meet the sawing condition, assign the current Z1 to Z, and repeat S331.

[0081] S332, set Z2 to the difference of Z1 minus 10mm, and judge whether the distance between Z2 and the two ends meets the sawing condition. If the two ends do not meet the sawing condition, execute S333; if both ends meet the sawing condition, assign the current Z2 to Z1, and repeat S332.

[0082] S333, set Z3 to the sum of Z2 plus 10mm, and then obtain the optimal avoidance distance Z3+Y.

[0083] S400, the present application saws bamboo at a sawing position and the distances between the sawing position and the bamboo nodes on both sides are equal to or greater than a preset distance.

[0084] Specifically, Figure 8 and Fig. 9 As shown in case ①, in this case, since the center line of the bamboo image is outside the preset distance on both sides, there is no need to perform knot avoidance calculation, the knot avoidance distance Z is equal to the offset distance Y, and the bamboo can be sawed directly at this sawing position.

[0085] The specific implementation process of this application is as follows:

[0086] During the sawing process, the sawing action will block the camera A from capturing the image, so it is impossible to install the camera A directly above the saw. Therefore, this article chooses to place the camera A on the left side of the saw. When sawing for the first time, the distance between the camera A and the camera B is adjusted to a fixed length, such as Figure 6 shown. Figure 6Where X is the fixed length of the bamboo segment, and Y is the distance between the sawing position captured by industrial camera A and the actual sawing position. First, turn on industrial camera A and industrial camera B at the same time to capture images, record the bamboo node position data at this time, and perform node avoidance calculation to confirm whether node avoidance is required and the node avoidance distance. It should be noted that since the sawing position captured by industrial camera A for the first time does not match the actual one, the bamboo needs to be moved right to the actual sawing position through the feeding roller for sawing. Subsequent sawing requires that industrial camera B also move the same distance to the sawing machine as the bamboo moves. By controlling the distance between industrial camera B and the saw blade to the fixed length of the bamboo, industrial camera A stops working at this time, and industrial camera B uses the data collected this time and the data collected last time as the data of the actual front and rear sawing positions for node avoidance calculation, thereby determining whether node avoidance is required and the node avoidance distance, and then adjusts the position of the bamboo and performs sawing.

[0087] In the actual production process, due to the difference in subsequent processed products, the distance requirements for avoiding the knots are also different. The processing method in this article is as follows: the left and right limit distances of the first cut of the bamboo basket are set to A1 and A2, and the saw machine cannot cut within this range. The distance from the center line of the captured image of industrial camera A to the left and right bamboo knots is set to a1 and a2. The left and right limit distances of the cutting position of industrial camera B are set to B1 and B2, and the distance from the center line of the captured image to the left and right bamboo knots is set to b1 and b2.

[0088] According to the above requirements, there are five types of bamboo node distribution at the cutting point, such as Figure 7 As shown:

[0089] ①The centerline is outside the range of A1(B1) and A2(B2);

[0090] ②The center line is located on the right bamboo node;

[0091] ③The center line is located on the left bamboo node;

[0092] ④The center line is within the range of A2(B2);

[0093] ⑤The center line is within the range of A1(B1).

[0094] According to the above five types of bamboo node distribution, Table 1 explains how to calculate the node avoidance distance at the bamboo basket. In Table 1, Z is the node avoidance distance, and Y is the offset distance between the sawing position captured by the industrial camera A and the actual sawing position.

[0095] Tab.1 Calculation of nodes avoidance distance ofbamboo basket

[0096]

[0097] When considering the distribution of bamboo nodes at both ends of the bamboo segment, the node avoidance distance calculation is complicated and difficult to solve using the exhaustive method. In this case, the binary iteration method (Ma Zhanchuan, 2024) will be a better choice. The node avoidance distance Z is solved by the offset distance Y and step length α of the industrial camera.

[0098] The basic idea of ​​the binary search method (Wang Haitao et al., 2006): For an ordered list [a, b], to find a value x, in order to speed up the search, first determine the size of the middle value c of the ordered list and x, select the area where x is located, and assume that x>c, then let a=c and get a new interval [a, b]; repeat the above steps until the position of the target x in the table is found or the position where there is no value x in the resulting ordered list is obtained.

[0099] This paper introduces the above idea into the solution of the avoidance distance Z. By using the half-length of the bamboo node spacing at the bamboo basket as the starting step length α, we first step into the conditions suitable for sawing, then consider the bamboo utilization rate to retreat to the restriction conditions, and finally enumerate the optimal value that meets the sawing conditions in a small range. Due to the limitation of bamboo node width, the step length α is chosen to step in a step-by-step binary manner to prevent the situation where the bamboo utilization rate is reduced due to excessive steps. In the solution process, after the first step, only one end meets the restriction conditions, and the detailed classification is too cumbersome. This paper chooses to re-solve with a fixed step length of 10mm to simplify the solution process. Specific solution steps, such as Fig.10 shown.

[0100] The beneficial effect of the present application is that the automatic bamboo sawing machine using the bamboo fixed-length knot-avoiding sawing method meets the current primary processing production needs, can ensure that there are no bamboo knots within 25 mm at both ends of the bamboo segment, and the knot-avoiding success rate reaches 100%. At the same time, the average processing efficiency reaches 30.12 m / min, which is about 3.77 times that of manual labor, and the labor cost is reduced by more than 50%. The method proposed in the present application can effectively promote the development of the bamboo primary processing industry towards scale, automation, and intelligence.

[0101] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A bamboo segmentation and knot-avoiding sawing method, characterized in that: include: Analyze the bamboo image of the bamboo to be sawed, and obtain the bamboo node position of the bamboo to be sawed; Calculating whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is greater than a preset distance; When the distance between the center line of the bamboo image and the position of the bamboo node on any side is less than a preset distance, performing node avoidance calculation to obtain a corresponding sawing position; The bamboo material to be sawed is sawed at the sawing position, and the distances between the sawing position and the bamboo node positions on both sides are equal to or greater than the preset distances.

2. The bamboo segmentation and knot-avoiding sawing method according to claim 1, characterized in that: The calculating whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is greater than a preset distance includes: The judgment is whether it is above the preset distance, the preset distance for the first sawing is that the distance between the subsequent cutting position and the left and right bamboo positions is set to A1 and A2, and the distance between the center line and the left and right bamboo positions is set to a1 and a2; If a1 and a2 are both greater than A1 and A2, the centerline is outside the left and right preset distances, and no node avoidance calculation is required; If a1 is less than or equal to A1 or a2 is less than or equal to A2, the center line is within the left and right avoidance distances or on the left and right bamboo nodes, and avoidance calculations are required.

3. The bamboo segmentation and knot-avoiding sawing method according to claim 2, characterized in that: The first sawing comprises: In the first sawing, the bamboo cutting length X is determined according to the distance between industrial camera A and industrial camera B, and whether it is necessary to avoid the knots is confirmed and the avoidance calculation is performed. Since industrial camera A does not match the actual sawing position, the bamboo needs to be moved right to the actual sawing position for sawing. This offset distance is set to Y.

4. The bamboo segmentation and knot-avoiding sawing method according to claim 2, characterized in that: If the center line is within the left and right avoidance distances or on the left and right bamboo nodes, avoidance calculations need to be performed, including: If the center line is on a bamboo node on either side, the avoidance distance Z must be equal to the sum of the offset distance Y and the distance a2 from the center line to the bamboo node on the right side; If the center line is within the preset distance on the right, the avoidance distance Z must be equal to the difference between the preset distance on the right A2 and the distance a2 between the center line and the bamboo node on the right, and the sum of the difference and the offset distance Y; If the center line is within the preset distance on the left, the avoidance distance Z needs to be equal to the sum of the preset distance A2 on the right, the distance a1 from the center line to the bamboo node on the left, and the offset distance Y.

5. The bamboo segmentation and knot-avoiding sawing method according to claim 1, characterized in that: The calculating whether the distance between the center line of the bamboo image and the positions of the bamboo nodes on both sides is greater than a preset distance includes: The judgment is whether it is above the preset distance, and the preset distance of subsequent sawing is that the distance between the subsequent cutting position and the left and right bamboo positions is set to B1 and B2, and the distance between the center line and the left and right bamboo positions is set to b1 and b2; If b1 and b2 are both greater than B1 and B2, the centerline is outside the left and right preset distances, and no node avoidance calculation is required; If b1 is less than or equal to B1 or b2 is less than or equal to B2, the center line is within the left and right avoidance distances or on the left and right bamboo nodes, and avoidance calculations are required.

6. The bamboo segmentation and knot-avoiding sawing method according to claim 5, characterized in that: The subsequent sawing comprises: For the subsequent sawing, after completing the first sawing, the industrial camera B moves to the right by an offset distance Y, so that the distance between the industrial camera B and the saw blade at the sawing position matches the bamboo cutting length X. At this time, the industrial camera A stops working, and the industrial camera B collects data and performs knot avoidance calculations.

7. The bamboo segmentation and knot-avoiding sawing method according to claim 5, characterized in that: If the center line is within the left and right avoidance distances or on the left and right bamboo nodes, avoidance calculations need to be performed, including: If the center line is on a bamboo node on either side, the avoidance distance Z must be equal to the sum of the offset distance Y and the distance b2 from the center line to the bamboo node on the right side; If the center line is within the preset distance on the right, the avoidance distance Z must be equal to the difference between the preset distance on the right B2 and the distance b2 between the center line and the bamboo joint on the right, and the sum of the difference and the offset distance Y; If the center line is within the preset distance on the left, the avoidance distance Z needs to be equal to the sum of the preset distance B2 on the right, the distance b1 from the center line to the bamboo node on the left, and the offset distance Y.

8. A bamboo segmentation and knot-avoiding sawing hardware structure, characterized in that: Comprising a mechanical module and a motion control module, the hardware structure is started using the method described in any one of claims 1-7.

9. The bamboo segmentation and knot avoidance sawing hardware structure according to claim 8 is characterized in that: It also includes an information processing module for running the YOLOv5 detection algorithm, detecting and capturing the position information of bamboo joints in the picture in real time, and then passing the position information into the joint avoidance algorithm to calculate the joint avoidance distance.

10. An electronic device, characterized in that: include: Industrial control computers: used for computing and control tasks in industrial environments, generally equipped with a general-purpose operating system and capable of complex data analysis and processing; PLC: Programmable Logic Controller, a programmable memory that stores instructions for performing logical operations, sequential control, timing, counting and arithmetic operations, and controls various types of mechanical equipment or production processes through digital or analog input and output. Wherein, the industrial control computer and PLC are configured to implement the method startup described in any one of claims 1 to 7 when executing the executable instructions.

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