A verification and rejection device and method under high-speed conditions

Abstract

The present invention relates to the field of intelligent manufacturing technology, and particularly relates to a verification and rejection device and a verification and rejection method under high-speed conditions. The device includes: a conveyor belt, a code-reading trigger photoelectric sensor, a depth camera, a code reader, a rejection component, a rejection detection photoelectric sensor, an encoder, and a PLC. The precise position of the bottle cap is obtained through the depth camera, and the code reader is controlled to be aligned with the bottle cap to ensure the accuracy of QR code reading. By introducing a vibration sensor and a light sensor, which are used to detect changes in environmental vibration and light intensity, and dynamically adjusting the sensitivity of the photoelectric sensor and the trigger delay of the rejection device through the PLC, high-precision QR code verification and precise rejection of unqualified products under high-speed conditions are achieved, significantly improving production efficiency and product quality.

Description

Technical Field

[0001] The present invention relates to the field of intelligent manufacturing technology, and particularly relates to a verification and rejection device and a verification and rejection method under high-speed conditions. Background Art

[0002] With the rapid development of industrial automation, high-speed production lines have been widely used in the packaging, food, and beverage industries. On these production lines, product quality verification and rejection of defective products are key links to ensure the product qualification rate. Existing verification and rejection systems usually rely on photoelectric sensors and PLC control, use trigger signals to verify identification information such as two-dimensional codes, and remove defective products from the conveyor belt through a rejection device.

[0003] Currently, the accuracy of two-dimensional code verification and the success rate of rejection are affected by various factors under high-speed conditions, such as the vibration of the conveyor belt, changes in ambient light, and delays in sensor signals. In addition, existing systems usually have difficulty in real-time adjusting the sensitivity of photoelectric sensors or the trigger logic of the rejection device to adapt to complex environmental changes. This lack of intelligent dynamic adjustment ability may lead to incorrect reading of two-dimensional codes or rejection failures, thereby affecting production efficiency and product quality. Summary of the Invention

[0004] The problems to be solved by the present invention are the problems of missed rejection, instability, and poor environmental adaptability when dealing with defective products on high-speed production lines. The purpose is to provide a verification and rejection device and a verification and rejection method under high-speed conditions, which realize the functions of two-dimensional code verification and precise rejection of defective products for caps conveyed at high speed under complex environmental conditions. At the same time, by dynamically adjusting the sensitivity of photoelectric sensors and the trigger delay of the rejection device, the adaptability, accuracy, and reliability of the verification and rejection system are improved.

[0005] The present invention is achieved by the following technical solutions:

[0006] A verification and rejection device under high-speed conditions, comprising: a conveyor belt, a code-reading trigger photoelectric sensor, a depth camera, a code reader, a rejection component, a rejection detection photoelectric sensor, an encoder, and a PLC;

[0007] The code-reading trigger photoelectric sensor, the code reader, the rejection component, and the rejection detection photoelectric sensor are arranged in sequence along the conveying direction of the conveyor belt, and the conveyor belt is used for conveying caps with two-dimensional codes;

[0008] Both the code-reading trigger photoelectric sensor and the rejection detection photoelectric sensor are arranged on one side of the conveyor belt, and the detection direction is perpendicular to the conveying direction of the caps; the depth camera and the code reader are arranged in parallel and are located above the two-dimensional code reading area of the caps;

[0009] The rejection component applies a lateral force to the bottle caps located on the conveyor belt;

[0010] The conveyor belt, the code-reading trigger photoelectric sensor, the depth camera, the code reader, the rejection component, the rejection detection photoelectric sensor, and the encoder are all electrically connected to the PLC.

[0011] Furthermore, the device further includes a vibration sensor and a light sensor. The vibration sensor is arranged on the conveyor belt, the light sensor is arranged near the code-reading trigger photoelectric sensor and the rejection detection photoelectric sensor, and both the vibration sensor and the light sensor are electrically connected to the PLC.

[0012] A verification and rejection method under high-speed conditions, based on a verification and rejection device under high-speed conditions as described above, the verification and rejection method includes:

[0013] The code-reading trigger photoelectric sensor generates a trigger signal when detecting that the bottle cap passes through the trigger point;

[0014] According to the trigger signal, the PLC triggers the code reader to read the data of the two-dimensional code on the bottle cap;

[0015] The PLC receives the reading result of the code reader and compares it with the pre-stored data to generate a corresponding verification signal;

[0016] According to the verification signal, it is judged whether the bottle cap is a qualified product. If it is a qualified product, no rejection process is performed; if it is an unqualified product, a control signal is applied to the rejection component;

[0017] The rejection component applies a lateral force to the unqualified product to remove the bottle cap from the conveyor belt;

[0018] The rejection detection photoelectric sensor verifies the rejection result and issues an alarm signal or stops the conveyor belt when the unqualified product is not successfully rejected.

[0019] Specifically, the method for triggering the code reader to read the data of the two-dimensional code on the bottle cap includes:

[0020] The method for the code reader to read the data of the two-dimensional code on the bottle cap includes:

[0021] Determine the distance from the code-reading trigger photoelectric sensor to the code-reading area , and convert it into a pulse value , where is the pulse resolution of the encoder;

[0022] After the PLC receives the trigger signal, it records the current count value of the encoder and uses it as the code-reading reference value ;

[0023] Calculate the difference between the current encoder count value and the target position , , where is the count value feedback by the encoder in real time;

[0024] Calculate the dynamic compensation error parameter , , where is the running speed of the conveyor belt, is the signal delay time of the PLC, is the correction of the environmental error to the pulse value, and are the empirical weight coefficients;

[0025] If , the PLC sends a code reading control signal to the code reader.

[0026] Specifically, obtain the accurate position of the bottle cap through the depth camera and control the code reader to align with the bottle cap. The method includes:

[0027] The depth camera collects the initial depth map of the code reading area ;

[0028] Perform mean filtering denoising on the depth values in the depth map to obtain the depth map ;

[0029] Set the dynamic depth threshold and , , where is the median of the depth values of the depth map, is the interquartile range of the depth values of the depth map, is the dynamic adjustment coefficient;

[0030] Perform binary segmentation on the depth map to obtain the mask map , , where is the depth map the depth value of the pixel coordinate in, is the mask map the binary depth value of the pixel coordinate in;

[0031] Determine the centroid of the bottle cap in the pixel coordinates , , where is the area of the bottle cap in the pixel coordinates ;

[0032] Obtain the two-dimensional physical coordinates of the bottle cap , ;

[0033] Obtain the actual center position of the barcode reader , and calculate the error value between the cap position and the actual center position , if then perform QR code reading; otherwise, adjust the actual center position of the barcode reader until is satisfied, where and are the allowable horizontal error range and vertical error range.

[0034] Optionally, the allowable horizontal error range , the allowable vertical error range , where and are the static basic error ranges, is the conveyor belt speed, is the depth camera frame rate, is the speed influence coefficient;

[0035] The method for adjusting the actual center position of the barcode reader is: , where is the adjusted actual center position of the barcode reader, is the adjustment step coefficient.

[0036] Specifically, detect the vibration intensity of the conveyor belt through a vibration sensor, detect the light intensity near the barcode reading photoelectric sensor and the rejection detection photoelectric sensor through a light sensor, and trigger the adjustment of the sensitivity of the photoelectric sensor and the trigger delay of the rejection device when the vibration intensity or light change exceeds a preset threshold.

[0037] Optionally, the adjustment method includes:

[0038] Collect environmental signals and record them in the form of a time series , where is the vibration intensity at time is the light intensity at time;

[0039] Determine the quantization index of the vibration intensity , where is the sampling time window;

[0040] Calculate the relative change rate of the light intensity , where and are the maximum and minimum light intensities within the past time window , is the average light intensity; ​

[0041] Determine the dynamic adjustment function of the photoelectric sensor sensitivity , where is the initial sensitivity of the photoelectric sensor, is the influence coefficient used to control the effects of vibration and light changes on the sensitivity;

[0042] Determine the dynamic adjustment function of the trigger delay of the rejection device , where is the initial trigger delay of the rejection device, is the influence coefficient used to control the effects of vibration and light changes on the trigger delay. Build a dynamic prediction model based on the long short-term memory network, and use and 's historical values as inputs to obtain the prediction result ;

[0043] Adjust the sensitivity and trigger delay in advance according to the prediction result; .

[0044] Specifically, the method for verifying the rejection result by the rejection detection photoelectric sensor includes:

[0045] Determine the distance from the rejection area to the rejection detection photoelectric sensor , and convert it into a pulse value , where is the pulse resolution of the encoder;

[0046] The PLC records the encoder count value when the rejection action occurs , and calculates the target count value of the rejection detection position ;

[0047] Obtain When, the feedback signal of the rejection detection photoelectric sensor. If no trigger signal is detected, it is determined that the rejection is successful; if a trigger signal is detected, it is determined that the rejection fails.

[0048] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0049] The device in the present invention includes a conveyor belt, a code reading trigger photoelectric sensor, a depth camera, a code reader, a rejection component, a rejection detection photoelectric sensor, an encoder, and a PLC, and combines multiple sensing devices to realize the two-dimensional code verification and rejection of high-speed conveyed bottle caps.

[0050] The present invention obtains the precise position of the bottle cap through a depth camera and controls the code reader to align with the bottle cap to ensure the accuracy of QR code reading. By introducing a vibration sensor and a light sensor to detect changes in ambient vibration and light intensity, and dynamically adjusting the sensitivity of the photoelectric sensor and the trigger delay of the rejection device through a PLC, high-precision QR code verification and precise rejection of unqualified products under high-speed conditions are achieved, significantly improving production efficiency and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings illustrate exemplary embodiments of the present invention and, together with the description thereof, are used to explain the principles of the present invention. These drawings are included to provide a further understanding of the present invention, and the drawings are included in this specification and form a part of this specification, and do not constitute a limitation on the embodiments of the present invention.

[0052] Figure 1 is a schematic structural diagram of a verification and rejection device under high-speed conditions according to the present invention.

[0053] Figure 2 is a schematic flow diagram of a verification and rejection method under high-speed conditions according to the present invention.

[0054] Reference numerals: 1 - conveyor belt, 2 - code reading trigger photoelectric sensor, 3 - code reader, 4 - rejection component, 5 - rejection detection photoelectric sensor, 6 - encoder. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0055] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the relevant content and do not limit the present invention.

[0056] In addition, it should be noted that only parts related to the present invention are shown in the drawings for the convenience of description.

[0057] Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and embodiments.

[0058] Embodiment 1

[0059] As Figure 1 shown, a verification and rejection device under high-speed conditions includes: a conveyor belt 1, a code reading trigger photoelectric sensor 2, a depth camera, a code reader 3, a rejection component 4, a rejection detection photoelectric sensor 5, an encoder 6, and a PLC;

[0060] The code-reading trigger photoelectric sensor 2, the code reader 3, the rejection component 4, and the rejection detection photoelectric sensor 5 are arranged in sequence along the conveying direction of the conveyor belt 1. The conveyor belt 1 is used to convey the bottle caps with two-dimensional codes; the bottle caps with two-dimensional codes are sequentially conveyed to each functional area, including the two-dimensional code reading area, the rejection area, and the rejection detection area.

[0061] Both the code-reading trigger photoelectric sensor 2 and the rejection detection photoelectric sensor 5 are arranged on one side of the conveyor belt 1, and the detection direction is perpendicular to the conveying direction of the bottle cap; the depth camera and the code reader 3 are arranged in parallel and are located above the two-dimensional code reading area of the bottle cap;

[0062] The rejection component 4 exerts a lateral force on the bottle cap located on the conveyor belt 1 to reject it from the conveyor belt 1.

[0063] The conveyor belt 1, the code-reading trigger photoelectric sensor 2, the depth camera, the code reader 3, the rejection component 4, the rejection detection photoelectric sensor 5, and the encoder 6 are all electrically connected to the PLC.

[0064] The code-reading trigger photoelectric sensor 2 is installed on one side of the conveyor belt 1 to vertically detect the passing of the bottle cap. When the bottle cap reaches the two-dimensional code reading area, this photoelectric sensor generates a trigger signal to notify the code reader 3 to read the two-dimensional code. The depth camera is used to obtain the three-dimensional position of the bottle cap in real time, assist the code reader 3 to align the position of the bottle cap, and improve the accuracy of two-dimensional code reading. The code reader 3 is used to read the two-dimensional code information on the bottle cap and send the data to the PLC for comparison and verification.

[0065] The rejection detection photoelectric sensor 5 is arranged behind the rejection component 4 and is used to detect whether there is still a bottle cap in the rejection area: if no signal is detected, it indicates that the rejection is successful. If a signal is detected, it indicates that the rejection fails, and the PLC will issue an alarm signal or stop the conveyor belt 1 from running.

[0066] The encoder 6 is installed on the conveyor belt 1 to record the movement position of the conveyor belt 1 in real time, generate a pulse signal, and supply it to the PLC to calculate the precise timing of triggering and rejection.

[0067] The PLC, as the core control system, is connected to all sensors, cameras, the code reader 3, and the rejection component 4 to coordinate the entire verification and rejection process.

[0068] The device further includes a vibration sensor and a light sensor. The vibration sensor is arranged on the conveyor belt 1 and is used to detect the running vibration condition of the conveyor belt 1. The light sensor is arranged near the code-reading trigger photoelectric sensor 2 and the rejection detection photoelectric sensor 5 and is used to monitor the change of the ambient light intensity. Both the vibration sensor and the light sensor are electrically connected to the PLC.

[0069] The working process is briefly described as follows:

[0070] The bottle cap is conveyed to the detection range of the code-reading trigger photoelectric sensor 2 through the conveyor belt 1. After the trigger signal is generated, the depth camera and the code reader 3 are linked to complete the QR code reading.

[0071] The PLC compares the QR code information of the code reader 3 with the pre-stored data to determine whether the bottle cap is a defective product.

[0072] For defective bottle caps, the PLC controls the rejection component 4 to apply a lateral force to remove the bottle cap from the conveyor belt 1.

[0073] The rejection detection photoelectric sensor 5 verifies the rejection result. If the rejection fails (the bottle cap signal is detected), the PLC triggers an alarm or stops the conveyor belt 1 from running.

[0074] The vibration sensor and the light sensor detect the vibration and light intensity of the conveyor belt 1 in real time. The PLC adjusts the sensitivity of the photoelectric sensor and the trigger delay of the rejection device according to the detection results to ensure the stable operation of the equipment.

[0075] Embodiment 2

[0076] As Figure 2 shown, a verification and rejection method under high-speed conditions is provided. Based on the above verification and rejection device under high-speed conditions, the verification and rejection method includes:

[0077] The code-reading trigger photoelectric sensor detects that a trigger signal is generated when the bottle cap passes through the trigger point; this signal is received by the PLC and used as the trigger condition for the subsequent control logic.

[0078] According to the trigger signal, the PLC triggers the code reader to read the data of the QR code on the bottle cap; the QR code information on the bottle cap is read, and the reading result is transmitted back to the PLC.

[0079] The PLC receives the reading result of the code reader and compares it with the pre-stored data (qualified information) to generate a corresponding verification signal;

[0080] According to the verification signal, it is judged whether the bottle cap is a qualified product. If it is a qualified product, no rejection process is carried out; if it is a defective product, a control signal is applied to the rejection component;

[0081] The rejection component applies a lateral force to the defective product to remove the bottle cap from the conveyor belt;

[0082] The rejection detection photoelectric sensor verifies the rejection result and issues an alarm signal or stops the conveyor belt from running when the defective product is not successfully rejected. If the bottle cap signal cannot be detected, it indicates that the rejection is successful; if the bottle cap signal is still detected, it is determined that the rejection fails.

[0083] Embodiment 3

[0084] Generate a trigger signal by reading the code and triggering the photoelectric sensor. Combine the position information fed back by the encoder and the dynamic compensation error parameter to accurately determine the timing when the bottle cap reaches the QR code reading area, and control the PLC to send a signal to the code reader to ensure the accuracy and timeliness of QR code reading. The method for triggering the code reader to read the data of the QR code on the bottle cap includes:

[0085] Determine the distance from the code-reading trigger photoelectric sensor to the reading area and convert the distance into a pulse value where is the pulse resolution of the encoder;

[0086] When the code-reading trigger photoelectric sensor detects that the bottle cap passes the trigger point, after the PLC receives the trigger signal, record the current count value of the encoder and use it as the code-reading reference value i.e., it represents the position when the bottle cap passes the trigger point and is used to calculate the target position.

[0087] The target position is the count value of the reading area, and the calculation method is : Calculate the difference between the current encoder count value and the target position , where is the count value fed back by the encoder in real time;

[0088] To adapt to the influence of conveyor belt speed fluctuation, signal delay and environmental interference in the high-speed production environment, calculate the dynamic compensation error parameter , where is the running speed of the conveyor belt, is the signal delay time of the PLC, is the correction of the pulse value due to environmental error (such as errors caused by vibration, temperature change, etc.), and are empirical weight coefficients used to adjust the contribution of speed and delay to the error.

[0089] Judge whether it is within the range of the dynamic compensation error parameter . If , the PLC sends a code-reading control signal to the code reader.

[0090] Example 4

[0091] In this example, a depth camera is used to obtain the accurate position of the bottle cap. By calculating the two-dimensional physical coordinates of the bottle cap and comparing and adjusting them with the actual center position of the code reader, the code reader is ensured to be aligned with the bottle cap to achieve accurate reading of the QR code. The method includes key steps such as depth camera calibration, depth map processing, coordinate calculation and error adjustment. The specific method includes:

[0092] Calibrate the internal parameters of the depth camera using a calibration board to obtain the camera internal parameter matrix , , where is the focal length of the depth camera, in pixels is the principal offset of the depth camera, used to correct the offset between the optical axis and the image center

[0093] The depth camera acquires the initial depth map of the code reading area .

[0094] Perform mean filtering denoising on the depth values in the depth map to obtain the depth map , where is the pixel coordinate of the neighborhood window

[0095] Based on the median and interquartile range of the denoised depth map, calculate the dynamic depth threshold and , , where is the median of the depth values of the depth map is the interquartile range of the depth values of the depth map is the dynamic adjustment coefficient

[0096] Perform binary segmentation on the depth map to obtain the mask map , , where is the depth map in the pixel coordinate depth value is the mask map in the pixel coordinate binary depth value

[0097] Determine the centroid of the bottle cap in pixel coordinates

[0098] Determine the centroid of the bottle cap in pixel coordinates , , where is the area of the bottle cap in pixel coordinates ;

[0099] Obtain the two-dimensional physical coordinates of the bottle cap , ;

[0100] Obtain the actual center position of the barcode reader , and calculate the error value between the bottle cap position and the actual center position . If then perform QR code reading; otherwise, adjust the actual center position of the barcode reader until , where and are the allowable horizontal error range and vertical error range.

[0101] Allowable horizontal error range , allowable vertical error range , where and are the static base error range, is the conveyor belt speed, is the depth camera frame rate, is the speed influence coefficient; as the conveyor belt speed increases, the horizontal error range increases accordingly to adapt to the dynamic offset of the bottle cap during high-speed operation, thereby improving the alignment tolerance of the barcode reader to the bottle cap.

[0102] When the error between the position of the bottle cap and the position of the barcode reader exceeds the allowable range, the actual center position of the barcode reader needs to be adjusted. The method for adjusting the actual center position of the barcode reader is: , where is the adjusted actual center position of the barcode reader, is the adjustment step coefficient, which is used to control the amplitude of each adjustment to ensure a stable and accurate adjustment process.

[0103] By adjusting the position of the barcode reader, the alignment error caused by the dynamic offset of the bottle cap is compensated to ensure that the barcode reader can accurately cover the QR code area on the bottle cap.

[0104] Example Five

[0105] Detect the vibration intensity of the conveyor belt through a vibration sensor, detect the light intensity near the barcode reading photoelectric sensor and the rejection detection photoelectric sensor through a light sensor, and trigger the adjustment of the sensitivity of the photoelectric sensor and the trigger delay of the rejection device when the vibration intensity or light change exceeds a preset threshold.

[0106] The specific adjustment method includes:

[0107] Collect environmental signals and record them in the form of a time series , where is the vibration intensity at time is the light intensity at time;

[0108] Use the root mean square value (RMS) to determine the quantization index of the vibration intensity , where is the sampling time window; is used to dynamically adjust the sensitivity of the photoelectric sensor.

[0109] To describe the amplitude of the light change, calculate the relative change rate of the light intensity , where and are the maximum and minimum values of the light intensity within the past time window , and is the average value of the light intensity.

[0110] Determine the dynamic adjustment function of the photoelectric sensor sensitivity , where is the initial sensitivity of the photoelectric sensor, is the influence coefficient used to control the impact of vibration and light changes on the sensitivity; the higher the vibration intensity, the more the sensitivity decreases exponentially, thereby reducing the possibility of false triggering.

[0111] Determine the dynamic adjustment function of the trigger delay of the rejection device , where is the initial trigger delay of the rejection device, is the influence coefficient used to control the impact of vibration and light changes on the trigger delay; the greater the light fluctuation, the corresponding increase in the trigger delay, avoiding false rejection actions caused by environmental light changes.

[0112] Example Six

[0113] This method constructs a dynamic prediction model based on the Long Short-Term Memory (LSTM) network to learn and predict the historical data of the vibration intensity quantization index and the relative change rate of the light intensity , and obtains the predicted values of the vibration intensity and the light intensity at future moments. According to the prediction results, the sensitivity of the photoelectric sensor and the trigger delay of the rejection device are adjusted in advance to improve the adaptability and real-time performance of the system to environmental changes.

[0114] Construct a dynamic prediction model based on the Long Short-Term Memory network, and use and historical values as inputs.

[0115] The network structure includes an input layer, an LSTM hidden layer, and an output layer. The input layer receives the time series of and ; the LSTM hidden layer learns the temporal correlation of the historical data through memory cells; the output layer: predicts and at future moments.

[0116] Use the historical vibration intensity and light change rate data to train the LSTM network, with the goal of minimizing the error between the predicted value and the true value .

[0117] The prediction model takes a time series as input and obtains a prediction result ;

[0118] According to the prediction and pre-adjust the sensitivity and trigger delay in advance; .

[0119] As time progresses, the vibration and light data are continuously updated, enabling the LSTM network to learn new environmental patterns in real time, ensuring the accuracy of the prediction results and the robustness of the model.

[0120] Compare the error between the predicted value and the true value, and use the backpropagation algorithm to update the network parameters to further improve the prediction accuracy.

[0121] Example Seven

[0122] A method for verifying the rejection result by eliminating the detection photoelectric sensor. Based on the count value of the encoder and the feedback signal of the elimination detection photoelectric sensor, it is determined whether the bottle cap has been successfully removed from the conveyor belt, which can accurately judge the rejection effect, and trigger an alarm or further processing when the rejection fails, ensuring the stability and accuracy of the system operation. The method for verifying the rejection result by eliminating the detection photoelectric sensor includes:

[0123] Determine the distance from the rejection area to the elimination detection photoelectric sensor , which is a fixed physical parameter between the rejection component and the detection area. And convert it into a pulse value , where is the pulse resolution of the encoder;

[0124] At the moment when the rejection component exerts a lateral force on the bottle cap, the PLC records the count value of the encoder when the rejection action occurs , and calculates the target count value at the rejection detection position ;

[0125] When the encoder count value reaches the target count value , the PLC obtains a feedback signal through the elimination detection photoelectric sensor. That is, when obtaining , the feedback signal of the elimination detection photoelectric sensor. If no trigger signal is detected, it indicates that the bottle cap has been successfully removed from the conveyor belt. If a trigger signal is detected, it is judged that the rejection fails, indicating that the bottle cap is still on the conveyor belt and the rejection fails.

[0126] When the rejection fails, the PLC immediately triggers corresponding measures: trigger an alarm signal to remind the operator; or stop the conveyor belt from running to prevent unqualified products from entering the subsequent production process.

[0127] In the description of this specification, the descriptions with reference to terms such as "one embodiment / way", "some embodiments / ways", "example", "specific example", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment / way or example are included in at least one embodiment / way or example of this application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment / way or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments / ways or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments / ways or examples described in this specification and the features of different embodiments / ways or examples.

[0128] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of these features. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0129] Those skilled in the art should understand that the above embodiments are only for clearly explaining the present invention and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications can be made on the basis of the above invention, and these changes or modifications are still within the scope of the present invention.

Claims

1. A verification and rejection method under high-speed conditions, characterized in that: The verification and rejection method comprises: The code reading trigger photoelectric sensor generates a trigger signal when detecting that the bottle cap passes through the trigger point; According to the trigger signal, the PLC triggers the code reader to read the data of the QR code on the bottle cap; The PLC receives the reading result of the code reader and compares it with the pre-stored data to generate the corresponding verification signal; Determine whether the bottle cap is qualified according to the verification signal. If it is qualified, it will not be rejected; if it is unqualified, a control signal will be applied to the rejection component; The rejection component applies lateral force to the defective products to remove the caps from the conveyor belt; The rejection results are verified by the rejection detection photoelectric sensor, and an alarm signal is issued or the conveyor belt is stopped when the defective products are not successfully rejected; The vibration intensity of the conveyor belt is detected by a vibration sensor, the light intensity near the code reading trigger photoelectric sensor and the rejection detection photoelectric sensor is detected by a light sensor, and the sensitivity of the photoelectric sensor and the trigger delay of the rejection device are adjusted when the vibration intensity or light change exceeds a preset threshold. The adjustment method includes: Collect environmental signals and record them in time series ,in, for The vibration intensity at the moment, for Light intensity at the time; Determine the quantitative index of vibration intensity ,in, is the sampling time window; Calculate the relative rate of change of light intensity ,in, and For the past time window The maximum and minimum values ​​of the internal light intensity, is the average light intensity; Dynamic adjustment function to determine the sensitivity of photosensors ,in, is the initial sensitivity of the photoelectric sensor, A coefficient used to control the effect of vibration and light changes on sensitivity; Dynamic adjustment function that determines the triggering delay of the reject device ,in, Delay for initial triggering of the reject device, A coefficient used to control the effect of vibration and light changes on the trigger delay.

2. A high-speed verification and rejection method according to claim 1, characterized in that: The method of triggering the code reader to read the data of the QR code on the bottle cap includes: Determine the distance from the code reading trigger photoelectric sensor to the code reading area , and convert it into a pulse value ,in, is the pulse resolution of the encoder; After receiving the trigger signal, the PLC records the current encoder count value and uses it as the code reading reference value ; Calculate the difference between the current encoder count value and the target position , ,in, It is the count value fed back by the encoder in real time; Calculate dynamic compensation error parameters , ,in, is the conveyor belt running speed, is the signal delay time of PLC, is the correction of the pulse value by the environmental error, and is the experience weight coefficient; like , the PLC sends a code reading control signal to the code reader.

3. A high-speed verification and rejection method according to claim 2, characterized in that: The depth camera is used to obtain the precise position of the bottle cap and the barcode reader is controlled to align with the bottle cap. The method includes: The depth camera collects the initial depth map of the code reading area ; Perform mean filtering and denoising on the depth values ​​in the depth map to obtain a depth map ; Setting Dynamic Depth Threshold and , ,in, is the median of the depth values ​​of the depth map, is the interquartile range of the depth values ​​of the depth map, is the dynamic adjustment coefficient; Binarize the depth map to obtain the mask map , ,in, Depth map Medium pixel coordinates The depth value of The mask image Medium pixel coordinates The binary depth value of Determine the center of mass of the bottle cap in pixel coordinates , ,in, is the area of ​​the bottle cap in pixel coordinates ; Get the two-dimensional physical coordinates of the bottle cap , ; Get the actual center position of the barcode reader , and calculate the error between the bottle cap position and the actual center position ,like Then read the QR code; otherwise adjust the actual center position of the code reader until it meets ,in, and is the allowable horizontal error range and vertical error range.

4. The high-speed verification and rejection method according to claim 3, characterized in that: Allowable horizontal error range , allowable vertical error range ,in, and is the static basic error range, is the conveyor belt speed, is the depth camera frame rate, is the speed influence coefficient; The method to adjust the actual center position of the code reader is: ,in, is the actual center position of the code reader after adjustment. To adjust the step size factor.

5. The high-speed verification and rejection method according to claim 1, characterized in that: Construct a dynamic prediction model based on long short-term memory network and and As input, we can get the prediction result ; Adjust sensitivity and trigger delay in advance based on prediction results; .

6. The high-speed verification and rejection method according to claim 1, characterized in that: Methods for verifying reject results with reject detection photoelectric sensors include: Determine the distance from the reject zone to the reject detection photoelectric sensor , and convert it into a pulse value ,in, is the pulse resolution of the encoder; PLC records the encoder count value when the rejection action occurs , calculate the target count value of the rejection detection position ; Get When the feedback signal of the photoelectric sensor is detected, if no trigger signal is detected, the rejection is judged to be successful; if a trigger signal is detected, the rejection is judged to be a failure.

7. The high-speed verification and rejection method according to claim 1, characterized in that: The inspection and rejection device comprises: a conveyor belt (1), a code reading trigger photoelectric sensor (2), a depth camera, a code reader (3), a rejection component (4), a rejection detection photoelectric sensor (5), an encoder (6) and a PLC; The code reading trigger photoelectric sensor (2), the code reader (3), the rejection component (4) and the rejection detection photoelectric sensor (5) are arranged in sequence along the conveying direction of the conveyor belt (1), and the conveyor belt (1) is used to convey bottle caps with two-dimensional codes on the conveyor belt (1); The code reading trigger photoelectric sensor (2) and the rejection detection photoelectric sensor (5) are both arranged on one side of the conveyor belt (1), and the detection direction is perpendicular to the conveying direction of the bottle caps; the depth camera and the code reader (3) are arranged in parallel and are located above the two-dimensional code reading area of ​​the bottle caps; The rejection component (4) applies a lateral force to the bottle caps located on the conveyor belt (1); The conveyor belt (1), the code reading trigger photoelectric sensor (2), the depth camera, the code reader (3), the rejection component (4), the rejection detection photoelectric sensor (5) and the encoder (6) are all electrically connected to the PLC.

8. The high-speed verification and rejection method according to claim 7, characterized in that: It also includes a vibration sensor and a light sensor, wherein the vibration sensor is arranged on the conveyor belt (1), and the light sensor is arranged near the code reading trigger photoelectric sensor (2) and the rejection detection photoelectric sensor (5), and the vibration sensor and the light sensor are both electrically connected to the PLC.

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