Positioning method and device for products on flow production line

Abstract

The invention relates to the technical field of assembly line positioning devices, and discloses a positioning method and device for products on an assembly line, the positioning device comprises a conveying rail, a conveying plate for conveying workpieces and a positioning assembly, the positioning assembly is composed of a positioning column and an RFID reader-writer, the bottom of the conveying plate is provided with an RFID tag and a pressure sensor, and the pressure sensor is connected with the conveying rail. The conveying plate is arranged above the conveying rail to move, one RFID reader-writer is arranged at the position where a workpiece needs to stay, the other RFID reader-writer is arranged at the front end of the position where the workpiece stays, and when the RFID reader-writer located at the position where the workpiece stays recognizes that the conveying plate with an RFID tag approaches, the positioning column is controlled to be lifted, the pressure sensor of the conveying plate is triggered, and the conveying plate is conveyed to the conveying rail. And when positioning is carried out through the two reader-writers, positioning is carried out again through physical contact, and the positioning precision is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of assembly line positioning devices, and in particular to a positioning method and device for assembly line products. Background Art

[0002] RFID positioning and identification is a technology that uses wireless radio frequency identification technology to accurately locate and identify the location of objects or people. RFID positioning and identification technology mainly relies on the wireless signal interaction between RFID tags and readers. RFID tags usually contain a unique identification code and an antenna, which can actively or passively send radio frequency signals. The reader receives the signal from the tag through the antenna and decodes and processes it. During the positioning process, the reader measures multiple parameters of the signal (such as intensity, phase, time difference, etc.), and uses these parameters combined with specific algorithms to calculate the location of the tag. A complete RFID system mainly consists of the following parts: RFID tags, which consist of a chip and an antenna. The chip contains the tag's unique identification code and memory, which is used to store relevant information of the object. The antenna is used to receive and send radio signals. RFID readers send wireless The RFID reader uses a radio signal to activate nearby RFID tags and receives signals returned by the tags. The reader can be connected to a network or computer to transmit the read tag information to the system for processing. The data processing system is responsible for receiving the tag information transmitted by the reader, parsing, processing and storing it, and calculating and displaying the position as needed. RFID positioning and identification technology can achieve fast and accurate data exchange between tags and readers without human intervention. This feature makes RFID positioning have unique advantages in automated and unmanned scenarios. The RFID system can identify multiple tags at the same time, greatly improving the positioning efficiency. This advantage is particularly evident in environments with dense tags, which helps to achieve efficient inventory management and logistics tracking. With the development of technology, RFID positioning technology has been able to achieve centimeter-level or even higher precision positioning, meeting the needs of many fields for precise positioning.

[0003] During processing and positioning on the assembly line, because there are many electrical equipment used, RFID signals are easily interfered by other wireless devices in a complex electromagnetic environment, resulting in reduced positioning accuracy or even failure. At the same time, the penetration of RFID signals is limited. For obstacles such as metal and liquid that may exist in the motor assembly line, the signal attenuates severely and cannot be effectively penetrated, resulting in a limited positioning range. When working on some assembly lines that require high-precision docking, it will cause certain impacts and require an increase in the number of subsequent maintenance and debugging. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the shortcomings of the prior art, the present invention provides a method and device for positioning products on an assembly line, which has the advantages of multiple positioning and solves the problem of interference with RFID identification signals on the assembly line.

[0006] (II) Technical solution

[0007] In order to achieve the above-mentioned multiple positioning purpose, the present invention provides the following technical solutions: a positioning method for production line products, step 1, an RFID tag is set at the bottom of the transport plate on the assembly line track, and an RFID reader is set before and at the position where the workpiece needs to stay, and the transport position of the workpiece on the assembly line is determined by the reader;

[0008] Step 2: When the RFID reader / writer at the front end recognizes that the transport plate with the RFID tag is approaching, it issues a command to turn on the RFID reader / writer at the workpiece stop position to start working;

[0009] Step 3: When the RFID reader / writer located at the workpiece stop position recognizes that the transport plate with the RFID tag is approaching, the positioning column is controlled to lift upward. A pressure sensor is provided at the bottom of the transport plate. When the positioning column is lifted and the pressure sensor is given pressure, the transport track stops moving, so that the workpiece stays at the corresponding position.

[0010] Step 4: When the workpiece is processed, a command is issued to make the positioning column fall, the transport plate continues to be transported along the assembly line, and the above steps are repeated.

[0011] A positioning device for production line products, comprising a transport track, a transport plate for transporting workpieces and a positioning component, wherein the positioning component consists of a positioning column and an RFID reader-writer, an RFID tag and a pressure sensor are arranged at the bottom of the transport plate, the transport plate is arranged to move above the transport track, and two RFID readers-writers are arranged, one RFID reader-writer is arranged at a place where the workpiece needs to stay, and the other is arranged at the front end of the place where the workpiece stays, when the RFID reader-writer located at the place where the workpiece stays recognizes that a transport plate with an RFID tag is approaching, the positioning column is controlled to be lifted, triggering the pressure sensor of the transport plate, so that the transport plate suspends transportation.

[0012] Preferably, the positioning column is composed of a sleeve and an airbag, the sleeve is arranged on the outer ring of the positioning column and is lifted by the expansion of the airbag, and the outer ring of the airbag is provided with an annular cylinder.

[0013] Preferably, a bottom notch having the same shape as the sleeve is provided at the bottom of the transport plate, and the pressure sensor is arranged inside the bottom notch.

[0014] Preferably, an inclined sliding groove is provided on one side of the bottom notch toward the positioning column.

[0015] Preferably, the airbag is divided into two left and right airbags, and the two airbags have the same volume and independent internal spaces, and an air pressure sensor is arranged inside each airbag.

[0016] Preferably, the RFID reader / writer arranged at the workpiece stopping place is an inductive coupling reader / writer, the RFID reader / writer arranged at the front end of the workpiece stopping place is an electromagnetic backscatter coupling reader / writer, and RFID tags corresponding to two different types of readers / writers are arranged under the transport plate.

[0017] (III) Beneficial effects

[0018] Compared with the prior art, the present invention provides a method and device for positioning products on an assembly line, which has the following beneficial effects:

[0019] 1. The positioning method and device for assembly line products, by utilizing the rapid identification capability of RFID technology, the system can quickly and accurately locate the transport plate with a specific RFID tag and the workpiece on it, which greatly shortens the waiting time of the workpiece on the production line, allowing the workpiece to enter the processing or testing stage more quickly. The setting of dual RFID readers (front-end detection and back-end precise identification) ensures the accuracy of positioning and avoids repeated positioning or wrong positioning caused by a single identification error. Once the workpiece is accurately located and paused at the specified position, the assembly line immediately stops moving, allowing the processing equipment to immediately process or detect the workpiece. This seamless connection reduces interruptions and waiting time in the production process and improves overall production efficiency. The front-end RFID reader is mainly responsible for detecting the transport plate that is about to arrive at the stop point, while the back-end RFID reader is responsible for precise identification and control when the workpiece arrives at the specified position. This dual verification mechanism ensures the accuracy and reliability of positioning. Inductively coupled RFID readers (suitable for close-range identification) and electromagnetic backscatter coupled RFID readers (suitable for The combined use of RFID reader / writer and long-distance preliminary positioning improves the accuracy and stability of positioning. The inductively coupled reader / writer can provide high-precision identification at close range, while the electromagnetic backscatter coupled reader / writer can perform preliminary positioning in a wider area. The addition of pressure sensors further enhances the reliability of verification. When the positioning column is lifted and triggers the pressure sensor, the system can confirm that the transport plate has reached the predetermined position and is reliably fixed. The positions of the RFID reader / writer and the positioning column can be flexibly adjusted according to the specific needs of the production line to adapt to workpieces of different sizes and different processing requirements. This flexibility enables the production line to cope with diverse production needs and improves the adaptability and scalability of the production line. Through precise positioning, the system can ensure that the workpiece always remains in the predetermined position during transportation, reducing collisions or falling accidents that may occur due to inaccurate positioning, which improves production safety and protects equipment and workpieces from damage. The system can monitor the position and status of the workpiece in real time and send out alarm signals in time when abnormal conditions occur, which helps production managers to respond and deal with problems quickly to avoid the expansion of accidents and increased losses.

[0020] 2. The positioning method and device for the product on the assembly line, through the expansion of the airbag, the sleeve can stably and balancedly lift the transport plate to ensure the precise position of the product on the production line, which is conducive to the smooth progress of subsequent processing or assembly steps, and reduces errors and rework caused by inaccurate positioning. The annular cylinder of the outer ring of the airbag limits the shape and expansion direction of the airbag to ensure that the lifting process is smooth and without fluctuations, avoiding impact and damage to the transport plate or the product, and the inflation and deflation process of the airbag is conducive to repeated movement. The airbag is divided into two left and right airbags, and the two airbags have the same volume and independent internal space. The air pressure sensor set inside each independent airbag can realize The air pressure changes are monitored in real time. When the sleeve is lifted too slowly or too quickly, the air pressure sensor can quickly capture the air pressure difference to determine the offset direction during the lifting process. The data feedback from the air pressure sensor can automatically adjust the inflation volume of the airbag to keep the sleeve lifted in a balanced manner. This automatic adjustment mechanism can effectively reduce the positioning error caused by improper human operation or equipment failure. The bottom notch of the transport plate with the same shape as the sleeve and the inclined slide groove toward the positioning column can reduce the friction and collision with the bottom of the transport plate during the lifting of the sleeve, which helps to protect the transport plate and product surface from damage while reducing noise and vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

[0022] Figure 2 It is a detailed schematic diagram of the positioning component of the present invention;

[0023] Figure 3 It is a top view of the structure of the present invention;

[0024] Figure 4 This is a schematic diagram of the bottom of the transport plate of the present invention;

[0025] Figure 5 Schematic diagram of the positioning column triggering pressure sensor of the present invention Figure 1 ;

[0026] Figure 6 Schematic diagram of the positioning column triggering pressure sensor of the present invention Figure 2 ;

[0027] Figure 7 The schematic diagram of the positioning column structure of the present invention is shown in FIG. Figure 1 ;

[0028] Figure 8 The schematic diagram of the positioning column structure of the present invention is shown in FIG. Figure 2 ;

[0029] Fig. 9 It is a detailed schematic diagram of the airbag of the present invention.

[0030] In the figure: 1, transport track; 2, transport plate; 11, positioning assembly; 21, bottom notch; 22, RFID tag; 111, positioning column; 112, RFID reader; 211, pressure sensor; 1111, sleeve; 1112, airbag. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] See also Figure 1-Figure 2 , Figure 4-Figure 6 , a positioning method and device for production line products include a transport track 1, a transport plate 2 for transporting workpieces, and a positioning component 11, wherein the positioning component 11 is composed of a positioning column 111 and an RFID reader 112, an RFID tag 22 and a pressure sensor 211 are arranged at the bottom of the transport plate 2, the transport plate 2 is arranged to move above the transport track 1, and two RFID readers 112 are arranged, one RFID reader 112 is arranged at a place where the workpiece needs to stay, and the other is arranged at the front end of the place where the workpiece stays, when the RFID reader 112 located at the place where the workpiece stays recognizes that the transport plate 2 with the RFID tag 22 is approaching, the positioning column 111 is controlled to be lifted, and the pressure sensor 211 of the transport plate 2 is triggered, so that the transport plate 2 stops transporting.

[0033] When the RFID tag 22 enters the RF field of the reader, the antenna in the tag will receive the RF signal emitted by the reader and use it as an energy source to activate the circuit inside the tag. Subsequently, the tag will send the information stored in itself back to the reader by backscattering to complete the information exchange. An RFID tag 22 is installed at the bottom of each transport board of the assembly line. These tags contain the unique identification information of the transport board 2 and the workpiece on it. Subsequently, RFID readers 112 are installed in front of and at the position where the workpiece needs to stop for processing in the assembly line. The front-end reader is mainly used to detect the transport board 2 that is about to arrive at the stop point, while the rear-end reader is responsible for accurate identification and control when the workpiece arrives at the specified position. When the transport board 2 on the assembly line moves forward with the workpiece, the RFID tag 22 at its bottom gradually approaches the RFID reader 112 set at the front end, and the reader starts to scan the RFID tags 22 in the surrounding environment. Once the transport board with the target RFID tag 22 is successfully identified, the reader immediately sends a command signal to the RFID reader 112 at the back end (i.e., where the workpiece stops) through the system network, notifying it to prepare to start working. After receiving the command sent by the front-end reader 112, the RFID reader 112 at the workpiece stop enters the working state and starts to continuously scan the RFID tags 22 within its identification range. When it detects that the transport board with the same RFID tag 22 is approaching and entering When the workpiece enters the precise identification range, the reader triggers the positioning control mechanism, which includes controlling a series of positioning posts 111 to lift upward. A pressure sensor is also installed at the bottom of the transport plate to detect the pressure applied when the positioning posts are lifted. Once the pressure sensor 211 detects sufficient pressure, it means that the transport plate 2 has reached the predetermined position. At this time, the control system of the assembly line transport track receives a signal from the pressure sensor 211 and immediately suspends the movement of the transport track to ensure that the workpiece can accurately stay at the corresponding processing or testing position. When the workpiece completes all necessary processing or testing steps at the stop position, the system will receive a completion signal. According to this signal, the control system will issue an instruction again to make the positioning posts 111 falls slowly, releasing the fixation on the transport plate 2. Once the pressure sensor under the transport plate 2 detects that the pressure disappears, it indicates that the positioning column 111 has been completely reset, and the assembly line transport track immediately resumes movement. The transport plate continues to move forward along the assembly line, carrying the processed workpiece to the next processing station or destination. During the whole process, the system realizes the precise control and automated management of the workpiece transportation position on the assembly line by continuously executing the above steps in a loop, greatly improving production efficiency and accuracy. The lifting of the positioning column 111 is gradually carried out as the transport plate 2 approaches. When the transport plate 2 reaches the set position, the positioning column 111 can also be lifted to the set height, triggering the pressure sensor 211 to achieve multiple positioning.

[0034] See also Figure 4-Figure 8The positioning column 111 is composed of a sleeve 1111 and an airbag 1112. The sleeve 1111 is arranged on the outer ring of the positioning column 111 and is lifted by the expansion of the airbag 1112. The outer ring of the airbag 1112 is provided with an annular cylinder, and the shape and expansion direction of the airbag 1112 are limited by the annular cylinder. In addition, due to the air pressure characteristics, the lifting of the sleeve 1111 can be balanced and stable. The bottom of the transport plate 2 is provided with a bottom notch 21 with the same shape as the sleeve 1111. The pressure sensor 211 is arranged inside the bottom notch 21. The bottom notch 21 is provided with an inclined sliding groove on one side close to the positioning column 111. The sliding groove can avoid friction and collision with the bottom of the transport plate 2 during the lifting process of the sleeve 1111 of the positioning column 111.

[0035] See also Fig. 9 The airbag 1112 is divided into two left and right airbags, and the two airbags 1112 have the same volume and independent internal spaces. An air pressure sensor is arranged inside each airbag 1112. When the sleeve 1111 is lifted too slowly or too quickly, the sleeve 1111 will be subjected to an unbalanced squeezing force, causing the air pressure changes generated by the two airbags 1112 to be different. The air pressure sensor can be used to detect and calculate the direction in which the deviation error has occurred, so that readjustment can be made conveniently.

[0036] The RFID reader / writer 112 arranged at the workpiece stop position is an inductive coupling reader / writer, the RFID reader / writer 112 arranged at the front end of the workpiece stop position is an electromagnetic backscatter coupling reader / writer, and two RFID tags 22 corresponding to two different types of readers / writers are arranged under the transport plate 2. Inductive coupling, also known as magnetic coupling, has a working principle similar to that of a transformer. In an inductive coupling system, the reader / writer emits electromagnetic waves of a certain frequency, which form an alternating magnetic field in space. When the RFID tag 22 (usually including a coil and a chip) enters this magnetic field range, the coil inside it will sense the magnetic field and generate an induced current, thereby driving the tag chip to work and realize communication with the reader / writer. Inductive coupling is suitable for close-range identification scenarios and has high identification accuracy and stability. Since the inductive coupling system is relatively simple, it is relatively low in cost and suitable for large-scale deployment. At close range, the inductive coupling system is less affected by environmental interference and can ensure accurate data transmission. The electromagnetic backscatter coupling method is more common in high-frequency and microwave bands. In this coupling method, the electromagnetic waves emitted by the reader are irradiated onto the RFID tag 22, and the tag scatters the electromagnetic waves back to the reader through its antenna. The reader receives and analyzes these scattered electromagnetic waves to obtain the information in the tag. The electromagnetic backscatter coupling method is suitable for long-distance identification scenarios and can cover a wider area. At high-frequency and microwave bands, the electromagnetic backscatter coupling method can achieve a higher data transmission rate and meet application scenarios with higher real-time requirements. After the electromagnetic backscatter coupling method performs preliminary rapid positioning, when approaching the workpiece stop point, an inductively coupled reader is used for precise positioning. By alternating between the two methods, resource utilization is saved and the calculation of background data is simplified.

[0037] Working principle: When the RFID tag 22 enters the RF field of the reader, the antenna in the tag will receive the RF signal emitted by the reader and use it as an energy source to activate the circuit inside the tag. Subsequently, the tag will send the information stored in itself back to the reader by backscattering to complete the information exchange. An RFID tag 22 is installed at the bottom of each transport board of the assembly line. These tags contain the unique identification information of the transport board 2 and the workpiece on it. Subsequently, RFID readers 112 are installed in front of and at the position where the workpiece needs to stop for processing in the assembly line. The front-end reader is mainly used to detect the transport board 2 that is about to arrive at the stop point, while the rear-end reader is responsible for accurate identification and control when the workpiece arrives at the specified position. As the transport board 2 on the line moves forward with the workpiece, and the RFID tag 22 at its bottom gradually approaches the RFID reader / writer 112 set at the front end, the reader / writer starts to scan the RFID tags 22 in the surrounding environment. Once the transport board with the target RFID tag 22 is successfully identified, the reader / writer immediately sends a command signal to the RFID reader / writer 112 at the rear end (i.e., where the workpiece stops) through the system network, notifying it to prepare to start working. After receiving the command sent by the front-end reader / writer, the RFID reader / writer 112 at the workpiece stop position enters the working state and starts to continuously scan the RFID tags 22 that enter its identification range. When it detects that the transport board with the same RFID tag 22 approaches and enters the precise identification range, the reader / writer The device triggers the positioning control mechanism, which includes controlling a series of positioning posts 111 to lift upward. A pressure sensor is also installed at the bottom of the transport plate to detect the pressure applied when the positioning posts are lifted. Once the pressure sensor 211 detects sufficient pressure, it means that the transport plate 2 has reached the predetermined position. At this time, the control system of the assembly line transport track receives a signal from the pressure sensor 211 and immediately pauses the movement of the transport track to ensure that the workpiece can accurately stay at the corresponding processing or testing position. When the workpiece completes all necessary processing or testing steps at the stop position, the system will receive a completion signal. According to this signal, the control system will issue an instruction again to make the positioning posts 111 fall slowly to release the fixation on the transport plate 2. Once the transport plate 2 is moved, the control system will stop the movement of the transport track. The pressure sensor under the conveyor plate 2 detects that the pressure disappears, indicating that the positioning column 111 has been completely reset, and the assembly line transport track immediately resumes movement. The transport plate continues to move forward along the assembly line, carrying the processed workpiece to the next processing station or destination. During the whole process, the system realizes the precise control and automatic management of the transport position of the workpiece on the assembly line by continuously executing the above steps in a loop, greatly improving the production efficiency and accuracy. The RFID reader 112 arranged at the workpiece stop is an inductively coupled reader, and the RFID reader 112 arranged at the front end of the workpiece stop is an electromagnetic backscattering coupled reader, and two RFID tags 22 corresponding to two different types of readers are arranged under the transport plate 2, inductively coupled,Also known as magnetic coupling, its working principle is similar to that of a transformer. In an inductive coupling system, the reader emits electromagnetic waves of a certain frequency, which form an alternating magnetic field in space. When the RFID tag 22 (usually including a coil and a chip) enters this magnetic field range, the coil inside it will sense the magnetic field and generate an induced current, thereby driving the tag chip to work and achieve communication with the reader. Inductive coupling is suitable for close-range identification scenarios and has high identification accuracy and stability. Since the inductive coupling system is relatively simple, it is low in cost and suitable for large-scale deployment. At close range, the inductive coupling system is less affected by environmental interference and can ensure accurate data transmission. The electromagnetic backscatter coupling method is more effective in high-frequency and microwave bands. Common, in this coupling mode, the electromagnetic waves emitted by the reader are irradiated onto the RFID tag, and the tag scatters the electromagnetic waves back to the reader through its antenna. The reader receives and analyzes these scattered electromagnetic waves to obtain the information in the tag. The electromagnetic backscatter coupling method is suitable for long-distance identification scenarios and can cover a wider area. In the high-frequency and microwave frequency bands, the electromagnetic backscatter coupling method can achieve a higher data transmission rate and meet the application scenarios with high real-time requirements. After the electromagnetic backscatter coupling method performs preliminary rapid positioning, when approaching the workpiece stop, the inductive coupling reader is used for precise positioning. By alternating the use of methods, the utilization of resources is saved and the calculation of background data is simplified. ,

[0038] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A positioning method for production line products, characterized by: Step 1: An RFID tag is set at the bottom of the transport plate on the assembly line track, and an RFID reader is set before and at the position where the workpiece needs to stay, and the transport position of the workpiece on the assembly line is determined by the reader; Step 2: When the RFID reader / writer at the front end recognizes that the transport plate with the RFID tag is approaching, it issues a command to turn on the RFID reader / writer at the workpiece stop position to start working; Step 3: When the RFID reader / writer located at the workpiece stop position recognizes that the transport plate with the RFID tag is approaching, the positioning column is controlled to lift upward. A pressure sensor is provided at the bottom of the transport plate. When the positioning column is lifted and the pressure sensor is given pressure, the transport track stops moving, so that the workpiece stays at the corresponding position. Step 4: When the workpiece is processed, a command is issued to make the positioning column fall, the transport plate continues to be transported along the assembly line, and the above steps are repeated.

2. A positioning device for implementing a positioning method for production line products as described in claim 1, comprising a transport track (1), a transport plate (2) for transporting workpieces and a positioning assembly (11), wherein the positioning assembly (11) is composed of a positioning column (111) and an RFID reader (112), an RFID tag (22) and a pressure sensor (211) are arranged at the bottom of the transport plate (2), and the transport plate (2) is arranged to move above the transport track (1), characterized in that: Two RFID readers (112) are provided, one RFID reader (112) is provided at the place where the workpiece needs to stay, and the other is provided at the front end of the place where the workpiece stays. When the RFID reader (112) located at the place where the workpiece stays recognizes that a transport plate (2) with an RFID tag (22) is approaching, the positioning column (111) is controlled to be lifted, triggering a pressure sensor (211) of the transport plate (2), so that the transport plate (2) stops transporting.

3. A positioning device for production line products according to claim 2, characterized in that: The positioning column (111) is composed of a sleeve (1111) and an airbag (1112); the sleeve (1111) is arranged on the outer ring of the positioning column (111) and is lifted by the expansion of the airbag (1112); and the outer ring of the airbag (1112) is provided with an annular cylinder.

4. A positioning device for production line products according to claim 3, characterized in that: The bottom of the transport plate (2) is provided with a bottom notch (21) having the same shape as the sleeve (1111), and the pressure sensor (211) is arranged inside the bottom notch (21).

5. A positioning device for production line products according to claim 4, characterized in that: The bottom notch (21) is provided with an inclined sliding groove on one side close to the positioning column (111).

6. A positioning device for production line products according to claim 4, characterized in that: The airbag (1112) is divided into two, left and right, and the two airbags (1112) have the same volume and independent internal spaces, and an air pressure sensor is arranged inside each airbag (1112).

7. A positioning device for production line products according to claim 1, characterized in that: The RFID reader / writer (112) arranged at the workpiece stopping position is an inductive coupling reader / writer, the RFID reader / writer (112) arranged at the front end of the workpiece stopping position is an electromagnetic backscatter coupling reader / writer, and two RFID tags (22) corresponding to two different types of readers / writers are arranged under the transport plate (2).

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