Apparatus for measuring the length of straight T-bar

Abstract

The present invention relates to a device for measuring the length of a straight T-bar, comprising: a conveyor (10) that causes the transport of the T-bar between processes; a first measuring member (20) installed on one side of the conveyor (10) and having a camera module (23) on an LM guide (21); a second measuring member (30) installed on the other side of the conveyor (10) and having a camera module (33) on an LM guide (31); a third measuring member that detects the transport state of the T-bar and the camera module (23)(33); and a controller (50) that inputs a signal from the detection member and calculates the length of the T-bar using a set algorithm. Accordingly, it is expected that man-hours can be reduced and the reliability of measured length values ​​ensured based on the automated measurement system, while also enabling the exploration and identification of areas for improvement to enhance the accuracy of basic assembly components.

Description

Technology Field

[0001] The present invention relates to a straight T-bar length measuring device, and more specifically, to a straight T-bar length measuring device that performs precise length measurement of a component manufactured in a T-bar manufacturing plant within a yard by combining machine vision imaging and transfer system control technology. Background Technology

[0002] Currently, T-bar assembly at shipbuilding sites is performed by conveyor systems for each process; however, frequent rework occurs in subsequent processes due to a lack of dimensional accuracy control for components at each stage. This is attributed to the limitations of measuring various component dimensions using measuring tapes and jigs.

[0003] In other words, since there is no standard measurement method for large members exceeding 21m in length, such as T-bars, measurements are currently taken using tape measures; however, the precision of tape measures is 20m according to KS Grade 1 standards. 2.2mm tolerance for already assembled members It is unsuitable as a measurement method as it exceeds 2mm. When using a tape measure, the tolerance of the measuring instrument exceeds the tolerance of the workpiece, and additional errors are introduced depending on the force applied by the worker.

[0004] Regarding countermeasures for this, reference may be made to prior patents such as Korean Utility Model Registration Publication No. 2012-0000119 and Korean Registered Patent Publication No. 1394634.

[0005] The former includes a body with a tape measure mounting surface exposed at the top; a fixing block inserted into a cutting groove and fastened to press the tape measure in close contact with the tape measure mounting surface; a magnetic member provided on a horizontal or vertical plate to provide adhesive force by magnetic force; and a handle installed on the horizontal or vertical plate.

[0006] The latter includes the step of calculating a first distance value to an image position for a first end on a first pose of a stereo camera, the step of calculating a second distance value to an image position for a second end of a rotated structure, and the step of calculating the distance between both ends of the structure using the first distance value and the second distance value.

[0007] However, since the former is based on a measuring tape, it is difficult to eliminate measurement errors, and since the latter is based on a single stereo camera, it is difficult to guarantee the precision of T-bar length measurement. Prior art literature

[0008] Korean Utility Model Publication No. 2012-0000119 "Device for Measuring Plate Length" (Publication Date: Jan. 4, 2012) Korean Registered Patent Publication No. 1394634 "Method and Apparatus for Measuring Length of Large Structures Using Stereo Vision and Rotation Angle" (Publication Date: May 13, 2014) The problem to be solved

[0009] The objective of the present invention, aimed at improving the aforementioned conventional problems, is to combine machine vision imaging technology and appropriate transfer system control technology with the motivation to increase the dimensional accuracy of T-bar length measurement, thereby [determining] the absolute length of large members exceeding 20m without affecting the workability of the current process. The purpose is to provide a straight T-bar length measuring device that measures precisely with an error of within 1.0 mm. means of solving the problem

[0010] To achieve the above objective, the present invention comprises a device for measuring the length of a straight T-bar, comprising: a conveyor that causes the transport of the T-bar between processes; a first measuring member installed on one side of the conveyor and having a camera module on an LM guide; a second measuring member installed on the other side of the conveyor and having a camera module on an LM guide; a third measuring member that detects the transport state of the T-bar and the camera module; and a controller that inputs a signal from the detection member and calculates the length of the T-bar using a set algorithm.

[0011] According to the detailed configuration of the present invention, the camera module is characterized by generating CCD pixels having origins and edges in images of the face and web of the T-bar.

[0012] According to the detailed configuration of the present invention, the third measuring member is characterized by comprising a transfer detector that detects the transfer position of a T-bar on a conveyor, a departure detector that detects whether the T-bar deviates from a set area of ​​the conveyor, and a position detector that detects the distance between two camera modules.

[0013] According to the detailed configuration of the present invention, the controller is characterized by calculating the length of the T-bar by adding the coordinates of the edge with respect to the origin on the image to the distance coordinates between the two camera modules.

[0014] According to the detailed configuration of the present invention, the controller is characterized by being connected to control an air injector that sprays air onto a camera module and an aligner that aligns a T-bar to a set area. Effects of the invention

[0015] As described above, according to the present invention, additional reduction in labor for measurement activities can be expected based on an automated measurement system, and the reliability of the measured length values ​​is ensured. Furthermore, the measured values ​​are constructed as big data to enable the identification of trends, thereby allowing for the identification and derivation of improvements to enhance the accuracy of basic assembly components. Brief explanation of the drawing

[0016] FIG. 1 is a planar diagram showing a device according to the present invention. FIG. 2 is a configuration diagram showing the device according to the present invention from the front. FIG. 3 is a configuration diagram showing the device according to the present invention from the side. FIG. 4 is a configuration diagram showing an enlarged portion of FIG. 1. FIG. 5 is a block diagram showing the controller circuit of the device according to the present invention. Specific details for implementing the invention

[0017] Hereinafter, embodiments of the present invention will be described in detail based on the attached drawings.

[0018] The present invention proposes a device for measuring the length of a straight T-bar. The purpose is to resolve the drawbacks of frequent rework, such as re-cutting and additional welding, occurring in subsequent processes due to the length defects of the T-bar member mounted on the main plate.

[0019] Referring to Fig. 1, the T-bar (TB) being transported through a painting machine is used, but is not limited thereto.

[0020] According to the present invention, the conveyor (10) has a structure that causes the transfer of the T-bar between processes.

[0021] In FIG. 1, a large T-bar with a length exceeding 21 m is transported from a painting machine via a conveyor (10). The conveyor (10) may be configured in multiple units to ensure continuity from the painting machine process to a subsequent process. The conveyor (10) is equipped with multiple rollers (11) and drives the transport of the T-bar through a driving motor. A fence (13) is installed for safety at the part where the conveyor (10) is connected. In particular, the fence (13) prevents collision with the worker when the second measuring member (30), described later, is transported for measuring the T-bar.

[0022] In addition, according to the present invention, a first measuring member (20) equipped with a camera module (23) on an LM guide (21) is installed on one side of the conveyor (10).

[0023] Referring to FIGS. 1 and 2, an LM guide (21), a camera module (23), etc., constituting the first measuring member (20) are shown. The first measuring member (20) has the function of machine vision and is positioned on the downstream side of the conveyor (10) based on the transport direction of the taba. The LM guide (21) is connected to the first actuator (25) and installed to transport the camera module (23) back and forth within a set section. The camera module (23) is configured to include a frame supporting the CCD camera, lighting, a reflector (27) (37), etc.

[0024] In addition, according to the present invention, a second measuring member (30) equipped with a camera module (33) on an LM guide (31) is installed on the other side of the conveyor (10).

[0025] Referring to FIGS. 2 and 3, an LM guide (31), a camera module (33), a second actuator (35), etc., constituting the second measuring member (30) are shown. The second measuring member (30) has the function of machine vision and is positioned on the upstream side of the conveyor (10) based on the transport direction of the taba. The LM guide (31) is connected to the second actuator (35) and installed to transport the camera module (33) back and forth within a set section. The camera module (33) is configured to include a frame supporting the CCD camera, lighting, a reflector (27) (37), etc.

[0026] According to the detailed configuration of the present invention, the camera module (23)(33) is characterized by generating CCD pixels having origins and edges in images of the face and web of the T-bar.

[0027] FIG. 3 shows a state in which camera modules (23)(33) are positioned on the upper surface and side of a T-bar (TB) being transported on a conveyor (10). An image of the face is acquired on the upper surface of the T-bar, and an image of the web is acquired on the side of the T-bar. The camera modules (23)(33) achieve a resolution capable of detecting the edges of the T-bar from images acquired by taking a picture with a CCD camera having an absolute origin.

[0028] In addition, according to the present invention, the third measuring member is structured to detect the transfer state of the T-bar and the camera module (23)(33).

[0029] The third measuring member generates a signal to guide the T-bar to stop for measurement after it has been transported to a set position on the conveyor (10). If the transported position of the T-bar deviates from the set range, there is a risk of inaccuracy in the measurement as well as interference or collision with other components. In addition, data regarding the transported position (coordinates) of the camera modules (23)(33) of the first measuring member (20) and the second measuring member (30) must also be secured.

[0030] According to the detailed configuration of the present invention, the third measuring member is characterized by having a transfer detector (41) that detects the transfer position of a T-bar on a conveyor (10), a departure detector (43) that detects whether the T-bar deviates from a set area of ​​the conveyor (10), and a position detector (45) that detects the distance between two camera modules (23) (33).

[0031] In FIGS. 1 to 3, a transfer detector (41), a detachment detector (43), and a position detector (45) constituting the third measuring member are shown. The transfer detector (41) is equipped with a limit switch or an optical sensor on the upstream and downstream sides of the conveyor (10), respectively, and detects the start and end of the entry of the T-bar. The downstream transfer detector (41) generates a signal to prevent the first measuring member (20) and the second measuring member (30) from operating when the T-bar member of 15m or less stops. That is, it can be limited to T-bar members in the 15~21m range, which account for most of the total production volume. The detachment detector (43) is equipped with a pair of laser sensors parallel in the longitudinal direction on the upper surface of the conveyor (10) and detects the state of detachment during the transfer and stopping process of the T-bar. The position detector (45) detects the distance between the CCD camera origins of the two camera modules (23) (33) by mounting an encoder on the actuator (25) (35).

[0032] In addition, according to the present invention, the controller (50) has a structure that inputs a signal from the detection member and calculates the length of the T-bar using a set algorithm.

[0033] Referring to FIG. 5, the first measuring member (20), the second measuring member (30), the third measuring member, etc. are connected to the controller (50). The controller (50) is composed of a microcomputer circuit equipped with a microprocessor, memory, and an input / output interface. A transfer detector (41), a deviation detector (43), a position detector (45), etc. are connected to the input interface of the controller (50). A high-resolution CCD camera sensor and a drive unit (25)(35) equipped with a servo motor capable of achieving an appropriate level of speed are connected to the output interface of the controller (50). A software algorithm for processing images from the camera module (23)(33) is stored in the memory of the controller (50) and executed by the microprocessor.

[0034] According to the detailed configuration of the present invention, the controller (50) is characterized by calculating the length of the T-bar by adding the coordinates of the edge with respect to the origin on the image to the distance coordinates between the two camera modules (23) (33).

[0035] A T-bar is transported by the drive motor of the conveyor (10), and the camera module (23)(33) is moved according to the set conditions to measure the step (edge) of the T-bar's face and the web. More specifically, the first measuring member (20) moves a certain distance from the initial position (origin) and stops. The stopping position can be set to the lighting position of the T-bar's face. Subsequently, the step is measured at the front / rear end of the transported T-bar. The origin on the screen of the camera capturing the face edge and the origin on the screen of the camera capturing the web edge are accurately aligned in the initial setting.

[0036] However, the T-bars differ in length and do not stop at an accurate position on the conveyor (10). It is also difficult for the camera modules (23)(33) moving along the LM guides (21)(31) to accurately align the origin with the edge of the T-bar. The controller (50) calculates the pixel error between the origin and the edges of the face and web, respectively, from the images taken at the front and rear ends of the T-bar, and finally calculates the step difference between the face edge and the web edge at the front and rear ends. In this process, using a position detector (45) that measures the distance between the two camera modules (23)(33) is advantageous in terms of improving reliability.

[0037] According to the detailed configuration of the present invention, the controller (50) is characterized by being connected to control an air blower (52) that sprays air onto a camera module (23)(33) and a reflector (27)(37), and an aligner (55) that aligns a T-bar to a set area.

[0038] In FIGS. 1 and 3, an air blower (52) controlled by a controller (50) appears on a conveyor (10). The air blower (52) blows clean air under conditions set so that dust or foreign matter does not accumulate on the camera module (23)(33) and the reflector (27)(37). In particular, in the case of the T-bar discharged from the paint machine, there is a high risk that paint dust will accumulate on the reflector (27)(37), causing measurement errors as well as malfunctions. Of course, the air blower (52) can be operated continuously without a separate signal.

[0039] Referring to FIG. 4, an alignment device (55) controlled by a controller (50) appears on the conveyor (10). It is installed on one side and the other side of the conveyor (10) adjacent to the detection area of ​​the deviation detector (43). The alignment device (55) is composed of a pressure cushion and an operating cylinder and can correct the transport and stopping position of the T-bar. Of course, the alignment distance of the alignment device (55) is set differently depending on the specifications of the T-bar.

[0040] In this way, the present invention can expect to improve the accuracy of basic components, including T-bars, and increase productivity by linking the conveyor (10), the first measuring member (20), the second measuring member (30), the third measuring member, and the controller (50).

[0041] Error values ​​that must be taken into account when measuring with a tape measure in the past 2.2mm (KS Grade 1) It can be minimized to within 1.0mm.

[0042] It is obvious to those skilled in the art that the present invention is not limited to the described embodiments and can be modified and varied in various ways without departing from the spirit and scope of the invention. Accordingly, such variations or modifications should be considered to fall within the scope of the claims of the present invention. Explanation of the symbols

[0043] 10: Conveyor 11: Roller 13: Fence 20: First measuring member 21: LM guide 23: Camera module 25: First actuator 27, 37: Reflector 30: Second measuring member 31: LM guide 33: Camera module 35: Second actuator 41: Transfer detector 43: Deviation detector 45: Position detector 50: Controller 52: Air blower 55: Aligner

Claims

Claim 1 A device for measuring the length of a straight T-bar, comprising: a conveyor (10) that causes the transport of the T-bar between processes; a first measuring member (20) installed on one side of the conveyor (10) and having a camera module (23) on an LM guide (21); a second measuring member (30) installed on the other side of the conveyor (10) and having a camera module (33) on an LM guide (31); and a third measuring member that detects the transport status of the T-bar and the camera module (23)(33). A straight T-bar length measuring device comprising: a controller (50) that inputs signals from the first to third measuring members (20, 30) and calculates the length of the T-bar using a set algorithm; wherein the third measuring member is equipped with a transfer detector (41) that detects the transfer position of the T-bar on the conveyor (10), a deviation detector (43) that detects whether the T-bar deviates from a set area of ​​the conveyor (10), and a position detector (45) that detects the distance between two camera modules (23) (33); wherein the controller (50) calculates the length of the T-bar by adding the coordinates of the edge relative to the origin on the image to the distance coordinates between the two camera modules (23) (33), and is connected to control an air blower (52) that sprays air onto the camera modules (23) (33) and the reflector (27) (37), and an alignment device (55) that aligns the T-bar to a set area. Claim 2 A straight T-bar length measuring device according to claim 1, wherein the camera module (23)(33) generates CCD pixels having origins and edges in an image of the face and web of the T-bar. Claim 3 delete Claim 4 delete Claim 5 delete

Images