A body positioning measurement system and method

Abstract

The present application relates to the technical field of vehicle body positioning, and particularly relates to a vehicle body positioning measurement system and method, wherein the vehicle body positioning measurement system comprises four visual sensors arranged around a measured vehicle body for detecting feature point information on the measured vehicle body; a host computer in communication connection with the visual sensors for receiving the feature point information, extracting feature contour information, and comparing the feature contour information with pre-recorded vehicle body zero reference position information to obtain a position offset of the measured vehicle body; and an industrial robot in communication connection with the host computer to obtain the position offset and automatically correct a process track of the industrial robot; and the present application effectively solves the technical problem of line shutdown caused by super-tolerance parts in the prior art, which leads to serious waste of production capacity.

Description

Technical Field

[0001] This invention relates to the field of vehicle body positioning technology, and more specifically to a vehicle body positioning measurement system and method. Background Technology

[0002] Automobile manufacturing is a mass production line operation, including four major workshops: stamping, welding, painting, and final assembly. Taking the welding and final assembly workshops as examples, after the car body is transported to its position by the conveyor line or conveyor trolley, the robot receives the signal and begins to perform welding, gluing, marking, and other tasks. However, due to factors such as manufacturing errors, positioning errors, and positioning wear caused by the conveyor line and multiple sets of cars, each car body will have a certain positional change and posture rotation after it arrives. This results in a positional difference between the robot tool coordinate point and the actual working point of the car body, leading to intermittent quality accidents and affecting the overall safety of the vehicle.

[0003] The traditional method to solve manufacturing errors is to precisely control the physical precision of each component, using conventional methods such as the spacing of the positioning holes on the trolley, the positioning accuracy of the conveyor line, and the control of the diameter of the reference holes. The common drawback of these methods is that they are expensive and labor-intensive, and can only control the tolerance within a certain range. When encountering parts that exceed the tolerance, it is easy to cause production line downtime, resulting in serious waste of production capacity. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a vehicle body positioning measurement system to solve the technical problem in the prior art that production line shutdowns are caused by encountering out-of-tolerance parts, resulting in serious waste of production capacity; the purpose of the present invention is also to provide a method for vehicle body positioning measurement.

[0005] To achieve the above objectives, the vehicle body positioning and measurement system provided by this invention adopts the following technical solution:

[0006] A vehicle body positioning measurement system, comprising:

[0007] Four vision sensors are arranged around the vehicle body being tested to detect feature point information on the vehicle body.

[0008] The host computer is connected to the vision sensor to receive the feature point information and extract the feature contour information, and compares it with the pre-recorded zero-position reference information of the vehicle body to obtain the current position offset of the vehicle body being tested.

[0009] The industrial robot is connected to the host computer to obtain the position offset, so as to realize the automatic correction of the industrial robot's process trajectory.

[0010] Furthermore, each of the aforementioned vision sensors is used to align with the round holes, square holes, and waist holes on the vehicle body, and the feature point information includes the positional information of the round holes, square holes, and waist holes.

[0011] Furthermore, each of the vision sensors is also equipped with a supplementary light for illumination, so that the identified feature points can present clear black and white features, thereby facilitating the host computer to extract the contours of the feature point information.

[0012] Furthermore, each of the aforementioned visual sensors and adjacent supplementary lights are fixedly installed on the ground or mounted on a column.

[0013] The beneficial effects of the vehicle body positioning measurement system provided by this invention are:

[0014] 1) Body positioning measurement eliminates the need to manufacture mechanical positioning devices for new body models, significantly reducing the number of traditional positioning pins, fixtures, and other mechanical positioning equipment, thus reducing equipment processing costs; non-contact measurement and high cycle time enable multi-model co-production, improving the flexibility of the production line.

[0015] 2) By utilizing the detection performance of vision sensors, the action time of traditional mechanical positioning mechanisms can be reduced, and the measurement cycle can be faster; unnecessary equipment downtime caused by the addition of new models can be reduced, the flexibility of the production line can be improved, the production capacity can be expanded, and the investment costs of equipment for various models can be reduced.

[0016] Through the above settings, the present invention has completed the optimization and upgrading of the existing production line, effectively solving the technical problem in the prior art that the production line stops when encountering out-of-tolerance parts, resulting in serious waste of production capacity.

[0017] To achieve the above objectives, the vehicle body positioning measurement method provided by this invention adopts the following technical solution:

[0018] A method for vehicle body positioning measurement includes the following steps:

[0019] Using a laser tracker, the coordinate system of each vision sensor is established to obtain the positional relationship of the vision sensor relative to the reference coordinate system. Where C is the vision sensor, and i is the vision sensor number, i=1~4;

[0020] Using a reference vehicle body as the zero-point measurement, it is placed at the current process station, with supplementary lighting turned on and a vision sensor collecting feature point information on the vehicle body. The positional relationship between the reference vehicle body and the sensor is then measured. , where Z is the base vehicle body;

[0021] Using a laser tracker to measure the positional relationship of the industrial robot Base0 relative to the reference coordinate system. Where j = 1 to n, and n represents the number of industrial robots;

[0022] Vehicle body position measurement: After the vehicle body to be measured enters the workstation, the supplementary lighting is turned on, and the vision sensor collects feature point information on the vehicle body to obtain the relative position between the vision sensor and the current position of the vehicle body being measured. , where i is the visual sensor number;

[0023] The positional relationship of the vehicle body relative to the reference coordinate system as measured by the i-th visual sensor is: , i = 1~4;

[0024] Each vision sensor measures the positional relationship between the zero-position vehicle body and the industrial robot Base0: , where j=1~n, n represents the number of industrial robots, and i is the sequence number of the vision sensor, i=1~4;

[0025] Based on the vehicle body position measured by the i-th visual sensor, the positional relationship between the current measured vehicle body position and the reference coordinate system is obtained: ;

[0026] Each vision sensor measures the current positional relationship between the measured vehicle body and the industrial robot Base0: , where j=1~n, n represents the number of industrial robots, and i is the sequence number of the vision sensor, i=1~4;

[0027] Based on the position of the industrial robot, the current offset of the tested vehicle body relative to the reference zero-position vehicle body is: , where j = 1 ~ n, and n represents the number of industrial robots;

[0028] When measuring the vehicle body at the reference zero position, the industrial robot Base0 is determined as the user coordinate system. Where j = 1~n, n represents the number of industrial robots, and process trajectory points are established;

[0029] The measured offset of the vehicle body relative to the reference position is sent to the industrial robot j, which enables automatic correction of the industrial robot's trajectory.

[0030] The beneficial effects of the vehicle body positioning measurement method provided by this invention are:

[0031] 1) Body positioning measurement eliminates the need to manufacture mechanical positioning devices for new body models, significantly reducing the number of traditional positioning pins, fixtures, and other mechanical positioning equipment, thus reducing equipment processing costs; non-contact measurement and high cycle time enable multi-model co-production, improving the flexibility of the production line.

[0032] 2) By utilizing the detection performance of vision sensors, the action time of traditional mechanical positioning mechanisms can be reduced, and the measurement cycle can be faster; unnecessary equipment downtime caused by the addition of new models can be reduced, the flexibility of the production line can be improved, the production capacity can be expanded, and the investment costs of equipment for various models can be reduced.

[0033] Through the above settings, the present invention has completed the optimization and upgrading of the existing production line, effectively solving the technical problem in the prior art that the production line stops when encountering out-of-tolerance parts, resulting in serious waste of production capacity. Attached Figure Description

[0034] Figure 1 This is a usage diagram of the vehicle body positioning measurement system provided by the present invention;

[0035] Figure 2 This is a flowchart of the vehicle body positioning measurement method provided by the present invention.

[0036] The numbers in the diagram are: 1. Vision sensor; 2. Vehicle body under test; 3. Industrial robot; 4. Column. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0038] It should be noted that the main concept of this invention lies in reducing the action time of traditional mechanical positioning mechanisms by utilizing the detection performance of the vision sensor 1, thereby achieving non-contact measurement. This eliminates the need to manufacture mechanical positioning devices for new car bodies, significantly reducing the number of traditional positioning pins, fixtures, and other mechanical positioning equipment, reducing equipment processing costs, increasing the flexibility of the production line, and thus expanding production capacity while reducing equipment investment costs for various car models. The above concept will be further elaborated below with reference to specific embodiments.

[0039] Specific embodiments of the vehicle body positioning measurement system provided by this invention:

[0040] refer to Figure 1 , Figure 1 A usage status diagram for the vehicle body positioning measurement system is shown, from Figure 1 As can be seen from the diagram, the vehicle body positioning measurement system includes four vision sensors 1, which are arranged around the vehicle body to detect feature point information on the side of the vehicle body.

[0041] The feature point information mainly includes round holes, square holes, and waist holes on the vehicle body. Correspondingly, the four vision sensors 1 are also aligned with the round holes, square holes, and waist holes on the vehicle body when they are arranged.

[0042] The four vision sensors 1 are also connected to a host computer. The host computer has pre-recorded information on the zero-position reference position of the vehicle body. The host computer is used to receive feature point information, extract feature contours, and compare them with the zero-position reference position information to obtain the current position offset of the vehicle body 2 being measured.

[0043] The body processing mainly relies on process robots. Therefore, the entire system also includes process robots that are connected to the host computer. The process robots are used to obtain the position offset calculated by the host computer, and then realize the automatic correction of their own process trajectory, so as to meet the processing requirements of the tested body 2.

[0044] To facilitate the extraction of feature point information by the host computer, each vision sensor 1 is also equipped with a supplementary light for supplementary lighting, so that the identified feature point information presents a clear black and white feature, thereby facilitating the contour extraction of the feature point information by the host computer.

[0045] In this embodiment, each vision sensor 1 and its adjacent supplementary light are fixedly installed on the column 4, which is fixed to the side of the vehicle body 2 being tested. In other embodiments, each vision sensor 1 and its adjacent supplementary light can also be installed on the ground, as long as the vision sensor 1 can meet the detection requirements.

[0046] The working principle of the vehicle body positioning and measurement system provided by this invention is as follows: After the vehicle body 2 to be measured is transported to its position via a conveyor line or a conveyor trolley, four vision sensors 1 begin to detect the feature point information of the vehicle body. A supplementary light is used for supplementary lighting. The host computer extracts the contour information of the vehicle body based on the feature point information detected by the vision sensors 1 and compares it with the zero-position reference information of the vehicle body to obtain the current position offset of the vehicle body 2. The position offset is then sent to the industrial robot 3, which automatically corrects its own process trajectory, thereby better processing the vehicle body 2 to be measured.

[0047] Specific embodiments of the vehicle body positioning measurement method provided by this invention:

[0048] refer to Figure 2 , Figure 2 A flowchart of the vehicle body positioning measurement method provided by the present invention is shown, from which... Figure 2 As can be seen from this, the method for vehicle body positioning measurement includes the following steps:

[0049] S1: Use a laser tracker to establish a coordinate system for each vision sensor, obtaining the positional relationship of the vision sensor relative to the reference coordinate system. Where C is the vision sensor, and i is the vision sensor number, i=1~4;

[0050] S2: Using a reference vehicle body as the zero-point measurement, place it at the current process station, turn on the supplementary lighting, and use the vision sensor to collect feature point information on the vehicle body to measure the positional relationship between the reference vehicle body and the sensor. , where Z is the base vehicle body;

[0051] S3: Utilize a laser tracker to measure the positional relationship of the industrial robot Base0 relative to the reference coordinate system. Where j = 1 to n, and n represents the number of industrial robots;

[0052] S4: Vehicle Body Position Measurement: After the vehicle body to be measured enters the workstation, the supplementary lighting is turned on, and the vision sensor collects feature point information on the vehicle body to obtain the relative position between the vision sensor and the current position of the vehicle body being measured. , where i is the visual sensor number;

[0053] S5: The positional relationship between the zero-position vehicle body and the reference coordinate system measured by the i-th visual sensor is: , i = 1~4;

[0054] S6: Each vision sensor measures the positional relationship between the zero-position vehicle body and the industrial robot Base0: , where j=1~n, n represents the number of industrial robots, and i is the sequence number of the vision sensor, i=1~4;

[0055] S7: Based on the vehicle body position measured by the i-th visual sensor, obtain the positional relationship between the current measured vehicle body position and the reference coordinate system: ;

[0056] S8: Each vision sensor measures the current positional relationship between the measured vehicle body and the industrial robot Base0: , where j=1~n, n represents the number of industrial robots, and i is the sequence number of the vision sensor, i=1~4;

[0057] S9: Based on the position of the industrial robot, the current offset of the tested vehicle body relative to the reference zero-position vehicle body is: , where j = 1 ~ n, and n represents the number of industrial robots;

[0058] S10: When measuring the vehicle body reference zero position, determine the industrial robot Base0 as the user coordinate system. Where j = 1~n, n represents the number of industrial robots, and process trajectory points are established;

[0059] S11: The measured offset of the current vehicle body relative to the reference position is sent to the industrial robot j, which enables automatic correction of the industrial robot's trajectory.

[0060] The beneficial effects of the vehicle body positioning measurement method provided by this invention are:

[0061] 1) Body positioning measurement eliminates the need to manufacture mechanical positioning devices for new body models, significantly reducing the number of traditional positioning pins, fixtures, and other mechanical positioning equipment, thus reducing equipment processing costs; non-contact measurement and high cycle time enable multi-model co-production, improving the flexibility of the production line.

[0062] 2) By utilizing the detection performance of vision sensors, the action time of traditional mechanical positioning mechanisms can be reduced, and the measurement cycle can be faster; unnecessary equipment downtime caused by the addition of new models can be reduced, the flexibility of the production line can be improved, the production capacity can be expanded, and the investment costs of equipment for various models can be reduced.

[0063] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A measurement method for a vehicle body positioning measurement system, characterized in that, The measurement system includes: Four vision sensors are arranged around the vehicle body under test. Each vision sensor is fixedly installed on a pillar or the ground next to the vehicle body under test, in conjunction with an adjacent supplementary light. They are used to acquire feature point images and obtain feature point information on the vehicle body under supplementary lighting conditions. The feature points include round holes, square holes and oblong holes. A laser tracker is used to establish a coordinate system for each vision sensor to obtain the positional relationship of each vision sensor relative to a reference coordinate system, denoted as . And used to measure the positional relationship of the industrial robot Base0 participating in the work relative to the reference coordinate system. Where j = 1 to n, and n represents the number of industrial robots; The host computer is connected to the vision sensor and is used to receive the feature point information and extract the feature contour information. Based on the positional relationship of each vision sensor relative to the reference coordinate system and the positional relationship of the industrial robot Base0 relative to the reference coordinate system, and compared with the pre-recorded zero-position reference position information of the vehicle body, the current position offset of the tested vehicle body in the coordinate system of the industrial robot Base0 is obtained. The industrial robot is connected to the host computer to obtain the position offset, so as to realize the automatic correction of the industrial robot's process trajectory. The position offset is obtained as follows: Using a reference vehicle body as the zero-point measurement, it is placed at the current process station, with supplementary lighting turned on and a vision sensor collecting feature point information on the vehicle body. The positional relationship between the reference vehicle body and the sensor is then measured. , where Z is the reference vehicle body and i is the visual sensor number; After the vehicle body under test enters the workstation, the supplementary lighting is turned on, and the vision sensor collects feature point information on the vehicle body to obtain the relative position of the vision sensor and the current position of the vehicle body under test. , where i is the visual sensor number; The positional relationship of the vehicle body relative to the reference coordinate system as measured by the i-th visual sensor is: Each vision sensor measures the positional relationship between the zero-position vehicle body and the industrial robot Base0: , where j=1~n, n represents the number of industrial robots, and i is the sequence number of the vision sensor, i=1~4; Based on the vehicle body position measured by the i-th visual sensor, the positional relationship between the current measured vehicle body position and the reference coordinate system is obtained: Each vision sensor measures the current position of the vehicle body relative to the industrial robot's Base0 position. , where j=1~n, n represents the number of industrial robots, and i is the sequence number of the vision sensor, i=1~4; Based on the position of the industrial robot, the current offset of the tested vehicle body relative to the reference zero-position vehicle body is: , where j = 1 ~ n, and n represents the number of industrial robots; When measuring the vehicle body reference zero position, the industrial robot Base0 is determined as the user coordinate system Pj, where j=1~n, n represents the number of industrial robots, and process trajectory points are established; The measured offset of the vehicle body relative to the reference position is sent to the industrial robot j, which enables automatic correction of the industrial robot's trajectory.

2. The measurement method for a vehicle body positioning measurement system according to claim 1, characterized in that: Each of the aforementioned vision sensors is used to align with the round holes, square holes, and waist holes on the vehicle body, and the feature point information includes the position information of the round holes, square holes, and waist holes.

3. The measurement method for a vehicle body positioning measurement system according to claim 1 or 2, characterized in that: The supplementary light is used to enable the identified feature points to present a clear black and white appearance, thereby facilitating the host computer to extract the contour information of the feature points.

Images