Secondary positioning device and positioning method for a hybrid mobile robot

Abstract

The application discloses a secondary positioning device and method of a composite mobile robot, which comprises a mobile robot, a buffer assembly, a sensor, a mechanical arm assembly, a limiting frame, a limiting assembly and a brake; through cooperation of the sensor and the buffer assembly, the sensor can accurately perceive the position of the mobile robot in the limiting frame, and the sensor is a cylindrical sensor, so that the sensing accuracy is higher; therefore, the station task can be completed in the upper computer, the relative positions of the mobile robot when entering other different stations are fixed, a 2D industrial camera is not needed, the load of the mechanical arm is reduced, a supplementary light is not needed to be additionally arranged at each station to ensure normal shooting of the camera, the overall cost is lower, camera identification two-dimensional code processing and mechanical arm end coordinate system calculation are not needed to be additionally performed, the overall processing process is more convenient, and the operation process is simpler.

Description

Technical Field

[0001] This invention relates to the field of robot processing technology, and in particular to a secondary positioning device and positioning method for a composite mobile robot. Background Technology

[0002] A robotic arm is a complex system characterized by high precision, multiple inputs and multiple outputs, high nonlinearity, and strong coupling. Due to its unique operational flexibility, it has been widely used in industrial assembly, safety and explosion-proof fields, and other areas. As a complex system, a robotic arm exhibits uncertainties such as parameter perturbations, external interference, and unmodeled dynamics. Therefore, the modeling of a robotic arm also contains uncertainties. For different tasks, it is necessary to plan the motion trajectory of the robotic arm's joints to cascade and form the end-effector pose. Robotic arms play a crucial role in automated processing. Since existing robotic arms cannot move independently, they need to be used in conjunction with mobile robots. These composite robots must maintain sufficiently high precision during movement to ensure the smooth operation of the processing.

[0003] Existing robotic arms use LiDAR navigation for positioning of composite mobile robots during processing. This positioning method has a accuracy of only ±(5-10) mm. Furthermore, to ensure normal operation, a 2D camera is typically installed at the end effector of the robotic arm. When moving to a pre-stop station, the robotic arm takes a picture of the station in a fixed posture, which is then uploaded to the robotic arm to determine the relative position of the clamp on the end effector flange to the station before proceeding with the operation. This process is not only costly but also causes the robotic arm to exceed its weight capacity during operation. In complex lighting environments, additional supplementary lighting is required at each station to ensure proper camera operation. A QR code beacon also needs to be added to each station, and the relative position of the QR code to the parts on the station needs to be calibrated. Additionally, an industrial control computer is required to process the 2D industrial camera's recognition of the QR code and perform coordinate transformation calculations with the robotic arm's end effector, further increasing processing costs and making the process and operation more cumbersome. Therefore, it is necessary to research a new technical solution to address these problems. Summary of the Invention

[0004] In view of this, the present invention addresses the deficiencies of the existing technology, and its main objective is to provide a secondary positioning device and positioning method for a composite mobile robot, which can effectively solve the problems of low positioning accuracy, high processing cost, and more complex processing and operation of existing composite robot positioning methods.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A secondary positioning device for a composite mobile robot includes a mobile robot, a buffer assembly, a sensor, a robotic arm assembly, a limiting frame, a limiting component, and a brake. The mobile robot can move back and forth between external machining centers. The buffer assembly is located on the side of the mobile robot and moves back and forth with it. The sensor is located at the outer end of the buffer assembly and moves back and forth at the front end of the mobile robot, and the sensor is cylindrical. The robotic arm assembly is mounted on the mobile robot and moves back and forth with it. The limiting frame is located beside the external machining center and has a limiting groove with one open end, which cooperates with the mobile robot. The limiting component is movably mounted on the limiting frame and located in the limiting groove, and its position corresponds to that of the buffer assembly. The brake is mounted on the limiting frame and drives the limiting component to move back and forth.

[0006] As a preferred embodiment, the mobile robot is symmetrically provided with guide wheels on its left and right sides, and correspondingly, the inner wall of the limiting groove is provided with a guide groove that cooperates with the guide wheels.

[0007] As a preferred embodiment, the buffer assembly includes a first guide post, a contact plate, and a first spring; there are four first guide posts arranged at intervals, and the first guide posts are movably disposed at the front end of the mobile robot; the contact plate is fixed to the outer ends of the four first guide posts respectively and moves back and forth with the first guide posts; there are also four first springs, each first spring is sleeved on the corresponding first guide post, and the two ends of the first spring abut against the inner side wall of the contact plate and the outer side wall of the mobile robot respectively.

[0008] As a preferred embodiment, the sensor is disposed on the contact plate, and one end of the sensor extends out of the inner wall of the contact plate.

[0009] As a preferred embodiment, the robotic arm assembly includes a power distribution box, a hopper, a mounting base, and a robotic arm; the power distribution box is fixedly mounted on the mobile robot, and the upper surface of the power distribution box has a worktable, and the aforementioned mobile robot is electrically connected to the power distribution box; the hopper is disposed on the worktable; the mounting base is disposed on the worktable and located beside the hopper; the robotic arm is disposed on the mounting base and is electrically connected to the power distribution box.

[0010] As a preferred embodiment, the left and right side walls of the opening of the limiting frame are bent outward to form guide plates.

[0011] As a preferred embodiment, the limiting assembly includes a lead screw, a fixed plate, a second guide post, a crash barrier, and a second spring. The lead screw is rotatably mounted in the limiting frame and extends inward into the limiting groove. The fixed plate is fixedly mounted on the outer wall of the limiting frame. The aforementioned brake is mounted on the fixed plate and drives the lead screw to rotate back and forth. The second guide post is mounted on the limiting frame and located in the limiting groove. There are multiple second guide posts arranged at intervals, all located beside the lead screw. The crash barrier is mounted on the lead screw and engages with the outer end of the lead screw. The crash barrier is movably mounted on the second guide post. There are also multiple second springs, which are sleeved on the corresponding second guide posts. The two ends of the second springs abut against the side wall of the crash barrier and the inner wall of the limiting groove, respectively.

[0012] As a preferred embodiment, the outer end of the second guide post extends outward to form an anti-collision plate, and the outer end of the second guide post is fitted with an anti-collision rubber head.

[0013] As a preferred embodiment, a dispensing rack is also included, which is disposed on the side of the limiting frame.

[0014] A secondary localization method for a composite mobile robot, comprising the aforementioned secondary localization device for the composite mobile robot, includes the following steps: (1) Set three stations A, B and C in the limit frame of the host computer, and send a movement command to the mobile robot from point A to point C and back to point A. Point A is the track entry point, point B is the pre-stop point, and point C is the target station. (2) After the mobile robot reaches A, it begins to enter the limiting slot until the buffer component contacts the limiting component, and the mobile robot continues to move forward, thereby compressing the buffer component. The sensor will move towards the mobile robot along with the buffer component. (3) When point B is reached, the sensor just detects the outer shell of the mobile robot. At this time, the sensor detects the position of the mobile robot and the mobile robot stops moving. (4) The robotic arm assembly performs operations according to the set program; (5) After the robotic arm assembly completes the task, the brake is activated, and the brake drives the limit assembly to move forward. At this time, the sensor on the buffer assembly leaves the surface of the mobile robot, causing the sensing signal to be lost, so that the mobile robot continues to move towards point C. (6) After the mobile robot reaches point C, it returns to point A to complete the station task and then goes to the next work station to perform the work at the next work station.

[0015] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution: By incorporating a mobile robot, buffer components, sensors, robotic arm components, limit frames, limit components, and brakes, the system allows the sensors, in conjunction with the buffer components, to accurately perceive the position of the mobile robot within the limit frames. The cylindrical sensors provide higher sensing accuracy, enabling station tasks to be completed via a host computer. This ensures that the relative position of the mobile robot remains fixed when it enters different workstations. The cylindrical sensors have a sensing accuracy of approximately ±0.1mm, resulting in a mobile robot movement accuracy of approximately ±0.25mm, leading to more accurate overall positioning. Furthermore, the system eliminates the need for 2D industrial cameras, reducing the load on the robotic arm and eliminating the need for additional supplementary lighting at each workstation to ensure proper camera operation, thus lowering overall costs. It also eliminates the need for additional equipment for camera-based QR code recognition and robotic arm end-effector coordinate system calculations, making the entire processing process more convenient and the operation simpler.

[0016] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural schematic diagram of a preferred embodiment of the present invention; Figure 2 This is a partial lease diagram of a preferred embodiment of the present invention; Figure 3 yes Figure 2 Enlarged diagram of point A in the middle.

[0018] Explanation of reference numerals in the attached diagram: 10. Mobile robot 11. Guide wheel 20. Buffer assembly; 21. First guide post 22. Contact plate 23. First spring 30. Sensors; 40. Robotic arm components 41. Distribution box 42. Material silo 43. Mounting base 44. Robotic arm 45. Workbench; 50. Limit frame 501, Limiting groove; 502, Guide groove 51. Guide plate; 60. Limiting assembly 61. Lead screw; 62. Fixing plate 63. Second guide post; 64. Anti-collision plate 65. Second spring 66. Anti-collision rubber head 70. Brake; 80. Feeding rack. Detailed Implementation

[0019] Please refer to Figures 1 to 3As shown, it illustrates the specific structure of a preferred embodiment of the present invention, which includes a mobile robot 10, a buffer assembly 20, a sensor 30, a robotic arm assembly 40, a limiting frame 50, a limiting assembly 60, and a brake 70.

[0020] The mobile robot 10 can move back and forth between external processing centers; in this embodiment, guide wheels 11 are symmetrically arranged on the left and right sides of the mobile robot 10.

[0021] The buffer assembly 20 is disposed on the side of the mobile robot 10 and moves back and forth with the mobile robot 10. In this embodiment, the buffer assembly 20 includes a first guide post 21, a contact plate 22, and a first spring 23. There are four first guide posts 21 arranged at intervals, and the first guide posts 21 are movably disposed at the front end of the mobile robot 10. The contact plate 22 is fixed to the outer ends of the four first guide posts 21 and moves back and forth with the first guide posts 21. There are also four first springs 23, and each first spring 23 is sleeved on the corresponding first guide post 21. The two ends of the first spring 23 abut against the inner side wall of the contact plate 22 and the outer side wall of the mobile robot 10, respectively. The first spring 23 is used to cause the contact plate 22 to reset.

[0022] The sensor 30 is disposed at the outer end of the buffer assembly 20 and moves back and forth with the buffer assembly 20 at the front end of the mobile robot 10. The sensor 30 is a cylindrical sensor, which has higher sensing accuracy, around ±0.1mm, so that the accuracy of the mobile robot 10 during movement can reach around ±0.25mm. In this embodiment, the sensor 30 is disposed on the contact plate 22, and one end of the sensor 30 extends out of the inner sidewall of the contact plate 22.

[0023] The robotic arm assembly 40 is mounted on the mobile robot 10 and moves back and forth with the mobile robot 10. In this embodiment, the robotic arm assembly 40 includes a power distribution box 41, a hopper 42, a mounting base 43, and a robotic arm 44. The power distribution box 41 is fixedly mounted on the mobile robot 10, and a worktable 45 is provided on the upper surface of the power distribution box 41. The mobile robot 10 is electrically connected to the power distribution box 41. The hopper 42 is disposed on the worktable 45. The mounting base 43 is disposed on the worktable 45 and located beside the hopper 42. The robotic arm 44 is disposed on the mounting base 43 and electrically connected to the power distribution box 41. The robotic arm 44 is used to complete the operation process of the machining center according to the set degree.

[0024] The limiting frame 50 is located on the side of the external machining center. The limiting frame 50 has a limiting groove 501 with one end open, which cooperates with the mobile robot 10. In this embodiment, the inner wall of the limiting groove 501 is provided with a guide groove 502 that cooperates with the guide wheel 11. The aforementioned mobile robot 10 moves back and forth along the guide groove 502 through the cooperation of the guide wheel 11 and the guide groove 502. The left and right side walls at the opening of the limiting frame 50 are respectively bent outward to form guide plates 51, which are used to facilitate the mobile robot 10 to enter the limiting groove 501.

[0025] The limiting component 60 is movably mounted on the limiting frame 50 and located in the limiting groove 501, with the limiting component 60 corresponding to the position of the buffer component 20. In this embodiment, the limiting component 60 includes a lead screw 61, a fixing plate 62, a second guide post 63, a crash plate 64, and a second spring 65. The lead screw 61 is rotatably mounted in the limiting frame 50 and extends inward into the limiting groove 501. The fixing plate 62 is fixedly mounted on the outer wall of the limiting frame 50. The aforementioned brake 70 is mounted on the fixing plate 62 and drives the lead screw 61 to rotate back and forth. The second guide post 63 is mounted on the limiting frame 50 and located in the limiting groove 501. Multiple second guide posts 63 are arranged at intervals, each with a specific configuration. Beside the lead screw 61, a crash plate 64 is mounted on the lead screw 61 and engages with the outer end of the lead screw 61. The crash plate 64 is movably mounted on the second guide post 63. Multiple second springs 65 are also mounted on the corresponding second guide posts 63. The two ends of the second springs 65 abut against the side wall of the crash plate 64 and the inner wall of the limiting groove 501, respectively. The second springs 65 serve as a buffer to prevent the limiting component 60 from contacting the buffer component 20 and generating large stress, thereby causing damage to the components. The outer end of the second guide post 63 extends outward from the crash plate 64, and the outer end of the second guide post 63 is fitted with a crash head 66, which further enhances the protective effect.

[0026] The brake 70 is mounted on the limit frame 50 and drives the limit assembly 60 to move back and forth.

[0027] Furthermore, it also includes a material rack 80, which is located on the side of the limiting frame 50. The material rack 80 is used to store tools for use by the robotic arm assembly 40 when it is working.

[0028] The usage method of this embodiment is described in detail below: (1) Set three stations A, B and C in the limit frame 50 in the host computer, and send a movement command to the mobile robot 10 from point A to point C and back to point A. Point A is the track entry point, point B is the pre-stop point, and point C is the target station. (2) After the mobile robot 10 reaches A, it begins to enter the limiting groove 501 until the buffer component 20 contacts the limiting component 60, and the mobile robot 10 continues to move forward, thereby compressing the buffer component 20. The sensor 30 will move towards the mobile robot 10 along with the buffer component 20. (3) When point B is reached, the sensor 30 just detects the outer shell of the mobile robot 10. At this time, the sensor 30 detects the position of the mobile robot 10, and the mobile robot 10 stops moving. (4) The robotic arm assembly 40 performs operations according to the set program; (5) After the robotic arm assembly 40 completes the operation, the brake 70 is activated. The brake 70 drives the limit assembly 60 to move forward. At this time, the sensor 30 on the buffer assembly 20 leaves the surface of the mobile robot 10, causing the sensing signal to be lost, so that the mobile robot 10 continues to move towards point C. (6) After the mobile robot 10 reaches point C, it returns to point A to complete the station task and then goes to the next work station to perform the work at the next work station.

[0029] The key design feature of this invention is that by incorporating a mobile robot, a buffer assembly, a sensor, a robotic arm assembly, a limiting frame, a limiting component, and a brake, the sensor, in conjunction with the buffer assembly, can accurately perceive the position of the mobile robot within the limiting frame. Furthermore, the cylindrical sensor provides higher sensing accuracy, allowing station tasks to be completed via a host computer. This ensures that the relative position of the mobile robot remains fixed when entering different workstations. The cylindrical sensor has a sensing accuracy of approximately ±0.1mm, resulting in a mobile robot movement accuracy of approximately ±0.25mm, leading to more accurate overall positioning. Simultaneously, the invention eliminates the need for a 2D industrial camera, reducing the load on the robotic arm and eliminating the need for additional supplementary lighting at each workstation to ensure proper camera operation, thus lowering overall costs. It also eliminates the need for additional equipment for camera-based QR code recognition and robotic arm end-effector coordinate system calculations, making the overall processing more convenient and the operation simpler.

[0030] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A secondary positioning device for a composite mobile robot, characterized in that: The system includes a mobile robot, a buffer assembly, a sensor, a robotic arm assembly, a limit frame, a limit assembly, and a brake. The mobile robot can move back and forth between external machining centers. The buffer assembly is located on the side of the mobile robot and moves back and forth with it. The sensor is located at the outer end of the buffer assembly and moves back and forth at the front end of the mobile robot, and the sensor is cylindrical. The robotic arm assembly is mounted on the mobile robot and moves back and forth with it. The limit frame is located beside the external machining center and has a limit groove with one open end, which cooperates with the mobile robot. The limit assembly is movably mounted on the limit frame and located in the limit groove, and its position corresponds to that of the buffer assembly. The brake is mounted on the limit frame and drives the limit assembly to move back and forth. The limiting assembly includes a lead screw, a fixed plate, a second guide post, a crash plate, and a second spring. The lead screw is rotatably mounted in the limiting frame and extends inward into the limiting groove. The fixed plate is fixedly installed on the outer wall of the limiting frame. The aforementioned brake is mounted on the fixed plate and drives the lead screw to rotate back and forth. The second guide post is mounted on the limiting frame and located in the limiting groove. There are multiple second guide posts arranged at intervals, all located beside the lead screw. The crash plate is mounted on the lead screw and cooperates with the outer end of the lead screw. The crash plate is movably mounted on the second guide post. There are also multiple second springs, which are sleeved on the corresponding second guide posts. The two ends of the second springs abut against the side wall of the crash plate and the inner wall of the limiting groove, respectively.

2. The secondary positioning device for the composite mobile robot according to claim 1, characterized in that: The mobile robot is symmetrically equipped with guide wheels on its left and right sides, and correspondingly, the inner wall of the limiting groove is provided with a guide groove that cooperates with the guide wheels.

3. The secondary positioning device for the composite mobile robot according to claim 1, characterized in that: The buffer assembly includes a first guide post, a contact plate, and a first spring. There are four first guide posts arranged at intervals, and the first guide posts are movably disposed at the front end of the mobile robot. The contact plate is fixed to the outer ends of the four first guide posts and moves back and forth with the first guide posts. There are also four first springs, each of which is sleeved on the corresponding first guide post, and the two ends of the first spring abut against the inner side wall of the contact plate and the outer side wall of the mobile robot, respectively.

4. The secondary positioning device for the composite mobile robot according to claim 3, characterized in that: The sensor is mounted on the contact plate, with one end of the sensor extending out of the inner wall of the contact plate.

5. The secondary positioning device for the composite mobile robot according to claim 1, characterized in that: The robotic arm assembly includes a power distribution box, a hopper, a mounting base, and a robotic arm. The power distribution box is fixedly mounted on the mobile robot, and a worktable is provided on the upper surface of the power distribution box. The mobile robot is electrically connected to the power distribution box. The hopper is placed on the worktable. The mounting base is placed on the worktable and located next to the hopper. The robotic arm is placed on the mounting base and electrically connected to the power distribution box.

6. The secondary positioning device for the composite mobile robot according to claim 1, characterized in that: The left and right side walls of the opening of the limiting frame are bent outward to form guide plates.

7. The secondary positioning device for the composite mobile robot according to claim 1, characterized in that: The outer end of the second guide post extends outward to form a crash plate, and the outer end of the second guide post is fitted with a crash-resistant rubber head.

8. The secondary positioning device for the composite mobile robot according to claim 1, characterized in that: It also includes a dispensing rack, which is located next to the limit frame.

9. A secondary positioning method for a composite mobile robot, comprising the secondary positioning device for a composite mobile robot as described in any one of claims 1-8, characterized in that: It includes the following steps: (1) Set three stations A, B and C in the limit frame of the host computer, and send a movement command to the mobile robot from point A to point C and back to point A. Point A is the track entry point, point B is the pre-stop point, and point C is the target station. (2) After the mobile robot reaches A, it begins to enter the limiting slot until the buffer component contacts the limiting component, and the mobile robot continues to move forward, thereby compressing the buffer component. The sensor will move towards the mobile robot along with the buffer component. (3) When point B is reached, the sensor just detects the outer shell of the mobile robot. At this time, the sensor detects the position of the mobile robot and the mobile robot stops moving. (4) The robotic arm assembly performs operations according to the set program; (5) After the robotic arm assembly completes the task, the brake is activated, and the brake drives the limit assembly to move forward. At this time, the sensor on the buffer assembly leaves the surface of the mobile robot, causing the sensing signal to be lost, so that the mobile robot continues to move towards point C. (6) After the mobile robot reaches point C, it returns to point A to complete the station task and then goes to the next work station to perform the work at the next work station.

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