3D radar scanning robot based on two-degree-of-freedom parallel mechanism motion platform

Abstract

The invention discloses a 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform, and relates to the technical field of granary measurement. The problem that in the information acquisition process of an existing mechanical 3D millimeter wave radar, due to the fact that a used three-degree-of-freedom series mechanism is large in motion error, the granary inventory detection precision is low is solved. A tray (4) and a base part (1) are arranged in parallel, the tray (4) and the base part (1) are connected through a movable part (2), the upper portion of the movable part (2) is rotationally connected with the tray (4), a control part (3) is installed between the tray (4) and the base part (1), the upper portion of the control part (3) adjusts the pose of the tray (4) in a telescopic mode, and a 3D millimeter wave radar (5) is installed on the tray (4). The method is used for the millimeter wave radar detector in the granary and related real-time measurement.

Description

Technical Field

[0001] The invention relates to the field of real-time measurement of granaries, and in particular to a 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform. Background Art

[0002] The laser radar scanning device has a 360° rotating pan-tilt, which can form a 270×360° point cloud coverage, and can obtain high-precision and high-precision three-dimensional point cloud data of the surrounding environment without light and GPS. Its usage scenario is the grain warehouse inventory detection system. The system is a system that automatically measures height, volume, quality and other information based on laser point cloud data, and displays a three-dimensional visual picture of the measured material to the user at the application end; at the same time, when the relevant information exceeds the set threshold, the system can automatically send an alarm message to the relevant management personnel and use AI algorithms such as integrated point cloud data collection, noise data removal, surface three-dimensional reconstruction, hole fitting repair, and stacking density prediction model to achieve rapid modeling and volume calculation of material pile shape, so as to accurately grasp the variety, quantity, quality, storage time, storage points and other conditions of the grain inventory of grain management enterprises, supervise and guide grain management enterprises to strengthen inventory management, find problems in time, plug loopholes, and eliminate risks.

[0003] The robotic arm used in the existing laser radar scanning device is a three-degree-of-freedom serial mechanism, which has large errors when used. The reason for the above technical problems is that the current robotic arm is not a simple mechanical feature, but a comprehensive device that couples electromechanical and hydraulic systems. The three-degree-of-freedom parallel mechanism achieves the effect of free movement of the front end of the robotic arm by controlling the movement of its three parts. There are systematic errors in the control of each part, and the individual errors of the previous part will accumulate in the next part. If there is no end position feedback, the error may cause the accuracy of the robotic arm to be completely unusable. In addition, the actual motion stability performance and high-precision following performance of the connected robotic arm under complex and variable working conditions are easily affected by manufacturing processes, assembly errors, external environmental interference, etc.

[0004] In summary, during the information collection process, the existing mechanical 3D millimeter-wave radar has a large motion error due to the three-degree-of-freedom series mechanism used, which leads to the problem of low grain warehouse inventory detection accuracy. Summary of the invention

[0005] The purpose of the present invention is to solve the problem of low grain storage detection accuracy caused by large motion errors in the three-degree-of-freedom series mechanism used in the existing mechanical 3D millimeter-wave radar during information collection. A 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform is provided.

[0006] The technical solution of the present invention is:

[0007] A 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform includes a 3D millimeter-wave radar, a base part, a control part, a movable part and a tray. The tray and the base part are arranged in parallel, the tray and the base part are connected by the movable part, and the upper part of the movable part is rotatably connected to the tray. The control part is installed between the tray and the base part, and the upper part of the control part adjusts the position of the tray by telescoping. The 3D millimeter-wave radar is installed on the tray.

[0008] Preferably, the base portion is a disc-shaped base.

[0009] Preferably, the control part is two retractable push rods.

[0010] Furthermore, two retractable push rods are respectively installed in the X-axis direction and the Y-axis direction of the pallet with the center of the pallet as the center.

[0011] Preferably, the retractable push rod is an electric push rod.

[0012] Furthermore, the movable part includes a support rod and a joint ball head, the lower end of the support rod is fixedly mounted on the upper end surface of the tray, the joint ball head is fixedly mounted on the upper end of the support rod, and the upper part of the joint ball head is movably embedded in the lower end of the tray.

[0013] Preferably, the tray is a disc-shaped tray, and the thickness of the base portion is smaller than the thickness of the tray.

[0014] Preferably, the tray and base portion are arranged coaxially.

[0015] Preferably, two push rod insertion holes and an inwardly concave arc-shaped hole are respectively provided at the lower part of the tray.

[0016] Preferably, the 3D millimeter wave radar is detachably mounted on the tray by bolts.

[0017] Compared with the prior art, the present invention has the following effects:

[0018] The present invention reduces the operation error by using a parallel mechanism with two degrees of freedom, and can better achieve the radar detection task of the granary. The present invention avoids the problem of large errors and high control difficulty caused by the movement of the radar detection device driven by multiple parts by replacing the original series mechanism with a parallel mechanism. In the process of controlling the length change of the push rod, the errors generated by the two push rods do not affect each other and will not be superimposed, which is easy to control.

[0019] In terms of warehousing, millimeter wave technology can be used for intelligent management and cargo tracking within the warehouse. Millimeter wave radar can be used to achieve high-precision positioning and tracking of goods, thereby improving warehouse management efficiency and cargo safety. It can also provide accurate and real-time 3D measurement images of materials, provide reliable data support for material entry and exit decisions, and avoid the impact of incorrect entry and exit volume on production. The solution can also monitor the status of materials and issue alarms for abnormal situations and handle them in a timely manner. This can maximize the volume utilization rate in the warehouse, reduce costs, and improve supply chain efficiency. With the help of this product, the accuracy of radar detection devices in detecting granaries is improved, thereby achieving refined measurement of granary volume and more accurate modeling, so that the entire granary inventory 3D system can play a better role. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Description of reference numerals:

[0022] 1. Base part, 2. Movable part, 3. Control part, 4. Tray, 5. 3D millimeter wave radar, 2-1. Support rod, 2-2. Joint ball head, 4-1. Push rod insertion hole, 4-2. Concave arc hole. DETAILED DESCRIPTION

[0023] Specific implementation method 1: Combination Figure 1 To illustrate this embodiment, this embodiment includes a 3D millimeter-wave radar 5, a base part 1, a control part 3, a movable part 2 and a tray 4. The tray 4 is arranged parallel to the base part 1. The tray 4 and the base part 1 are connected by the movable part 2, and the upper part of the movable part 2 is rotatably connected to the tray 4. The control part 3 is installed between the tray 4 and the base part 1, and the upper part of the control part 3 adjusts the posture of the tray 4 by telescoping. The 3D millimeter-wave radar 5 is installed on the tray 4.

[0024] The base part 1, the control part 3, the movable part 2 and the tray 4 of this embodiment together constitute a two-degree-of-freedom parallel mechanism. The 3D millimeter-wave radar 5 can be installed on the two-degree-of-freedom parallel mechanism. The movement of the two-degree-of-freedom parallel mechanism provides the posture required for data collection by the 3D millimeter-wave radar 5. The entire adjustment process has a simple structure and precise movement.

[0025] In this embodiment, if the center of the base part 1 is taken as the origin, a two-dimensional rectangular coordinate system is established on its circular surface, and the two push rods (referring to the control part 3) are respectively located at the intersection of the coordinate axis and the circle. The lower part of the push rod is fixed to the base, and the upper part is connected to the tray. In this way, by adjusting the length of the two push rods, the pitch and roll degrees of freedom of the upper tray can be controlled, thereby achieving control of the movement of the tray.

[0026] Specific implementation method 2: Combination Figure 1 The present embodiment will be described. The base portion 1 of the present embodiment is a disc-shaped base.

[0027] In this way, this part is a disc, which is the supporting part of the whole parallel mechanism. The top is connected to the rest of the whole mechanism, and the bottom is connected to the grain bin detection rod, which plays the role of fixing the whole device. The other components and implementation methods are the same as the specific implementation method 1.

[0028] The disc-shaped base in this embodiment is installed in the granary, and the installation method is mainly detachable. It is installed in a suitable position according to actual needs.

[0029] Specific implementation method three: Combination Figure 1 To explain this embodiment, the control part 3 of this embodiment is two retractable push rods. In this arrangement, the posture adjustment is achieved by different telescopic lengths of the push rods in the two-dimensional coordinate system. Other components and connection relationships are the same as those of the specific embodiment 1 or 2.

[0030] In order to ensure the accuracy of the movement of the entire laser radar scanning device during the data collection process, the push rod is preferably a controllable push rod, which can ensure the accuracy of posture control.

[0031] Specific implementation method four: Combination Figure 1 To describe this embodiment, the two retractable push rods of this embodiment are respectively installed in the X-axis direction and the Y-axis direction of the tray 4 with the center of the circle of the tray 4 as the center.

[0032] With this arrangement, two degrees of freedom can be achieved in the X-axis direction and the Y-axis direction, and the center is the circle, so the accuracy of posture adjustment can be guaranteed. The other components and connection relationships are the same as any one of the specific implementation methods one to three.

[0033] Specific implementation method five: Combination Figure 1 This embodiment is described. The retractable push rod of this embodiment is an electric push rod. This arrangement facilitates automatic control according to the designed program and the data range actually required to be collected, thereby reducing the labor intensity of the staff. The other components and connection relationships are the same as any one of the specific embodiments 1 to 4.

[0034] Specific implementation method six: Combination Figure 1 To illustrate this embodiment, the movable part 2 of this embodiment includes a support rod 2-1 and a joint ball head 2-2. The lower end of the support rod 2-1 is fixedly mounted on the upper end surface of the tray 4, the joint ball head 2-2 is fixedly mounted on the upper end of the support rod 2-1, and the upper part of the joint ball head 2-2 is movably embedded in the lower end of the tray 4.

[0035] In this way, this part is mainly composed of a joint ball head connected by a rod. The rod is located at the center of the base, connected to the base part at the bottom and connected to the tray part at the top. In this way, the upper tray part can move freely. The other components and connection relationships are the same as any one of the specific implementation methods 1 to 5.

[0036] The support rod 2 - 1 of this embodiment is a columnar rod, and the diameter of the support rod 2 - 1 is larger than the diameter of the electric push rod, so as to increase the service life.

[0037] Specific implementation method seven: Combination Figure 1 The present embodiment will be described. The tray 4 of the present embodiment is a disc-shaped tray, and the thickness of the base portion 1 is smaller than the thickness of the tray 4 .

[0038] In this configuration, this part is a disc like the base, responsible for carrying the radar detection device. Through the control of the parts below, it realizes its own movement and drives the radar detection device to move in all directions in space. The other components and connection relationships are the same as any one of the specific implementation methods one to six.

[0039] Specific implementation method eight: Combination Figure 1 To explain this embodiment, the tray 4 and the base part 1 of this embodiment are arranged coaxially. This arrangement facilitates posture adjustment. Other components and connection relationships are the same as any one of the specific embodiments 1 to 7.

[0040] Specific implementation method nine: Combination Figure 1 To explain this embodiment, the lower part of the tray 4 of this embodiment is provided with two push rod insertion holes 4-1 and a concave arc-shaped hole 4-2. Such arrangement facilitates connection with the control part 3 and the movable part 2. Other components and connection relationships are the same as any one of the specific embodiments 1 to 8.

[0041] Specific implementation method ten: Combination Figure 1 To describe the present embodiment, the 3D millimeter wave radar 5 of the present embodiment is detachably mounted on the tray 4 by bolts.

[0042] With such arrangement, the connection mode is simple and reliable. Other components and connection relationships are the same as any one of the specific implementation modes 1 to 9.

[0043] The error of the millimeter-wave radar carried by the two-degree-of-freedom platform only comes from two push rods. The present invention replaces the three-degree-of-freedom series robot arm with a two-degree-of-freedom parallel mechanism, which is relatively smaller in size and reduces the unnecessary movement of the millimeter-wave radar in space, thereby reducing the difficulty of modeling and increasing accuracy while reducing the space it may need to occupy. The two-degree-of-freedom parallel mechanism also has the advantages of good dynamic performance, small motion inertia, strong load capacity, and high rigidity, which are helpful for improving scanning accuracy. In the present invention, the two push rods are independent of each other, and the resulting system error is only reflected in one degree of freedom, avoiding the problem of error accumulation. And through the precise control of the two push rods, the millimeter-wave radar can detect at all angles with high scanning accuracy.

[0044] Combination Figure 1 The working principle of the present invention is described:

[0045] The main components of the two-degree-of-freedom parallel system are a servo motor (outside the system of the present invention), an active arm, a driven arm (push rod 3), and in addition there are a balance rod (2) and a tray (1, 4). The main components of the control system are a push rod, a controller, a servo driver and a servo motor. The static platform can always remain in a fixed state with the frame through the manipulator control system. When the translation disk on the plane is in a moving state, the servo motor (connected to the starting end of the active arm) starts to drive the two push rods to complete the joint operation process of the millimeter wave radar movement. The target motion trajectory curve of the millimeter wave radar needs to be pre-planned in the imaginary axis (x, y) (actual space), and the interpolation instructions including straight lines, arcs, polynomials, etc. are used in the imaginary axis to complete the determination of the target motion trajectory curve. The coordinates (x, y) of the current tray 4 in the imaginary axis (the output of the interpolation instruction at each moment) are used as the input of the kinematic inverse algorithm. The two servo motor angles are the real axis coordinates of the corresponding millimeter wave radar. The real axis coordinates at this time can be obtained through related operations. The two angles are transmitted to the two motors of the push rod in real time, and the motors complete synchronous coordinated operation accordingly, thereby realizing effective control of the millimeter wave radar motion process. In this way, it is possible to scan the granary uninterruptedly within the required angle range, and at the same time establish a three-dimensional model of the granary, and automatically calculate information such as height, volume, and mass.

[0046] In addition, the two-degree-of-freedom parallel mechanism of the present invention is equipped with a millimeter-wave radar on the tray, while the comparative invention is equipped with a driving assembly; the center of the tray of the present invention is supported by a combination of a rod and a joint ball head, and the connecting lines of the two push rods and the movable part on the tray are perpendicular to each other. In the comparative invention, the first base, the second base and the support rod are arranged in a triangular shape on the lower platform; the push rod of the present invention does not require auxiliary connections such as connecting shafts.

[0047] The present invention focuses on utilizing the positioning accuracy of a two-degree-of-freedom parallel mechanism and is used for detecting a granary with a millimeter-wave radar.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform, characterized in that: It includes a 3D millimeter wave radar (5), a base part (1), a control part (3), a movable part (2) and a tray (4). The tray (4) and the base part (1) are arranged in parallel, the tray (4) and the base part (1) are connected via a movable part (2), and the upper part of the movable part (2) is rotatably connected to the tray (4), the control part (3) is installed between the tray (4) and the base part (1), and the upper part of the control part (3) adjusts the position of the tray (4) by telescoping, and the 3D millimeter wave radar (5) is installed on the tray (4).

2. A 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 1, characterized in that: The base part (1) is a disc-shaped base.

3. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 2, characterized in that: The control part (3) is two retractable push rods.

4. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 3, characterized in that: The two retractable push rods are respectively installed in the X-axis direction and the Y-axis direction of the tray (4) with the center of the tray (4) as the center.

5. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 4, characterized in that: The retractable push rod is an electric push rod.

6. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 5, characterized in that: The movable part (2) comprises a support rod (2-1) and a joint ball head (2-2); the lower end of the support rod (2-1) is fixedly mounted on the upper end surface of the tray (4); the joint ball head (2-2) is fixedly mounted on the upper end of the support rod (2-1); and the upper part of the joint ball head (2-2) is movably embedded in the lower end of the tray (4).

7. A 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 1 or 6, characterized in that: The tray (4) is a disc-shaped tray, and the thickness of the base portion (1) is smaller than the thickness of the tray (4).

8. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 7, characterized in that: The tray (4) and the base portion (1) are coaxially arranged.

9. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 8, characterized in that: The lower part of the tray (4) is respectively provided with two push rod insertion holes (4-1) and an inwardly concave arc-shaped hole (4-2).

10. The 3D radar scanning robot based on a two-degree-of-freedom parallel mechanism motion platform according to claim 1, characterized in that: The 3D millimeter wave radar (5) is detachably mounted on the tray (4) by means of bolts.

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