Radar positioning device and courtyard robot

Abstract

The invention discloses a radar positioning device and a courtyard robot, and the device comprises a two-dimensional laser radar which can carry out the distance measurement of a target object in each direction in a preset scanning plane with one point as an original point, and obtains the corresponding distance data; and the external rotation driving mechanism is used for driving the two-dimensional laser radar to rotate around an external rotation axis, and the external rotation axis is arranged at a non-parallel and non-vertical angle relative to the scanning plane. Through combination of the two-dimensional laser radar and the obliquely rotating external rotation driving mechanism, three-dimensional point cloud data acquisition is realized, and the problem that cost and precision cannot be obtained at the same time in a traditional scheme is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of robot positioning, and in particular relates to a radar positioning device and a garden robot. Background Art

[0002] With the rapid growth of demand for smart homes and garden automation, garden robots are gradually replacing traditional manual operations. In typical application scenarios such as mowing, security, and cleaning, accurate and reliable positioning technology is the core foundation for ensuring the autonomous operation of robots, that is, robots need to know their own location in order to plan and complete corresponding tasks. The current mainstream positioning solutions generally have the problem of difficult balance between cost, accuracy, and environmental adaptability: traditional buried wire solutions can only achieve boundary definition but cannot obtain accurate posture; GPS positioning is free of wiring but the accuracy is only at the meter level; RTK technology can achieve centimeter-level accuracy but relies on base station deployment and is easily affected by buildings and trees; pure vision solutions are sensitive to changes in lighting and have high algorithm complexity; RTK and vision fusion solutions improve stability but significantly increase hardware costs; and high-precision lidar solutions are difficult to popularize due to the cost of equipment at the 10,000-yuan level. Summary of the invention

[0003] The purpose of the present invention is to provide a robot positioning device to address the deficiencies of the prior art, so as to achieve the purpose of high positioning accuracy and low cost.

[0004] The present invention provides a radar positioning device, comprising:

[0005] A two-dimensional laser radar can measure the distance of a target in each direction within a predetermined scanning plane with one point as the origin, and obtain the corresponding distance data;

[0006] The external rotation drive mechanism is used to drive the two-dimensional laser radar to rotate around an external rotation axis, wherein the external rotation axis is set at a non-parallel and non-vertical angle relative to the scanning plane.

[0007] Optionally, the outward rotation driving mechanism comprises:

[0008] A rotating base, comprising a rotating body and a connecting plate, wherein the rotating body is connected to the two-dimensional laser radar, the connecting plate is connected to one end of the rotating body and extends an extension portion to the periphery, the extension portion is provided with at least one through hole for a bolt to pass through, wherein the bolt passes through the through hole and can be screwed to the two-dimensional laser radar to achieve connection between the connecting plate and the two-dimensional laser radar;

[0009] The driving assembly is used to drive the rotating body to rotate around the outer rotation axis.

[0010] Optionally, the driving assembly includes a motor structure, a driving wheel, a driven wheel and an annular transmission belt, the motor structure is used to drive the driving wheel to rotate, the annular transmission belt is wrapped around the outer circumference of the driving wheel and the driven wheel, the driving wheel drives the driven wheel to rotate synchronously through the annular transmission belt, and the driven wheel is connected to the rotating body.

[0011] Optionally, the rotating body is cylindrical, and the central axis of the rotating body coincides with the external rotation axis.

[0012] Optionally, the radar positioning device further includes a rotary encoder, and the rotary encoder is used to determine the rotation angle of the rotating body.

[0013] Optionally, the rotary encoder includes a code disk, at least one group of photoelectric sensors and a signal processing unit. The code disk is connected to the rotating body. A plurality of code ports arranged at intervals are provided on the outer circumference of the code disk. The photoelectric sensor includes at least one pair of light emitters and light receivers, which are symmetrically arranged on both sides of the code disk so that the code ports turn on or off the light path when rotating to generate corresponding pulse signals. The signal processing unit is connected to the photoelectric sensor and is used to calculate the rotation angle based on the number of pulses.

[0014] Optionally, a line passing through the origin and perpendicular to the scanning plane is a radar central axis;

[0015] The outer rotation axis intersects the radar central axis.

[0016] Optionally, the radar positioning device further includes a mounting base;

[0017] The outward rotation driving mechanism is installed on the installation base.

[0018] Optionally, the external rotation drive mechanism drives the two-dimensional laser radar to rotate within a preset rotation speed range and generates disturbances during the rotation process.

[0019] The present invention also provides a garden robot, comprising the radar positioning device as described above.

[0020] Based on the present invention, by combining a two-dimensional laser radar with a tilt-rotating external rotation drive mechanism, the present invention realizes the collection of three-dimensional point cloud data. Compared with traditional 3D laser radars, the present invention achieves the same positioning accuracy in low-speed scenarios through the combination of low-cost 2D radars and mechanical structure innovations. Specifically, the rotational motion of the two-dimensional laser radar and the tilt angle work together to solve the three-dimensional coordinates of each ranging point in a fixed coordinate system, solving the problem that cost and accuracy cannot be achieved at the same time in traditional solutions.

[0021] In addition to the aforementioned technical effects, the present invention also has the following outstanding technical effects:

[0022] (1) The rotating base includes a rotating body and a connecting plate, wherein an extension portion is extended from the outer periphery of the connecting plate, and the extension portion is provided with a plurality of through holes for bolts to pass through. Therefore, during the assembly process, the connection between the connecting plate and the two-dimensional laser radar can be completed by passing the bolts through the through holes and realizing screw connection with the two-dimensional laser radar. This assembly method significantly reduces the difficulty of assembly, and the structural design increases the connection area, which makes it possible to use a larger size in the structural size selection of the bolts, thereby ensuring the stability between the two-dimensional laser radar and the rotating base;

[0023] (2) Adding a disturbance strategy can change the scanning speed of the two-dimensional lidar, avoiding data overlap and omission, and ensuring that the three-dimensional point cloud data at each location has sufficient data volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 is a stereogram of a radar positioning device provided by an embodiment of the present invention;

[0026] Figure 2 is a stereoscopic diagram of the radar positioning device provided by an embodiment of the present invention from another viewing angle;

[0027] Figure 3 is a side view of a radar positioning device provided by an embodiment of the present invention;

[0028] Figure 4 It is a three-dimensional diagram of a rotating base provided by an embodiment of the present invention.

[0029] Description of Figure Numbers:

[0030] Label name Label name 100 2D LiDAR 200 External rotation drive mechanism 210 Rotating base 211 Rotating body 212 Connecting plate 2121 Extension 220 Drive components 221 Motor structure 222 Driving wheel 223 Driven wheel 224 Endless conveyor belt 300 Rotary encoders 310 Code disc 320 Photoelectric Sensors 400 Mounting Base DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] like Figures 1 to 3 As shown, an embodiment of the present invention provides a radar positioning device, including a two-dimensional laser radar 100 and an outward rotation drive mechanism 200.

[0033] Specifically, the two-dimensional laser radar 100 can perform distance measurement on targets located in various directions within a predetermined scanning plane a, with one point as the origin, and obtain corresponding distance data; the specific structure of the two-dimensional laser radar 100 is exemplified herein, and includes a laser, a receiver, a processing unit, and an internal rotation mechanism. The laser can emit a laser beam of a specific wavelength, usually in a pulsed form, and it will periodically emit short pulses of laser. The receiver can capture the laser pulses reflected back by the target and convert them into electrical signals. The processing unit controls the emission timing of the laser and processes the received reflected signals. The internal rotation mechanism can be a motor-driven mirror, or it can directly rotate the entire laser emission and receiving module to achieve a 360-degree scan within a plane.

[0034] The external rotation drive mechanism 200 is used to drive the two-dimensional laser radar 100 to rotate around an external rotation axis, wherein the external rotation axis is set at a non-parallel and non-vertical angle relative to the scanning plane a, that is, the angle formed between the external rotation axis and the scanning plane a is an acute angle (greater than 0° and less than 90°) or an obtuse angle (greater than 90° and less than 180°).

[0035] In the present invention, since the external rotation axis is set at a non-parallel and non-vertical angle relative to the scanning plane a, that is, there is a spatial angle between the external rotation axis and the scanning plane a, therefore, during the rotation of the two-dimensional laser radar 100, its scanning plane a will actually form a series of different inclination angles, thereby converting the original two-dimensional distance data into three-dimensional coordinates.

[0036] Based on the present invention, by combining the two-dimensional laser radar 100 with the tilt-rotating external rotation drive mechanism 200, the present invention realizes the collection of three-dimensional point cloud data. Compared with the traditional 3D laser radar, the present invention achieves the same positioning accuracy in low-speed scenarios (<1m / s) through the combination of low-cost 2D radar and mechanical structure innovation. Specifically, the rotational motion of the two-dimensional laser radar 100 and the tilt angle work together to solve the three-dimensional coordinates (x, y, z) of each ranging point in a fixed coordinate system, solving the problem that cost and accuracy cannot be achieved at the same time in traditional solutions. In addition, the tilt-rotation design reduces the sensitivity to obstruction by vertical obstacles (such as trees and eaves) and improves the adaptability in complex outdoor environments.

[0037] like Figures 1 to 4As shown, in the embodiment of the present invention, the external rotation drive mechanism 200 includes a rotating base 210 and a driving assembly 220. The rotating base 210 includes a rotating body 211 and a connecting plate 212, the rotating body 211 is connected to the two-dimensional laser radar 100, the connecting plate 212 is connected to one end of the rotating body 211, and an extension portion 2121 is extended to the periphery, and the extension portion 2121 is provided with a plurality of through holes for bolts to pass through, wherein the bolts pass through the through holes and can be screwed to the two-dimensional laser radar 100 to achieve the connection between the connecting plate 212 and the two-dimensional laser radar 100; the driving assembly 220 is used to drive the rotating body 211 to rotate around the external rotation axis.

[0038] Based on this structural design, since the outer periphery of the connecting plate 212 extends out an extension portion 2121, and the extension portion 2121 is provided with a plurality of through holes for bolts to pass through, during the assembly process, the connection between the connecting plate 212 and the two-dimensional laser radar 100 can be completed by passing the bolts through the through holes and screwing with the two-dimensional laser radar 100. This assembly method significantly reduces the difficulty of assembly, and the structural design increases the connection area, which allows the bolts to be larger in size, thereby ensuring the stability between the two-dimensional laser radar 100 and the rotating base 210. In addition, the detachability of the bolt connection facilitates equipment maintenance and upgrading, and reduces maintenance costs.

[0039] Furthermore, in the embodiment of the present invention, the rotating body 211 and the connecting plate 212 are integrally structured, and the integrally formed rotating body 211 and the connecting plate 212 eliminate assembly errors and improve the rigidity and stability of the overall structure. This design reduces the number of parts and connection interfaces, reduces the risk of mechanical failure, simplifies the production process, and reduces manufacturing costs. For example, the integral die-casting of aluminum alloy material not only meets the lightweight requirements, but also improves the deformation resistance, and is suitable for vibration or impact environments.

[0040] In addition, in order to realize the power supply of the two-dimensional laser radar 100, a conductive slip ring connection is provided between the rotating base 210 and the driving assembly 220, which can realize the rotating base 210 to rotate unidirectionally for multiple consecutive circles. Of course, it can also be a wireless data transmission in the form of an optical coupler, and then cooperate with the wireless power transmission in the form of a wireless charging coil.

[0041] like Figures 1 to 3As shown, in an embodiment of the present invention, the driving assembly 220 includes a motor structure 221, a driving wheel 222, a driven wheel 223 and an annular conveyor belt 224. The motor structure 221 is used to drive the driving wheel 222 to rotate. The annular conveyor belt is arranged around the outer peripheral surface of the driving wheel 222 and the driven wheel 223. The driving wheel 222 drives the driven wheel 223 to rotate synchronously through the annular conveyor belt, and the driven wheel 223 is connected to the rotating body 211. The motor structure 221 drives the driving wheel 222 to rotate, and transmits power to the driven wheel 223 through the annular conveyor belt 224, thereby driving the rotating body 211 to rotate around the outer rotation axis. This belt transmission method has the advantages of stable transmission and low noise, and can effectively reduce the impact of vibration and impact on the equipment. In addition, it can also be in the form of motor direct drive, gear drive or worm gear drive, which also has the advantages of stable transmission and low noise, and can effectively reduce the impact of vibration and impact on the equipment.

[0042] Furthermore, the rotating body 211 is cylindrical, and the central axis of the rotating body 211 coincides with the external rotation axis, that is, the central axis of the rotating body 211 coincides with the central axis of the driven wheel 223. In this way, during the production process, the assembly condition between the rotating body and the driven wheel 223 can be quickly understood by observing the appearance of the rotating body 211 and the driven wheel 223. Through such a design, the three-dimensional coordinates of the points scanned by the radar at each moment in the fixed coordinate system can be more accurately calculated, providing more accurate positioning information for the garden robot, improving the robot's operating efficiency and safety in complex environments such as gardens, and solving the problems of insufficient accuracy and poor stability in traditional positioning solutions.

[0043] like Figures 1 to 3 As shown, in an embodiment of the present invention, the radar positioning device also includes a rotary encoder 300, and the rotary encoder is used to determine the rotation angle of the rotating body 211. The rotary encoder 300 provides key parameters for three-dimensional coordinate solution by real-time monitoring of the angle change of the rotating body 211, and then combines the time synchronization algorithm and linear interpolation to accurately match the laser radar ranging data and the rotation angle. For example, when the laser radar measures the distance d at time t1, the encoder synchronously records the rotation angle φ at this time. Through the coordinate conversion formula (x=d·cosθ·cosφ, y=d·sinθ·cosφ, z=h+d·sinθ·sinα), the three-dimensional coordinates of the point in the fixed coordinate system can be solved. This process realizes the real-time conversion of two-dimensional data to three-dimensional point cloud, providing an accurate environmental model for robot positioning.

[0044] Specifically, the rotary encoder 300 includes a code disk 310, at least one group of photoelectric sensors 320 and a signal processing unit. The code disk 310 is connected to the rotating body 211. A plurality of code ports arranged at intervals are provided on the outer circumference of the code disk 310. The photoelectric sensor 320 includes at least one pair of light emitters and light receivers, which are symmetrically arranged on both sides of the code disk 310, so that the code ports turn on or off the light path when rotating to generate corresponding pulse signals. The signal processing unit is connected to the photoelectric sensor 320 and is used to calculate the rotation angle based on the number of pulses.

[0045] Among them, the coordinated design of the code opening of the code disk 310 and the photoelectric sensor 320 realizes non-contact angle measurement, reduces mechanical wear and improves reliability. In order to ensure the accuracy of angle measurement, multiple code openings are not evenly spaced. In a specific implementation, it is preferred to make one of the gaps of different widths to serve as a mark of the rotation starting point. The symmetrical layout of the photoelectric sensor 320 (the light transmitter and the receiver are respectively located on both sides of the code disk 310) enhances the signal's anti-interference ability and can work stably even in dust or strong light environments. The signal processing unit calculates the rotation angle by counting the number of pulses, and combined with the timestamp synchronization algorithm, it can provide angle resolution to ensure the accuracy of the three-dimensional coordinate solution.

[0046] It should be noted here that the rotary encoder 300 can also measure the external rotation of the two-dimensional laser radar 100 in other ways, such as by combining a magnet and a Hall sensor for measurement.

[0047] See also Figure 3 In the embodiment of the present invention, the line passing through the origin and perpendicular to the scanning plane a is the radar central axis; the external rotation axis intersects with the radar central axis.

[0048] When the two-dimensional laser radar 100 rotates around the external rotation axis, the angle between its scanning plane a and the external rotation axis remains constant, ensuring that the projections of all ranging points in three-dimensional space have a uniform geometric relationship, simplifying the coordinate conversion algorithm and reducing the computational complexity. At the same time, this spatial position relationship is also conducive to optimizing the uniformity of point cloud data, avoiding local data sparseness or overlap problems caused by scanning trajectory offset, and improving the integrity of three-dimensional environment modeling.

[0049] like Figures 1 to 3 As shown, in the embodiment of the present invention, the radar positioning device further includes a mounting base 400;

[0050] The external rotation drive mechanism 200 is mounted on the mounting base 400. The mounting base 400 provides a stable support structure for the entire device. The radar positioning device can be conveniently mounted on a robot platform (such as the top of a lawn mowing robot) through the mounting base 400, and the scanning range of the radar can be optimized by adjusting the mounting angle of the mounting base 400.

[0051] Specifically, the mounting base 400 is rotatably connected to the rotating base 210 via a bearing.

[0052] In an embodiment of the present invention, the external rotation drive mechanism 200 drives the two-dimensional laser radar 100 to rotate within a preset speed range and generates disturbances during the rotation process. The disturbance refers to the random change of the rotation speed between the upper and lower limits of the preset speed range. For example, the speed may fluctuate and change randomly between 98rpm (rotations per minute) and 102rpm. In the traditional uniform rotation, the two-dimensional laser radar 100 may scan periodically repeated scanning areas and data sparse areas. The present invention adds a disturbance strategy to change the scanning speed of the two-dimensional laser radar 100, avoiding data overlap and omission, and the three-dimensional point cloud data at each location has sufficient data volume.

[0053] The present invention also proposes a garden robot, which includes a radar positioning device. The specific structure of the radar positioning device refers to the above-mentioned embodiment. Since the garden robot adopts all the technical solutions of all the above-mentioned embodiments, it also has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0054] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A radar positioning device, characterized in that: include: A two-dimensional laser radar can measure the distance of a target in each direction within a predetermined scanning plane with one point as the origin, and obtain the corresponding distance data; The external rotation drive mechanism is used to drive the two-dimensional laser radar to rotate around an external rotation axis, wherein the external rotation axis is set at a non-parallel and non-vertical angle relative to the scanning plane.

2. The radar positioning device according to claim 1, characterized in that: The outward rotation driving mechanism comprises: A rotating base, comprising a rotating body and a connecting plate, wherein the rotating body is connected to the two-dimensional laser radar, the connecting plate is connected to one end of the rotating body and extends an extension portion to the periphery, the extension portion is provided with at least one through hole for a bolt to pass through, wherein the bolt passes through the through hole and can be screwed to the two-dimensional laser radar to achieve connection between the connecting plate and the two-dimensional laser radar; The driving assembly is used to drive the rotating body to rotate around the outer rotation axis.

3. The radar positioning device according to claim 2, characterized in that: The driving assembly includes a motor structure, a driving wheel, a driven wheel and an annular transmission belt. The motor structure is used to drive the driving wheel to rotate. The annular transmission belt is wrapped around the outer circumference of the driving wheel and the driven wheel. The driving wheel drives the driven wheel to rotate synchronously through the annular transmission belt. The driven wheel is connected to the rotating body.

4. The radar positioning device according to claim 3, characterized in that: The rotating body is cylindrical, and the central axis of the rotating body coincides with the outer rotation axis.

5. The radar positioning device according to claim 2, characterized in that: The radar positioning device further comprises a rotary encoder, and the rotary encoder is used to determine the rotation angle of the rotating body.

6. The radar positioning device according to claim 5, characterized in that: The rotary encoder includes a code disk, at least one group of photoelectric sensors and a signal processing unit. The code disk is connected to the rotating body. A plurality of code ports arranged at intervals are provided on the outer circumference of the code disk. The photoelectric sensor includes at least one pair of light emitters and light receivers, which are symmetrically arranged on both sides of the code disk so that the code ports turn on or off the light path when rotating to generate corresponding pulse signals. The signal processing unit is connected to the photoelectric sensor and is used to calculate the rotation angle according to the number of pulses.

7. The radar positioning device according to claim 1, characterized in that: The line passing through the origin and perpendicular to the scanning plane is the radar centerline; The outer rotation axis intersects the radar central axis.

8. The radar positioning device according to claim 1, characterized in that: The radar positioning device also includes a mounting base; The outward rotation driving mechanism is installed on the installation base.

9. The radar positioning device according to claim 1, characterized in that: The external rotation drive mechanism drives the two-dimensional laser radar to rotate within a preset rotation speed range and generates disturbances during the rotation process.

10. A garden robot, characterized in that: It comprises a radar positioning device as claimed in any one of claims 1 to 9.

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