Wheel type tree climbing and pruning robot and control method thereof

Abstract

The invention relates to the technical field of robots, and discloses a wheel type tree climbing and pruning robot and a control method thereof.The robot comprises a robot body, and a driving wheel assembly and a supporting wheel assembly are installed on the outer wall of the robot body; the outer wall of the hydraulic driving module is mounted on one side of the robot body; the outer wall of the pressure feedback module is mounted in the supporting wheel assembly; the outer wall of the control unit is mounted in the robot body; the lower surface of the laser radar module is mounted on the upper surface of the supporting wheel assembly; the outer wall of the three-dimensional modeling module is mounted in the robot body; a pruning execution device; and an energy module. Through a hydraulic driving system and a pressure feedback mechanism, the attaching force between the supporting wheels and the tree trunk can be adjusted in real time, it is ensured that the robot stably moves on the complex surface of the tree trunk, and the problems of unstable attaching and insufficient control precision are solved.

Description

Technical Field

[0001] This invention relates to the field of robotics, specifically to a wheeled tree-climbing and pruning robot and its control method. Background Technology

[0002] Existing tree-climbing robots mostly use simple drive methods, such as electric motors or chain drive systems, to control their movement. This method often fails to guarantee stable adhesion when facing complex tree trunk surfaces. The robot's adhesion is poor, and it is prone to slipping or detaching from the trunk. Low control precision also affects the efficiency and accuracy of the operation. In contrast, this invention uses a hydraulic drive system and a pressure feedback mechanism to precisely adjust the adhesion force, thereby improving the robot's stability and movement accuracy.

[0003] Existing path planning technologies often rely on basic sensors, such as simple collision sensors or basic vision sensors. These sensors cannot accurately capture the complex morphology of tree trunks, and their accuracy and adaptability are poor in complex tree environments. Path planning optimization is often not intelligent enough, easily leading to unnecessary energy waste and low movement efficiency. In contrast, this invention, through a lidar module and 3D modeling technology, can accurately acquire spatial information of tree trunks and optimize path planning, better adapting to the complex environment of trees.

[0004] In traditional pruning methods, the force control of pruning tools often relies on manual operation or simple electric devices. This method cannot adjust the pruning force according to the actual conditions of different trees, resulting in unstable pruning results and potentially causing branch tearing or failed pruning. Traditional pruning devices usually do not take into account the differences in wood density and branch diameter, affecting the quality of pruning. This invention, however, ensures pruning quality and effectively reduces tree damage by precisely adjusting the pruning force and direction. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a wheeled tree-climbing pruning robot and its control method, which solves the problems of unstable adhesion, inaccurate path planning, and low pruning precision of existing pruning robots in complex tree trunk environments.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a wheeled tree-climbing and pruning robot, comprising: The robot body has a drive wheel assembly and a support wheel assembly installed on its outer wall, which are used to move in close contact with the tree trunk. A hydraulic drive module, the outer wall of which is installed on one side of the robot body, and the other end is located on one side of the drive wheel assembly and the support wheel assembly, for controlling the contact force of each support wheel; A pressure feedback module, wherein the interior of the support wheel assembly is installed on the outer wall of the pressure feedback module, is used to detect the contact pressure between the support wheel and the tree trunk in real time; The control unit, whose outer wall is installed inside the robot body, adjusts the output of the hydraulic drive module according to the detection results of the pressure feedback module. A lidar module, the lower surface of which is mounted on the upper surface of the support wheel assembly, is used to collect spatial information of the tree trunk; A 3D modeling module is installed inside the robot body. The 3D modeling module is electrically connected to a lidar module and is used to generate a 3D structural model of the tree trunk based on the data collected by the lidar module. A pruning execution device, the outer wall of which is mounted on the upper surface of the robot body, is used to identify pruning targets and perform pruning operations based on the three-dimensional structural model; An energy module, which is installed on the outer wall of the robot body, includes a solar power supply unit and a wind power supply unit to provide power support.

[0007] Preferably, the hydraulic drive module includes several hydraulic cylinders and proportional valves, with each hydraulic cylinder corresponding to a support wheel to provide adjustable positive pressure so that the robot body fits against the tree trunk surface.

[0008] Preferably, the pressure feedback module includes a flexible diaphragm pressure sensor, which is positioned at the contact points between each support wheel and the tree trunk to acquire the contact pressure per unit area and convert it into an analog signal for processing by the main control unit.

[0009] Preferably, the control unit adopts a closed-loop control method. Based on the difference between the preset reference pressure and the current feedback pressure, it calculates and outputs a control signal through a proportional, integral, and derivative controller, thereby adjusting the driving pressure of the hydraulic cylinder to achieve stable fitting control.

[0010] Preferably, the tree trunk model constructed by the 3D modeling module is used to calculate the path for the robot to crawl around the tree trunk, and the path planning is optimized with stability index and energy consumption index as objective functions.

[0011] Preferably, the bonding stability index is calculated based on the deviation between the actual pressure at each contact point between the robot and the tree trunk and the set reference pressure, and the energy consumption index is evaluated based on the energy usage of the drive system per unit time.

[0012] Preferably, the pruning execution device includes an electric shearing arm and an angle adjustment structure. The control unit calculates the shearing direction and force based on the pruning target point identified by the three-dimensional model, and drives the shearing arm to perform the pruning operation.

[0013] Preferably, the cutting direction is the direction with the smallest angle to the target branch axis, and the cutting force is determined based on the target branch diameter and wood density parameters to achieve the optimal cutting effect and avoid branch tearing.

[0014] Preferably, in the energy module (7), the solar power supply unit includes a deployable solar panel, the wind power supply unit includes a wind power generation device installed on one side of the robot, and the control unit automatically adjusts the power supply priority of each energy unit according to the ambient light intensity and wind speed to achieve the optimization of energy output efficiency.

[0015] A control method for a wheeled tree-climbing and pruning robot includes the following steps: S1. Push the robot body to make the drive wheel assembly contact the tree, and adjust the position of the support wheel assembly to contact the tree by activating the hydraulic drive module; S2. By activating the lidar module, the tree trunk and its surrounding environment are scanned from multiple angles to obtain point cloud data of the outer surface of the tree trunk. The point cloud data is then input into the 3D modeling module to construct a spatial model of the tree trunk and extract feature parameters for motion planning, including the tree trunk radius, surface curvature, branch distribution location and direction information. S3. Calculate the crawling path of the robot around the tree trunk based on the 3D model. The path aims to reduce energy consumption and improve the stability of the fit. S4. Drive the wheel assembly to move at a constant or variable speed according to the path control, and collect the contact pressure signal of each support wheel assembly in real time through the pressure feedback module during the movement. Compare it with the set reference pressure. If the pressure deviates from the set range, adjust the output pressure of the corresponding hydraulic drive module through closed-loop control. S5. When the robot body approaches the pruning target point, the spatial coordinates of the pruning point are determined based on the spatial position, diameter and orientation information of the branches identified by the 3D modeling module, and the target pose parameters of the pruning execution device are calculated. S6. Match the corresponding shearing force according to the mechanical parameters of the branches and control the shearing device to perform the shearing action. Monitor the shearing resistance in real time during the shearing process and compensate appropriately to prevent the branches from tearing or breaking. S7. After pruning is completed, control the robot body to continue moving along the path and execute the next pruning task until all target points are pruned. S8. Throughout the operation, based on external environmental parameters such as light intensity and wind speed, dynamically assess the availability of solar and wind energy, and control the energy module (7) to automatically switch or combine the power supply modes of solar panels and wind power generation devices.

[0016] This invention provides a wheeled tree-climbing and pruning robot and its control method. It has the following beneficial effects: 1. This invention, through a hydraulic drive system and pressure feedback mechanism, can adjust the contact force between the support wheels and the tree trunk in real time, ensuring stable movement of the robot on complex tree trunk surfaces. Unlike the simple drive methods in existing technologies, this invention can precisely adjust the pressure, avoiding problems such as unstable contact and insufficient control precision, and significantly improving the stability and accuracy during operation.

[0017] 2. This invention uses a lidar module to collect spatial information of tree trunks and combines it with a 3D modeling module to generate a tree trunk model, enabling the robot to accurately identify trees and plan paths. Unlike existing path planning methods that rely solely on simple sensors, this invention optimizes paths through 3D modeling, better addressing complex tree environments and significantly improving the efficiency and adaptability of pruning tasks.

[0018] 3. This invention, through its pruning execution device, can precisely adjust the cutting force according to the diameter and wood density of the branches, avoiding the problems of branch tearing or failed pruning that are common in traditional pruning methods. By accurately calculating the cutting direction and force, this invention ensures optimal pruning results while reducing the risk of tree damage and improving pruning quality.

[0019] 4. This invention integrates solar and wind power supply units through an energy module, automatically adjusting the power supply method according to ambient light intensity and wind speed, thus optimizing energy efficiency. Unlike existing devices with a single power source, this invention significantly extends the robot's operating time through a dual energy supply scheme, while reducing dependence on external power sources, achieving a more efficient and environmentally friendly operating method. Attached Figure Description

[0020] Figure 1 This is a system framework diagram of the present invention; Figure 2 This is a perspective view of the device of the present invention; Figure 3 This is a side view of the present invention; Figure 4 This is a partial structural cross-sectional view of the present invention.

[0021] The components include: 1. Robot body; 2. Drive wheel assembly; 3. Hydraulic drive module; 4. LiDAR module; 5. Pruning actuator; 6. Support wheel assembly; 7. Energy module; 8. Pressure feedback module; 9. Control unit; and 10. 3D modeling module. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Please see the appendix Figure 1 This invention provides a wheeled tree-climbing and pruning robot, comprising: The robot body 1 has a drive wheel assembly 2 and a support wheel assembly 6 installed on its outer wall, which are used to move around the tree trunk in a close-fitting manner. Specifically, in this embodiment, the robot body 1 serves as the core support for all functional modules. It not only houses components such as the hydraulic drive system, sensors, and control unit 9, but is also closely linked to key tasks such as contact, movement, and stability of the tree trunk. The robot body 1 is the basic structure of the entire robot, ensuring the coordinated operation of all systems and modules.

[0024] In this embodiment, the robot body 1 is made of a robust yet lightweight alloy material to ensure sufficient compressive strength and rigidity, while reducing overall weight for ease of movement and adaptability to various tree trunk environments. The robot body 1 is equipped with a hydraulic drive system, a control unit 9, a pressure feedback sensor, an energy supply module, and other components. Each module is connected via a highly integrated communication interface, enabling close collaboration among the parts and ensuring efficient execution of the robot's movement and pruning tasks.

[0025] The support structure of the robot body 1 consists of multiple support wheels distributed around the tree trunk. These support wheels are hydraulically driven and can be dynamically adjusted according to the shape and roughness of the tree trunk. Specifically, the support wheels are controlled by hydraulic cylinders and hydraulic valves to provide sufficient pressure on the tree trunk to ensure that the robot body 1 can stably attach to the trunk surface. Each support wheel is independently controlled by a hydraulic system, which includes multiple hydraulic cylinders and proportional valves, and can adjust the contact force with the tree trunk according to the movement state of the robot body 1.

[0026] The hydraulic drive module 3 has its outer wall installed on one side of the robot body 1, and its other end is located on one side of the drive wheel assembly 2 and the support wheel assembly 6, and is used to control the contact force of each support wheel. Specifically, in this embodiment, the hydraulic drive module 3 is used to drive specific components in the system, and its working principle and structural configuration need to be coordinated with the previous modules to ensure the efficient operation of the entire system. The hydraulic drive module 3 controls movement through the fluid pressure provided by the hydraulic power source, and typically works in conjunction with hydraulic pumps, hydraulic valves, and other hydraulic components to achieve precise mechanical control.

[0027] The flow rate and pressure of the hydraulic oil in the hydraulic drive module 3 can be controlled by a hydraulic pump, and the output flow rate of the hydraulic pump is related to the load of the drive system. To ensure the working efficiency of the hydraulic drive module 3, the hydraulic pump is usually equipped with a flow regulating device that automatically adjusts the flow rate according to the load to maintain system stability.

[0028] Specifically, the operating state of the hydraulic drive module 3 is closely related to changes in the hydraulic pressure within the system. The function of the hydraulic valves is to adjust the flow path of the hydraulic oil according to control signals, thereby controlling the movement of the hydraulic cylinders. Hydraulic valves typically have multiple operating modes, including but not limited to directional valves, pressure regulating valves, and flow regulating valves. The selection of each valve depends on specific application requirements and system configuration.

[0029] The hydraulic drive module 3 includes an adjustable-pressure hydraulic pump connected to the hydraulic cylinder via oil pipes. A pressure sensor and a flow control valve are installed in the oil pipes. The pressure sensor monitors the hydraulic pressure in the system in real time and adjusts the output pressure and flow of the hydraulic pump based on feedback signals. In this way, the system can automatically adjust the output power of the hydraulic drive module 3 according to load changes, thereby ensuring the efficient and stable operation of the entire drive system.

[0030] For the formula part in hydraulic drive module 3, it is assumed that the pressure and flow rate in the hydraulic drive system have the following relationship; ; in, The pressure of the hydraulic oil; The force acting on the hydraulic cylinder; This represents the area of ​​the hydraulic cylinder piston.

[0031] The power of a hydraulic drive system can be given by the following formula; ; in, This refers to the output power of the hydraulic drive system. This refers to the output force of the hydraulic cylinder. The speed of the hydraulic cylinder; For system efficiency.

[0032] The efficiency of a hydraulic system is closely related to the flow resistance of the hydraulic oil, frictional losses, and the operating conditions of each component. During the design process, it is necessary to optimize various parameters of the system based on the specific operating conditions of the application to improve overall efficiency.

[0033] The hydraulic drive module 3 employs a flow-sharing technology, using multiple hydraulic cylinders connected in parallel or series to distribute the load. The working pressure and flow rate of each hydraulic cylinder can be adjusted via an independent hydraulic valve, thereby achieving synchronous control of multiple moving parts.

[0034] Pressure feedback module 8, the inside of support wheel assembly 6 is installed on the outer wall of pressure feedback module 8, and is used to detect the contact pressure between support wheel and tree trunk in real time; Specifically, in this embodiment, its main function is to monitor the contact pressure between the robot's support wheels and the tree trunk in real time and feed this information back to the control unit 9 to achieve precise closed-loop control, thereby ensuring that the robot can stably crawl and complete pruning tasks under various tree trunk shapes and surface conditions. The pressure feedback module 8 adjusts the hydraulic system through real-time pressure signals, thereby adjusting the contact force of the support wheels to maintain stable contact with the tree trunk.

[0035] In this embodiment, the pressure feedback module 8 includes multiple pressure sensors and related signal processing modules, mainly used to detect pressure changes in the contact area between the robot support wheel and the tree trunk. These sensors are typically flexible diaphragm pressure sensors, installed on the contact surface between the robot support wheel and the tree trunk, and can convert pressure signals into analog voltage signals and transmit them to the control unit 9.

[0036] Each support wheel is equipped with at least one pair of pressure sensors. The sensor's output signal is proportional to the pressure applied to the support wheel. Specifically, the pressure sensors work by sensing the pressure in the contact area when the support wheel contacts the tree trunk surface and generating a corresponding electrical signal. This electrical signal is converted into a digital signal by an analog signal processing circuit and then transmitted to the central control unit 9. The central control unit 9 calculates the actual pressure value between each support wheel and the tree trunk through real-time processing of the sensor signals.

[0037] The real-time pressure data from the pressure feedback module 8 can be used to adjust the pressure of the hydraulic cylinder. The control unit 9 compares this data with a preset reference pressure value and calculates the necessary adjustment value. Based on the pressure error, the control unit 9 sends a control signal to adjust the output pressure of the hydraulic cylinder to achieve appropriate pressure between the support wheel and the tree trunk. For example, when the pressure feedback signal is lower than the set reference value, the control unit 9 increases the output of the hydraulic cylinder, forcing the support wheel to press firmly against the tree trunk; conversely, it decreases the output of the hydraulic cylinder, reducing the contact force of the support wheel to avoid damage to the tree trunk.

[0038] In practical implementation, the pressure feedback module 8 can be adjusted through a series of feedback control algorithms. In some embodiments, the control unit 9 employs a proportional-integral-derivative (PID) control algorithm, processing the difference between the actual pressure signal fed back by the pressure sensor and the predetermined pressure value. This PID control algorithm has high real-time performance and accuracy, ensuring that the robot's support wheels are always in optimal contact with the tree trunk.

[0039] Specifically, the set reference pressure value Compared with the actual measured pressure value The error between them is ΔP, that is: ; This represents the pressure difference, which is the difference between the reference pressure and the actual pressure. The reference pressure value is a pre-set standard pressure value; The actual pressure value is the pressure value obtained in actual measurement.

[0040] Based on this error, the output signal of the PID controller can be expressed as: ; in, For control output, it is usually the output signal of a PID controller; The proportional gain is the proportional coefficient of the controller. It determines the relationship between the controller output and the error. proportional relationship; For error; The integral gain is the integral coefficient of the controller. This is the integral term, representing the accumulation of error over time; The differential gain is the differential coefficient of the controller. The differential term represents the rate of change of the error.

[0041] The pressure feedback module 8 of this invention monitors the contact pressure between the support wheel and the tree trunk in real time and adjusts the hydraulic system using the feedback signal, ensuring the robot's stable and reliable operation in various environments. The introduction of this system allows the robot to flexibly respond to changes in tree trunk surface conditions and ensures optimal operational performance through closed-loop control.

[0042] Control unit 9, the outer wall of control unit 9 is installed inside the robot body 1, and adjusts the output of hydraulic drive module 3 according to the detection result of pressure feedback module 8; Specifically, in this embodiment, the main function of the control unit 9 is to receive data from various modules and adjust the robot's operating state in real time based on this data to ensure that the robot can stably and efficiently complete the tree climbing and pruning tasks. The design of the control unit 9 determines the robot's overall working efficiency and operational stability, especially when facing complex terrain, different tree species, and diverse environmental conditions, the control unit 9 adjusts through its precise algorithms.

[0043] In this embodiment, the control unit 9 uses a microprocessor or dedicated control chip as its core processing unit and communicates with each module through a multi-channel data input and output interface. Specifically, the control unit 9 not only needs to receive data from the pressure feedback module 8, the lidar module 4, and other sensors, but also needs to perform real-time analysis and decision-making based on this data, and issue corresponding control commands to adjust the hydraulic drive system, pruning actuator, etc.

[0044] The control unit 9 works closely with the pressure feedback module 8, the hydraulic drive module 3, and the robot body 1. In the pressure feedback module 8, sensors monitor the contact pressure between the support wheel and the tree trunk in real time and convert it into an analog signal, which is then sent to the control unit 9. The control unit 9 compares this data with a set reference pressure value and adjusts the output pressure of the hydraulic drive system using a PID control algorithm. This ensures that the support wheel maintains a suitable contact force with the tree trunk, thereby ensuring the stability of the crawling process.

[0045] The control unit 9 also possesses path planning and optimization functions. It plans the path based on data from the LiDAR module 4. By creating a 3D model of the tree trunk surface, branch distribution, and environmental obstacles, the control unit 9 calculates the optimal crawling path and updates it in real time during robot movement. During path planning, the control unit 9 aims for "minimum energy consumption" and "optimal contact stability," determining the best route by calculating the contact pressure distribution between the support wheels and the tree trunk, avoiding unnecessary energy waste, and ensuring stability during crawling.

[0046] In one possible implementation, control unit 9 uses the following optimization algorithm for path planning: ; in, The objective function for path optimization; For the first Pressure at each contact point; For the first Displacement error at each contact point; This represents the number of contact points.

[0047] The control unit 9 optimizes the robot's motion path according to the objective function to minimize overall energy consumption and ensure path stability.

[0048] The control unit 9 plays a central role in this invention. By monitoring data from each module in real time and making precise adjustments and optimizations, it not only ensures the robot's stability in changing environments but also improves the robot's execution efficiency in different tasks.

[0049] The lower surface of the lidar module 4 is mounted on the upper surface of the support wheel assembly 6, and is used to collect spatial information of the tree trunk. Specifically, in this embodiment, the LiDAR module 4 serves as a crucial perception system, working closely with modules such as the pressure feedback system, path planning module, and pruning execution device. The main function of the LiDAR module 4 is to acquire three-dimensional spatial information of the tree trunk, generate high-precision point cloud data, and transmit it to the control unit 9 for processing. Through this data, the control unit 9 can accurately identify the shape and size of the tree trunk and the distribution of branches, thus providing fundamental support for subsequent path planning, pressure adjustment, and pruning tasks. The precise perception capability of the LiDAR, especially its performance in complex environments, determines the stability and efficiency of the robot when performing tasks.

[0050] In this embodiment, the lidar module 4 adopts a 360° omnidirectional scanning design, enabling real-time acquisition of spatial data around the trees. This module emits a laser beam and receives the signal reflected back from the tree trunk surface, thereby calculating the distance and spatial position of each point. The lidar module 4 has high resolution, allowing it to scan detailed information of the tree trunk surface in a short time, providing accurate point cloud data.

[0051] Specifically, the lidar module 4 operates according to the following principles through the transmission and reception of laser beams: ; in, This is the distance the laser beam travels from the lidar source to the tree trunk surface and back. The speed of light; This is the time from laser emission to reception.

[0052] The lidar module 4 calculates the distance from each scanning point to the lidar according to the formula, thereby obtaining the spatial position of each point on the tree trunk surface. All the collected point cloud data is transmitted to the control unit 9 to generate a three-dimensional digital model of the tree trunk.

[0053] The LiDAR module 4 gradually collects environmental data through rotational scanning, forming a high-density 3D point cloud map. By processing and filtering this point cloud data, the system can remove noise points and maintain high data accuracy. After the point cloud data is processed by the 3D modeling module, the control unit 9 plans a path based on information such as the shape and size of the tree trunk and the distribution of branches, ensuring stable contact between the robot and the tree trunk surface.

[0054] The LiDAR module 4 plays a crucial role in the wheeled tree-climbing and pruning robot of this invention. It not only provides the control unit 9 with precise three-dimensional spatial data but also provides the necessary geometric information for subsequent path planning, pressure adjustment, and pruning tasks. Through the collaboration of the LiDAR module 4 and other modules, the robot can operate stably in changing environments and complete efficient pruning tasks.

[0055] The 3D modeling module 10 is installed inside the robot body 1. The 3D modeling module 10 is electrically connected to the lidar module 4 and is used to generate a 3D structural model of the tree trunk based on the data collected by the lidar module 4. Specifically, in this embodiment, the 3D modeling module 10 is a key module for achieving high-precision tree trunk modeling and path planning. This module processes the point cloud data acquired by the LiDAR module 4 to construct a 3D digital model of the tree trunk and extract its geometric features, such as trunk radius, surface curvature, and branch distribution. This geometric information provides necessary support for the robot's subsequent motion control, pruning operations, and pressure adjustment. The cooperation between the 3D modeling module 10, the LiDAR module 4, the control unit 9, the path planning module, etc., enables the robot to dynamically adjust based on real-time acquired environmental data, ensuring stability and efficiency during operation.

[0056] In this embodiment, the 3D modeling module 10 processes the LiDAR data and generates a 3D structural model of the tree trunk through the following steps. First, the LiDAR module 4 scans the environment around the tree to acquire point cloud data. The point cloud data includes the spatial coordinates of each point on the surface of the tree trunk. After acquiring the point cloud data, the 3D modeling module 10 preprocesses the data to remove noise points and abnormal data, thereby improving the accuracy and reliability of the data.

[0057] Specifically, after filtering and denoising, the point cloud data is spatially reconstructed using a 3D reconstruction algorithm. By interpolating and fitting the spatial position of each point in the point cloud data to a surface, the 3D modeling module 10 can construct the 3D shape of the tree trunk. Generally, the 3D reconstruction algorithm can employ a surface reconstruction method based on Delaunay triangulation to transform irregular point cloud data into a continuous surface model. Specifically, the 3D modeling module 10 uses the following reconstruction method: ; in, A three-dimensional surface model representing the surface of a tree trunk; This represents each point in the point cloud data; This represents the surface fitting function.

[0058] Using this formula, the 3D modeling module 10 can generate a detailed 3D model of the tree trunk based on the point cloud data collected by the lidar.

[0059] The 3D modeling module 10 can also calculate the characteristic parameters of the tree trunk, such as the radius variation, curvature, and surface shape, based on the point cloud data of the trunk. The extraction of these parameters is crucial for subsequent pruning tasks. For example, the control unit 9 can determine the optimal pruning position based on the radius variation of the tree trunk and adjust the pressure distribution of the support wheels according to the curvature of the tree trunk surface to ensure the stability of the robot during the crawling process.

[0060] Specifically, the 3D modeling module 10 calculates the radius and curvature of the tree trunk using the following formula: ; in, This represents the average radius of the tree trunk; For the first The radius of each sampling point; The number of sampling points; Summing the reciprocals of the radii of all sampling points.

[0061] Using this formula, the 3D modeling module 10 can estimate the geometric features of the tree trunk, providing accurate data support for the path planning module and the pruning execution module.

[0062] Furthermore, the 3D modeling module 10 can also extract the position and orientation of branches by analyzing the branch distribution information in the point cloud data. In some embodiments, the 3D modeling module 10 uses a principal component analysis (PCA)-based method to identify the position of branches and their orientation relative to the trunk from the point cloud data. Specifically, the 3D modeling module 10 extracts the branch orientation using the following formula; ; in, The direction vector of the branch; For the first The location of each branch point; The average position of all branch points; This represents the number of branch points.

[0063] Using this method, the 3D modeling module 10 can accurately extract the direction and position of the branches, providing precise target positions and angles for pruning operations.

[0064] The 3D modeling module 10 in this invention processes and analyzes point cloud data collected by LiDAR to accurately generate a 3D structural model of the tree trunk, extracts the geometric features of the trunk, and provides important data support for path planning, pruning tasks, and stress adjustment. The design of this module ensures that the robot can achieve accurate tree trunk perception and efficient operation in complex environments.

[0065] The pruning execution device 5 is mounted on the upper surface of the robot body 1. It is used to identify the pruning target based on the three-dimensional structural model and to perform pruning operations. Specifically, in this embodiment, the pruning execution device 5, through its collaborative work with the control unit 9, the 3D modeling module 10, and the pressure feedback system, precisely completes the tree pruning task. The design of the pruning execution device 5 not only requires high-precision cutting capabilities but also necessitates adjusting the cutting force and angle according to the actual conditions of the trunk and branches to ensure efficiency and safety during the operation.

[0066] In this embodiment, the pruning actuator 5 consists of an electric pruning arm, an angle adjustment structure, and scissors. The pruning arm has multiple degrees of freedom, allowing it to rotate and extend according to the different orientations of the branch, ensuring that the scissors accurately reach the pruning position. The angle adjustment structure is used to adjust the angle between the scissors and the branch, ensuring that pruning resistance is minimized during pruning to avoid tearing of the branch or pruning failure.

[0067] Specifically, the pruning actuator 5 uses electrically driven tungsten carbide blades, with the blade opening and closing controlled by a motor. The shearing force is adjusted via the motor's speed and torque. Based on the tree structure data provided by the 3D modeling module 10, the control unit 9 calculates the thickness and position of the branches, thus providing real-time adjustments to the shearing force. The shearing force calculation is matched to parameters such as the branch diameter and wood density. During pruning, when the branch diameter is large, the control unit 9 increases the shearing force via motor control; when the branch is small or fragile, the control unit 9 reduces the shearing force to prevent branch breakage or uneven cut surfaces.

[0068] Generally, the shearing force is positively correlated with the diameter and density of the branch. To ensure shearing accuracy, the control unit 9 calculates the required shearing force using the following formula: ; in, Indicates shear force; The shear strength of the branch; This represents the effective contact area of ​​the shear blade.

[0069] When calculating shear force, shear strength The effective contact area is determined by the wood density and material properties of the branches. This is closely related to the diameter of the branch and the size of the scissors opening.

[0070] Fine-tuning of the shearing force can also be achieved through feedback from a pressure sensor. When the shears come into contact with the branch, the pressure sensor monitors the reverse pressure generated during the shearing process in real time and feeds this information back to the control unit 9. The control unit 9 determines the magnitude of the resistance during the shearing process based on the feedback pressure signal and adjusts the motor output accordingly to ensure a smooth and precise shearing process.

[0071] The working process of the pruning actuator 5 is as follows: Target identification and pruning path determination: Based on the tree trunk model generated by the 3D modeling module 10, the control unit 9 identifies the pruning target and calculates the pruning path to determine the pruning position and angle of each branch.

[0072] Shearing force calculation and adjustment: Based on the diameter of the branch, wood density and shearing target, the control unit 9 calculates the required shearing force and adjusts the shearing force according to the feedback signal.

[0073] Cutting angle adjustment: The angle adjustment structure adjusts the angle of the shears according to the spatial position of the cutting target to ensure the best cutting effect.

[0074] Performing the cutting operation: The electric drive system controls the scissors to perform precise cutting actions, ensuring that each cut achieves the intended effect.

[0075] In some embodiments, the pruning actuator 5 may also be equipped with a vision sensor to identify the actual position and shape of the branches and to fine-tune the pruning path and force based on real-time data. This design can further improve the robot's adaptability in complex environments and ensure the accuracy of pruning operations.

[0076] The pruning execution device 5 of this invention, through coordinated operation with modules such as the control unit 9, the three-dimensional modeling module 10, and the pressure feedback system, precisely executes tree pruning tasks. Its design not only ensures flexible adjustment of cutting force and angle but also adjusts various parameters during the pruning process through real-time feedback, ensuring both high efficiency and safety in the operation.

[0077] The energy module, which is installed inside the robot body, includes a solar power supply unit and a wind power supply unit, and is used to provide power support for the various modules of the robot; Specifically, the energy module provides continuous and stable energy output to all functional modules of the robot, especially ensuring power for the pruning actuator 5, the 3D modeling module 10, the control unit 9, the path planning system, and the wheel drive mechanism. The coupling between the energy module and each functional component must have good responsiveness and dynamic management capabilities to ensure that the robot can maintain stable energy efficiency and ensure task continuity while performing high-load tasks such as pruning and vertical crawling.

[0078] In this embodiment, the energy module uses a high-density lithium battery pack as the main power source. This battery pack has a built-in multi-level power management unit, supporting multi-channel constant voltage output and a fast load response mechanism. The module achieves bidirectional communication with the control unit 9 via a data bus, and can dynamically adjust the voltage and current output according to the robot's current state and task load, thereby rationally allocating power resources.

[0079] When the robot is stationary or in standby mode, the energy module 7 automatically reduces its output power and enters a low-power mode to extend its runtime. When the pruning actuator 5 or the drive wheel assembly is activated, the energy module immediately switches to a high-power output state to ensure that the energy needs of the corresponding actuators are met.

[0080] Specifically, the voltage, current, temperature and other parameters of each battery cell in the energy module are sampled in real time, and the power supply control strategy is scheduled based on the following basic power distribution model. ; in, Indicates the first Each functional module at time Instantaneous power demand; This is the operating voltage of the module; This is the operating current of the module.

[0081] Furthermore, to ensure the power system does not overload during parallel operation of multiple modules, the energy modules are equipped with redundant power supply channels and employ a rotating power supply strategy. This strategy dynamically adjusts the power supply priority based on the following load balancing function: ; in, This represents the current system load ratio; Representing the Each energy module at time Power output; This represents the maximum output power of the energy module; This indicates the number of energy modules in the working state.

[0082] The energy module in this invention not only possesses high-efficiency and highly responsive power supply capabilities, but also supports multi-level control strategies, temperature control protection mechanisms, and auxiliary energy acquisition mechanisms, ensuring a stable energy supply for the robot during complex pruning tasks. The collaborative operation of this module with the pruning execution device 5, the control system, the path decision module, etc., is an indispensable foundation for achieving efficient autonomous operation.

[0083] A control method for a wheeled tree-climbing and pruning robot; comprising the following steps; S1. Push the robot body 1 to make the drive wheel assembly 2 contact the tree, and adjust the position of the support wheel assembly 6 to contact the tree by activating the hydraulic drive module 3; Specifically, by pushing the robot body 1 to move the drive wheel assembly 2, the outer wall of the drive wheel assembly 2 comes into contact with the outer wall of the tree. Then, by activating the hydraulic drive module 3, the support wheel assembly 6 is moved, so that the wheels of the support wheel assembly 6 come into contact with the tree, thereby allowing the robot body 1 to be installed on the tree. The activation of the drive wheel assembly 2 drives the robot body 1 to move on the tree.

[0084] S2. By activating the lidar module 4, the tree trunk and its surrounding environment are scanned from multiple angles to obtain point cloud data of the outer surface of the tree trunk. The point cloud data is then input into the 3D modeling module to construct a spatial model of the tree trunk and extract feature parameters for motion planning, including the tree trunk radius, surface curvature, branch distribution location and direction information. The LiDAR module 4 scans the tree trunk and its surrounding environment. The LiDAR generates high-precision point cloud data of the tree trunk's outer surface by sending laser beams and receiving reflected signals. This data records the shape of the tree trunk surface and obstacles around the tree. Multi-angle scanning ensures complete 3D spatial data is obtained, facilitating subsequent 3D modeling and path planning.

[0085] S3. Calculate the crawling path of the robot around the tree trunk based on the 3D model. The path aims to reduce energy consumption and improve the stability of the fit. Next, the point cloud data is input into the 3D modeling module 10, which is used to accurately model the shape of the tree trunk. Based on the point cloud data, the 3D modeling module constructs a spatial model of the tree trunk and extracts key feature parameters, such as the trunk's radius, surface curvature, and the location and orientation of the branches. These feature parameters provide necessary information for subsequent motion planning. For example, the trunk's curvature can be used to determine the robot's posture adjustment during crawling, and the branch distribution helps in the precise positioning of the pruning task.

[0086] S4. Drive the wheel assembly 2 to move at a constant or variable speed according to the path control, and collect the contact pressure signal of each support wheel assembly 6 in real time through the pressure feedback module 8 during the movement. Compare it with the set reference pressure. If the pressure deviates from the set range, adjust the output pressure of the corresponding hydraulic drive module 3 through closed-loop control. After obtaining the 3D model and feature parameters of the tree trunk, the robot body 1 is moved by controlling the drive wheel assembly 2, thereby adjusting the movement path of the robot body 1 and increasing its movement speed. During movement, the pressure feedback module 8 detects the pressure changes of the wheels of the support wheel assembly 6. When the pressure deviates from the set range, the system adjusts the output pressure of the hydraulic cylinder through closed-loop control to ensure that the robot maintains a stable support state throughout the process. This closed-loop control method can avoid instability caused by insufficient or excessive pressure, thus ensuring efficient movement.

[0087] S4. When the robot body 1 approaches the pruning target point, the spatial coordinates of the pruning point are determined based on the spatial position, diameter and orientation information of the branches identified by the 3D modeling module, and the target pose parameters of the pruning execution device 5 are calculated. As the robot body 1 approaches the pruning target point, the control unit 9 accurately determines the spatial coordinates of the pruning point based on the branch position, diameter, and orientation information provided by the 3D modeling module. The system then calculates the target position of the pruning execution device 5 based on this data, i.e., the angle and position of the shears relative to the branch. At this point, the pruning task is about to begin; accurately calculating the pruning point and angle can prevent branch tearing or pruning failure.

[0088] S6. Match the corresponding shearing force according to the mechanical parameters of the branches and control the pruning execution device 5 to perform the shearing action. Monitor the shearing resistance in real time during the shearing process and compensate appropriately to prevent the branches from tearing or breaking. After determining the shearing point and angle, the control system calculates and matches the appropriate shearing force based on the branch's mechanical parameters, such as diameter, wood density, and fiber structure. Adjusting the shearing force is a crucial step; excessive force may tear the branch, while insufficient force may result in incomplete shearing. Therefore, the system monitors the shearing resistance in real time during the shearing process and adjusts the shearing force based on real-time feedback to ensure smooth shearing and effectively prevent branch tearing or failed shearing.

[0089] S7. After pruning is completed, control the robot body 1 to continue moving along the path and execute the next pruning task until all target points are pruned. After each pruning cycle, the control unit 9 automatically guides the robot body 1 to continue moving along the predetermined path to the next pruning target point. This process is continuous; the robot constantly adjusts its movement according to the path planning to ensure that all target branches are pruned, thus completing the pruning task of the entire tree.

[0090] S8. Throughout the operation, based on external environmental parameters such as light intensity and wind speed, dynamically assess the availability of solar and wind energy, and control the energy module 7 to automatically switch or combine the power supply modes of solar panels and wind power generation devices. Throughout the pruning operation, the energy module provides continuous power to the robot. The robot monitors external environmental parameters in real time, such as sunlight intensity and wind speed, using sensors. This data is used to dynamically assess the availability of solar and wind power. Based on these environmental parameters, the control system automatically switches or combines the power supply methods of solar panels and wind turbines to optimize energy efficiency and extend operation time. Specifically, solar panels provide priority power when sunlight is abundant, while wind turbines provide auxiliary energy when wind speeds are high.

[0091] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wheeled tree-climbing and pruning robot, characterized in that, include: The robot body (1) has a drive wheel assembly (2) and a support wheel assembly (6) installed on its outer wall for moving around the tree trunk in a close-fitting manner; The hydraulic drive module (3) has its outer wall installed on one side of the robot body (1) and its other end set on one side of the drive wheel assembly (2) and the support wheel assembly (6) to control the contact force of each support wheel; Pressure feedback module (8), the inside of the support wheel assembly (6) is installed on the outer wall of the pressure feedback module (8) for real-time detection of the contact pressure between the support wheel and the tree trunk; Control unit (9), the outer wall of which is installed inside the robot body (1), adjusts the output of hydraulic drive module (3) according to the detection result of pressure feedback module (8); A lidar module (4) is mounted on the upper surface of the support wheel assembly (6) on its lower surface, and is used to collect spatial information of the tree trunk. A three-dimensional modeling module (10) is installed on the outer wall of the robot body (1) and is electrically connected to the laser radar module (4) to generate a three-dimensional structural model of the tree trunk based on the data collected by the laser radar module (4). The pruning execution device (5) is mounted on the upper surface of the robot body (1) on its outer wall. It is used to identify the pruning target and perform pruning operations according to the three-dimensional structural model. The energy module (7) is installed on the outer wall of the robot body (1) and includes a solar power supply unit and a wind power supply unit for providing power support.

2. The wheeled tree-climbing and pruning robot according to claim 1, characterized in that, The hydraulic drive module (3) includes several hydraulic cylinders and proportional valves. Each hydraulic cylinder is set in correspondence with a support wheel to provide adjustable positive pressure so that the robot body fits against the surface of the tree trunk.

3. The wheeled tree-climbing and pruning robot according to claim 1, characterized in that, The pressure feedback module (8) includes a flexible membrane pressure sensor, which is set at the position where each support wheel contacts the tree trunk, and is used to obtain the contact pressure per unit area and convert it into an analog signal for processing by the main control unit.

4. The wheeled tree-climbing and pruning robot according to claim 1, characterized in that, The control unit (9) adopts a closed-loop control method. Based on the difference between the preset reference pressure and the current feedback pressure, it calculates and outputs a control signal through a proportional, integral and derivative controller, thereby adjusting the driving pressure of the hydraulic cylinder to achieve stable fitting control.

5. A wheeled tree-climbing and pruning robot according to claim 1, characterized in that, The tree trunk model constructed by the three-dimensional modeling module (10) is used to calculate the path of the robot crawling around the tree trunk. The path planning is optimized with the stability index and energy consumption index as objective functions.

6. A wheeled tree-climbing and pruning robot according to claim 5, characterized in that, The bonding stability index is calculated based on the deviation between the actual pressure at each contact point between the robot and the tree trunk and the set reference pressure, while the energy consumption index is evaluated based on the energy usage of the drive system per unit time.

7. A wheeled tree-climbing and pruning robot according to claim 1, characterized in that, The pruning execution device (5) includes an electric shearing arm and an angle adjustment structure. The control unit calculates the shearing direction and force based on the pruning target point identified by the three-dimensional model, and drives the shearing arm to perform the pruning operation.

8. A wheeled tree-climbing and pruning robot according to claim 7, characterized in that, The cutting direction is the direction with the smallest angle to the target branch axis, and the cutting force is determined based on the target branch diameter and wood density parameters to achieve the optimal cutting effect and avoid branch tearing.

9. A wheeled tree-climbing and pruning robot according to claim 1, characterized in that, In the energy module (7), the solar power supply unit includes a deployable solar panel, and the wind power supply unit includes a wind power generation device installed on one side of the robot. The control unit automatically adjusts the power supply priority of each energy unit according to the ambient light intensity and wind speed to achieve the optimization of energy output efficiency.

10. A control method for a wheeled tree-climbing and pruning robot, comprising the wheeled tree-climbing and pruning robot according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Push the robot body (1) to make the drive wheel assembly (2) contact the tree, and adjust the position of the support wheel assembly (6) to contact the tree by activating the hydraulic drive module (3); S2. By activating the lidar module (4), the tree trunk and its surrounding environment are scanned from multiple angles to obtain point cloud data of the outer surface of the tree trunk. The point cloud data is input into the three-dimensional modeling module to construct the spatial model of the tree trunk and extract the feature parameters for motion planning, including the tree trunk radius, surface curvature, branch distribution position and direction information. S3. Calculate the crawling path of the robot around the tree trunk based on the 3D model. The path aims to reduce energy consumption and improve the stability of the fit. S4. The drive wheel assembly (2) is controlled to move at a constant or variable speed according to the path. During the movement, the contact pressure signal of each support wheel assembly (6) is collected in real time through the pressure feedback module (8) and compared with the set reference pressure. If the pressure deviates from the set range, the output pressure of the corresponding hydraulic drive module (3) is adjusted through closed-loop control. S5. When the robot body (1) approaches the pruning target point, the spatial coordinates of the pruning point are determined based on the spatial position, diameter and orientation information of the branches identified by the three-dimensional modeling module, and the target pose parameters of the pruning execution device (5) are calculated. S6. Match the corresponding shearing force according to the mechanical parameters of the branches and control the shearing device (5) to perform the shearing action. Monitor the shearing resistance in real time during the shearing process and compensate appropriately to prevent the branches from tearing or failing to be cut. S7. After pruning is completed, control the robot body (1) to continue moving along the path and execute the next pruning task until all target points are pruned. S8. Throughout the operation, based on external environmental parameters such as light intensity and wind speed, dynamically assess the availability of solar and wind energy, and control the energy module (7) to automatically switch or combine the power supply modes of solar panels and wind power generation devices.

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