A blade lifting vehicle posture regulation method based on digital simulation

Abstract

This invention relates to the fields of wind power engineering technology, transportation safety, and three-dimensional digital simulation technology. It discloses a method for controlling the attitude of a blade lifting vehicle based on digital simulation, comprising: establishing a multi-condition coupled motion simulation environment for the blade lifting vehicle; acquiring a swept envelope in the multi-condition coupled motion simulation environment, performing safety clearance analysis and conflict detection, and formulating a blade lifting vehicle attitude control strategy; conflicts include transmission line conflicts and tree conflicts; the blade lifting vehicle attitude control strategy includes generating an attitude adjustment sequence and clearing trees within a minimum obstacle clearance range; during simulated vehicle passage, acquiring real pose feedback information, intervening in blade attitude, and realizing blade lifting vehicle attitude control. According to the above technical solution, the optimal combination of obstacle clearance and attitude adjustment can be found through simulation optimization, achieving the highest safety redundancy with minimal ecological damage and economic cost.

Description

Technical Field

[0001] This invention relates to the fields of wind power engineering technology, transportation safety and three-dimensional digital simulation technology, and more specifically, to a method for controlling the attitude of a blade lifting vehicle based on digital simulation. Background Technology

[0002] In the construction of mountain wind power projects, the design of transportation routes for large components requires collaboration among multiple departments. As the length of wind turbine blades continues to increase, their transportation has become a major challenge in wind farm construction. When navigating rural roads and mountain bends, blade lifting vehicles often encounter the dual obstacles of overhead power lines and trees on both sides of the road. Traditional transportation safety management relies primarily on the experience and visual estimation of drivers and supervisors, making it impossible to accurately quantify and assess the distance and sweep space between the blade tip and obstacles during the multi-degree-of-freedom complex movements of vehicle turning, blade lifting, and tool rotation. If, based on conservative estimates, large-scale, indiscriminate felling of trees on both sides of the power line is carried out, it will not only cause unnecessary ecological damage but may also damage power equipment such as power poles; secondly, the unclear assessment of risks may leave safety hazards, or improper operations such as sudden stops in uncertain situations may lead to safety accidents.

[0003] Therefore, there is an urgent need for a method to control the attitude of the blade lifting vehicle based on high-precision digital terrain data. By scientifically assessing road transport conditions and modification strategies, this method can accurately quantify collision risks and adjust the attitude when carrying out transport work on complex mountain roads, achieving safe passage at the lowest cost, reducing unnecessary engineering and cost investment, and ultimately providing reliable technical support for the safe transport of large wind power equipment in mountainous areas. Summary of the Invention

[0004] To achieve the above objectives, this application provides a method for controlling the attitude of a blade lifting vehicle based on digital simulation, comprising the following steps: A multi-condition coupled motion simulation environment for the blade lifting vehicle was established. This environment includes a 3D digital environment model and a cable model. Independent forest model And a model of the blade lifting vehicle system; including the cable model. The spatial curve, fitted from the measured key points, is represented by the equation of the spatial curve. ,in These are curve parameters; the blade lifting vehicle system model consists of a blade lifting vehicle model and a blade model. Obtaining the swept envelope in a multi-condition coupled motion simulation environment Safety clearance analysis and conflict detection were conducted to formulate blade lifting vehicle attitude control strategies. Conflicts included power line conflicts and tree conflicts. The blade lifting vehicle attitude control strategies included generating attitude adjustment sequences and clearing trees within the minimum clearance range. During the simulated vehicle passage process, real position and posture feedback information is obtained to intervene in the blade attitude and realize the attitude control of the blade lifting vehicle.

[0005] Furthermore, before establishing a multi-condition coupled motion simulation environment, data acquisition and basic modeling are carried out, and a model of the blade lifting vehicle system is constructed. In multi-condition coupled motion simulation, the blade lifting vehicle system model is placed into the three-dimensional digital environment model, the path of the vehicle through the curve is planned, the blade lifting vehicle system model is driven to simulate the vehicle traveling along the path, and the blade model is synchronously controlled to simulate the blade performing lifting, pitching and rotation actions.

[0006] During data acquisition, measurement data and high-precision point cloud data are obtained; during basic modeling, a 3D digital environment model and a cable model are established based on the measurement data and high-precision point cloud data. and independent forest model .

[0007] Among them, the swept space envelope The set of key discrete points on the blade surface of the recorded blade model { The spatial position is constituted by the vehicle pose transformation matrix. Pose transformation matrix of the vehicle relative to the blade Joint decision, indicating as = ,in For point The initial coordinates.

[0008] The safety clearance analysis and conflict detection includes the following steps: Determine the minimum safe clearance between the blade and the obstacle. ; During the simulation of a vehicle traveling along a path using a blade lifting vehicle model, the shortest spatial distance between the swept envelope and the obstacle model is calculated in real time. Identify all The conflict and its location; among which, the shortest spatial distance Including envelope With cable model shortest distance between and envelope To the The shortest distance between trees If it exists Then it is determined that a power line collision has occurred at that location; if If so, a forest conflict is determined to have occurred at that location: Based on the identified conflicts and their locations, and with the goal of avoiding conflicts, a blade lifting vehicle attitude control strategy is formulated.

[0009] Among them, the envelope With cable model shortest distance between The calculation method is as follows: solve for each discrete point to curve nearest point parameter , represented as: For all Take the minimum value to obtain the envelope. With cable model shortest distance between ; Envelope To the The shortest distance between trees The calculation method is as follows: each independent forest model Abstractly, it can be represented as a generalized cylindrical or conical envelope with the trunk's centerline as its axis and the outer contour of the crown as its boundary. Let the first... The abstract model of a tree is Calculate the first Trees and each discrete point distance , represented as: ,in, The center point of the base of the tree trunk, The direction vector of the central axis of the tree trunk. Represents the cross product of vectors. For point ground elevation, For the height of the tree crown Horizontal expansion radius at the location; envelope To the The shortest distance between trees for: .

[0010] Furthermore, the process of generating the attitude adjustment sequence includes: While keeping the vehicle path unchanged, adjust the horizontal rotation angle of the blade at a specified position point in the simulation. and lifting angle Update the shortest distance Determine the updated shortest distance Are there any transmission line conflicts? If there are no transmission line conflicts, determine the horizontal rotation angle. and lifting angle Then perform a horizontal rotation at the next position. and lifting angle Adjustment; adjustment of horizontal rotation angle during simulated transportation. and lifting angle Iterative updates generate attitude adjustment sequences.

[0011] Clear minimum clearance area The process of defining the area for clearing trees within the area includes: analyzing the interference between leaves and trees during the conflict; vertically projecting the three-dimensional interference volume corresponding to the interference part onto the ground to obtain an irregular polygon as the operating circle; expanding the operating circle outward by a specified distance according to the mechanical operation margin; and obtaining the area is the minimum clearance range. Clear the minimum clearance area The trees inside.

[0012] Furthermore, in response to transmission line conflicts, a blade lifting vehicle attitude control strategy was developed to generate an attitude adjustment sequence. To address forest conflict, a blade lifting vehicle attitude control strategy is developed to generate an attitude adjustment sequence; if conflict cannot be avoided, the blade lifting vehicle attitude control strategy is developed to clear the minimum clearance area. The trees inside.

[0013] Furthermore, generating the attitude adjustment sequence also includes: by horizontal rotation angle and lifting angle Adjustment update of shortest distance Determine the updated shortest distance Are there any conflicts between trees? If there are no conflicts between trees, determine the horizontal rotation angle. and lifting angle Then perform a horizontal rotation at the next position. and lifting angle Adjustment; adjustment of horizontal rotation angle during simulated transportation. and lifting angle Iterative updates generate attitude adjustment sequences.

[0014] According to this invention, the optimal combination of obstacle removal and attitude adjustment can be found through simulation optimization, achieving the highest safety redundancy with minimal ecological damage and economic cost. Furthermore, this invention integrates the entire process of measurement, modeling, simulation, analysis, decision-making, and execution, forming a closed-loop management system. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating the blade lifting vehicle attitude control method based on digital simulation according to an embodiment of the present invention. Figure 2This is a schematic diagram of a vertical blade lifting vehicle system provided in an embodiment of the present invention; Figure 3 It is a three-dimensional digital environment model provided according to an embodiment of the present invention; Figure 4 This is a schematic diagram of a blade lifting vehicle passing through a power transmission line, according to an embodiment of the present invention. Detailed Implementation

[0016] The specific implementation of the present invention will now be described in detail with reference to the accompanying drawings.

[0017] The blade lifting vehicle attitude control method based on digital simulation provided by this invention is as follows: Figure 1 As shown, it includes the following steps: Step S100: Establish a multi-condition coupled motion simulation environment for the blade lifting vehicle, specifically including the following steps: Step S101: Before establishing a multi-condition coupled motion simulation environment, data acquisition and basic modeling are performed first.

[0018] During data acquisition, total stations and other surveying equipment were used to measure the three-dimensional coordinates of multiple key points along the transmission line to construct measurement data. Unmanned aerial vehicle (UAV) photogrammetry technology was employed to acquire images of the target area and reconstruct a realistic 3D model. Simultaneously, UAVs equipped with lidar were used to scan the target area, acquiring high-precision point cloud data to identify and locate each tree to be evaluated. Key points included the locations of towers and the lowest point of sag, and the measurement data included the coordinates of key sag points on the transmission line and the coordinates of characteristic points on the treetops.

[0019] In the basic modeling stage, the real-world 3D scene obtained from laser scanning and UAV aerial surveying is fused to create a 3D digital environment model that includes obstacles. For example... Figure 3 As shown, the three-dimensional digital environment model is a high-precision geometric model of obstacles constructed in a simulation environment based on measurement data. The construction process includes fitting spline curves to the measurement data of the transmission line to construct a cable model formed by a catenary or parabolic model. High-precision point cloud data is classified and processed to generate independent forest models. Terrain model and road surface model.

[0020] Among them, cable model The spatial curve, fitted from the measured key points, is represented by the equation of the spatial curve. ,in Curve parameters ( ).

[0021] Step S102: Establishing a multi-condition coupled motion simulation environment also requires constructing a blade lifting vehicle system model; the blade lifting vehicle system model consists of a blade lifting vehicle model and a blade model; the blade lifting vehicle model is a multibody dynamics model of the blade lifting vehicle, which includes the chassis, lifting mechanism and slewing mechanism of the blade lifting vehicle; the blade model is a multi-rigid-body kinematics model of the blade, used to describe the degrees of freedom of the blade in the lifting, pitching and yaw directions.

[0022] When building the blade lifting vehicle model, based on the design drawings of the blade lifting vehicle, models of key components such as the chassis, hydraulic lifting cylinder, and slewing platform are created in multibody dynamics software, defining their kinematic pairs and drive relationships. The blade model can be simplified as a system composed of multiple rigid sections connected flexibly. The connection relationship between the mounting interface at the blade root and the slewing platform of the lifting vehicle is defined. Under the operation of the tooling platform, the blade can rotate 360° horizontally and lift within a spatial range of 0-30°. The blade lifting vehicle system model must be able to reflect key actions such as the lifting mechanism and tooling rotation. Figure 2 A schematic diagram of the blade lifting vehicle system is provided, in which the blades are lifted at angles of 5°, 10°, 15°, 20°, 25° and 30° from left to right.

[0023] Step S103: During multi-condition coupled motion simulation, the blade lifting vehicle system model is placed into the three-dimensional digital environment model. The path of the vehicle through the curve is planned, and the blade lifting vehicle system model is driven to simulate the vehicle traveling along the path. The blade model is controlled synchronously to simulate the blade performing lifting, pitching and turning actions. The global coordinates of each point on the blade profile (such as the leading edge, trailing edge and blade tip) at each moment during the motion process are calculated and recorded.

[0024] The global coordinates at all times constitute a point cloud, which is the sweep space envelope representing the blade motion. Specifically, record the set of key discrete points on the blade surface { The spatial position of the vehicle is determined by the vehicle pose transformation matrix. Pose transformation matrix of the vehicle relative to the blade Joint decision, indicating as = ,in For point The initial coordinates; The union of the elements constitutes the swept envelope. .

[0025] Step S110: Obtain the swept envelope in the multi-condition coupled motion simulation environment. Conduct safety clearance analysis and conflict detection, and formulate blade lifting vehicle attitude control strategies; Clearance analysis and collision detection include the following steps: Step S111: Determine the minimum safe clearance between the blade and the obstacle. ; Determine the minimum safe clearance When calculating the voltage level of the transmission line, the safety distance corresponding to the voltage level, the margin of measurement and model error, and the additional sway caused by dynamic wind load need to be considered. The calculation formula is as follows: = + + ,in To maintain a safe distance according to regulations, To comprehensively model and measure errors, To account for the dynamic displacement caused by wind load.

[0026] Step S112: During the simulated vehicle travel along the path using the blade lifting vehicle model, calculate the shortest spatial distance between the swept envelope and the obstacle model in real time. Identify all The points of conflict and their locations.

[0027] 1) First, identify conflicts and their locations while simulating the vehicle traveling along the path, and calculate the shortest spatial distance. Shortest spatial distance Including envelope With cable model shortest distance between and envelope To the The shortest distance between trees ; Specifically: blade sweep envelope It can be discretized into a large set of points { },in , This represents the number of discrete points used to characterize the envelope. To cable model space curves The Euclidean distance is: ,in This represents the 2-norm of a vector (i.e., the Euclidean distance).

[0028] Envelope To cable model shortest distance Defined as the minimum distance from all discrete points to the curve, expressed as: ; In actual simulation calculations, firstly, for each discrete point... The solution to the curve is obtained by numerical methods. nearest point parameter To obtain the shortest distance to that point Then for all The envelope can be obtained by taking the minimum value. With cable model shortest distance between .

[0029] Each individual forest model Abstractly, it can be represented as a generalized cylindrical or conical envelope with the trunk's centerline as its axis and the outer contour of the crown as its boundary. Let the first... The abstract model of a tree is Then for the discrete point set of the blade sweep envelope { },point To the tree surface The method for calculating the shortest distance is: point The shortest distance to the central axis of the tree trunk minus the effective radius of the canopy at that height. ,in The height of the point; specifically, the distance. Represented as: ,in, The center point of the base of the tree trunk, The direction vector of the central axis of the tree trunk. Represents the cross product of vectors. For point ground elevation, For the height of the tree crown The horizontal radius of expansion at that location; if If it is negative, it indicates a point. Penetrating the tree canopy envelope, the distance is measured as 0.

[0030] At this time, the envelope To the The shortest distance between trees for: .

[0031] For the envelope With cable model and individual tree models shortest distance between and Perform a judgment; if it exists Then it is determined that a power line collision has occurred at that location; if If so, it can be determined that a conflict of interest has occurred at that location.

[0032] Step S113: Based on the identified conflicts and the location where the conflicts occur, and with the goal of avoiding conflicts, formulate a blade lifting vehicle attitude control strategy.

[0033] To address transmission line conflicts, a blade lifting vehicle attitude control strategy was developed, which involved generating an attitude adjustment sequence. The specific development process included adjusting the horizontal rotation angle of the blades at specified locations during simulation, while keeping the vehicle path unchanged. and lifting angle By horizontal rotation angle and lifting angle Adjustment update of shortest distance Determine the updated shortest distance Are there any transmission line conflicts? If there are no transmission line conflicts, determine the horizontal rotation angle. and lifting angle Then perform a horizontal rotation at the next position. and lifting angle Adjustment; adjustment of horizontal rotation angle during simulated transportation. and lifting angle Iterative updates generate an attitude adjustment sequence; this sequence is used as the basis for blade adjustments during actual transport. Iterative simulations verify that if the blade lift angle is finely adjusted from 25° to 20°, then... The height can be increased to 2.1 meters. Based on this, a sequence of attitude adjustment is generated to control the blade angle during transport. The blade lift angle smoothly transitions from 25° to 20° and then recovers according to a specific curve. Furthermore, it can be combined with the horizontal rotation angle. and lifting angle Adjustments are made to generate an attitude adjustment sequence in order to achieve a more refined attitude control strategy for the blade lifting vehicle. Figure 4 This is a schematic diagram of a real-world simulation of a blade lifting vehicle model passing through a power transmission line. The red dots represent key points of the power transmission line's sag and characteristic points of treetops; the yellow lines represent the cable model.

[0034] To address forest conflict, a blade lifting vehicle attitude control strategy was developed to support the generation of attitude adjustment sequences; during the generation of attitude adjustment sequences, the horizontal rotation angle was used... and lifting angle Adjustment update of shortest distance Determine the updated shortest distance Are there any conflicts between trees? If there are no conflicts between trees, determine the horizontal rotation angle. and lifting angle Then perform a horizontal rotation at the next position. and lifting angle Adjustment; adjustment of horizontal rotation angle during simulated transportation. and lifting angle Iterative updates generate an attitude adjustment sequence. If conflicts cannot be avoided, a blade lifting vehicle attitude control strategy is formulated to clear the minimum obstacle clearance area. The specific process involves analyzing the interference between leaves and trees during the conflict, vertically projecting the corresponding three-dimensional interference volume onto the ground to obtain an irregular polygon as the operating circle, and expanding the operating circle outward by a specified distance (e.g., 0.5 meters) according to the mechanical operation margin. The resulting area is the minimum clearance range. According to the blade lifting vehicle attitude control strategy, clear the minimum obstacle clearance area. The trees within the area can ensure smooth transportation.

[0035] The final comprehensive safe passage plan incorporates the minimum clearance area. The trees and leaves within the forest adjust in real time according to their posture sequence.

[0036] Step S120: During the simulated vehicle passage process, obtain real position and posture feedback information, intervene in blade posture, and adjust the blade lifting vehicle posture.

[0037] Before actual on-site operations, the minimum clearance area should be determined. The system precisely prunes and fells designated trees. During transportation, the generated blade attitude control sequence is coordinated with the transport vehicle for operation. The vehicle travels along the planned path, performing fine-tuning of the blade angle and rotation. Simultaneously, it acquires real-time pose feedback information from the field operation (such as real-time position and attitude), updates the simulated environment with this feedback information, adjusts the blade lifting vehicle's attitude control strategy, and further achieves blade lifting vehicle attitude control.

[0038] This invention simulates key behaviors of a blade lifting vehicle, such as straight-line movement, turning, blade lifting, and tooling rotation, in a digital twin environment consistent with real-world scenarios. It accurately calculates the sweep space range of the vehicle and carrier for each behavior, visually demonstrating the blade transportation process and improving scenario realism and on-site intuitiveness. This enables a shift from a decision-making model based on "experience-based judgment" to one based on "simulation verification." Furthermore, based on specific distance values ​​and angle commands, this invention achieves measurable and reproducible technical processing of planning experience; it transforms passive observation during transportation into proactive pre-transportation simulation planning, allowing for the early detection and resolution of all potential conflicts. The blade lifting vehicle attitude control method provided by this invention can find the optimal combination of obstacle clearing and attitude adjustment through simulation optimization, achieving maximum safety redundancy with minimal ecological damage and economic cost. Moreover, this invention integrates the entire process of measurement, modeling, simulation, analysis, decision-making, and execution, forming a closed-loop management system.

[0039] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the present invention is not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A method for controlling the attitude of a blade lifting vehicle based on digital simulation, characterized in that, Includes the following steps: Establish a multi-condition coupled motion simulation environment for the blade lifting vehicle; The multi-condition coupled motion simulation environment includes a three-dimensional digital environment model and a cable model. Independent forest model And a model of the blade lifting vehicle system; including the cable model. The spatial curve, fitted from the measured key points, is represented by the equation of the spatial curve. ,in These are curve parameters; the blade lifting vehicle system model consists of a blade lifting vehicle model and a blade model. Obtain the swept envelope in the multi-condition coupled motion simulation environment Safety clearance analysis and conflict detection are performed to formulate blade lifting vehicle attitude control strategies; the conflicts include power line conflicts and tree conflicts; the blade lifting vehicle attitude control strategies include generating attitude adjustment sequences and clearing trees within the minimum obstacle clearing range; During the simulated vehicle passage process, real position and posture feedback information is obtained to intervene in the blade attitude and realize the attitude control of the blade lifting vehicle.

2. The blade lifting vehicle attitude control method based on digital simulation according to claim 1, characterized in that, Before establishing the multi-condition coupled motion simulation environment, data acquisition and basic modeling are carried out, and a model of the blade lifting vehicle system is constructed. During multi-condition coupled motion simulation, the blade lifting vehicle system model is placed into a three-dimensional digital environment model, the path of the vehicle through the curve is planned, the blade lifting vehicle system model is driven to simulate the vehicle traveling along the path, and the blade model is synchronously controlled to simulate the blade performing lifting, pitching and rotation actions.

3. The blade lifting vehicle attitude control method based on digital simulation according to claim 2, characterized in that, During data acquisition, measurement data and high-precision point cloud data are obtained; during basic modeling, a three-dimensional digital environment model and a cable model are established based on the measurement data and high-precision point cloud data. and independent forest model .

4. The blade lifting vehicle attitude control method based on digital simulation according to claim 2, characterized in that, The sweeping space envelope The set of key discrete points on the blade surface of the recorded blade model { The spatial position is constituted by the vehicle pose transformation matrix; the spatial position is constituted by the vehicle pose transformation matrix. Pose transformation matrix of the vehicle relative to the blade Joint decision, indicating as = ,in For point The initial coordinates.

5. The blade lifting vehicle attitude control method based on digital simulation according to claim 1, characterized in that, The safety clearance analysis and collision detection include the following steps: Determine the minimum safe clearance between the blade and the obstacle. ; During the simulation of a vehicle traveling along a path using a blade lifting vehicle model, the shortest spatial distance between the swept envelope and the obstacle model is calculated in real time. Identify all The conflict and its location; wherein, the shortest spatial distance Including envelope With cable model shortest distance between and envelope To the The shortest distance between trees If it exists Then it is determined that a power line collision has occurred at that location; if If so, a forest conflict is determined to have occurred at that location: Based on the identified conflicts and their locations, and with the goal of avoiding conflicts, a blade lifting vehicle attitude control strategy is formulated.

6. The blade lifting vehicle attitude control method based on digital simulation according to claim 5, characterized in that, The envelope With cable model shortest distance between The calculation method is as follows: solve for each discrete point to curve nearest point parameter , is represented as: For all Take the minimum value to obtain the envelope. With cable model shortest distance between ; Envelope To the The shortest distance between trees The calculation method is as follows: each independent forest model Abstractly, it can be represented as a generalized cylindrical or conical envelope with the trunk's centerline as its axis and the outer contour of the crown as its boundary. Let the first... The abstract model of a tree is Calculate the first Trees and each discrete point distance , is represented as: ,in, The center point of the base of the tree trunk, The direction vector of the central axis of the tree trunk. Represents the cross product of vectors. For point ground elevation, For the height of the tree crown Horizontal expansion radius at the location; envelope To the The shortest distance between trees for: .

7. The blade lifting vehicle attitude control method based on digital simulation according to claim 5, characterized in that, The process of generating the attitude adjustment sequence includes: While keeping the vehicle path unchanged, adjust the horizontal rotation angle of the blade at a specified position point in the simulation. and lift angle Update the shortest distance Determine the updated shortest distance Are there any transmission line conflicts? If there are no transmission line conflicts, determine the horizontal rotation angle. and lift angle Then perform a horizontal rotation at the next position. and lift angle Adjustment; adjustment of horizontal rotation angle during simulated transportation. and lift angle Iterative updates generate attitude adjustment sequences.

8. The blade lifting vehicle attitude control method based on digital simulation according to claim 5, characterized in that, The minimum clearance area The process of defining the area for clearing trees within the area includes: analyzing the interference between leaves and trees during the conflict; vertically projecting the three-dimensional interference volume corresponding to the interference part onto the ground to obtain an irregular polygon as the operating circle; expanding the operating circle outward by a specified distance according to the mechanical operation margin; and obtaining the area is the minimum clearance range. Clear the minimum clearance area The trees inside.

9. The blade lifting vehicle attitude control method based on digital simulation according to claim 1, characterized in that, In response to transmission line conflicts, a blade lifting vehicle attitude control strategy was developed to generate an attitude adjustment sequence. To address forest conflict, a blade lifting vehicle attitude control strategy is developed to support the generation of attitude adjustment sequences; if conflict cannot be avoided, the blade lifting vehicle attitude control strategy is developed to clear the minimum obstacle clearance area. The trees inside.

10. The blade lifting vehicle attitude control method based on digital simulation according to claim 9, characterized in that, The generation of the attitude adjustment sequence further includes: adjusting the horizontal rotation angle. and lift angle Adjustment update of shortest distance Determine the updated shortest distance Are there any conflicts between trees? If there are no conflicts between trees, determine the horizontal rotation angle. and lift angle Then perform a horizontal rotation at the next position. and lift angle Adjustment; adjustment of horizontal rotation angle during simulated transportation. and lift angle Iterative updates generate attitude adjustment sequences.

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