CN-121995914-A - Seedling plant protection robot and plant protection method thereof

CN121995914ACN 121995914 ACN121995914 ACN 121995914ACN-121995914-A

Abstract

The invention belongs to the technical field of agricultural robots, and particularly relates to a seedling plant protection robot and a plant protection method, wherein key points of an operation area are marked by an RTK dotter according to the sequence of 'head points-track points', as control vertexes, and 3-order B spline curve fitting operation paths are adopted in combination with vehicle body kinematic constraint; the plant protection robot advances along a path, synchronously collects operation parameters, calculates real-time pose by fusing the operation parameters through an extended Kalman filtering algorithm, recognizes and extracts a field ridge central line in real time by utilizing a vision system and a DeepLabV3+ model, calculates transverse deviation based on the pose and the central line, strictly controls the deviation by dynamically adjusting steering angles of steering wheels, intelligently switches the operation mode of the plant protection robot at a field head point, completes ridge-crossing movement and course adjustment, and circularly executes until the operation is finished. The method improves navigation precision, effectively avoids the risk of rolling seedlings, and improves operation robustness, environmental adaptability and operation efficiency.

Inventors

LV HAOTUN
LIU JUAN
WANG KUNYU
MA YIMING
DUAN XINGXING
Wei qiangwei
WANG QINGJIE

Assignees

中国农业大学

Dates

Publication Date: 20260508
Application Date: 20260127

Claims (10)

1. The plant protection method of the seedling plant protection robot is characterized by comprising the following steps of: s1, marking key points of a working area in sequence through an RTK dotter; s2, fitting an operation path by adopting a 3-order B spline curve based on the marked key points as control vertexes and combining with the hard constraint of the vehicle body kinematics; s3, starting the plant protection robot to start plant protection operation along an operation path, and synchronously collecting operation parameters of the plant protection robot; s4, based on the operation parameters of the plant protection robot, resolving the real-time pose of the plant protection robot through an extended Kalman filtering algorithm, and acquiring the center line of a field ridge in real time through a vision system; s5, acquiring the transverse deviation of the plant protection robot based on the real-time pose and the central line of the plant protection robot, dynamically adjusting the steering angle of a steering wheel of the plant protection robot based on the transverse deviation through a control system, and controlling the transverse position of the plant protection robot to keep a preset distance from the spacing between the ridge line of the field; S6, suspending the plant protection operation when the plant protection robot reaches a line feed boundary, switching a motion mode and adjusting steering angles of steering wheels of the plant protection robot through a control system, completing the movement of the plant protection robot to an adjacent ridge and the course adjustment, and continuing to travel the plant protection operation along the current ridge; and S7, repeating the steps S3 to S6 until the plant protection robot reaches the position corresponding to the end, stopping the plant protection robot, and ending the plant protection operation.
2. The plant protection method of a seedling plant protection robot according to claim 1, wherein the motion modes of the plant protection robot comprise an advancing double-ackerman mode, a transverse double-ackerman mode and a in-situ rotation mode, the advancing double-ackerman mode is used for enabling the plant protection robot to travel along a ridge straight line, the transverse double-ackerman mode is used for enabling the plant protection robot to move left and right along a direction perpendicular to the ridge to achieve ground head line feed, and the in-situ rotation mode is used for enabling the plant protection robot to turn in-situ to achieve course adjustment.
3. The plant protection method of a seedling plant protection robot of claim 2, wherein the plant protection robot moves toward adjacent ridges and heading adjusts, comprising the steps of: The mode of the plant protection robot is switched to a transverse double-Ackerman mode through the control system, so that the plant protection robot can move to adjacent ridges; And switching the mode of the plant protection robot into an in-situ rotation mode through a control system, so that steering wheels of the plant protection robot rotate according to a preset steering angle, and the course adjustment is completed.
4. The plant protection method of a seedling plant protection robot according to claim 1, wherein the vision system acquires the center line of the field ridge in real time, comprising the steps of: and acquiring a field RGB image through an RGB navigation camera, processing the field image by using a DeepLabV3+ semantic segmentation model, identifying a field ridge and extracting the central line of the field ridge.
5. The plant protection method of a seedling plant protection robot according to claim 1, wherein the lateral deviation of the plant protection robot is 0 cm-3 cm, and the lateral deviation of the plant protection robot is smaller than the distance between the central line of a field ridge and the seedlings.
6. The plant protection method of the seedling plant protection robot according to claim 2, wherein key points of a working area are marked in the sequence of 'track-field-head-spot', wherein the track-head-spot marks a working starting end, a finishing end and a line feed boundary, the track-field spots are arranged at intervals along the central line of a first ridge line, and the distance between the track-field-head spot and the track-field spot or between the track-field spot and the track-field spot is 15 m-25 m.
7. The plant protection method of a seedling plant protection robot of claim 1, wherein the hard constraints of body kinematics include steering angle range, upper travel speed limit and track curvature threshold of the plant protection robot.
8. The method according to claim 1, wherein the step S5 further comprises the steps of performing the on-off control of the spray heads on the plant protection robot based on the real-time pose of the plant protection robot, and dynamically adjusting the height of the spray heads to maintain the constant height of the spray heads from the ground, and adapting to different ridge distances, seedling heights and sloping field scenes.
9. A seedling plant protection robot for implementing the plant protection method according to any one of claims 1 to 8, comprising a robot body, further comprising: the independent steering driving steering wheel module is arranged at the bottom of the robot body and comprises four steering wheels which are independently driven and steering-adjusted, and the independent steering driving steering wheel module is used for realizing the mutual switching of an advancing double-Ackerman mode, a transverse double-Ackerman mode and an in-situ rotation mode; The pose detection system comprises an acquisition module and an algorithm module, wherein the acquisition module is used for acquiring the operation parameters of the plant protection robot, and the algorithm module is used for calculating the real-time pose of the plant protection robot through an extended Kalman filtering algorithm based on the operation parameters; The vision system is used for collecting field images in real time, identifying field ridges and acquiring center lines of the field ridges; A control system for performing the following functions: The method comprises the steps of obtaining key points marked on an operation area by an RTK dotter in sequence, taking the marked key points as control vertexes, combining with the hard constraint of vehicle body kinematics, fitting an operation path of a robot body, switching a motion mode of the robot body and adjusting steering angles of steering wheels according to the operation path to finish the movement and course adjustment of the robot body to adjacent ridges, dynamically adjusting the steering angles of the steering wheels of the robot body according to the real-time pose and the central line of the robot body, and correcting the transverse deviation of the robot body.
10. The seedling plant protection robot of claim 9, wherein the acquisition module comprises a wheel-type odometer, a dual-antenna RTK receiver and an IMU inertial measurement unit, the wheel-type odometer is used for acquiring travel speed and steering angle data of the robot body, the dual-antenna RTK receiver comprises a first dual-antenna RTK receiver and a second dual-antenna RTK receiver which are arranged at two sides of the running direction of the robot body and are used for acquiring absolute position coordinates and heading angles of the robot, and the IMU inertial measurement unit is used for acquiring triaxial angular speed and acceleration of the robot body.

Description

Seedling plant protection robot and plant protection method thereof Technical Field The invention belongs to the technical field of agricultural robots, and particularly relates to a seedling plant protection robot and a plant protection method thereof. Background The maize seedling stage is a key stage of maize growth, the seedling growth is slow at the stage, the field weeds are fast in growth, soil nutrients, moisture and illumination are easily contended, normal growth and development of maize are severely restricted, and therefore the plant protection operation in the stage is important for guaranteeing the maize yield. Most of the existing agricultural plant protection robots are improved and optimized based on traditional robots without avoiding crop rolling scenes, such as harvesting, cultivated land and the like, and the plant protection robots are provided with navigation configuration, but because the dependency of plant protection operation requirements on navigation is small, pure GPS/RTK navigation is often adopted, and when pure visual navigation is carried out, only simple directional control can be realized on the plant protection robots. In the plant protection process of spraying or fertilizing corn seedlings, the plant protection robot has poor navigation precision, influences the precision of plant protection operation, is fragile in corn seedling stems, needs to strictly travel along ridges, is difficult to consider global positioning and local ridge alignment precision, is weak in robustness, is easy to generate accumulated errors, causes rolling damage to the seedlings, and is poor in plant protection operation suitability. Disclosure of Invention In order to solve the problems in the prior art, the invention aims to provide the seedling plant protection robot and the plant protection method thereof, which can dynamically adjust the running track of the plant protection robot in the seedling plant protection process, reduce the transverse deviation, improve the ridge alignment precision, adapt to complex and changeable environmental changes and effectively avoid the rolling risk of seedlings. The technical scheme of the invention is as follows: A plant protection method of a corn seedling plant protection robot comprises the following steps: s1, marking key points of a working area in sequence through an RTK dotter; s2, fitting an operation path by adopting a 3-order B spline curve based on the marked key points as control vertexes and combining with the hard constraint of the vehicle body kinematics; s3, starting the plant protection robot to start plant protection operation along an operation path, and synchronously collecting operation parameters of the plant protection robot; s4, based on the operation parameters of the plant protection robot, resolving the real-time pose of the plant protection robot through an extended Kalman filtering algorithm, and acquiring the center line of a field ridge in real time through a vision system; s5, acquiring the transverse deviation of the plant protection robot based on the real-time pose and the central line of the plant protection robot, dynamically adjusting the steering angle of a steering wheel of the plant protection robot based on the transverse deviation through a control system, and controlling the transverse position of the plant protection robot to keep a preset distance from the spacing between the ridge line of the field; S6, suspending the plant protection operation when the plant protection robot reaches a line feed boundary, switching a motion mode and adjusting steering angles of steering wheels of the plant protection robot through a control system, completing the movement of the plant protection robot to an adjacent ridge and the course adjustment, and continuing to travel the plant protection operation along the current ridge; and S7, repeating the steps S3 to S6 until the plant protection robot reaches the position corresponding to the end, stopping the plant protection robot, and ending the plant protection operation. Preferably, the motion modes of the plant protection robot comprise an advancing double-ackerman mode, a transverse double-ackerman mode and a in-situ rotation mode, the advancing double-ackerman mode is used for enabling the plant protection robot to travel along a ridge straight line, the transverse double-ackerman mode is used for enabling the plant protection robot to move left and right along a direction perpendicular to the ridge to realize line feed of a ground head, and the in-situ rotation mode is used for enabling the plant protection robot to turn in situ to realize course adjustment. Preferably, the plant protection robot reaches the field head point to complete the movement and course adjustment of the plant protection robot to the adjacent ridges, and the method comprises the following steps: when the plant protection robot enters the field head point area, suspending the plant protection ope