[0023] In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with specific embodiments and with reference to the accompanying drawings.
[0024] Descriptions of structural embodiments and methods of the invention are disclosed herein. It should be understood that there is no intention to limit the invention to the particular disclosed embodiments, and that the invention can be practiced using other features, elements, methods and embodiments. Similar elements in different embodiments are generally labeled with similar numbers.
[0025] An embodiment of the present invention proposes a multi-tower vehicle synchronous travel control device, which is used to control the synchronous travel of multiple tower vehicles of a sprinkler irrigation machine. like figure 1 and figure 2 As shown, the device includes a navigation system control unit 1 and a motion control unit 2 . At least one motion control unit 2 is installed on each node of the tower truck, and the navigation system control unit 1 performs data communication with the motion control units 2 at multiple tower truck nodes through a star network of wireless data transmission stations.
[0026] The navigation system control unit 1 is used to generate differential data (including differential ranging error, pseudorange correction data, etc.) according to the received satellite ephemeris data, and send the differential data to the motion control unit 2 .
[0027] The motion control unit 2 is used to obtain the current position information of each tower truck node according to the differential data, and obtain the current heading information and speed information of each tower truck node, and combine the current position information, current heading information and speed information of each tower truck node. The speed information is sent to the navigation system control unit 1 through the wireless data transmission station for processing. The navigation system control unit 1 obtains the control parameters (i.e. the adjustment of motion posture) of each tower truck in the next state to walk synchronously according to the current position information, current heading information and speed information, and in conjunction with the walking path of each tower truck set in advance. data), and send the control parameters to the motion control unit 2, so that the motion control unit 2 controls each tower truck to walk synchronously according to the control parameters.
[0028] Specifically, the navigation system control unit 1 includes: a real-time kinematic (RTK) base station 3 , a central processing unit 9 , a wireless data transmission station 11 and a display screen 12 .
[0029] The RTK base station 3 generates differential data according to the received satellite ephemeris data, and the RTK base station 3 obtains its own position information through a single point positioning method, and establishes the base station position coordinates according to its own position information, as the subsequent processing of the position information of each tower truck. Reference coordinates; the central processor 9 is used to obtain the next state synchronization of each tower truck according to the current position information, heading information, speed information of each tower truck node of the motion control unit 2 and the preset walking path of each tower truck Walking control parameters, and after receiving the current position information of each tower truck node, the central processor 9 establishes a local local coordinate system according to the base station position coordinates, and performs local coordinate transformation on the current position information of each tower truck node. The position of the tower truck node fits a straight line in the local local coordinate system, and the straightness of the multi-tower truck synchronous walking of the sprinkler irrigation machine is obtained by calculating the variance of the shortest distance between the node position of each tower truck node and the straight line. Through this real-time straightness The detection can monitor the running status of each tower truck at any time, reduce the error before and after the multi-tower trucks travel, and improve the consistency of multi-tower trucks; the second wireless data transmission station 11 is used for data communication with the motion control unit 2; the display screen 12 It is used to display the walking path of multi-tower vehicles and set the working parameters of the sprinkler.
[0030] The motion control unit 2 includes: a real-time kinematic (RTK) mobile station 4 , a navigation controller 5 , a variable frequency motor control 6 , a variable frequency motor 7 , a tower span angle sensor 8 and a first wireless data transmission station 10 .
[0031]The real-time kinematic (RTK) mobile station 4 is used to obtain positioning data according to the differential data sent by the RTK base station 3. The RTK mobile station 4 is equipped with dual satellite receiving antennas, which are placed on the front and rear sides along the traveling direction of the tower truck; the frequency conversion motor control 6 is used To detect the voltage and current at the connection point between the variable frequency motor 7 and the variable frequency motor control 6 to obtain the actual operating frequency and rotational speed of the variable frequency motor 7; the tower span angle sensor 8 is installed at the connection between the tower car and the tower frame (between the two towers) , used to measure the tower span angle of each tower car (the forward direction of the tower car and the inclination angle of the tower); the navigation controller 5 is used to solve the positioning data, actual operating frequency and speed, and the tower span angle, and obtain each tower span angle through the positioning data. The current position information of the tower truck nodes, the current heading information of each tower truck node is obtained through the tower span angle combined with the 4 antenna position data of the RTK mobile station, and the current speed information of each tower truck node is obtained through the actual operating frequency and rotation speed of the frequency conversion motor 7. The first wireless data transmission station 10 is used to send position information, heading information and speed information to the navigation system control unit 1, and receive the control parameters of multi-tower synchronous walking sent by the navigation system control unit.
[0032] Among them, the data communication between the navigation system control unit 1 and the motion control unit 2 is real-time, that is, the position information, heading information and speed information are obtained in real time, and the heading information and speed of each tower vehicle in the next state can be obtained in time information. The RTK base station 3 and the RTK mobile station 4 are also equipped with a wireless communication module, and when the positioning accuracy of the single-point positioning performed by the RTK base station 3 is on the order of submeters, the accuracy of the positioning data calculated by the RTK mobile station 4 is at the centimeter level. The positioning data of the whole device has high precision, and the data is obtained in real time, which greatly improves the timeliness and precision of system control.
[0033] Among them, the navigation controller 5 adopts an edge node method to calculate the positioning data, the actual operating frequency and rotation speed, and the tower span angle. During the working process, the navigation controller 5 only needs to send the calculated position information, speed information and heading information of each tower vehicle to the navigation system control unit 1 through the first wireless data transmission station 10 . The navigation system control unit 1 does not need to obtain the actual operating frequency and rotation speed of the variable frequency motor 7 and the tower span angle sensed by the tower span angle sensor 8 . At the same time, when the navigation system control unit 1 adjusts the movement of each tower truck, it only needs to send the speed information and heading information of the next state of the tower truck to realize the control of the tower truck.
[0034] Among them, the tower truck motion control unit 2 also includes an inertial navigation method. After losing the high-precision positioning data of the RTK mobile station, the tower truck can still continue to operate in a safe mode with a small tower span angle. The navigation controller 5 calculates the operating state (operating frequency and rotational speed) of the variable frequency motor, calculates the position, course and speed information of the tower truck, and sends it to the navigation system control unit 1 .
[0035] The real-time example of the present invention provides a synchronous walking control method, which is used to control the synchronous walking of multiple tower trucks of the sprinkler irrigation machine, including:
[0036] S1, the PTK base station 3 sends differential data to the PTK mobile station 4, and the PTK mobile station 4 obtains positioning data according to the differential data, and obtains its own antenna position data.
[0037] Wherein, the differential data is generated by the RTK base station 3 according to the received satellite ephemeris data, including differential ranging error, pseudorange correction data and other data. The differential data includes the current position information of each tower truck node. Before sending the differential data, the PTK base station 3 will establish a base station coordinate system according to its own position information.
[0038] S2, the tower span angle sensor 8 obtains the tower span angle of each tower car, and the variable frequency motor controller 6 obtains the actual operating frequency and rotational speed of the variable frequency motor 7 .
[0039] S3, the navigation controller 5 calculates the positioning data to obtain the current position information of each tower truck, calculates the tower span angle and the PTK dynamic station 4 dual-antenna position data to obtain the current heading information of each tower truck, and calculates the actual operating frequency and rotation speed to obtain the current speed of each tower truck information.
[0040] S4, the central processor 9 obtains the control parameters for the synchronous walking of each tower car in the next state according to the current position information, heading information, speed information of each tower car and the preset travel path of each tower car, and sends them to the variable frequency motor controller6.
[0041] Wherein, these control parameters include the speed information and heading information of each tower truck in the next state. In the process of obtaining the control parameters, the central processor 9 performs local coordinate conversion on the current position information of each tower truck according to the base station position coordinates, performs numerical fitting on the locally converted coordinates, and detects the straightness of each tower truck when it is traveling.
[0042] S5, the variable frequency motor controller 6 controls the variable frequency motor 7 according to the control parameters to drive each tower truck to move synchronously.
[0043] The variable frequency motor controller 6 adjusts the parameters of the variable frequency motor 7 (operating frequency, rotational speed, etc.) according to the control parameters, and realizes straightness correction and path navigation through differential steering. The mutual influence of vehicles and walking reduces the lateral error of the irrigation machine and improves the stability of the multi-tower vehicle of the irrigation machine.
[0044] Through the S1-S5 cycle operation, the position information, course information and speed information of each tower vehicle are obtained in real time, and the control parameters of each vehicle's motion posture in the next state are obtained in time, so as to realize the synchronous walking of the multi-tower vehicles of the sprinkler irrigation machine.
[0045] In summary, the embodiment of the present invention proposes a synchronous walking control device and method; the high-precision positioning data of each tower truck is obtained through the PTK base station and the PTK dynamic station, which greatly improves the control accuracy; the position of each tower truck is obtained in real time Information, course information and speed information, so as to obtain the walking course and speed of each tower vehicle in the next state in time, which greatly improves the timeliness of control; the straightness correction and path navigation are realized by means of differential steering, which reduces the number of sprinkling machines. The mutual influence of the traveling of the tower trucks reduces the lateral error of the sprinkler irrigation machine and improves the stability of the multi-tower trucks of the sprinkler irrigation machine.
[0046] The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.
