WO2021077306A1 - Procédé de commande de retour de véhicule aérien sans pilote, terminal utilisateur et véhicule aérien sans pilote - Google Patents

Procédé de commande de retour de véhicule aérien sans pilote, terminal utilisateur et véhicule aérien sans pilote Download PDF

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Publication number
WO2021077306A1
WO2021077306A1 PCT/CN2019/112613 CN2019112613W WO2021077306A1 WO 2021077306 A1 WO2021077306 A1 WO 2021077306A1 CN 2019112613 W CN2019112613 W CN 2019112613W WO 2021077306 A1 WO2021077306 A1 WO 2021077306A1
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WIPO (PCT)
Prior art keywords
user terminal
unmanned aerial
aerial vehicle
distance
terminal
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PCT/CN2019/112613
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English (en)
Chinese (zh)
Inventor
张志鹏
钱杰
朱磊
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深圳市大疆创新科技有限公司
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Application filed by 深圳市大疆创新科技有限公司 filed Critical 深圳市大疆创新科技有限公司
Priority to PCT/CN2019/112613 priority Critical patent/WO2021077306A1/fr
Priority to CN201980032942.9A priority patent/CN112154393A/zh
Publication of WO2021077306A1 publication Critical patent/WO2021077306A1/fr

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    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00—Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots
    • G05D1/10—Simultaneous control of position or course in three dimensions
    • G05D1/101—Simultaneous control of position or course in three dimensions specially adapted for aircraft

Definitions

  • This specification relates to the technical field of unmanned aerial vehicles, in particular to an unmanned aerial vehicle's return control method, user terminal and unmanned aerial vehicle.
  • the user During the flight of the unmanned aerial vehicle, the user sometimes leaves the take-off point of the unmanned aerial vehicle. At this time, it is necessary to use the new position of the user as the home point to dynamically refresh the unmanned aerial vehicle.
  • the user uses the GPS location of the user terminal, such as a mobile terminal or a remote control terminal, as the new home point.
  • the mobile terminal or remote control terminal GPS due to the large error of the mobile terminal or remote control terminal GPS, it is about 10m, and the mobile terminal or remote control terminal GPS is susceptible to interference And occlusion, the error further increases.
  • the dynamically refreshed home point may deviate from the user's location, resulting in an increased risk of losing the UAV when returning home.
  • this manual provides a return-to-home control method, user terminal, and unmanned aerial vehicle for unmanned aerial vehicles. It aims to solve the problem that the existing return-to-home control cannot distinguish inaccurate home-return points, which can easily lead to the loss of unmanned aerial vehicles when returning to home. problem.
  • this specification provides a return-to-home control method of an unmanned aerial vehicle, which is used in a user terminal, and the method includes:
  • the terminal position is sent to the unmanned aerial vehicle as a home point.
  • this specification provides a return-to-home control method of an unmanned aerial vehicle, which is used in an unmanned aerial vehicle, and the method includes:
  • the terminal position is determined as the home point of the UAV.
  • this specification provides a user terminal, including a memory and a processor
  • the memory is used to store a computer program
  • the processor is configured to execute the computer program and when executing the computer program, realize:
  • the terminal position is sent to the unmanned aerial vehicle as a home point.
  • this specification provides an unmanned aerial vehicle, including a memory and a processor
  • the memory is used to store a computer program
  • the processor is configured to execute the computer program and when executing the computer program, realize:
  • the terminal position is determined as the home point of the UAV.
  • this specification provides a computer-readable storage medium that stores a computer program, and when the computer program is executed by a processor, the processor implements the above-mentioned method.
  • the embodiments of this specification provide a return control method of an unmanned aerial vehicle, a user terminal, and an unmanned aerial vehicle.
  • the positioning distance is determined according to the terminal position of the user terminal and the flight position of the unmanned aerial vehicle, and the positioning distance is determined according to the difference between the user terminal and the unmanned aerial vehicle.
  • the delay information of inter-signal transmission determines the communication distance between the user terminal and the unmanned aerial vehicle; then judges whether the terminal position of the user terminal is accurate according to the higher-accuracy communication distance, and uses the accurate terminal position as the return point of the unmanned aerial vehicle , Can prevent the unmanned aerial vehicle from using the inaccurate terminal position as the home point, so as to ensure flight safety.
  • FIG. 1 is a schematic flowchart of a return-to-home control method of an unmanned aerial vehicle according to an embodiment of this specification
  • Figure 2 is a schematic diagram of communication between a user terminal and an unmanned aerial vehicle
  • FIG. 3 is a schematic flowchart of an embodiment of a return control method of an unmanned aerial vehicle
  • FIG. 4 is a schematic diagram of determining the communication position of the user terminal according to the flight position and the communication distance;
  • FIG. 5 is a schematic flowchart of a return control method of an unmanned aerial vehicle according to another embodiment of this specification.
  • FIG. 6 is a schematic flowchart of an embodiment of a return control method of an unmanned aerial vehicle
  • Fig. 7 is a schematic block diagram of a user terminal according to an embodiment of the present specification.
  • Fig. 8 is a schematic block diagram of an unmanned aerial vehicle according to an embodiment of the present specification.
  • FIG. 1 is a schematic flowchart of a return-to-home control method of an unmanned aerial vehicle according to an embodiment of this specification.
  • the return home control method can be applied to a user terminal, and is used for processes such as determining the return point of the unmanned aerial vehicle according to the location of the user terminal.
  • the user terminal may include at least one of a mobile terminal, a remote control terminal, and a wearable device.
  • Mobile terminals such as mobile phones, tablet computers, notebook computers, etc.
  • remote control terminals such as remote controllers of unmanned aerial vehicles, etc.
  • wearable devices such as FPV (First Person View, first-person view) glasses, VR (Virtual Reality, virtual reality) Glasses etc.
  • the unmanned aerial vehicle can be, for example, a rotary wing drone, such as a quadrotor drone, a hexarotor drone, an eight rotor drone, or a fixed wing drone.
  • a rotary wing drone such as a quadrotor drone, a hexarotor drone, an eight rotor drone, or a fixed wing drone.
  • the user terminal and the UAV communicate via a wireless channel.
  • the unmanned aerial vehicle can fly according to the control of the user terminal, or the unmanned aerial vehicle can fly autonomously.
  • the user carries the user terminal, and when the unmanned aerial vehicle needs to return home autonomously or according to the control of the user terminal, the unmanned aerial vehicle returns to the location where the user terminal is located.
  • the user terminal may display the position B of the unmanned aerial vehicle and the position A of the user terminal.
  • the return home control method of the unmanned aerial vehicle of this embodiment includes steps S110 to S140.
  • the user terminal is equipped with a positioning device, for example, the location of the user terminal can be determined through a navigation system.
  • the user terminal obtains the latitude and longitude of the user terminal determined by the positioning device mounted on the user terminal.
  • the unmanned aerial vehicle is also equipped with a positioning device, for example, the position of the unmanned aerial vehicle can be determined through a navigation system.
  • the user terminal may obtain the latitude and longitude of the unmanned aerial vehicle from the unmanned aerial vehicle, and the latitude and longitude of the unmanned aerial vehicle may be determined by a positioning device mounted on the unmanned aerial vehicle.
  • the user terminal periodically obtains the location of the terminal.
  • the user terminal periodically requests the unmanned aerial vehicle to obtain the flight position of the unmanned aerial vehicle.
  • the unmanned aerial vehicle sends the flight position to the user terminal according to the request of the user terminal.
  • the unmanned aerial vehicle periodically obtains the flight position, and sends the obtained flight position to the user terminal.
  • the terminal position of the user terminal is (x1, y1)
  • the flight position of the unmanned aerial vehicle is (x2, y2).
  • the determining the positioning distance according to the terminal position and the flight position includes: determining the positioning distance according to the longitude and latitude of the user terminal and the longitude and latitude of the unmanned aerial vehicle.
  • the positioning distance represents the distance between the projection of the terminal position of the user terminal and the flight position of the unmanned aerial vehicle on the same horizontal plane.
  • the positioning distance d can be expressed as:
  • the user uses an unmanned aerial vehicle
  • there is a certain distance between the unmanned aerial vehicle and the user terminal and it takes a certain time for the communication signal to be transmitted between the unmanned aerial vehicle and the user terminal.
  • the user terminal obtains the round-trip delay of signal transmission between the user terminal and the UAV.
  • the user terminal periodically sends a terminal signal to the unmanned aerial vehicle, and the unmanned aerial vehicle sends a feedback signal to the user terminal in response to the terminal signal sent by the user terminal.
  • the user terminal determines the signal transmission delay information with the UAV according to the time difference between sending the terminal signal and receiving the feedback signal.
  • the user terminal periodically requests the unmanned aerial vehicle to obtain the flight position of the unmanned aerial vehicle, and the unmanned aerial vehicle sends the flight position to the user terminal according to the request of the user terminal.
  • the user terminal determines the signal transmission delay information with the UAV according to the time difference between the sending request and the receiving flight position.
  • the user terminal may obtain signal transmission delay information from the UAV.
  • the unmanned aerial vehicle periodically sends a flight end signal to the user terminal, and the user terminal sends a feedback signal to the user terminal in response to the flight end signal sent by the unmanned aerial vehicle.
  • the unmanned aerial vehicle determines the delay information of signal transmission with the user terminal according to the time difference between sending the flight terminal signal and receiving the feedback signal, and then the unmanned aerial vehicle can send the delay information to the user terminal.
  • the signal transmission delay between the user terminal and the unmanned aerial vehicle includes the signal transmission time from the user terminal to the unmanned aerial vehicle and the signal transmission time from the unmanned aerial vehicle to the user terminal. Therefore, between the user terminal and the unmanned aerial vehicle
  • the delay information of signal transmission includes the round-trip time (Round-Trip Time, RTT) of signal transmission.
  • the user terminal determines the communication distance between the user terminal and the UAV according to the round-trip time delay.
  • the communication distance between the user terminal and the UAV is determined according to the transmission speed of the electromagnetic signal and the round-trip time delay.
  • the maximum error of the round-trip distance between the user terminal and the UAV determined by the round-trip time delay is the distance corresponding to 0.5 sampling points.
  • the maximum error of the communication distance between the user terminal and the UAV can be further reduced, so as to obtain a more accurate communication distance.
  • the obtaining the delay information of the signal transmission between the user terminal and the unmanned aerial vehicle includes: according to the time stamp carried by the signal between the user terminal and the unmanned aerial vehicle and receiving the information The time of the signal determines the delay information.
  • the flight position sent by the unmanned aerial vehicle to the user terminal has the time stamp of the time of sending
  • the user terminal can obtain the time when the unmanned aerial vehicle sends the flight position after receiving the flight position
  • the user terminal can determine the time when the flight position is received
  • the transmission time of the signal from the unmanned aerial vehicle to the user terminal can be obtained, and the communication distance between the user terminal and the unmanned aerial vehicle can be determined according to the transmission time.
  • the communication distance between the user terminal and the UAV determined by the time delay includes the distance error corresponding to the sampling point.
  • the return home control method further includes: adjusting the communication distance according to the distance error.
  • the distance error may be determined according to the sampling frequency of signal transmission between the user terminal and the UAV.
  • the sampling frequency fs is 30Msps
  • the communication distance can be adjusted according to the distance error, and the adjusted communication distance is D+ ⁇ or D- ⁇ .
  • the performance of the positioning device carried by the user terminal is lower, and the positioning accuracy is low; while the performance of the positioning device carried by the unmanned aerial vehicle is better than that of the positioning device carried by the user terminal, and the positioning accuracy is higher.
  • the user terminal is generally located at a low altitude and is easily blocked. Therefore, the accuracy of positioning is easily interfered by the blocking, causing drift or unable to refresh the position of the terminal in time; while the unmanned aerial vehicle is interfered by the blocking. The possibility is small, and the positioning accuracy is high.
  • the communication distance is the accurate calculation of the relative distance between the user terminal and the UAV by detecting the time interval between sending and receiving packets, it is possible to verify whether the terminal position of the user terminal is based on a more accurate communication distance. accurate.
  • the position range of the user terminal can be determined. If the terminal position of the user terminal exceeds this range, it can be considered that the terminal position is inaccurate, and the UAV may refuse to refresh the home point based on the terminal position and notify the user.
  • the terminal position is accurate; if the distance difference between the communication distance and the positioning distance is greater than all According to the deviation threshold, it is determined that the terminal position is not accurate.
  • the deviation threshold may be determined according to the flying height of the unmanned aerial vehicle, the flying speed of the unmanned aerial vehicle, and the like.
  • the judging whether the position of the terminal is accurate according to the positioning distance and the communication distance includes: determining the horizontal distance between the user terminal and the UAV according to the communication distance; Determine whether the position of the terminal is accurate according to the distance difference between the horizontal distance and the positioning distance.
  • the flying height of the unmanned aerial vehicle is relatively high, such as tens of meters or hundreds of meters, and it is necessary to determine whether the position of the terminal is accurate according to the horizontal distance corresponding to the communication distance.
  • the horizontal distance between the user terminal corresponding to the communication distance and the UAV may be determined by the communication distance.
  • the user terminal obtains the flying height of the unmanned aerial vehicle from the unmanned aerial vehicle, and determines the horizontal distance between the user terminal and the unmanned aerial vehicle according to the flying height and the communication distance .
  • the return-to-home control method of the unmanned aerial vehicle further includes: obtaining the flying height of the unmanned aerial vehicle.
  • the user terminal may obtain the flying height of the unmanned aerial vehicle from the unmanned aerial vehicle.
  • the flying height of the unmanned aerial vehicle is determined by a positioning device mounted on the unmanned aerial vehicle, or the unmanned aerial vehicle is determined by at least one of a barometer, an accelerometer, an ultrasonic sensor, and the like.
  • the altitude of the unmanned aerial vehicle may change during the flight, for example, the user controls the unmanned aerial vehicle to adjust the flying height through the user terminal.
  • the user terminal periodically requests the unmanned aerial vehicle to obtain the flying height of the unmanned aerial vehicle.
  • the unmanned aerial vehicle sends the flying height to the user terminal according to the request of the user terminal.
  • the unmanned aerial vehicle periodically obtains the flight altitude, and sends the obtained flight altitude to the user terminal. Therefore, the user terminal can obtain the real-time height of the unmanned aerial vehicle, and judge whether the position of the terminal is accurate according to the flying height of the unmanned aerial vehicle, the positioning distance, and the communication distance.
  • the horizontal distance between the user terminal and the unmanned aerial vehicle is: or
  • the determining the communication distance between the user terminal and the UAV according to the delay information in step S120 includes: determining the user according to the delay information and the flight height The horizontal distance between the terminal and the UAV. That is, the horizontal distance is regarded as the communication distance between the user terminal and the UAV.
  • the judging whether the terminal position is accurate according to the distance difference between the horizontal distance and the positioning distance includes: if the distance difference between the horizontal distance and the positioning distance is not greater than a preset difference If the distance between the horizontal distance and the positioning distance is greater than the difference threshold, it is determined that the terminal location is not accurate.
  • the preset upper limit of error is expressed as ⁇ , for example, ⁇ is 20 meters; the distance difference between the horizontal distance and the positioning distance is the absolute value of the difference between the horizontal distance and the positioning distance. If the distance difference is not greater than ⁇ , it is determined that the terminal position is accurate; if the distance difference is greater than ⁇ , it is determined that the terminal position is not accurate.
  • the difference threshold may be determined according to the flight speed of the unmanned aerial vehicle, the preset upper limit of error, and the like.
  • the total duration of the process of determining the flight position of the unmanned aerial vehicle and sending the flight position to the user terminal is t, for example, t is 50 milliseconds
  • the upper limit of the relative speed between the user and the unmanned aerial vehicle is v, for example, v is At 50 meters per second
  • the difference threshold can be determined as: ⁇ +v ⁇ t. It is possible to prevent a terminal position with a small deviation from being misjudged as an inaccurate position.
  • the user terminal determines the terminal position of the user terminal at a certain moment, such as (x1, y1) is accurate, the user terminal sends the terminal position and the mark used to indicate that the terminal position is the home point to the terminal. People flying machine.
  • the unmanned aerial vehicle determines the terminal position as the home point position according to the mark.
  • the unmanned aerial vehicle receives a return instruction sent by the user terminal, or when it returns autonomously, it executes the return task according to the return point received from the user terminal.
  • the user terminal periodically executes the above steps S110 to S140, and when determining that the terminal position of the current period is accurate, the terminal position is sent to the UAV as a new home point, so that the unmanned aerial vehicle The human aircraft updates the latest home point. In this way, the user's accurate new position is used as the home point and dynamically refreshed to the unmanned aerial vehicle. If the unmanned aerial vehicle receives the return instruction sent by the user terminal, or when it returns autonomously, it will return to the home according to the latest home point.
  • the return home control method further includes: if it is determined that the terminal position is inaccurate, sending out a prompt message for prompting the user that the return point has not been refreshed.
  • the terminal position of the user terminal is inaccurate in a certain period, the terminal position is not sent to the unmanned aerial vehicle as the home point, and the prompt information is output through visual or audio output.
  • the user can move to an open area to facilitate accurate positioning of the user terminal. Therefore, the subsequent unmanned aerial vehicle can return to the vicinity of the user accurately.
  • the return home control method further includes step S150 and step S160.
  • the at least one flight position is at least one position on the flight path of the unmanned aerial vehicle.
  • the user terminal can more accurately determine the position of the user terminal relative to the unmanned aerial vehicle.
  • the communication position of the user terminal is determined according to at least one flight position of the unmanned aerial vehicle and the communication distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least one flight position , Including: determining the communication position of the user terminal according to the at least one flight position of the unmanned aerial vehicle and the horizontal distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least one flight position.
  • the horizontal distance is determined based on the delay information between the user terminal and the unmanned aerial vehicle and the flying height of the unmanned aerial vehicle.
  • the unmanned aerial vehicle in a certain period of time, flies from the flight position 1 to the flight position 2, and then flies from the flight position 2 to the flight position 3.
  • the delay information determined by the user terminal is T1
  • the determined communication distance is L1
  • the delay information determined by the user terminal It is T2
  • the determined communication distance is L2
  • the UAV sends flight position 3 to the user terminal the delay information determined by the user terminal is T3, and the determined communication distance is L3.
  • the user terminal determines the communication distance of the user terminal according to the at least three flight positions of the UAV and the communication distance between the UAV and the user terminal when the UAV is in the at least three flight positions. Communication location.
  • FIG. 4 According to the coordinates of flight position 1, flight position 2, and flight position 3, as well as the communication distance L1 between the unmanned aerial vehicle and the user terminal in flight position 1, and the user terminal in flight position 2.
  • the communication distance L2 and the communication distance L4 with the user terminal at the flight position 3 determine an intersection point, and the coordinates of the intersection point are determined as the communication position of the user terminal.
  • the user terminal is based on at least one flight position of the unmanned aerial vehicle, and the communication distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least one flight position, and the position of the unmanned aerial vehicle At least one flight position determines the communication position of the user terminal relative to the direction of the user terminal.
  • the user terminal may determine the direction of the unmanned aerial vehicle relative to the user terminal according to the transmitted signal during signal transmission between the user terminal and the unmanned aerial vehicle.
  • the user terminal can detect the receiving angle of the signal received from the unmanned aerial vehicle, so that the direction of the unmanned aerial vehicle relative to the user terminal can be determined.
  • the communication position of the user terminal is determined according to the flying position of the unmanned aerial vehicle and the communication distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the flying position.
  • the flight position of the unmanned aerial vehicle Since the flight position of the unmanned aerial vehicle has sufficient accuracy, and the accuracy of the communication distance determined according to the communication delay is also high, it can be based on the flight position of the unmanned aerial vehicle when the terminal position determined by the user terminal according to the positioning device is not accurate.
  • the communication distance between the unmanned aerial vehicle and the user terminal when it is in the flight position can more accurately determine the communication position of the user terminal.
  • the unmanned aerial vehicle can have more opportunities to refresh the home point and maintain the accuracy of the home point. Avoid refreshing the home point where the position offset is too large to ensure flight safety.
  • the return-to-home control method of the unmanned aerial vehicle determines the positioning distance through the terminal position of the user terminal and the flight position of the unmanned aerial vehicle, and determines the location based on the delay information of the signal transmission between the user terminal and the unmanned aerial vehicle.
  • the communication distance between the user terminal and the unmanned aerial vehicle then judge whether the terminal position of the user terminal is accurate according to the communication distance with higher accuracy, and send the accurate terminal position to the unmanned aerial vehicle as the return of the unmanned aerial vehicle It can prevent the unmanned aerial vehicle from using the inaccurate terminal position as the home point, thereby ensuring flight safety.
  • FIG. 5 is a schematic flowchart of a return-to-home control method of an unmanned aerial vehicle according to another embodiment of the present application.
  • the return home control method can be applied to unmanned aerial vehicles, and is used for processes such as determining the homeward point of the unmanned aerial vehicle according to the position of the user terminal.
  • the user terminal may include at least one of a mobile terminal, a remote control terminal, and a wearable device.
  • Mobile terminals such as mobile phones, tablet computers, notebook computers, etc.
  • remote control terminals such as remote controllers of unmanned aerial vehicles, etc.
  • wearable devices such as FPV (First Person View, first-person view) glasses, VR (Virtual Reality, virtual reality) Glasses etc.
  • the unmanned aerial vehicle can be, for example, a rotary wing drone, such as a quadrotor drone, a hexarotor drone, an eight rotor drone, or a fixed wing drone.
  • a rotary wing drone such as a quadrotor drone, a hexarotor drone, an eight rotor drone, or a fixed wing drone.
  • the return-to-home control method of the unmanned aerial vehicle of this embodiment includes steps S210 to S240.
  • the execution sequence of the steps of obtaining the terminal position, obtaining the flight position, and determining the positioning distance is not limited.
  • the flight position may be acquired first and then the terminal position may be acquired, or the flight position may be acquired multiple times after the terminal position is acquired in a certain time, and the positioning distance corresponding to each flight position may be determined.
  • the unmanned aerial vehicle is equipped with a positioning device, for example, the position of the unmanned aerial vehicle can be determined through a navigation system.
  • the unmanned aerial vehicle obtains the latitude and longitude of the unmanned aerial vehicle determined by the positioning device mounted on the unmanned aerial vehicle.
  • the user terminal is also equipped with a positioning device, for example, the location of the user terminal can be determined through a navigation system.
  • the unmanned aerial vehicle may obtain the latitude and longitude of the user terminal from the user terminal, and the latitude and longitude of the user terminal is determined by a positioning device mounted on the user terminal.
  • the unmanned aerial vehicle periodically obtains the flight position.
  • the unmanned aerial vehicle periodically requests the user terminal to obtain the terminal position of the user terminal.
  • the user terminal sends the terminal position to the unmanned aerial vehicle according to the request of the unmanned aerial vehicle.
  • the user terminal periodically obtains the terminal position, and sends the obtained terminal position to the unmanned aerial vehicle.
  • the flight position of the unmanned aerial vehicle is (x1, y1)
  • the terminal position of the user terminal is (x2, y2).
  • the determining the positioning distance according to the terminal position and the flight position includes: determining the positioning distance according to the longitude and latitude of the user terminal and the longitude and latitude of the unmanned aerial vehicle.
  • the positioning distance represents the distance between the flight position of the unmanned aerial vehicle and the projection of the terminal position of the user terminal on the same horizontal plane.
  • the positioning distance d can be expressed as:
  • S220 Acquire delay information of signal transmission between the user terminal and the UAV, and determine the communication distance between the user terminal and the UAV according to the delay information.
  • the user uses an unmanned aerial vehicle
  • there is a certain distance between the unmanned aerial vehicle and the user terminal and it takes a certain time for the communication signal to be transmitted between the unmanned aerial vehicle and the user terminal.
  • the unmanned aerial vehicle acquires the round-trip delay of signal transmission between the UAV and the user terminal.
  • the unmanned aerial vehicle periodically sends a flight end signal to the user terminal, and the user terminal sends a feedback signal to the unmanned aerial vehicle in response to the flight end signal sent by the unmanned aerial vehicle.
  • the unmanned aerial vehicle determines the signal transmission delay information with the user terminal according to the time difference between sending the flight terminal signal and receiving the feedback signal.
  • the unmanned aerial vehicle periodically requests the user terminal to obtain the terminal position of the user terminal, and the user terminal sends the terminal position to the unmanned aerial vehicle according to the request of the unmanned aerial vehicle.
  • the unmanned aerial vehicle determines the signal transmission delay information with the user terminal according to the time difference between the sending request and the receiving terminal position.
  • the UAV can obtain signal transmission delay information from the user terminal.
  • the user terminal periodically sends a terminal signal to the unmanned aerial vehicle, and the unmanned aerial vehicle sends a feedback signal to the unmanned aerial vehicle in response to the terminal signal sent by the user terminal.
  • the user terminal determines the delay information of the signal transmission with the UAV according to the time difference between sending the terminal signal and receiving the feedback signal, and then the user terminal may send the delay information to the UAV.
  • the signal transmission delay between the user terminal and the unmanned aerial vehicle includes the signal transmission time from the unmanned aerial vehicle to the user terminal and the signal transmission time from the user terminal to the unmanned aerial vehicle.
  • the delay information of signal transmission includes the round-trip time (Round-Trip Time, RTT) of signal transmission.
  • the unmanned aerial vehicle determines the communication distance between the user terminal and the unmanned aerial vehicle according to the round-trip time delay.
  • the communication distance between the user terminal and the UAV is determined according to the transmission speed of the electromagnetic signal and the round-trip time delay.
  • the maximum error of the round-trip distance between the user terminal and the UAV determined by the round-trip time delay is the distance corresponding to 0.5 sampling points.
  • the maximum error of the communication distance between the user terminal and the UAV can be further reduced, so as to obtain a more accurate communication distance.
  • the obtaining the delay information of the signal transmission between the user terminal and the unmanned aerial vehicle includes: according to the time stamp carried by the signal between the user terminal and the unmanned aerial vehicle and receiving the information The time of the signal determines the delay information.
  • the terminal position sent by the user terminal to the unmanned aerial vehicle has a time stamp when the terminal was sent, and the unmanned aerial vehicle can obtain the time when the terminal position is sent by the user terminal after receiving the terminal position, and the unmanned aerial vehicle can determine to receive the terminal position. Therefore, the transmission time of the signal from the user terminal to the UAV can be obtained, and the communication distance between the user terminal and the UAV can be determined according to the transmission time.
  • the communication distance between the user terminal and the UAV determined by the time delay includes the distance error corresponding to the sampling point.
  • the return home control method further includes: adjusting the communication distance according to the distance error.
  • the distance error may be determined according to the sampling frequency of signal transmission between the user terminal and the UAV.
  • the sampling frequency fs is 30Msps
  • the communication distance can be adjusted according to the distance error, and the adjusted communication distance is D+ ⁇ or D- ⁇ .
  • S230 Determine whether the position of the terminal is accurate according to the positioning distance and the communication distance.
  • the performance of the positioning device carried by the user terminal is lower, and the positioning accuracy is low; while the performance of the positioning device carried by the unmanned aerial vehicle is better than that of the positioning device carried by the user terminal, and the positioning accuracy is higher.
  • the user terminal is generally located at a low altitude and is easily blocked. Therefore, the accuracy of positioning is easily interfered by the blocking, causing drift or unable to refresh the position of the terminal in time; while the unmanned aerial vehicle is interfered by the blocking. The possibility is small, and the positioning accuracy is high.
  • the communication distance is the accurate calculation of the relative distance between the user terminal and the UAV by detecting the time interval between sending and receiving packets, it is possible to verify whether the terminal position of the user terminal is based on a more accurate communication distance. accurate.
  • the position range of the user terminal can be determined. If the terminal position of the user terminal exceeds this range, it can be considered that the terminal position is inaccurate, and the UAV may refuse to refresh the home point based on the terminal position and notify the user.
  • the terminal position is accurate; if the distance difference between the communication distance and the positioning distance is If it is greater than the deviation threshold, it is determined that the terminal position is not accurate.
  • the deviation threshold may be determined according to the flying height of the unmanned aerial vehicle, the flying speed of the unmanned aerial vehicle, and the like.
  • the judging whether the position of the terminal is accurate according to the positioning distance and the communication distance includes: determining the horizontal distance between the user terminal and the UAV according to the communication distance; Determine whether the position of the terminal is accurate according to the distance difference between the horizontal distance and the positioning distance.
  • the flying height of the unmanned aerial vehicle is relatively high, such as tens of meters or hundreds of meters, and it is necessary to determine whether the position of the terminal is accurate according to the horizontal distance corresponding to the communication distance.
  • the horizontal distance between the user terminal corresponding to the communication distance and the UAV may be determined by the communication distance.
  • the unmanned aerial vehicle obtains the flying height of the unmanned aerial vehicle, and determines the horizontal distance between the user terminal and the unmanned aerial vehicle according to the flying height and the communication distance.
  • the return-to-home control method of the unmanned aerial vehicle further includes: obtaining the flying height of the unmanned aerial vehicle.
  • the unmanned aerial vehicle periodically obtains the flying height of the unmanned aerial vehicle.
  • the flying height of the unmanned aerial vehicle is determined by a positioning device mounted on the unmanned aerial vehicle, or the unmanned aerial vehicle is determined by at least one of a barometer, an accelerometer, an ultrasonic sensor, and the like.
  • the altitude of the unmanned aerial vehicle may change during the flight, for example, the user controls the unmanned aerial vehicle to adjust the flying height through the user terminal.
  • the unmanned aerial vehicle periodically obtains the flight altitude, can obtain the real-time altitude of the unmanned aerial vehicle, and judges whether the terminal position is accurate according to the flight altitude of the unmanned aerial vehicle, the positioning distance, and the communication distance.
  • the horizontal distance between the user terminal and the unmanned aerial vehicle is: or
  • the determining the communication distance between the user terminal and the UAV according to the delay information in step S220 includes: determining the user according to the delay information and the flight height The horizontal distance between the terminal and the UAV. That is, the horizontal distance is regarded as the communication distance between the user terminal and the UAV.
  • the judging whether the terminal position is accurate according to the distance difference between the horizontal distance and the positioning distance includes: if the distance difference between the horizontal distance and the positioning distance is not greater than a preset difference If the distance between the horizontal distance and the positioning distance is greater than the difference threshold, it is determined that the terminal location is not accurate.
  • the preset upper limit of error is expressed as ⁇ , for example, ⁇ is 20 meters; the distance difference between the horizontal distance and the positioning distance is the absolute value of the difference between the horizontal distance and the positioning distance. If the distance difference is not greater than ⁇ , it is determined that the terminal position is accurate; if the distance difference is greater than ⁇ , it is determined that the terminal position is not accurate.
  • the difference threshold may be determined according to the flight speed of the unmanned aerial vehicle, the preset upper limit of error, and the like.
  • the total duration of the process of determining the terminal position and sending the terminal position to the unmanned aerial vehicle by the user terminal is t, for example, t is 50 milliseconds
  • the upper limit of the relative speed between the user and the unmanned aerial vehicle is v, for example, v is At 50 meters per second
  • the difference threshold can be determined as: ⁇ +v ⁇ t.
  • the unmanned aerial vehicle determines that the terminal position sent by the user terminal at a certain moment, such as (x1, y1) is accurate, the unmanned aerial vehicle determines the terminal position as the position of the home point.
  • the unmanned aerial vehicle receives a return instruction sent by the user terminal, or when it returns autonomously, it executes the return task according to the terminal position determined as the return point.
  • the unmanned aerial vehicle periodically executes the above-mentioned steps S210 to S240, and when it is determined that the terminal position of the current period is accurate, the terminal position is used as the new homeward point, so that the unmanned aerial vehicle updates the latest homeward return. point. In this way, the accurate new position of the user can be used as the new home point of the unmanned aerial vehicle.
  • the home point is sent to the user terminal, so that the user terminal displays the home point. Therefore, the user can accurately understand the current position relative to the unmanned aerial vehicle.
  • the return home control method further includes: if it is determined that the terminal position is not accurate, sending an error notification to the user terminal, so that the user terminal prompts the user that the home return point has not been updated according to the error notification.
  • the unmanned aerial vehicle determines that the terminal position of the user terminal is inaccurate in a certain period, the terminal position is not used as the homeward point, and an error notification is sent to the user terminal, so that the user terminal is based on the Error notification, prompt information through visual output or audio output.
  • the user can move to an open area to facilitate accurate positioning of the user terminal. Therefore, the subsequent unmanned aerial vehicle can return to the vicinity of the user accurately.
  • the return home control method further includes step S250.
  • the at least one flight position is at least one position on the flight path of the unmanned aerial vehicle.
  • the user terminal can more accurately determine the position of the user terminal relative to the unmanned aerial vehicle.
  • the communication position of the user terminal is determined according to at least one flight position of the unmanned aerial vehicle and the communication distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least one flight position , Including: determining the communication position of the user terminal according to the at least one flight position of the unmanned aerial vehicle and the horizontal distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least one flight position.
  • the horizontal distance is determined according to the delay information between the user terminal and the unmanned aerial vehicle and the flying height of the unmanned aerial vehicle.
  • the unmanned aerial vehicle determines the communication position of the user terminal according to at least three flight positions and the communication distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least three flight positions.
  • the unmanned aerial vehicle is based on the coordinates of flight position 1, flight position 2, and flight position 3, as well as the communication distance L1 between the unmanned aerial vehicle and the user terminal when it is in flight position 1, and when it is in flight position 2.
  • the communication distance L2 with the user terminal and the communication distance L4 with the user terminal at the flight position 3 determine an intersection, and the coordinates of the intersection are determined as the communication position of the user terminal.
  • the user terminal is based on at least one flight position of the unmanned aerial vehicle, and the communication distance between the unmanned aerial vehicle and the user terminal when the unmanned aerial vehicle is in the at least one flight position, and the position of the unmanned aerial vehicle At least one flight position determines the communication position of the user terminal relative to the direction of the user terminal.
  • the unmanned aerial vehicle may determine the direction of the user terminal relative to the unmanned aerial vehicle according to the transmitted signal during signal transmission between the unmanned aerial vehicle and the user terminal.
  • the unmanned aerial vehicle can detect the receiving angle of the signal received from the user terminal, so that the direction of the user terminal relative to the unmanned aerial vehicle can be determined.
  • the unmanned aerial vehicle can be based on the unmanned aerial vehicle when the terminal position determined by the user terminal according to the positioning device is inaccurate.
  • the flight position and the communication distance between the UAV and the user terminal when the UAV is in the flight position can more accurately determine the communication position of the user terminal.
  • the unmanned aerial vehicle determines the communication position of the user terminal and uses the communication position as the home point, so that the unmanned aerial vehicle can have more opportunities to refresh the home point, and can maintain The accuracy of the home point avoids refreshing the home point that has a large offset to ensure flight safety.
  • the return-to-home control method of the unmanned aerial vehicle determines the positioning distance according to the terminal position of the user terminal and the flight position of the unmanned aerial vehicle, and determines the user terminal and the unmanned aerial vehicle according to the delay information of the signal transmission between the user terminal and the unmanned aerial vehicle.
  • the communication distance between unmanned aerial vehicles then judge whether the terminal position of the user terminal is accurate according to the communication distance with higher accuracy, and use the accurate terminal position as the home point of the unmanned aerial vehicle, which can prevent the unmanned aerial vehicle from becoming inaccurate
  • the terminal position is used as the home point to ensure flight safety.
  • FIG. 7 is a schematic block diagram of a user terminal 600 according to an embodiment of the present specification.
  • the user terminal 600 includes a processor 601 and a memory 602.
  • the processor 601 and the memory 602 are connected by a bus 603, and the bus 603 is, for example, an I2C (Inter-integrated Circuit) bus.
  • I2C Inter-integrated Circuit
  • the processor 601 may be a micro-controller unit (MCU), a central processing unit (CPU), a digital signal processor (Digital Signal Processor, DSP), or the like.
  • MCU micro-controller unit
  • CPU central processing unit
  • DSP Digital Signal Processor
  • the memory 602 may be a Flash chip, a read-only memory (ROM, Read-Only Memory) disk, an optical disk, a U disk, or a mobile hard disk.
  • the processor 601 is configured to run a computer program stored in the memory 602, and when executing the computer program, implement the aforementioned return control method for the unmanned aerial vehicle of the user terminal.
  • the processor 601 is configured to run a computer program stored in the memory 602, and implement the following steps when the computer program is executed:
  • the terminal position is sent to the unmanned aerial vehicle as a home point.
  • the embodiments of this specification also provide a computer-readable storage medium, the computer-readable storage medium stores a computer program, the computer program includes program instructions, and the processor executes the program instructions to implement the foregoing implementation
  • This example provides the steps of the return-to-home control method of the unmanned aerial vehicle used in the user terminal.
  • the computer-readable storage medium may be the internal storage unit of the user terminal described in any of the foregoing embodiments, such as the hard disk or memory of the user terminal.
  • the computer-readable storage medium may also be an external storage device of the user terminal, such as a plug-in hard disk equipped on the user terminal, a smart memory card (Smart Media Card, SMC), and a Secure Digital (SD) ) Card, Flash Card, etc.
  • a plug-in hard disk equipped on the user terminal such as a smart memory card (Smart Media Card, SMC), and a Secure Digital (SD) ) Card, Flash Card, etc.
  • SD Secure Digital
  • FIG. 8 is a schematic block diagram of an unmanned aerial vehicle 700 according to an embodiment of this specification.
  • the unmanned aerial vehicle 700 includes a processor 701 and a memory 702.
  • the processor 701 and the memory 702 are connected by a bus 703, and the bus 703 is, for example, an I2C (Inter-integrated Circuit) bus.
  • I2C Inter-integrated Circuit
  • the processor 701 may be a micro-controller unit (MCU), a central processing unit (CPU), a digital signal processor (Digital Signal Processor, DSP), or the like.
  • MCU micro-controller unit
  • CPU central processing unit
  • DSP Digital Signal Processor
  • the memory 702 may be a Flash chip, a read-only memory (ROM, Read-Only Memory) disk, an optical disk, a U disk, or a mobile hard disk.
  • the processor 701 is used to run a computer program stored in the memory 702, and when executing the computer program, implement the aforementioned return-to-home control method for an unmanned aerial vehicle.
  • the processor 701 is configured to run a computer program stored in the memory 702, and implement the following steps when the computer program is executed:
  • the terminal position is determined as the home point of the UAV.
  • the embodiments of this specification also provide a computer-readable storage medium, the computer-readable storage medium stores a computer program, the computer program includes program instructions, and the processor executes the program instructions to implement the foregoing implementation
  • This example provides the steps of the return-to-home control method for unmanned aerial vehicles.
  • the computer-readable storage medium may be the internal storage unit of the unmanned aerial vehicle described in any of the foregoing embodiments, such as the hard disk or memory of the unmanned aerial vehicle.
  • the computer-readable storage medium may also be an external storage device of the UAV, such as a plug-in hard disk equipped on the UAV, a Smart Media Card (SMC), or Secure Digital (Secure Digital). , SD) card, flash card (Flash Card), etc.
  • the user terminal, unmanned aerial vehicle, and computer-readable storage medium provided by the foregoing embodiments of this specification determine the positioning distance according to the terminal position of the user terminal and the flight position of the unmanned aerial vehicle, and according to the signal transmission between the user terminal and the unmanned aerial vehicle
  • the delay information determines the communication distance between the user terminal and the unmanned aerial vehicle; then judges whether the terminal position of the user terminal is accurate according to the communication distance with higher accuracy, and uses the accurate terminal position as the return point of the unmanned aerial vehicle to avoid The unmanned aerial vehicle uses the inaccurate terminal position as the homeward point, so as to ensure flight safety.

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Traffic Control Systems (AREA)

Abstract

Procédé de commande de retour d'un véhicule aérien sans pilote, terminal utilisateur et véhicule aérien sans pilote. Le procédé consiste à : déterminer une distance de positionnement entre le terminal utilisateur et le véhicule aérien sans pilote en fonction d'une position du terminal et d'une position de vol (S110); obtenir des informations de retard de transmission de signal entre le terminal utilisateur et le véhicule aérien sans pilote, et déterminer une distance de communication en fonction des informations de retard (S120); déterminer si la position du terminal est précise en fonction de la distance de positionnement et de la distance de communication (S130); et s'il est déterminé que la position du terminal est précise, utiliser la position du terminal comme point de retour (S140).
PCT/CN2019/112613 2019-10-22 2019-10-22 Procédé de commande de retour de véhicule aérien sans pilote, terminal utilisateur et véhicule aérien sans pilote WO2021077306A1 (fr)

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PCT/CN2019/112613 WO2021077306A1 (fr) 2019-10-22 2019-10-22 Procédé de commande de retour de véhicule aérien sans pilote, terminal utilisateur et véhicule aérien sans pilote
CN201980032942.9A CN112154393A (zh) 2019-10-22 2019-10-22 无人飞行器的返航控制方法、用户终端以及无人飞行器

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CN114035600A (zh) * 2021-11-30 2022-02-11 深圳市道通智能航空技术股份有限公司 一种无人飞行器监控方法、终端以及可读存储介质

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