CN108820222B - Ball-borne solar UAV launch control method - Google Patents

Abstract

The present disclosure provides a method for controlling the launch of a ball-mounted solar-powered unmanned aerial vehicle. Attitude control is performed through a pitch channel, a roll channel and a heading channel, starting from the working time of the cutter to the end of the drone body entering the cruising flight. The pitch angle of the UAV body gradually increases from vertical to downward until it meets the cruise flight conditions. The ball-mounted solar drone delivery control method provided by the present disclosure aims at the control logic problem of the roll channel, pitch channel and heading channel in the process of the ball-mounted solar drone being launched to the level flight of the ball-mounted solar drone. And the problem of when the three control channels are involved provides a feasible control scheme. The control method is closely integrated with engineering practice, can solve the problem of zero-speed delivery drone control method, and has strong engineering application value.

Description

Ball-borne solar UAV launch control method

technical field

The present disclosure relates to the technical field of unmanned aerial vehicle control, in particular to a method for controlling the launch of a ball-mounted solar-powered unmanned aerial vehicle.

Background technique

Near-space solar-powered UAVs have the characteristics of long cruising time and can fly across day and night or even across the week. At the same time, their flying height is high. With the continuous progress of energy storage battery technology, they have broad development prospects. At present, the way of solar-powered UAV entering the near space is mainly relying on the runway to climb autonomously, and the UAV climbs to the predetermined cruising altitude by its own power device. This method has relatively high requirements on the motor performance of the UAV; in addition, the UAV The influence of the climbing process needs to be considered in the design.

In view of this, a new method of solar drones entering the near space is designed. This method combines solar drones with high-altitude balloons for the first time, and uses the high-altitude aerostat platform to carry the solar drones to a designated height and then launch them to Entering the adjacent space, this method only needs to consider the cruise state requirements when designing an independent system. At the same time, the aerodynamic design of the UAV takes the cruise flight height as the reference design point, which has higher cruise performance, reduces the weight of the body itself, and increases the load capacity.

However, in the process of realizing the present disclosure, the inventors of the present application found that the adoption of the near-space ball-borne delivery method puts forward high requirements on the delivery method of the solar-powered UAV. Light and flexible, it puts forward high requirements for the overload during the delivery process; on the other hand, the delivery process time is short, and the flying state of the ball-mounted solar drone changes greatly, and it needs to complete the vertical zero initial speed state to the horizontal cruise in a short time. The flight state process is converted, so the existing delivery method cannot meet the requirements.

public content

(1) Technical problems to be solved

Based on the above technical problems, the present disclosure provides a method for controlling the launch of a ball-mounted solar-powered UAV, so as to alleviate the technical problem that the launch method in the prior art cannot meet the overload requirements and launch time of the solar-powered UAV.

(2) Technical solutions

The present disclosure provides a method for controlling the launch of a ball-borne solar-powered UAV. Attitude control is performed through a pitch channel, a roll channel and a heading channel. The ball-borne solar-powered UAV includes: an UAV body; a high-altitude balloon, and an UAV The body is connected by a rope; and a cutter is used to cut off the rope between the high-altitude balloon and the drone body; from the working time of the cutter to the end of the drone body entering the cruising flight, the ball-mounted solar-powered drone is put into control Methods include:

Step A: After the cutter works, pull up through the pitch channel, maintain the zero position in the roll channel, and stabilize the heading channel, so that the drone body reaches the first pitch angle;

Step B: The UAV body is made to reach the second pitch angle from the first pitch angle by performing zero position control and stabilization of the heading channel through the pitch channel pull-up, the roll angle of the roll channel and the stabilization of the heading channel;

Step C: Pull up the pitch channel, perform zero position control on the roll angle of the roll channel, and stabilize the heading channel, so that the drone body can reach the third pitch angle from the second pitch angle; and

Step D: after the drone body reaches the third pitch angle, when the drone body meets the cruise flight state criterion, the drone body starts to enter the cruise flight, and the delivery control process ends;

Wherein, the first pitch angle, the second pitch angle and the third pitch angle are the angles between the axis of the drone body and the horizontal plane, the first pitch angle, the second pitch angle and the third pitch angle are both between -90° and 0° and increase sequentially.

In some embodiments of the present disclosure, the first pitch angle is -70°, the second pitch angle is -50°, and the third pitch angle is -20°.

In some embodiments of the present disclosure, the pitch angle of the drone body at the initial moment of launch is -90°, and the direction of the heading angle of the drone body during the pull-up process is the drone-controlled flight 's heading.

In some embodiments of the present disclosure, before the working time of the cutter, the pitch channel controls the elevator deflection angle of the drone body to maintain a negative value.

In some embodiments of the present disclosure, in the step A and the step B, the pitch channel controls the elevator deflection angle to be the angle maintained before the cutter works.

In some embodiments of the present disclosure, in the step C, the pitch channel controls the elevator declination angle in real time, so that the UAV body is located at the pitch angle position calculated by the optimal track tracking under the premise of minimum acceleration .

In some embodiments of the present disclosure, the working moment of the cutter is the moment when the initial conditions of the drone body meet the launch requirements; wherein the launch requirements include: the three-axis of the spherical solar drone The attitude angular rate is less than ±5°/s, and the wind speed is less than 2m/s.

In some embodiments of the present disclosure, the step D includes: step D1: if the cruise flight state criterion is satisfied, enter the cruise flight; step D2: if the cruise flight state criterion is not satisfied, maintain the control of the third stage mode until the drone body satisfies the cruise flight state criterion.

In some embodiments of the present disclosure, the cruise flight state criterion includes: the flight airspeed of the drone body is greater than the stall speed; the pitch angle of the drone body is within ±3°; The pitch rate of the man-machine body is between ±10°/s.

In some embodiments of the present disclosure, the ball-borne solar-powered UAV further includes: fiber-optic inertial navigation, which is connected to the control module in the UAV body, and is used to give a control start time when the cutter is working.

(3) Beneficial effects

It can be seen from the above technical solutions that the ball-mounted solar-powered UAV launch control method provided by the present disclosure has one or a part of the following beneficial effects:

(1) The ball-mounted solar-powered UAV launch control method provided by the present disclosure is aimed at the control of the roll channel, pitch channel and heading channel in the process of the ball-mounted solar-powered UAV turning to level flight after the ball-mounted solar-powered UAV is launched. The logic problem and the question of when the three control channels are involved provide a feasible control scheme. This control method is closely integrated with engineering practice, and can solve the problem of zero-speed delivery drone control methods, which has strong engineering applications. value;

(2) Before the cutter (used to cut off the rope for suspending the ball-mounted solar drone), the lift angle of the drone is controlled at a negative value. After the cutter works, the drone has a head-up moment, so that Avoid the vertical axis of the drone entering a state of less than -90°, causing risks;

(3) In the first stage of launching and pulling, only the longitudinal channel is controlled to be pulled up, the roll channel is maintained, and the heading is controlled to increase stability, so that the lateral heading is stable, and the longitudinal direction is still controlled by the fixed rudder deflection angle, which can be controlled as much as possible. Reduce risk during pull-up.

Description of drawings

FIG. 1 is a schematic structural diagram of a spherical solar unmanned aerial vehicle provided by an embodiment of the present disclosure.

FIG. 2 is a schematic flowchart of a method for controlling the launch of a ball-mounted solar-powered UAV according to an embodiment of the present disclosure.

FIG. 3 is a logical structural diagram of a method for controlling the launch of a ball-mounted solar-powered UAV according to an embodiment of the present disclosure.

Detailed ways

The ball-mounted solar drone delivery control method provided by the embodiment of the present disclosure is aimed at the control logic of the roll channel, pitch channel and heading channel during the process of the ball-mounted solar drone being launched to the level flight of the ball-mounted solar drone problem, and the question of when the three control channels intervene provides a feasible control scheme, so that the launch process of the spherical solar UAV can proceed smoothly.

In order to make the objectives, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below with reference to the specific embodiments and the accompanying drawings.

The present disclosure provides a method for controlling the launch of a ball-borne solar-powered UAV. Attitude control is performed through a pitch channel, a roll channel and a heading channel. As shown in FIG. 1 , the ball-borne solar-powered UAV includes: a drone body; a high altitude The balloon is connected to the drone body by a rope; and the cutter is used to cut the rope between the high-altitude balloon and the drone body.

In some embodiments of the present disclosure, as shown in FIG. 2 , starting from the working time of the cutter and ending when the drone body enters the cruising flight, the ball-borne solar drone launch control method includes: Step A: the cutter After working, pull up the pitch channel, keep the roll channel at zero position, and stabilize the heading channel, so that the drone body reaches the first pitch angle; Step B: Control the zero position by pulling up the pitch channel and the roll angle of the roll channel And the heading channel is stabilized, so that the drone body can reach the second pitch angle from the first pitch angle; Step C: Pull up through the pitch channel, perform zero position control on the roll angle of the roll channel, and stabilize the heading channel to make the drone The body reaches the third pitch angle from the second pitch angle; and Step D: after the drone body reaches the third pitch angle, when the drone body meets the cruise flight state criterion, it starts to enter the cruise flight, and the delivery control process ends; wherein , the first pitch angle, the second pitch angle and the third pitch angle are the angles between the axis of the drone body and the horizontal plane, and the first pitch angle, the second pitch angle and the third pitch angle are all between -90° to 0 between ° and increasing in sequence, the ball-mounted solar drone delivery control method provided by the present disclosure is aimed at the roll channel, pitch channel and The control logic problem of the heading channel and the question of when the three control channels are involved provide a feasible control scheme. The control method is closely integrated with the engineering practice and can solve the problem of the control method of the zero-speed delivery UAV. Strong engineering application value.

为-70°，第二俯仰角

为-50°，第三俯仰角

为-20°。In some embodiments of the present disclosure, as shown in FIG. 1 , the first pitch angle

-70°, the second pitch angle

-50°, the third pitch angle

is -20°.

In some embodiments of the present disclosure, the nose of the ball-mounted solar-powered UAV is down at the initial time of launch, the normal direction of the UAV can be any direction, the pitch angle of the drone body at the initial time of launch is -90°, and the body of the UAV is -90°. The projection of the vertical axis on the horizontal plane is a point, and the heading angle of the drone body may be in any direction during the pull-up process, which is the heading of the drone controlled flight.

In some embodiments of the present disclosure, before the cutter works, as shown in FIG. 3 , the pitch channel controls the elevator declination angle of the drone body to maintain a negative value. After the cutter works, the drone is ready to head up. moment, so as to prevent the longitudinal axis of the drone from entering a state of less than -90°, causing risks.

In some embodiments of the present disclosure, in step A and step B, as shown in FIG. 3 , the pitch channel controls the elevator declination angle to be the angle maintained before the cutter working time, so as to reduce the difficulty of control during the pull-up process , thereby reducing the risk.

In some embodiments of the present disclosure, in step C, as shown in FIG. 3 , the pitch channel controls the elevator declination angle in real time, so that the drone body is located at the pitch angle position calculated by the optimal track tracking under the premise of minimum acceleration , that is, within the allowable overload range of the UAV body strength and the allowable range of the angle of attack, through the optimal track tracking calculation method, the pitch angle that can make the UAV body withstand the minimum acceleration is calculated. At present, the commonly used optimal track tracking calculation methods include the track tracking calculation method based on overload control, and the track tracking calculation method that gives a fixed target pitch angle and performs angular rate limiting at the same time.

In some embodiments of the present disclosure, as shown in FIG. 3 , the working moment of the cutter is the moment when the initial conditions of the drone body meet the delivery requirements.

In some embodiments of the present disclosure, the delivery requirements include: the three-axis attitude angular rate of the drone body is less than ±5°/s; and the wind speed is less than 2m/s.

In some embodiments of the present disclosure, as shown in FIG. 3 , step D includes: step D1: if the cruise flight state criterion is satisfied, enter the cruise flight; step D2: if the cruise flight state criterion is not satisfied, maintain the first Three-stage control mode until the drone body meets the cruise flight state criteria.

In some embodiments of the present disclosure, the cruise flight state criteria include: the flight airspeed of the drone body is greater than the stall speed; the pitch angle of the drone body is within ±3°; the pitch angle rate of the drone body is within the range of ±3°. between ±10°/s.

In some embodiments of the present disclosure, the ball-borne solar-powered UAV further includes: an optical fiber inertial navigation system, which is connected to the control module in the UAV body, and is used to give a control start time when the cutter is working. There is no electrical connection between the human-machine body and the high-altitude balloon and the delivery system, and the start-up and control time cannot be obtained from the cutting command of the cutter. Therefore, the control and start-up time of the ball-mounted solar drone is given by the fiber optic inertial navigation, that is, the cutter is working at the moment, no one is unmanned. The body of the drone is in a weightless state in an instant. After sensing the weightless state of the drone body, the fiber optic inertial navigation sends a control signal to the control module in the drone body, and starts to execute the ball-mounted solar drone delivery control method provided by the present disclosure. .

Based on the above description, those skilled in the art should have a clear understanding of the method for controlling the launch of a spherical solar drone provided by the embodiments of the present disclosure.

To sum up, the ball-mounted solar drone delivery control method provided by the embodiments of the present disclosure is aimed at the process of the ball-mounted solar drone after the ball-mounted solar drone is put into horizontal flight, the roll channel, the pitch channel and the The control logic of the heading channel and the question of when the three control channels intervene provide a feasible control scheme, so that the launch process of the spherical solar UAV can be carried out smoothly.

It should also be noted that the directional terms mentioned in the embodiments, such as "up", "down", "front", "rear", "left", "right", etc., only refer to the directions of the drawings, not used to limit the scope of protection of the present disclosure. Throughout the drawings, the same elements are denoted by the same or similar reference numbers. Conventional structures or constructions will be omitted when it may lead to obscuring the understanding of the present disclosure.

Moreover, the shapes and sizes of the components in the figures do not reflect the actual size and proportion, but merely illustrate the contents of the embodiments of the present disclosure. Furthermore, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Similarly, it will be appreciated that in the above description of exemplary embodiments of the disclosure, various features of the disclosure are sometimes grouped together into a single embodiment, figure, or its description. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the foregoing claims reflect, disclosed aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of the present disclosure.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present disclosure in detail. It should be understood that the above-mentioned specific embodiments are only specific embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure should be included within the protection scope of the present disclosure.

Claims (5)

1. A ball-borne solar-powered UAV launch control method, wherein attitude control is performed through a pitch channel, a roll channel and a heading channel, and the ball-borne solar-powered UAV comprises: drone body; A high-altitude balloon, connected to the drone body by a tether; and Cutter, used to cut the rope between the high-altitude balloon and the drone body; Starting from the working time of the cutter to the end of the drone body entering cruising flight, the ball-borne solar drone delivery control method includes: Step A: After the cutter works, pull up through the pitch channel, maintain the zero position in the roll channel, and stabilize the heading channel, so that the drone body reaches the first pitch angle; Step B: The UAV body is made to reach the second pitch angle from the first pitch angle by performing zero position control and stabilization of the heading channel through the pitch channel pull-up, the roll angle of the roll channel and the stabilization of the heading channel; Step C: Pull up the pitch channel, perform zero position control on the roll angle of the roll channel, and stabilize the heading channel, so that the drone body can reach the third pitch angle from the second pitch angle; and Step D: After the drone body reaches the third pitch angle, when the drone body meets the cruise flight state criterion, it starts to enter the cruise flight, and the delivery control process ends; the step D includes: Step D1: If the cruise flight state criterion is met, enter the cruise flight; Step D2: if the cruise flight state criterion is not met, maintain the control mode of the third stage until the drone body meets the cruise flight state criterion; Wherein, the first pitch angle, the second pitch angle and the third pitch angle are the angles between the axis of the drone body and the horizontal plane, the first pitch angle, the second pitch angle and the third pitch angle is between -90° to 0° and increases sequentially; Before the working time of the cutter, the pitch channel controls the elevator declination angle of the drone body to maintain a negative value; In the step A and the step B, the pitch channel controls the elevator deflection angle to be the angle maintained before the cutter working time; In the step C, the pitch channel controls the declination angle of the elevator in real time, so that the UAV body is located at the pitch angle position calculated by the optimal track tracking under the premise of minimum acceleration; The working moment of the cutter is the moment when the initial condition of the drone body meets the delivery requirement; Wherein, the delivery requirements include: the three-axis attitude angular rate of the spherical solar UAV is less than ±5°/s, and the wind speed is less than 2m/s. 2. The ball-borne solar-powered drone delivery control method according to claim 1, wherein the first pitch angle is -70°, the second pitch angle is -50°, and the third pitch angle is -20° °. 3. The ball-mounted solar-powered UAV launching control method according to claim 1, the pitch angle of the UAV body at the initial moment of launching is -90°, and the heading of the UAV body in the pulling process The direction of the angle is the direction in which the drone controls the flight. 4. The ball-mounted solar-powered drone delivery control method according to claim 1, wherein the cruise flight state criterion comprises: The flying airspeed of the drone body is greater than the stall speed; The pitch angle of the drone body is within ±3°; The pitch rate of the UAV body is between ±10°/s. 5. The ball-mounted solar-powered UAV delivery control method according to any one of claims 1 to 4, the ball-mounted solar-powered UAV further comprises: optical fiber inertial navigation, and a control module in the UAV body Consecutive, used to give the control start time when the cutter is working.

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