A method and system for remotely controlling the speed of take-off and landing of an unmanned helicopter
Patent Information
- Application Number
- CN202610766294.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-29
- Publication Date
- 2026-10-09
AI Technical Summary
这一现状不仅限制了应急操作的可实施范围，更在关键时刻影响了应急响应的效率，极大降低了复杂故障情况下无人直升机起降的安全性
1）在离地阶段，保留自主起飞快速提总距逻辑，操作人员只需解除快速提总距保险，无人直升机即可自主离地并达到安全天向速度，大幅降低了遥控起飞操作的难度，使非专业人员也能在紧急情况下完成起飞操作。
Smart Images
Figure CN122883670A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of navigation and flight control for unmanned helicopters, and in particular to a remote control speed take-off and landing control method and system for unmanned helicopters. Background Technology
[0002] In the field of modern aviation applications, unmanned helicopters, with their unique vertical takeoff and landing and hovering capabilities, demonstrate unparalleled maneuverability and flexibility. Their long endurance and powerful payload capacity have led to their widespread and in-depth application in numerous fields such as military reconnaissance, civilian surveying, and logistics transportation, making them an indispensable aviation tool for various industries.
[0003] However, during the critical flight phases of fully autonomous takeoff and landing, potential malfunctions remain a significant factor hindering the safe and stable operation of unmanned helicopters. Sensor and navigation system failures are particularly prominent. When the altitude sensor malfunctions, the unmanned helicopter cannot accurately determine the timing of touchdown during descent, potentially resulting in premature or delayed landing. This could not only lead to landing failure but also cause serious damage to the aircraft, causing mission interruption or even rendering the unmanned helicopter unusable. Conversely, if the navigation system malfunctions, the unmanned helicopter will instantly lose accurate positioning information, failing to find the preset landing point and easily entering dangerous areas, leading to unpredictable safety accidents.
[0004] Faced with the aforementioned complex malfunctions, manual remote control becomes a crucial means of ensuring the safety of unmanned helicopters in emergencies. Currently, most manual remote control methods employ a control strategy that directly controls the collective pitch vertically, the attitude longitudinally and laterally, and the directional angular rate. While this inner-loop direct control method enables rapid response, it places extremely high demands on the operator's technical skills and practical experience. Only professionally trained and licensed unmanned helicopter pilots can successfully complete emergency operations. This situation not only limits the scope of feasible emergency operations but also affects the efficiency of emergency response at critical moments, significantly reducing the safety of unmanned helicopter takeoffs and landings under complex malfunction conditions.
[0005] Therefore, there is an urgent need to provide a solution for a remote control speed take-off and landing control method and system for unmanned helicopters. Summary of the Invention
[0006] To address the above problems, the present invention provides a remote control speed take-off and landing control method and system for unmanned helicopters. When an unmanned helicopter encounters extreme and complex conditions such as altitude sensor failure or navigation system failure, it can complete emergency take-off and landing procedures by relying on pure inertial speed and according to the designed remote control speed take-off and landing control strategy.
[0007] According to a first aspect of the present invention, a remote-controlled speed take-off and landing control method for an unmanned helicopter is provided, including a remote-controlled speed take-off control process and a remote-controlled speed landing control process; The remote-controlled speed takeoff control process includes: Upon receiving the takeoff command, and after determining that the unmanned helicopter meets the takeoff conditions, it enters the takeoff preparation phase. During the takeoff preparation phase, the vertical control mode is set to direct collective control, and after determining that the upward speed command transmitted by the remote controller is greater than 0, the collective pitch is increased autonomously at a fixed rate to control the unmanned helicopter to take off. When the vertical speed of the unmanned helicopter exceeds the ground-to-sky speed threshold, the vertical control mode is switched to vertical speed control, and the joystick of the remote controller is mapped to speed commands, so that the external control personnel can control the unmanned helicopter to fly by manipulating the joystick. Upon receiving the command to switch to autonomous hovering, control the unmanned helicopter to disengage from remote control speed takeoff and switch to autonomous hovering; The remote-controlled speed descent control process includes the following steps: Upon receiving the landing command, and after determining that the unmanned helicopter meets the landing conditions, it enters the landing preparation phase. During the landing preparation phase, the vertical control mode is set to skyward speed control, and the joystick input of the remote controller is mapped to speed commands, allowing the external control personnel to operate the joystick to control the descent of the unmanned helicopter. Once the unmanned helicopter descends to the grounding threshold altitude, it responds to the request to rapidly reduce collective pitch, switches the vertical control mode to direct collective pitch control, and rapidly reduces collective pitch at a fixed rate. When the total distance is less than the grounding threshold total distance, the total distance is set to 0, and the unmanned helicopter is made to land smoothly.
[0008] In the above scheme, during the takeoff preparation phase, the longitudinal control mode is set to pitch angle control, the lateral control mode is set to roll angle control, and the heading control mode is set to heading angular rate control; wherein, the pitch angle is given as trim pitch angle, the roll angle is given as trim roll angle, and the heading angular rate is given as 0.
[0009] In the above scheme, when the unmanned helicopter enters the azimuth speed control mode, the longitudinal control mode switches to forward speed control, the lateral control mode switches to lateral speed control, and the heading control mode maintains heading angular rate control.
[0010] In the above scheme, the mapping of the joystick of the remote controller to the speed command includes: the azimuth speed command comes from the up and down channel of the first joystick, the forward speed command comes from the up and down channel of the second joystick, the lateral speed command comes from the left and right channel of the second joystick, and the yaw rate command comes from the left and right channel of the first joystick.
[0011] In the above scheme, the total distance is increased autonomously at a fixed rate, specifically including: when the total distance is less than a first threshold, the total distance is increased at a first rate; when the total distance is between the first threshold and the second threshold, the total distance is increased at a second rate; when the total distance is greater than the second threshold, the total distance is increased at a third rate; wherein, the first rate > the second rate > the third rate.
[0012] In the above scheme, ensuring a smooth landing for the unmanned helicopter specifically includes: switching the longitudinal control mode to pitch angle control, switching the lateral control mode to roll angle control, and maintaining the heading angular rate control; wherein, the pitch angle is given as the trim pitch angle, the roll angle is given as the trim roll angle, and the heading angular rate is given as 0.
[0013] In the above scheme, the process of switching to autonomous hovering includes: the flight control system controls the unmanned helicopter to decelerate, and when the speed drops to the hovering speed threshold, the unmanned helicopter is controlled to hover at a fixed point with the current position, altitude and heading as the target.
[0014] In the above scheme, the takeoff conditions that the unmanned helicopter must meet include: the unmanned helicopter is on the ground, the engine is in cruise mode, the remote controller is working properly, and the current flight mode is remote control speed mode.
[0015] In the above scheme, the landing conditions that the unmanned helicopter must meet include: the unmanned helicopter is in the air, the remote controller is working properly, and the current flight mode is remote control speed mode.
[0016] According to a second aspect of the present invention, a remote-controlled speed take-off and landing control system for an unmanned helicopter is provided for implementing the method described in any one of the above solutions, the system comprising: The remote-controlled speed takeoff control module is configured as follows: The first receiving unit receives the takeoff command, and the first judging unit enters the takeoff preparation stage after judging that the unmanned helicopter meets the takeoff conditions. During the takeoff preparation phase, the vertical control mode is set to direct collective control, and after determining that the upward speed command transmitted by the remote controller is greater than 0, the collective pitch is increased autonomously at a fixed rate to control the unmanned helicopter to take off. When the vertical speed of the unmanned helicopter exceeds the ground-to-sky speed threshold, the vertical control mode is switched to vertical speed control, and the joystick of the remote controller is mapped to speed commands, so that the external control personnel can control the unmanned helicopter to fly by manipulating the joystick. Upon receiving the command to switch to autonomous hovering, control the unmanned helicopter to disengage from remote control speed takeoff and switch to autonomous hovering; The remote-controlled speed descent control module is configured as follows: The second receiving unit receives the landing command, and the second judging unit enters the landing preparation stage after judging that the unmanned helicopter meets the landing conditions. During the landing preparation phase, the vertical control mode is set to skyward speed control, and the joystick input of the remote controller is mapped to speed commands, allowing the external control personnel to operate the joystick to control the descent of the unmanned helicopter. Once the unmanned helicopter descends to the grounding threshold altitude, it responds to the request to rapidly reduce collective pitch, switches the vertical control mode to direct collective pitch control, and rapidly reduces collective pitch at a fixed rate. When the total distance is less than the grounding threshold total distance, the total distance is set to 0, and the unmanned helicopter is made to land smoothly.
[0017] The beneficial effects of this invention are: 1) During the takeoff phase, the autonomous takeoff rapid collective pitch increase logic is retained. The operator only needs to release the rapid collective pitch increase safety, and the unmanned helicopter can take off autonomously and reach a safe azimuth speed, which greatly reduces the difficulty of remote control takeoff operation and enables non-professionals to complete the takeoff operation in emergency situations.
[0018] 2) During the grounding phase, the autonomous landing rapid collective pitch reduction logic is retained. After the external control personnel visually observe that the unmanned helicopter has reached a safe altitude from the ground, the rapid collective pitch reduction safety is released, and the vertical control mode switches from speed control to direct collective pitch control. The collective pitch is rapidly reduced at a fixed rate, ultimately achieving a smooth grounding of the UAV, which greatly reduces the complexity and risk of remote landing operations. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the remote-controlled speed takeoff process of the present invention.
[0021] Figure 2 This is a flowchart of the remote control speed takeoff control strategy of the present invention.
[0022] Figure 3 This is a schematic diagram of the remote control required for this invention.
[0023] Figure 4 This is a schematic diagram of the remote-controlled descent process of the present invention.
[0024] Figure 5 This is a flowchart of the remote control speed descent control strategy of the present invention.
[0025] Figure 6 It is a curve showing the change of total distance from takeoff to remote control speed over time.
[0026] Figure 7 It is a curve showing the change of remote control speed, takeoff speed, and azimuth speed over time.
[0027] Figure 8 It is a curve showing the change of remote-controlled speed, takeoff pitch angle, and time.
[0028] Figure 9 It is a curve showing the change of remote control speed, takeoff roll angle, and time.
[0029] Figure 10 It is a curve showing the change of total distance of descent from remote control speed over time.
[0030] Figure 11 It is a curve showing the change of remote-controlled descent speed and celestial velocity over time.
[0031] Figure 12 It is a curve showing the change of remote-controlled descent pitch angle over time.
[0032] Figure 13 It is a curve showing the change of remote-controlled speed, descent roll angle, and time.
[0033] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0034] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.
[0035] The terms "first," "second," etc., used in this disclosure are for distinguishing similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented, for example, in orders other than those illustrated or described herein.
[0036] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.
[0037] Multiple, including two or more.
[0038] And / or, it should be understood that, for the purposes of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.
[0039] One embodiment of the technical solution of the present invention provides a remote speed take-off and landing control method for an unmanned helicopter, including a remote speed take-off control process and a remote speed landing control process.
[0040] like Figures 1-3 As shown, the remote-controlled speed takeoff control process includes four stages: takeoff preparation, rapid collective pitch increase, remote-controlled speed climb, and autonomous hovering, as detailed below: Takeoff preparation: After receiving the "remote speed takeoff" command, the flight control system enters the takeoff preparation phase after determining that the unmanned helicopter meets the takeoff conditions; During this phase, the unmanned helicopter remains on the ground. The internal control personnel start the unmanned helicopter engine, warm it up, and then cruise. After cruising, the external control personnel send a "self-pilot speed control command" via the remote controller to switch the unmanned helicopter's flight mode to remote control speed flight. The unmanned helicopter is judged to meet all the conditions for remote control speed takeoff: (1) it is on the ground; (2) the remote controller is working properly; (3) the engine is in cruise mode; and (4) the flight mode is remote control speed flight. This process continues until the internal control personnel send a "remote control speed takeoff command" via the ground station.
[0041] The criteria for determining if the remote control is working properly are: if no data is received for 0.3 seconds, the remote control is considered to be malfunctioning; otherwise, the remote control is considered to be working properly.
[0042] The flight modes include two types: autonomous mode and remote control speed mode. You can switch between autonomous mode and remote control speed mode through ground station software or remote control joystick.
[0043] Traditional manual remote-controlled takeoff requires the operator to control collective pitch and attitude throughout the entire process, with takeoff conditions entirely dependent on human judgment. This invention, for the first time, incorporates safety check logic for autonomous takeoff, such as engine cruise status and remote controller communication health, into the remote control speed mode, forming a dual confirmation mechanism. Only after both the system and the operator jointly confirm safety is the takeoff process allowed, significantly reducing the risk of takeoff accidents caused by misoperation or equipment malfunction. Furthermore, the clear distinction between remote control speed mode and autonomous mode lays the foundation for seamless switching between subsequent modes.
[0044] Rapidly increase collective pitch: After entering the takeoff preparation phase, record the takeoff point position, altitude, and heading, and set the vertical control mode to direct collective pitch control with an initial collective pitch of 0; the longitudinal control mode is pitch angle control, and the pitch angle is set to the trim pitch angle. The lateral control mode is roll angle control, and the roll angle setpoint is the trim roll angle. The heading control mode is heading angular rate control, with the heading angular rate set to 0. After determining that the heading speed command transmitted from the remote controller is greater than 0, it autonomously increases collective pitch at a fixed rate to control the unmanned helicopter to take off. Among them, the origin landing is achieved by recording the takeoff point position, altitude, and heading; Direct collective pitch control is a manual or open-loop control mode. In this mode, the flight control system does not calculate the collective pitch in a closed loop based on the current vertical speed. Instead, it directly follows the instructions of the external controller (such as toggling a switch) or changes the collective pitch value at a preset fixed rate. It simply adjusts the collective pitch to X degrees or increases / decreases the collective pitch at a rate of Y degrees / second, regardless of the resulting climb or descent speed of the helicopter. This is typically used in critical moments before takeoff or landing.
[0045] Autonomous collective pitch increase is a specific action performed in direct collective pitch control mode. It refers to the flight control system automatically increasing the collective pitch at a fixed rate, without requiring manual input from the remote controller's collective pitch lever. During takeoff, once a greater-than-zero upward speed command is detected from the remote controller (i.e., the operator indicates an intention to take off), the flight control system autonomously and smoothly increases the collective pitch, allowing the unmanned helicopter to take off stably, thus avoiding loss of control due to excessive manual intervention.
[0046] The aforementioned "vertical control modes" mainly include direct collective pitch control mode, azimuth speed control mode, and altitude control mode. Direct collective pitch control mode is a completely open-loop control, issuing commands directly to the collective pitch according to specific rules. In azimuth speed control mode, the azimuth speed command and current azimuth speed are first acquired, and then the command from the azimuth speed to the collective pitch is calculated through control, thus controlling the azimuth speed of the unmanned helicopter. In altitude control mode, the system first calculates the azimuth speed command based on the given altitude command and the current actual altitude, and then invokes azimuth speed control to achieve precise altitude control of the unmanned helicopter.
[0047] The aforementioned "longitudinal control mode" mainly includes pitch angle control mode, forward speed control mode, and forward distance control mode. In pitch angle control mode, the system first acquires the pitch angle command and the current pitch angle, then calculates the pitch angle to cyclic pitch command, thereby controlling the pitch angle of the unmanned helicopter. In forward speed control mode, the system first calculates the pitch angle command based on the given forward speed command and the current forward speed, then calls pitch angle control to control the forward speed of the unmanned helicopter. In forward distance control mode, the system calculates the forward speed command based on the forward distance, then sequentially calls forward speed control and pitch angle control to precisely control the forward position of the unmanned helicopter.
[0048] The aforementioned "lateral control mode" mainly includes roll angle control mode, lateral speed control mode, and lateral distance control mode. In roll angle control mode, the roll angle command and the current roll angle are first acquired, and then the roll angle is calculated to obtain the lateral periodic pitch command, thereby controlling the unmanned helicopter's roll angle. In lateral speed control mode, the system first calculates the roll angle command based on the given lateral speed command and the current lateral speed, and then calls the roll angle control to control the unmanned helicopter's lateral speed. In lateral distance control mode, the system calculates the lateral speed command based on the lateral distance, and then sequentially calls the lateral speed control and roll angle control to achieve precise control of the unmanned helicopter's lateral position.
[0049] The aforementioned "heading control mode" mainly includes a heading angular rate control mode and a heading angle control mode. In the heading angular rate control mode, the heading angular rate command and the current heading angular rate are first acquired, and then the command from the heading angular rate to the tail rotor pitch is obtained through control calculation, thereby controlling the heading angular rate of the unmanned helicopter. In the heading angle control mode, the system first calculates the heading angular rate command based on the given heading angle command and the current actual heading angle, and then invokes the heading angular rate control to achieve precise control of the unmanned helicopter's heading angle.
[0050] This invention considers the pitch and roll angles of an unmanned helicopter in a state of force and torque balance when hovering in windless conditions; therefore, it is necessary to balance the pitch angle. Matching roll angle .
[0051] The aforementioned "autonomous collective pitch increase at a fixed rate" includes three stages: high speed, medium speed, and low speed. In the high-speed stage, when the collective pitch is less than A1, the unmanned helicopter increases the collective pitch at a rate of B1; in the medium-speed stage, when the collective pitch is between A1 and A2, the unmanned helicopter increases the collective pitch at a rate of B2; and in the low-speed stage, when the collective pitch is greater than A2, the unmanned helicopter increases the collective pitch at a rate of B3. Where A1... <A2<A3,B1> B2>B3. For example... Figure 6 The figure shows the collective pitch variation curve over time when a certain type of unmanned helicopter is controlled by the remote speed takeoff control strategy described in the invention. When the collective pitch of this type of unmanned helicopter is less than 3°, the collective pitch is increased by 0.65° / s; when the collective pitch is 3°~5°, the collective pitch is increased by 0.6° / s; and when the collective pitch is greater than 5°, the collective pitch is increased by 0.5° / s.
[0052] In traditional manual remote takeoff, operators must precisely control the collective pitch increase via the throttle lever, especially at the critical takeoff point. This can easily lead to drastic attitude changes due to excessively rapid collective pitch increases or takeoff failure due to excessively slow increases. This invention integrates autonomous, rapid collective pitch increase logic into the remote control speed mode. The operator only needs to provide a directional speed command greater than 0, and the system automatically increases the collective pitch at three stages. The three-stage rate design conforms to the aerodynamic characteristics of a helicopter takeoff: the initial stage has a strong ground effect, allowing for high-speed collective pitch increases; the middle stage is a transition; and the later stage slows down as the predetermined climb rate approaches, ensuring a smooth and rapid takeoff. This design allows even unlicensed personnel to safely complete takeoff, significantly lowering the operational threshold for emergency takeoffs.
[0053] Remote-controlled speed climb: When the unmanned helicopter's vertical speed exceeds the ground-based vertical speed threshold, the system automatically switches from vertical control mode to vertical speed control and maps the remote controller's joystick inputs to speed commands. The operator then controls the helicopter's flight by manipulating the joystick, including forward, backward, left, right, left yaw, right yaw, climb, and descent. This phase continues until the operator visually observes the helicopter reaching the desired altitude and sends the "Speed remote control to autopilot" command. Figure 7 The figure shows the curve of the sky speed as a function of time when a certain type of unmanned helicopter takes off using the remote control speed takeoff control strategy described in the invention. The sky speed threshold for this type of unmanned helicopter is 0.5 m / s, and the corresponding time is 1416.6 s, at which point the unmanned helicopter enters the remote control speed climb phase.
[0054] The schematic diagram of the remote control involved in the invention is as follows: Figure 3 As shown. The minimum unit required for the remote controller consists of two joysticks that can move up, down, left, and right, and two three-position levers. Joystick 1 (up / down) is the yaw rate command channel, and joystick 1 (left / right) is the yaw angle rate command channel. Joystick 2 (up / down) is the forward speed command channel, and joystick 2 (left / right) is the lateral speed command channel. Lever 1 is the flight mode switching channel, and lever 2 is the rapid collective pitch reduction request channel. When the rapid collective pitch reduction request channel is in the low position and the yaw rate command channel is pulled to its lowest position, it is considered that rapid collective pitch reduction is required. The flight control system will exit the yaw rate control mode and switch to the direct control collective pitch mode, reducing collective pitch at a fixed rate.
[0055] The "takeoff altitude threshold" is selected from the altitudes that corresponded to the takeoff altitude thresholds when the autonomous takeoff altitude was previously reached.
[0056] The aforementioned "vertical speed control" uses vertical speed commands derived from the up / down movement of the joystick 1 on the remote control. After joystick mapping, the vertical speed command range is -1.5m / s to 1.5m / s, and the vertical speed command is set at 0.3m / s. Softening, dead zone 0.15m / s.
[0057] The forward speed command for the aforementioned "forward speed control" originates from the up / down channel of the joystick 2 on the remote control. After the joystick is mapped, the range of the forward speed command is -2m / s to 2m / s, and the forward speed command is set at 1m / s. Softening, dead zone 0.2m / s.
[0058] The aforementioned "lateral speed control" uses forward speed commands derived from the left and right channels of the remote control joystick 2. After joystick mapping, the forward speed command range is -2m / s to 2m / s, and the lateral speed command is based on 1m / s. Softening, dead zone 0.2m / s.
[0059] The heading angular rate command for "heading control" originates from the left and right channel lever values of the remote control joystick 1. After lever mapping, the heading angular rate command range is -5° / s to 5° / s, and the heading angular rate command is set at 20° / s. Softening, dead zone 0.5° / s.
[0060] like Figure 8 The figure shows the pitch angle versus time curve during takeoff of a certain type of unmanned helicopter controlled by the remote speed takeoff control strategy described in this invention. The trim pitch angle of this type of unmanned helicopter is -3 degrees. After 1416.6 seconds, the remote speed climb phase is reached, and the pitch angle command is calculated from the forward speed control. Figure 9 The figure shows the roll angle versus time curve during takeoff of a certain type of unmanned helicopter controlled by the remote speed takeoff control strategy described in the invention. The trim roll angle of this type of unmanned helicopter is 3 degrees. After 1416.6s, the remote speed climb phase is reached, and the roll angle command is calculated from the lateral speed control.
[0061] The selection of the switching threshold in this step is based on the altitude corresponding to the airspeed during autonomous takeoff, ensuring a seamless transition from rapid collective pitch increase to speed control and avoiding speed jumps during mode switching. The attitude control inner loop in traditional remote control is upgraded to a speed control outer loop. Operators no longer need to understand the complex relationship between attitude and force; they only need to push the stick in the desired direction, which is intuitive and greatly reduces the difficulty of operation. The softened speed command and deadzone design filter out minor hand tremors, making flight more stable.
[0062] Autonomous hovering: After the operator controls the unmanned helicopter to climb to the desired altitude, they toggle the flight mode switch lever 1 on the remote controller. After receiving the command to switch to autonomous hovering, the flight control system controls the unmanned helicopter to disengage from remote control and take off at the designated speed, switching to autonomous hovering.
[0063] The "switching to autonomous hovering" refers to the flight control system controlling the unmanned helicopter to decelerate, maintain altitude, and keep its heading after an external or internal control personnel send a command, until the speed reaches the hovering speed threshold, at which point the unmanned helicopter hovers at its current position.
[0064] This invention enables a one-button switch between remote-controlled speed mode and fully autonomous hovering, eliminating the need for manual trimming or fine-tuning by the operator. Compared to traditional methods that require gradually reducing speed and switching between multiple modes, this invention allows for mode switching with a single joystick, and automatically remembers the current flight state, preventing hovering position drift. This design makes mission transitions after emergency takeoff safer and more efficient.
[0065] like Figure 4 and Figure 5 As shown, the remote-controlled speed descent control process includes four stages: descent preparation, remote-controlled speed descent, rapid collective pitch reduction, and smooth landing.
[0066] Landing preparation: After receiving the landing command and determining that the unmanned helicopter meets the landing conditions, the landing preparation phase begins. Specifically, during the landing preparation phase, the unmanned helicopter is hovering. The internal control personnel send a remote speed landing command through the ground station. After receiving the command, the flight control system determines that the following remote speed landing conditions are met: (1) in the air; (2) the remote controller is working properly; (3) the flight mode is remote speed flight, and then the process ends.
[0067] The terms "remote controller is working normally" and "flight mode" are consistent with the remote control speed takeoff control strategy.
[0068] Similar to takeoff, this phase involves a system self-check and mode confirmation before landing to ensure landing is performed in remote control speed mode and avoid mode conflicts. Especially in emergency scenarios, the system will forcibly confirm that the remote control link is normal to prevent loss of control during landing.
[0069] Remote control speed reduction: After the landing preparation phase, set the vertical control mode to yaw speed control, the longitudinal control mode to forward speed control, the lateral control mode to side speed control, and the heading control mode to heading angular rate control. Control commands are mapped from the joystick input on the remote controller to speed. The operator controls the joystick to achieve forward, backward, left, right, left yaw, right yaw, climb, and descent maneuvers for the unmanned helicopter.
[0070] The "vertical control mode", "longitudinal control mode", "lateral control mode" and "heading control mode" mentioned therein are consistent with those described in the remote control speed takeoff control strategy.
[0071] This step employs closed-loop speed control throughout, eliminating the need for operators to worry about attitude limits or stall issues; they only need to control the descent rate and translation speed. Compared to traditional manual remote-controlled landings, which require simultaneous coordination of collective pitch, cyclic pitch, and tail rotor, this invention delegates the complex inner-loop control to the flight control system, significantly reducing the difficulty of emergency landings.
[0072] Rapid collective pitch reduction: After the operator controls the unmanned helicopter to descend to the grounding threshold height, they toggle the rapid collective pitch reduction lever on the remote control and pull the sky speed command to the lowest level. This controls the unmanned helicopter to exit sky speed control vertically and switch to direct collective pitch control, rapidly reducing the collective pitch at a fixed rate.
[0073] The aforementioned "rapid reduction of total distance at a fixed rate" refers to reducing the total distance from the current total distance at a fixed rate C° / s. For example... Figure 10 The figure shows the collective pitch versus time curve during the landing of a certain type of unmanned helicopter controlled by the remote-controlled speed landing control strategy described in the invention. This type of unmanned helicopter rapidly descends with a collective pitch of 1.3° / s. At 2336.3s, it reaches the stable touchdown phase, and both pitch and roll commands are switched to trim values.
[0074] During the rapid collective pitch descent phase, the flight control system controls the unmanned helicopter's vertical walkway to rapidly descent the collective pitch at a fixed rate, enabling the unmanned helicopter to touch down at a relatively fast speed. This phase ends when the collective pitch is less than the touchdown collective pitch threshold.
[0075] like Figure 11 The figure shows the curve of the azimuth velocity over time when controlling the landing of a certain type of unmanned helicopter using the remote control speed landing control strategy described in the invention. When the unmanned helicopter is touched down by an external operator, the azimuth velocity is near 0.
[0076] This step employs a trigger mechanism with the joystick at its lowest position and the stick at its lowest setting to prevent false triggering, providing high safety redundancy. The rapid collective pitch reduction simulates the action of a professional pilot rapidly reducing collective pitch at touchdown, but is executed automatically by the flight controller at a fixed rate, avoiding hard landings or drifts caused by excessively fast or slow human intervention. Upon approaching the ground, the external controller switches to open-loop collective pitch control, preventing malfunctions that might occur in the closed-loop speed control system due to altitude sensor failure or air pressure disturbances (such as premature or late touchdown).
[0077] Smooth grounding: After the flight control system determines that the collective pitch is less than the grounding threshold, it sets the collective pitch to 0, switches to pitch control in the longitudinal direction, switches to roll control in the lateral direction, and maintains yaw rate control. The pitch angle setpoint is the trim pitch angle. The roll angle is given as the trim roll angle. With the heading angular rate set to 0, a smooth landing for the unmanned helicopter is achieved. Figure 12The figure shows the pitch angle variation over time when controlling the landing of a certain type of unmanned helicopter using the remote-controlled speed landing control strategy described in the invention. Before 2336.3s, the pitch angle command is calculated from the forward speed control; after 2336.3s, the pitch angle command is the trim value -3°. Figure 13 The figure shows the roll angle versus time curve when controlling the landing of a certain type of unmanned helicopter using the remote control speed landing control strategy described in the invention. Before 2336.3s, the roll angle command is calculated by lateral speed control; after 2336.3s, the roll angle command is the trim value of 3°.
[0078] Among them, the "pitch angle trimming" "Balancing roll angle" "Consistent with the remote speed takeoff control strategy described."
[0079] During the stable grounding phase, the pitch angle of the longitudinal channel remains at the trim pitch angle, the roll angle of the lateral channel remains at the trim roll angle, the angular rate of the heading channel remains at 0, and the collective pitch remains at 0, so that the unmanned helicopter can land smoothly.
[0080] This step immediately switches to attitude hold after grounding to prevent the helicopter from tipping over due to ground effect or external forces. The trim attitude is selected based on a windless hovering equilibrium state to ensure uniform stress on the main rotor and fuselage structure upon touchdown. Compared to the traditional method where the operator manually returns the centering stick and corrects the attitude, this invention achieves automatic attitude stabilization after touchdown. Even if the operator releases the stick at this time, the helicopter will not tip over, greatly improving landing safety.
[0081] According to a second aspect of the present invention, a remote-controlled speed take-off and landing control system for an unmanned helicopter is provided for implementing the method described in any one of the above solutions, the system comprising: The remote-controlled speed takeoff control module is configured as follows: The first receiving unit receives the takeoff command, and the first judging unit enters the takeoff preparation stage after judging that the unmanned helicopter meets the takeoff conditions. During the takeoff preparation phase, the vertical control mode is set to direct collective control, and after determining that the upward speed command transmitted by the remote controller is greater than 0, the collective pitch is increased autonomously at a fixed rate to control the unmanned helicopter to take off. When the vertical speed of the unmanned helicopter exceeds the ground-to-sky speed threshold, the vertical control mode is switched to vertical speed control, and the joystick of the remote controller is mapped to speed commands, so that the external control personnel can control the unmanned helicopter to fly by manipulating the joystick. Upon receiving the command to switch to autonomous hovering, control the unmanned helicopter to disengage from remote control speed takeoff and switch to autonomous hovering; The remote-controlled speed descent control module is configured as follows: The second receiving unit receives the landing command, and the second judging unit enters the landing preparation stage after judging that the unmanned helicopter meets the landing conditions. During the landing preparation phase, the vertical control mode is set to skyward speed control, and the joystick input of the remote controller is mapped to speed commands, allowing the external control personnel to operate the joystick to control the descent of the unmanned helicopter. Once the unmanned helicopter descends to the grounding threshold altitude, it responds to the request to rapidly reduce collective pitch, switches the vertical control mode to direct collective pitch control, and rapidly reduces collective pitch at a fixed rate. When the total distance is less than the grounding threshold total distance, the total distance is set to 0, and the unmanned helicopter is made to land smoothly.
[0082] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.
[0083] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.
[0084] Through the above description of the embodiments, those skilled in the art can clearly understand that the above implementation methods can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of the present invention.
[0085] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.
Claims
1. A remote-controlled speed takeoff and landing control method for an unmanned helicopter, characterized in that, This includes the remote-controlled speed takeoff control process and the remote-controlled speed landing control process; The remote-controlled speed takeoff control process includes: Upon receiving the takeoff command, and after determining that the unmanned helicopter meets the takeoff conditions, it enters the takeoff preparation phase. During the takeoff preparation phase, the vertical control mode is set to direct collective control, and after determining that the upward speed command transmitted by the remote controller is greater than 0, the collective pitch is increased autonomously at a fixed rate to control the unmanned helicopter to take off. When the vertical speed of the unmanned helicopter exceeds the ground-to-sky speed threshold, the vertical control mode is switched to vertical speed control, and the joystick of the remote controller is mapped to speed commands, so that the external control personnel can control the unmanned helicopter to fly by manipulating the joystick. Upon receiving the command to switch to autonomous hovering, control the unmanned helicopter to disengage from remote control speed takeoff and switch to autonomous hovering; The remote-controlled speed descent control process includes the following steps: Upon receiving the landing command, and after determining that the unmanned helicopter meets the landing conditions, it enters the landing preparation phase. During the landing preparation phase, the vertical control mode is set to skyward speed control, and the joystick input of the remote controller is mapped to speed commands, allowing the external control personnel to operate the joystick to control the descent of the unmanned helicopter. Once the unmanned helicopter descends to the grounding threshold altitude, it responds to the request to rapidly reduce collective pitch, switches the vertical control mode to direct collective pitch control, and rapidly reduces collective pitch at a fixed rate. When the total distance is less than the grounding threshold total distance, the total distance is set to 0, and the unmanned helicopter is made to land smoothly.
2. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, During the takeoff preparation phase, the longitudinal control mode is set to pitch angle control, the lateral control mode to roll angle control, and the heading control mode to heading angular rate control; wherein, the pitch angle is given as the trim pitch angle, the roll angle is given as the trim roll angle, and the heading angular rate is given as 0.
3. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 2, characterized in that, Once the unmanned helicopter enters the azimuth speed control mode, the longitudinal control mode switches to forward speed control, the lateral control mode switches to lateral speed control, and the heading control mode maintains heading angular rate control.
4. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, The mapping of the joysticks in the remote control to speed commands includes: the azimuth speed command comes from the up-down channel of the first joystick, the forward speed command comes from the up-down channel of the second joystick, the lateral speed command comes from the left-right channel of the second joystick, and the yaw rate command comes from the left-right channel of the first joystick.
5. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, The total distance is increased autonomously at a fixed rate, specifically including: when the total distance is less than a first threshold, the total distance is increased at a first rate; when the total distance is between the first threshold and the second threshold, the total distance is increased at a second rate; when the total distance is greater than the second threshold, the total distance is increased at a third rate; wherein, the first rate > the second rate > the third rate.
6. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, Enabling the unmanned helicopter to land smoothly includes: switching the longitudinal control mode to pitch angle control, switching the lateral control mode to roll angle control, and maintaining the heading angular rate control; wherein, the pitch angle is given as the trim pitch angle, the roll angle is given as the trim roll angle, and the heading angular rate is given as 0.
7. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, The process of switching to autonomous hovering includes: the flight control system controls the unmanned helicopter to decelerate, and when the speed drops to the hovering speed threshold, the unmanned helicopter is controlled to hover at a fixed point with the current position, altitude and heading as the target.
8. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, The takeoff conditions that an unmanned helicopter must meet include: the unmanned helicopter is on the ground, the engine is in cruise mode, the remote controller is working properly, and the current flight mode is remote control speed mode.
9. The remote control speed takeoff and landing control method for unmanned helicopters according to claim 1, characterized in that, The landing conditions that an unmanned helicopter must meet include: the unmanned helicopter is in the air, the remote controller is working properly, and the current flight mode is remote control speed mode.
10. A remote-controlled speed take-off and landing control system for an unmanned helicopter, characterized in that, The system for implementing the method as described in any one of claims 1-9 includes: The remote-controlled speed takeoff control module is configured as follows: The first receiving unit receives the takeoff command, and the first judging unit enters the takeoff preparation stage after judging that the unmanned helicopter meets the takeoff conditions. During the takeoff preparation phase, the vertical control mode is set to direct collective control, and after determining that the upward speed command transmitted by the remote controller is greater than 0, the collective pitch is increased autonomously at a fixed rate to control the unmanned helicopter to take off. When the vertical speed of the unmanned helicopter exceeds the ground-to-sky speed threshold, the vertical control mode is switched to vertical speed control, and the joystick of the remote controller is mapped to speed commands, so that the external control personnel can control the unmanned helicopter to fly by manipulating the joystick. Upon receiving the command to switch to autonomous hovering, control the unmanned helicopter to disengage from remote control speed takeoff and switch to autonomous hovering; The remote-controlled speed descent control module is configured as follows: The second receiving unit receives the landing command, and the second judging unit enters the landing preparation stage after judging that the unmanned helicopter meets the landing conditions. During the landing preparation phase, the vertical control mode is set to skyward speed control, and the joystick input of the remote controller is mapped to speed commands, allowing the external control personnel to operate the joystick to control the descent of the unmanned helicopter. Once the unmanned helicopter descends to the grounding threshold altitude, it responds to the request to rapidly reduce collective pitch, switches the vertical control mode to direct collective pitch control, and rapidly reduces collective pitch at a fixed rate. When the total distance is less than the grounding threshold total distance, the total distance is set to 0, and the unmanned helicopter is made to land smoothly.