148 results about "Quad rotor" patented technology

The invention relates to a device and method for composition based on a small quad-rotor unmanned aerial vehicle and belongs to the technical field of mobile robot positioning and navigation. The small quad-rotor unmanned aerial vehicle can rapidly enter a complex environment which a mobile robot cannot enter, carried laser radar is utilized to construct a two-dimensional map in real time according to an SLAM method, self localization and navigation of the unmanned aerial vehicle can be achieved by combining an IMU device and the like, and efficient exploration of a true complex area is achieved; the height of the small quad-rotor unmanned aerial vehicle can be conveniently adjusted to obtain two-dimensional maps on horizontal planes of different heights; the small quad-rotor unmanned aerial vehicle is rapid in movement speed and more flexible, movement and mapping of the small quad-rotor unmanned aerial vehicle are not subject to disturbance of obstacles on the ground, the range limitation of a detecting robot is broken through, the small quad-rotor unmanned aerial vehicle is extremely high in practical value, and accurate and rapid map construction can be achieved; compared with robot environment composition, the rotor wing robot can perform environment scouting more rapidly and more flexibly, and three-dimensional spatial images can be obtained.

The invention discloses a nonlinear output feedback flight control method for a quad-rotor unmanned aerial vehicle. The nonlinear output feedback flight control method for the quad-rotor unmanned aerial vehicle comprises the following steps of: (1) determining a kinematic model of the quad-rotor unmanned aerial vehicle under an inertial coordinate system and a kinematic model of the quad-rotor unmanned aerial vehicle under a body coordinate system; (2) designing an attitude control system of the quad-rotor unmanned aerial vehicle; defining tracking errors of the attitude angle and the angular speed of the quad-rotor unmanned aerial vehicle; designing a filter to perform online estimation on an angular speed signal and obtain an open loop dynamic equation of the tracking errors; and estimating unknown functions in the open loop dynamic equation by adopting neural network feedforward, and designing attitude system control output of the quad-rotor unmanned aerial vehicle; and (3) designing a height control subsystem of the quad-rotor unmanned aerial vehicle; defining height tracking errors and defining auxiliary filtering tracking errors; and designing a height subsystem controller. According to the nonlinear output feedback flight control method for the quad-rotor unmanned aerial vehicle disclosed by the invention, the polarity problem is effectively avoided, a wide-range stable control effect is achieved, the robust performance of the system is greatly improved, and the dependence of a flight controller on an airborne sensor is greatly reduced.

The bird repellent system is particularly adapted to repel various species of birds on and around airports, but may be readily adapted for use in other environments where birds have become a nuisance or hazard. The system includes both a ground vehicle and an airborne vehicle to optimize the effect against both sitting birds and birds in flight. Both vehicles are unmanned and operate autonomously, or by remote control as drones. The airborne vehicle is preferably a quad rotor craft for very slow and hovering flight. Both vehicles are equipped with GPS guidance and are preprogrammed to travel about a predetermined area or route. The two vehicles communicate with one another for optimum effect. Both vehicles include audio systems to broadcast startling sounds and / or bird distress cries in sound frequencies audible to humans as well as in ultrasonic frequencies known to be audible to various species of birds.

The invention discloses a DSP (Digital Signal Processor)-based quad-rotor unmanned aerial vehicle autonomous hover control system and method. The control system is provided with four screw propellers and control units which are arranged on four airfoils respectively; and each control unit is that a master control unit is connected to a ground computer through a wireless network, and a receiver is connected with a signal conversion module and a manual / automatic switching chip in sequence, transmits a received signal transmitted by a remote controller into the manual / automatic switching chip through the signal conversion module, is also connected with the manual / automatic switching chip through the master control unit and is used for transmitting the received signal to the manual / automatic switching chip through the master control unit for controlling driving units to drive direct current brushless motors on the four screw propellers to work. According to the method, kalman filtering processing is performed on sonar data to obtain accurate height data and driver control. According to the system and the method, the autonomous flight capacity of a micro quad-rotor unmanned aerial vehicle and the adaptability to the environment can be effectively enhanced, and the autonomous flight control under indoor environments and outdoor environments can be finished.

The invention discloses a quad-rotor UAV fault tolerance control method based on an adaptive fault estimation observer, and belongs to the field of aviation aircraft control. The method comprises thata fault model of a quad-rotor attitude system is established according to a dynamic model of a quad-rotor UAV by considering a performer fault of a UAV system; a performer of the UAV includes four rotor motors in practicality, faults correspond to the four rotor motors, the fault model is processed, the faults are divided into two groups decoupled mutually, and a final attitude fault model is obtained; according to the provided fault model, the adaptive fault estimation observer is designed, corresponding adaptive laws are provided, the performance fault is estimated, and an H(infinite) method and an interval matrix method are used on external disturbance and parameter nondeterminacy respectively in the design process; and an attitude system error fault model is obtained on the basis of the fault model, a dynamic output feedback fault tolerance controller is designed on the basis of a fault estimated value, and fault tolerance control of the quad-rotor UAV is realized. Influence of the performer fault on performance of the quad-rotor UAV can overcome, and the safety and reliability of the UAV in the flight process are ensured fully.

The invention discloses a nonlinear robust controller design method based on back-stepping and sliding mode control technologies and aimed at a nonlinear model of a quad-rotor unmanned plane. A sliding mode controller of a speed-constant reaching law is designed to an attitude angle system of the quad-rotor unmanned plane, and rapid tracking for the attitude angle is ensured. To realize track tracking for the spatial position of the quad-rotor unmanned plane, a sliding mode surface and a virtual control quantity are constructed according to a stepping back control idea to realize nonlinear control law design and system stability design from the kernel to the external layer of a system. After an equation of the related virtual control quantity is obtained, an expected track value of the attitude angle is obtained by solving the equation via arithmetic inverse operation, and a design method of the speed-constant reaching law is used to determine a final input control law of the quad-rotor unmanned plane system. According to the method of the invention, the characteristic that sliding mode control is uncertain for the model and insensitive to external interference is utilized, robust trace tracking for the nonlinear quad-rotor unmanned plane can be controlled under interference.

The invention relates to a retractable folding quad rotor which comprises a central supporting mechanism and four sets of propeller mechanisms. The improvement of the retractable folding quad rotor is as follows: the four sets of propeller mechanisms are four sets of retractable propeller mechanisms with identical structures; each set of retractable propeller mechanism comprises a bevel pinion, a telescopic rod, a propeller, a motor and a lifting arm mechanism, and also comprises a large conical gear and a servo motor; the servo motor, the large conical gear and the four bevel pinions form driving mechanisms of telescopic rods of the four sets of propeller mechanisms; and under the drive of the servo motor, the four bevel pinions respectively and simultaneously drive the four telescopic rods to realize outward retraction or inward retraction by virtue of screw drive of the screw rods. According to the improvement, four sets of folding mechanisms are arranged, wherein each set of folding mechanism drives each set of telescopic propeller mechanism to fold or unfold. According to the quad rotor, the telescopic mechanisms and the folding mechanisms are additionally arranged, so that the four-rotor body is greatly retracted; and compared with the conventional product, the retractable folding quad rotor disclosed by the invention has the advantages that the size of the quad rotor is effectively reduced, and the quad rotor is convenient to carry.

The invention provides a hybrid finite time control method for quadrotor accurate trajectory tracking. The method comprises the steps: establishing a kinematic model and a dynamical model of a quad-rotor unmanned aerial vehicle; designing a vertical control law of the vertical motion according to a height tracking error of the quadrotor unmanned aerial vehicle and an adaptive integral sliding surface design; on the basis of a horizontal position tracking error of the quadrotor unmanned aerial vehicle, designing a horizontal control law of the horizontal motion based on a backstepping method; and designing a finite time disturbance observer based on the attitude angle of quadrotor unmanned aerial vehicle and designing a precise attitude stability control law by combining a non-singular terminal sliding-mode control law and the finite time disturbance observer. According to the invention, the quad-rotor is classified into three subsystems of the height, horizontal position and attitude and three kinds of control strategies are designed respectively; and on the basis of the hybrid control scheme, the trajectory tracking error is stabilized rapidly. The accurate trajectory tracking ofthe quadrotor can be realized under the condition that the unknown model parameters and the external disturbance are allowed; and the manipulation is more flexible.

The invention relates to the technical field of unmanned aircraft control, and provides a finite-time track and attitude cooperative control algorithm based on multi-variable interference compensation. The defect in the prior art that a traditional quad-rotor unmanned helicopter is poor in control precision, slow in response speed and not ideal in anti-interference effect can be overcome. Meanwhile, the high-precision fast and stable tracking control problem for the track and the posture of the quad-rotor unmanned helicopter under the influence of comprehensive interferences can be solved. Asa result, the safety and the reliability of the system are enhanced. The track and attitude cooperative control method for the quad-rotor unmanned helicopter based on multi-variable interference compensation comprises the following steps of 1, designing a track controller-interference compensator; 2, resolving the attitude; 3, designing an attitude controller-interference compensator. The method is mainly applied to the control occasions of unmanned aircrafts.

The invention discloses an attitude control method and system for a quad-rotor aircraft based on an auto-disturbance rejection control technology, and can effectively improve the robustness of the attitude control of the quad-rotor aircraft. The method comprises the following steps of using auto-disturbance rejection control to implement angular velocity loop control in attitude control; in an auto-disturbance rejection controller, obtaining given angular velocity and angular acceleration after performing smooth noise reduction on a given angular velocity signal by a tracking differentiator; adopting a second-order extended state observer, and performing observation and estimation on the state of each order of the angular velocity control model, internal and external disturbances acting onthe model and the sum of system un-modeled dynamics by using the feedback angular velocity of the controlled object and the control quantity u(t-tau) added to the motor response delay; using the difference between the output quantity of the observer and the given quantity to obtain a preliminary control quantity through the calculation of a nonlinear control rate, using the disturbance estimationquantity obtained by the observer to perform compensation on the basis of the preliminary control quantity, and obtaining the final output control quantity u(t).

The invention discloses a quad-rotor unmanned aerial vehicle visual target tracking method based on a binocular camera. The method comprises the following steps of detecting a tracking target througha target recognition algorithm, finishing the position tracking and scale tracking of the target in pixel significance by using a visual tracking algorithm based on correlation filtering, and judgingwhether a repositioning program needs to be started or a long-term tracker needs to be updated according to a tracking effect; secondly, according to an image area selected by the tracking frame, calculating the relative distance between the quad-rotor unmanned aerial vehicle and the tracking target by using an LK optical flow method, and after coordinate conversion, realizing the global state estimation of the tracking target by using a Kalman filter; and finally, according to the estimated global position and speed state of the target, designing the state quantity of an outer loop control system of the unmanned aerial vehicle to realize the delay-free stable tracking of the tracked target by the unmanned aerial vehicle.

The invention provides an unmanned aerial vehicle patrol and search-and-rescue system based on multi-sensor fusion and a search-and-rescue method. The unmanned aerial vehicle patrol and search-and-rescue system comprises a signal emitter, an unmanned aerial vehicle search-and-rescue system and a ground rescue center, wherein the signal emitter is arranged on a wearable wristband and is used for sending rescue point position information, and the unmanned aerial vehicle search-and-rescue system and the ground rescue center are used for determining personnel positions and personnel information, recording terrain and determining rescue routes. According to the unmanned aerial vehicle patrol and search-and-rescue system based on the multi-sensor fusion and the search-and-rescue method, a flightsub-control system of an unmanned aerial vehicle is composed of a quad-rotor autonomic unmanned aerial vehicle, an image and quantity acquisition and processing module, a signal transmission module and a terrain analysis and route planning module, and can make fast reaction and collect and analyze image information in real time; and image processing is adopted to perform automatic human body recognition, the recognized information is subjected to data matching with a database, whether target personnel are searched or not is determined, and meanwhile, the number of trapped personnel is determined.

An embodiment of the invention discloses an attitude control method and system based on a quad-rotor unmanned helicopter. The method includes the steps: extracting differential signals for controlling reference state input values by a tracking differentiator; acquiring expanded state output quantity under current attitude adjustment based on an expanded state observer; acquiring initial control output quantity of a nonlinear feedback controller based on error design; performing disturbance compensation for the initial control output quantity by unknown disturbance observation values in the expanded state observer to obtain control output values of an inner ring attitude controller. The transient process is arranged, the differential signals of a controlled object are extracted by the tracking differentiator, change of reference input signals is softened by tracking the reference input signals, output overshooting of the system is decreased, and robustness is enhanced.

The invention relates to a flight control method of an unmanned helicopter and provides a posture nonlinear self-adaptive control method of a quad-rotor unmanned helicopter. Progressive tracking control over the flight posture of the helicopter can be effectively achieved under the condition that system parameters like the moment of inertia of the helicopter, the air damping coefficient and mass center offset are unknown. According to the adopted technical scheme, the method comprises the steps that a small quad-rotor unmanned helicopter control design model serves as a controlled object, online estimation is carried out on unknown system parameters through an immersion-invariant set theory, a controller is constructed by utilization of an estimated value, and progressive tracking control over the flight posture of the quad-rotor unmanned helicopter is achieved. The posture nonlinear self-adaptive control method of the quad-rotor unmanned helicopter is mainly applied to flight control of the unmanned helicopter.

The invention discloses a quad-rotor indoor navigation method based on combination of vision and inertia. The method can supply navigation information on the basis of combination of four cameras and an inertial element that are arranged under a motor base of the quad-rotor aircraft if there is no external navigation information indoor. According to the technical scheme, the quad-rotor indoor navigation method based on combination of vision and inertia includes the following steps: 1) extracting and matching characteristic points of images in four directions, which are collected synchronously by the four cameras under the motor base of the quad-rotor aircraft, to obtain a characteristic point matching groups, and pre-integrating the inert information, between adjacent image frames, of the quad-rotor aircraft; 2) tight-coupling the monocular vision in the four directions with the pre-integrated inert information through an optimization method in parallel to obtain four groups of the navigation information of the quad-rotor aircraft; and 3) fusing the four groups of the navigation information to obtain high-precision and high-robust indoor navigation information.

The invention discloses a spherical mechanism for a quad-rotor amphibious robot. The spherical mechanism is composed of a rotor wing mechanism and a spherical shell mechanism, wherein the rotor wing mechanism is composed of a long shaft, a short shaft, a base, four rotor wings and four motors, the spherical shell mechanism is composed of a flexible rod, two fixed bases and a rolling ring, the long shaft is perpendicular to the short shaft, the axis of the long shaft and the axis of the short shaft are located on the same plane, the four rotor wings and the motors are symmetrically installed on the long shaft and the short shaft, and a connecting shaft on the long shaft is connected with the fixed bases of the spherical shell mechanism to enable the rotor wing mechanism to rotate around the long shaft relative to the spherical shell mechanism. The rotor wing mechanism provides power for the robot, and the robot is made to fly in the air or roll on the ground by setting the rotating speed and direction of the four rotor wings. When the robot flies in the air, the spherical shell mechanism serves as a protecting device. When the robot rolls on the ground, the spherical shell mechanism serves as a protecting device and a rolling device. The spherical mechanism has the advantages of being simple in structure, practical, convenient to dismantle, convenient to maintain, low in cost and the like.

The invention discloses a quad-rotor mini-type underwater vehicle. The quad-rotor mini-type underwater vehicle comprises a vehicle body, four both-way propellers and connecting pieces used for installing the both-way propellers. The quad-rotor mini-type underwater vehicle is characterized in that every two of the four both-way propellers are in one group, the two groups of the both-way propellers are symmetrically arranged on the two sides of the vehicle body respectively, propeller rotating shafts of the both-way propellers are obliquely arranged relative to the horizontal plane, and generated propelling force has the component in the heading direction; and the inclination angles of the propeller rotating shafts of the both-way propellers relative to the horizontal plane are equal, the two both-way propellers in each group are distributed in front of and behind the vehicle body, and the propeller rotating shafts of the both-way propellers are opposite in inclination direction. The quad-rotor mini-type underwater vehicle is reasonable in arrangement, the structure is more stable, movement is more flexible, and the vehicle can directly move in the vertical direction, namely, floating or descending. The overall structure is simple, and miniaturization and microminiaturization are facilitated. Conventional products can be adopted in all modules, special requirements are avoided, the independence of the underwater vehicle is guaranteed, and the beneficial effects of low cost, high stability and the like are achieved.

The invention discloses an improved self-disturbance-resistance quad-rotor unmanned aerial vehicle height control method. The method comprises the following steps of step1, based on a mechanism modeling method, establishing a nonlinear dynamic model of a quad-rotor unmanned aerial vehicle height direction; step2, decomposing the nonlinear dynamic model into a linear item and a uncertain item; step3, using a tracking differentiator to obtain a height direction position and a speed expectation value; step4, estimating a disturbance item in a system using a first-order extended state observer; and step5, designing an error feedback control law based on a PD algorithm and feedforward control, and using a disturbance item value estimated by the extended state observer to compensate the uncertain item of the system. An improved tracking differentiator is used to plan a height flight strategy, and an acceleration-uniform speed-deceleration flight mode is constructed so that a quad-rotor unmanned aerial vehicle can rise (or descend) from one height to another height in the shortest time; and a maximum acceleration during flight and a speed of a uniform speed segment can be set autonomously.

The invention relates to the technical field of unmanned aerial vehicle control, and aims to solve a problem of high-precision fast and stable tracking control for a quad-rotor unmanned aerial vehicleunder the influences of a rotor fault and an unknown disturbance boundary so as to achieve the purposes of comprehensively improving the control performance of the quad-rotor unmanned aerial vehicleand enhancing the safety and reliability of the system. The invention relates to an adaptive multi-variable quad-rotor unmanned aerial vehicle finite-time fault-tolerant control method, which comprises the steps of first designing an adaptive finite-time position fault-tolerant controller; second, calculating the attitude, and establishing an analysis relation between a position loop virtual control instruction and an attitude loop reference attitude instruction based on flight characteristics of the quad-rotor unmanned aerial vehicle; and third, designing an adaptive finite-time attitude fault-tolerant controller. The method is mainly applied to unmanned aerial vehicle control occasions.

The invention relates to a quad-rotor unmanned aerial vehicle integral sliding mode control method based on an expansion state observer. On the basis of a dynamics model and a propeller model of a quad-rotor unmanned aerial vehicle, the integral sliding mode control rate is obtained through integral sliding mode control; and by adopting the expansion state observer, external interference on a system is estimated according to an input and an output of the quad-rotor unmanned aerial vehicle system to obtain an estimated value of the interference on the system, and then the integral sliding modecontrol rate is compensated. The method ensures the precision of tracking expected input of the quad-rotor unmanned aerial vehicle, and has a strong anti-interference capability.

The invention discloses a UAV adaptive tracking control algorithm based on a saturation limitated condition. The method comprises following steps of: first, building a non-linear, underactuated quad-rotor UAV model based on a Newton-Euler model, and realizing mathematization processing on the quad-rotor UAV model; then, based on an input saturation limited function model, building a system framework and selecting an input limited function; then, based on a sliding mode variable structure control method, realizing controlling and processing of a quad-rotor UAV position secondary system; and finally, based on an adaptive tracking control method, introducing active disturbance rejection control so as to process uncontrollable disturbance of the UAV, and realizing controlling and processing ofa quad-rotor UAV gesture secondary system. Under complex conditions that UAV input saturation is limited, and system disturbance is uncertain and uncontrollable, the method uses a dual closed-loop control model to adaptively track and control the position and gesture of the UAV, so as to enable the UAV to fly stably finally.

The invention discloses a quad-rotor UAV (unmanned aerial vehicle) formation fault tolerance method based on multi-UAV distributed control. The method comprises the steps as follows: constructing a failure power model of multiple quad-rotor UAVs; then, constructing a first sliding mode distributed formation controller and a second sliding mode formation controller on the basis of the normal formation process of the quad-rotor UAVs, and controlling positions and postures of the quad-rotor UAVs under the normal formation condition so that the quad-rotor UAVs can realize formation flying according to set tracks; finally, constructing a state observer, judging whether a failure occurs according to residuals between observed results and actual results in the formation process by the state observer, if yes, designing a self-adaptive distributed sliding mode formation controller to control each quad-rotor UAV to form according to the set tracks; otherwise, continuously performing controllingby the first sliding mode distributed formation controller and the second sliding mode formation controller. The formation of the quad-rotor UAVs can be controlled stably.

The invention relates to a quad-rotor aircraft nonlinear sliding mode pose control method based on an error exponential function. The invention design a quad-rotor unmanned aerial vehicle nonlinear sliding mode pose control method by using a nonlinear sliding mode control method in allusion to a quad-rotor unmanned aerial vehicle system containing a dynamic execution mechanism. The design of a sliding mode surface is to ensure quick and stable convergence of the system. In addition, the robustness and the tracking accuracy of the system can be improved by adopting a nonlinear function to design the sliding mode surface. The quad-rotor aircraft nonlinear sliding mode pose control method based on the error exponential function realize quick and stable control of the system.

The invention discloses a hybrid control based design method of a stability augmentation controller of a quad-rotor unmanned helicopter in the technical field of automatic control. The design method comprises the following steps of: setting a state variable and a state switching parameter of the quad-rotor unmanned helicopter; setting a height switching value, a roll angle switching value, a pitch angle switching value, a roll angle critical value and a pitch angle critical value of the quad-rotor unmanned helicopter; setting a discrete state set and a discrete event set; setting a discrete state transition condition of the quad-rotor unmanned helicopter; and judging the state of the quad-rotor unmanned helicopter and respectively designing a lifting controller, a stability controller, the stability augmentation controller and an out-of-control protection device according to the state of the quad-rotor unmanned helicopter. By using the design method, the stable flight of the unmanned helicopter under a complex condition can be ensured, the out-of-control condition can be effectively avoided, and the flight state of the helicopter can be improved.

The invention discloses a quad-rotor unmanned helicopter explicit prediction control method based on heuristic bionic loft optimization. The method comprises the following steps that 1, a quad-rotor unmanned helicopter model is built according to aerodynamics and kinematics, and a relation between the controlled quantity and the state quantity is given; 2, a loft optimization algorithm is initialized, and the number D of sampling points required in a linearization track is given; 3, a cost function is designed; 4, map compass factors are utilized for optimization; 5, loft optimization landmark operators are utilized for optimization; 6, sample target points optimized by a loft are obtained to construct a linear interpolation function; 7, the interpolation function optimized by the loft is applied to the model obtained in the first step; 8, simulation or experiments are performed to obtain related results and verification. According to the method, the control complex difficulty can be lowered, the problem that explicit prediction control has the high requirement for the track and is hard to apply is solved, the online optimization process is avoided, a large amount of time is saved, and the control cost is lowered.

The invention discloses an oil-drive variable-pitch quad-rotor unmanned aerial vehicle which comprises a power-transmission system, a rotor-operation system and a rack system. Both the rotor-operation system and the power-transmission system are fixed to the rack system. The oil-drive variable-pitch quad-rotor unmanned aerial vehicle mainly solves the problems that a conventional electric multi-rotor vehicle is poor in wind resistance and the like, the load is small, and the flight time is short and the problems that purchasing, using and maintaining cost is high and the use and maintenance technical doorsill is high due to complexity of the mechanical structure, the structural dynamic characteristic, the flight dynamic characteristic, the aerodynamic characteristic and a flight control system of a conventional helicopter.

The invention relates to an enhanced fast power reaching law sliding mode control method of a quad-rotor UAV system. The enhanced fast power reaching law sliding mode control method is designed for the quad-rotor UAV system by combining with a fast power reaching law sliding mode control method. The design of an enhanced fast power reaching law is used for ensuring a sliding mode of the system canreach a sliding mode surface more quickly, does not increase the chattering phenomenon of the system, and achieves fast and stable control of the system.

The invention relates to the field of unmanned aerial vehicles and flight control and discloses a miniaturized unmanned aerial vehicle positioning and navigation method based on a Beidou navigation system. The introduction of visual navigation, the position estimation accuracy and the robustness are improved. According to the concrete technical scheme provided by the invention, the miniaturized unmanned aerial vehicle positioning and navigation method based on the Beidou navigation system comprises the following steps: obtaining speed information of an unmanned aerial vehicle by use of an optical flow sensor installed at the bottom of the quad-rotor unmanned aerial vehicle, obtaining accelerated speed information by use of an airborne inertial navigation apparatus, obtaining speed information by use of an airborne visual system, and through combination with an original measurement value of the position of the Beidou system, obtaining estimation of the position and the speed through fusion filtering; and accordingly, through a nonlinear position control algorithm, realizing aerial vehicle position control. The method is mainly applied to unmanned aerial vehicle and flight control occasions.

The invention provides a quad-rotor unmanned aerial vehicle and a control method thereof. The quad-rotor unmanned aerial vehicle comprises a body and a main controller module and further comprises a navigation module, a sensor module, a communication module and a motor control module which are respectively connected with the main controller module, wherein the main controller module is used for comprehensively calculating the real-time flight attitude information fed back by the sensor module and the navigation module and the control information of the communication module and then outputting a motor control signal to control the motor control module. The quad-rotor unmanned aerial vehicle is advantaged in that automatic adaptation to change of the external environment can be realized to modulate flight parameters to realize the pre-determined control effect. According to the control method, the main controller module employs a control scheme combining a back-propagation artificial neural network with inertia term (BPNNI) neural network and based on weight adjustment with proportional integral derivative (PID) control to calculate an actual output control variable.

The invention discloses a quad-rotor unmanned aerial vehicle autonomous landing method based on visual positioning. In order to enable the quad-rotor unmanned aerial vehicle to autonomously and accurately land on a ground landing platform so as to carry out fixed protection, charging endurance and mobile carrying on the quad-rotor unmanned aerial vehicle, a visual identification mark composed of aregular triangle and concentric rings is designed, and a novel vision-based quad-rotor unmanned aerial vehicle autonomous landing method is provided based on the identification mark. In the first stage of the method, position parameters of an unmanned aerial vehicle and the center of an identification mark are calculated through a regular triangle of the identification mark; in the second stage,the position deviation and the yaw angle between the unmanned aerial vehicle and the center of the identification mark are determined through concentric rings and heading reference lines in the concentric rings, and finally attitude adjustment and autonomous landing of the unmanned aerial vehicle are completed. Through verification of a landing experiment of the unmanned aerial vehicle, the methodcan accurately extract sign features, calculate position information and angle information of the unmanned aerial vehicle relative to the identification sign in real time, and realize accurate landing.