518 results about "Backstepping" patented technology

The invention discloses a method in a boat control field and especially relates to the sliding mode-reverse step double loop trace tracking control method of an underactuated unmanned surface vehicle.The method comprises the following steps of firstly, establishing a three-degree-of-freedom motion mathematical model of the heading, the surging and the swaying of the unmanned surface vehicle; then, through an integrated pose sensor, measuring the current position information of the unmanned surface vehicle, combining the real-time position and the reference trace of the unmanned surface vehicle, calculating an error under a boat body coordinate system; and then, designing a kinematic loop trace tracking controller based on a backstepping method, and designing a dynamic loop trace trackingcontroller based on a sliding mode control algorithm. Through a sliding mode-reverse step double loop trace tracking controller, the trace tracking control of the unmanned surface vehicle Is realized,the unmanned surface vehicle can track a linear trace, and the stability and accuracy of unmanned surface vehicle navigation can be increased.

The invention provides an underactuated UUV plane trajectory tracking control method based on dynamic speed adjustment, relating to the motion control technology of an underactuated underwater unmanned vehicle. The invention aims to realize the precise tracking control of an underactuated UUV plane trajectory. The method comprises the steps of (1) a UUV obtains position and attitude information according to a current task, (2) position and attitude error variables are obtained by using the mathematical model of an underactuated UUV, (3) a method of defining a virtual speed error variable to calculate a virtual control rule, (4) combined with a biologically inspired model, the dynamic adjustment of a speed error is carried out, and (5) the control signal generated by a speed adjustment controller is deduced, and the underactuated UUV plane trajectory tracking control is realized. According to the method, the dynamic adjustment of the speed of the underactuated UUV can be carried out, a singular value when a first direction angle error is equal to 90 degrees in a traditional backstepping method is avoided, and the tracking of a circular trajectory in an external constant disturbance is realized.

The invention discloses a specific performance based consistency control method for multiple intelligent agents. The control method comprises that the intelligent agents as communication nodes establish a communication topology; neighbor node and self state information is obtained according to the communication topology; the state information includes the position and speed; a tracking error of aleader is calculated according to the state information; the specific performance of the tracking error is transformed via a design performance function, and a transformed error model is obtained; andaccording to the transformed error model, an event triggering adaptive controller of a follower is designed via a backstepping method and a dynamic surface technology, an event triggering mechanism is designed, and specific performance based consistency control for the intelligent agents is realized. A system can obtain expected transient performance and stable error in the control process rapidly and precisely, the communication cost among the intelligent agents can be reduced, the application range is wide, and the application value is high.

The invention provides a trajectory tracking method for a four-wheel-driven wheeled mobile robot. The method comprises the steps of firstly establishing a kinematic model, a dynamic model and a driving motor model of a system; then designing a kinematic controller for adjusting speed of the system according to a given reference trajectory based on the kinematic model; operating the kinematic controller for obtaining the anticipated torque of a motor according to the speed of a to-be-adjusted system based on the kinematic model; designing a driving motor controller for designing an appropriate driving voltage of the system for satisfying the anticipated torque of the motor based on the driving motor model; and finally performing trajectory tracking control on the four-wheel-driven wheeled mobile robot according to a backstepping robustness trajectory tracking control method. The trajectory tracking method according to the invention realizes a purpose of improving stability of a four-wheel-driven wheeled mobile robot control system in a complicated uncertain environment and furthermore improves system controlling effectiveness on the condition with uncertain factors.

The invention provides a fisheye image correcting method for image stitching. The method corrects two fisheye images partially overlapped with each other through a computer, and finds out a splicing angle of stitching caused by pitch angles during shooting between the two fisheye images by adopting an unique correction principle and utilizing matched pixels in the two fisheye images so as to obtain the pitching angle formed during the shooting of the two fisheye images through backstepping; and the method also avoids adverse impacts, such as inclination, ghosting, and the like, of errors of the pitch angles formed during the shooting on the panorama stitching of the fisheye images through pitching conversion mapping treatment, and has the advantages of better robustness and high accuracy in computation.

The invention belongs to the technical field of electromagnetic wave polarization detection, and particularly discloses an efficient microwave polarization detection device based on a photonic spin Hall effect. For the detection device, electromagnetic wave to be detected is decomposed into left-hand circularly polarized beam and right-hand circularly polarized beam through the efficient photonic spin Hall effect, the module values and phases of the left-hand circularly polarized beam and right-hand circularly polarized beam are respectively measured, and backstepping is carried out to obtain the polarization of the electromagnetic wave to be detected. The photonic spin Hall effect is realized through linear geometry Berry phase gradient of total-reflection type meta-surface with a spin structure. Compared with the traditional polarization detection manner (linear polarization loudspeakers opposite to each other are used for directly measuring x component and y component of electromagnetic wave), the efficient microwave polarization detection device has the advantages that higher convenience and quickness are achieved, the errors are few, and the stability is better. The operating frequency of the device is 10-14GHz, and the structure constants of meta-atoms are scaled in equal proportion or redesigned, so that the operating frequency can be applied to other operating frequency ranges.

The invention discloses a control method of a hypersonic vehicle orienting the uncertainty condition. The control method comprises the following steps that step S1, full state feedback linearization processing is performed on flight speed V and flight height h according to a hypersonic vehicle longitudinal dynamic equation so as to obtain a corresponding state equation; step S2, an anti-step sliding mode controller is designed according to the state equation, and the double exponential approximation law of the selected sliding mode surface is S<.>=-k<1>|S|<eta>sgn(S)-k<2>|S|<lambda>sgn(S), wherein k<1>>0, K<2>>2, eta>1 and 1>lambda>0 are parameters in the formula; and step S3, a test platform is established based on the anti-step sliding mode controller to perform performance simulation. According to the method, the double exponential sliding mode controller based on the backstepping method is adopted, and switching gain and the problem of buffeting existing in sliding mode control can be effectively reduced by the method.

The invention provides a welding microcell performance test based residual stress detection method, which comprises the following steps of: carrying out a micro-compression-shear test on a welding microcell so as to obtain a load-displacement curve of the welding microcell, establishing a 3D (three-dimensional) finite element model of a micro-compression-shear test process, and carrying out a finite element reverse backstepping method based on an improved Gurson model so as to obtain a true stress-strain relation of the welding microcell; computing the welding residual stress, wherein in the process of carrying out computing on a welding temperature field, the influence of the mechanical property of the welding microcell on the change of the temperature field is not considered; and after the welding temperature field is obtained, in the process of carrying out computing on a welding stress field, taking normal-temperature mechanical property parameters (when the temperature of a weldment is reduced according to the true stress-strain relation of the welding microcell) into a welding computing model, and then obtaining the welding residual stress through computing. The accuracy of the method disclosed by the invention is higher than that of a result obtained by using a residual stress computing method which is implemented through not considering the mechanical property of the welding microcell.

The invention discloses a rigid spacecraft performer multi-fault diagnosis and fault tolerance control method. According to the method, the kinetic and dynamic model of a rigid spacecraft attitude control system is put forward, a fault model for existing of both the performance failure fault and the deviation fault of a rigid spacecraft is established, and then a fault detection observer adopting the adaptive threshold technology and a fault estimation observer based on the adaptive technology are respectively established so that online real-time detection and estimation of the fault time and the concrete situation of the fault can be realized, and finally a backstepping sliding mode fault tolerance controller is designed according to fault information established by the fault estimation observer. Attitude stabilization control of the rigid spacecraft under the condition of the performer efficiency damage and the deviation fault can be realized, and the influence of external disturbance on the system and the observers can also be considered in the design process. Besides, the fault detection observer and the fault estimation observer can be independently designed so that the engineering application can be more easily implemented.

The invention provides a four-rotor aircraft sliding mode control method based on a nonlinear disturbance observer. The influence of system uncertainty and external disturbance of the four-rotor aircraft is considered, the method comprises the following steps: firstly, establishing a four-rotor dynamical model considering external disturbance and providing a nonlinear disturbance observer to estimate the actual value of the external disturbance; the invention aims to ensure the stability of a four-rotor aircraft, four-rotor dynamics is decomposed into an attitude subsystem and a position subsystem according to the design thought of double rings, controllers are designed for the two subsystems respectively, the nonsingular fast terminal sliding mode controller designed for the inner ring can ensure fast convergence of the attitude, backstepping and the nonsingular fast terminal sliding mode are combined and applied to an outer ring, the tracking performance is guaranteed, and the methodhas good tracking performance and high robustness for the four-rotor aircraft with system uncertainty and external disturbance.

The invention discloses a method for measuring plantar pressure. The method mainly aims at reducing cost for accurate monitoring of plantar pressure information. A plantar pressure measurement device with lots of sensing points is first utilized for measuring the plantar pressure information; a model is established according to the information and a modeling method put forwards in the method and plantar pressure models; the model can present differences between different persons; finally, a plantar pressure measurement device with few sensing points is used for monitoring the plantar pressure information of a measurer; the plantar pressure information of various position points on the planta pedis is obtained through model backstepping reduction, and therefore complete and accurate plantar pressure information can be obtained through the simple devices. A layout of sensor arrays at different intervals is used for the optimized measurement device with lots of sensing points, and the optimized measurement device with few sensing points is obtained through embeddable structures of sensor units. Two kinds of models are used as the plantar pressure models and include a neural network model and an interpolation model relevant to distance.

The invention discloses a multi-joint industrial mechanical arm backstepping finite time sliding mode control method considering system sum disturbance. The multi-joint industrial mechanical arm backstepping finite time sliding mode control method includes the steps: establishing a multi-joint industrial mechanical arm system model; designing a system three-order expansion state observer for accurately estimating the system sum disturbance item; based on system sum disturbance estimation, and for the system model (2), performing system backstepping finite time sliding mode control rule designby combining the backstepping design idea and the finite time sliding mode technology. The multi-joint industrial mechanical arm backstepping finite time sliding mode control method has strong robustness for nondeterminacy factors, such as model parameter perturbation and external bounded disturbance, and can guarantee fast and stable finite time tracking control of the desired trajectory of the system, so that the designed control method is convenient for application in practical engineering.

The invention provides a flexible satellite neural network backstepping sliding mode attitude control method, relates to a flexible spacecraft attitude control method, and aims at solving a problem of perturbation generated by plate flexible vibration and antenna rotation and a problem of enhancement of steady state precision and stability of existing attitude control methods. According to the method, a flexible satellite attitude kinetic model is established firstly according to a spacecraft, and then a model formula is processed; a sliding mode attitude controller (which is expressed in the specification) based on a backstepping method is designed; then an RBF neural network approach (eta+htau)sgn(sigma) is adopted; the controller (which is expressed in the specification) is designed; and finally a complete attitude controller (which is expressed in the specification) is obtained. A three-axis attitude controller is designed respectively according to the aforementioned process. The flexible satellite neural network backstepping sliding mode attitude control method is suitable for the field of flexible spacecraft attitude control.

The invention discloses a control method of a driving system of a permanent magnet synchronous motor of an electrical automobile considering iron loss, and provides a control method of a driving system of a permanent magnetic synchronous motor considering iron loss based on a self-adaptive fuzzy backstepping method, which solves the non-linear problem of the power driving and control system of the motor of the electrical automobile, enables the motor to quickly reach the stable running state and is more suitable for the control objects requiring quick dynamic response, such as the driving system of the electrical automobile. The control rules u[d] and u[q] only adopt one self-adaptive parameter theta, so as to reduce the calculation amount. The method has the advantages that the problem of position tracking and control of the permanent magnet synchronous motor considering the iron loss under the conditions of orienting to the site and having undetermined parameter and load torque disturbance is solved; the fuzzy logic system is used for approximating to the unknown non-linear item, and the self-adaptive fuzzy backstepping method is used for enabling the tracking error to approximate to 0; the more accurate control precision is reached, and the ideal position tracking and control effect is ensured.

The present invention discloses an electric vehicle asynchronous motor fuzzy adaptive dynamic surface control method with the consideration of an iron loss. According to the control method, by using the nonlinear function in a fuzzy logic system approximation system, an adaptive backstepping method is used to design a controller, and the dynamic surface control technology and a fuzzy adaptive method are combined. Through introducing a first-order low-pass filter, a 'computing explosion' problem caused by continuous derivation in traditional backstepping control is successfully overcome. In addition, control signals uqs and uds only exist in an adaptive parameter Theta<^>, and the amount of computation is reduced. Through fuzzy adaptive dynamic surface control method adjustment, motor operation can rapidly reaches a stable state and is more suitable for a control object with the need of rapid dynamic response like an electric vehicle driving system, a simulation result shows that the influence of parameter uncertainty is overcome and an ideal control effect is ensured according to the control method, and the rapid and stable response of rotation speed is realized.

The invention discloses an electronic throttle valve adaptive backstepping control method based on a Romberg sliding-mode observer, and relates to the technical field of automobile electronic control. Firstly, in order to solve the problem that the change of the opening degree of an electronic throttle valve can not be measured, the change is estimated through the Romberg sliding-mode observer and based on the electronic throttle valve state equation; secondly, approaching is conducted on the nonlinear unknown quantity-gear clearance torque through the approaching characteristic of an RBF neural network; finally, a control law, an RBF network weight renewing law and an interference adaptive law are designed based on the Lyapunov stability theory and through combination with the nonlinear backstepping control method. By means of the method, the problem that nonlinear factors and some parameters easily change over time during electronic throttle valve control can be well solved, and the control effect and dynamic response performance are further improved.

The invention discloses a four-rotor UAV flight control method based on a fractional order power switching law. A whole controller is of a backstepping control structure, a second-order nonlinear system of a quadrotor UAV is split into two subsystems, control laws that satisfy Lyapunov's stability theory are constructed, and the two subsystems are in series connection through a virtual intermediate control variable to form the complete controller, so that the controller can well adapt to the nonlinearity of the system and have good integrity. At the same time, in order to enhance the anti-disturbance capability and robustness of the controller, in the second backstepping design, the controlled variable is subjected to the sliding mode control design, which introduces the high disturbance resistance and high robustness of the sliding mode control. .

The invention discloses an aircraft track inclination angle control method based on a minimum parameter studying method. The aircraft track inclination angle control method comprises the following four steps; 1, analyzing and modeling a longitudinal aircraft control system; 2, controlling and designing a neural network dynamic surface based on the minimum parameter studying method; 3, testing tracking performance and regulating parameters; and 4, ending the design. In the aircraft track inclination angle control method, for a longitudinal aircraft model, an unknown function of a neural network approximating system is established; the number of parameters to be estimated is reduced by the minimum parameter studying method; the virtual control is gradually designed; a first-order low-pass filter is introduced in each step; and the neural network dynamic surface control is ultimately deduced. A differential explosion phenomenon in a reversal deduction control is overcome, and the rapid and accurate tracking of the aircraft track inclination angle on a preset track can be realized.

Provided is a four-rotor aircraft output-limited backstepping control method based on an integral sliding mode obstacle Lyapunov function. For the dynamic system of a four-rotor aircraft, an integralsliding mode obstacle Lyapunov function is selected, and a four-rotor aircraft output-limited backstepping control method based on the integral sliding mode obstacle Lyapunov function is designed. Theintegral sliding mode obstacle Lyapunov function is designed in order to ensure that the output of the system is limited within a certain range, avoid too large overshoot and reduce the time of arrival. Therefore, the dynamic response performance of the four-rotor aircraft system is improved. The invention provides a four-rotor aircraft output-limited backstepping control method based on an integral sliding mode obstacle Lyapunov function, which enables the system to have a good dynamic response process.