247 results about "Observer based" patented technology

A Presence Server receives presence information associated with a Presentity, wherein the presence information comprises one or more presence attributes and the Presentity is associated with a Presence Source and a first Watcher. The Presence Server further receives a request from a second Watcher to view a presence attribute of the one or more presence attributes. The Presence Server may further receive a message from the first Watcher specifying a desire to be notified of who is watching the Presentity, presence attributes being filtered, and/or throttling or deferring of presence attribute updates being implemented by the Presence Server. The Presence Server conveys to the first Watcher watcher notification information that informs of Watchers watching the Presentity, what is being watched, presence attributes being filtered, and/or throttling or deferring of presence attribute updates. The Presentity then determines whether to publish a presence attribute update based on the watcher notification information.

Methods, systems, and apparatuses are described for automatic adjustment of display systems based on ambient light intensity. Ambient light intensity of a viewing environment is determined from a location of a display system or from a location separate from the display system. Ambient light information may be collected using light sensor(s) or image sensor(s) of a camera or other imaging capturing device. When a viewer is present, ambient light intensity may be determined from a perspective of the viewer. The determined light intensity information is used to determine a white balance level. A characteristic of the display system is adjusted based on the determined white balance level.

Improved methods and systems for controlling hydraulically or electrically actuated anti-lock brake systems (ABS) on air and land vehicles requiring only measurement of wheel angular speed although brake torque measurements can also be employed if available. A sliding mode observer (SMO) based estimate of net or different wheel torque (road/tire torque minus applied brake torque) derived from the measured wheel speed is compared to a threshold differential wheel torque derived as a function of a “skid signal” also based on wheel speed only to generate a braking control signal. The braking control signal can be employed to rapidly and fully applying and releasing the brakes in a binary on-off manner and, as an additional option, possibly modulating the maximum available brake hydraulic pressure or electrical current when the brakes are in the “on” state in a continuous manner. In the case of the basic on-off component of braking, the brakes are released when the estimate of differential wheel torque is less than the threshold differential wheel torque (i.e. for relatively high values of brake torque), and the brakes are applied fully when the estimate of differential wheel torque is greater than or equal to the threshold differential wheel torque. For aircraft landing gear applications, a fore-aft accelerometer mounted on the landing gear can be used to suppress nonlinear gear displacement oscillations commonly called gear walk in the direction of wheel roll.

The invention discloses an unposition sensor for a permanent magnet linear motor. Before a motor starts, a designated trigger signal is inputted into an inverter, a corresponding line inductance value is solved, the calculation is realized by combining the existing inductive parameters of the motor for preliminarily obtaining an initial position of a linear servo motor and then high-frequency voltage is immediately introduced to judge the direction of a magnetic pole of the rotor; after the motor starts, the position of the rotor is detected at the low-speed phase in real time by a method of combining the injection of the high-frequency voltage with the repetition of a controller; position information of the rotor is acquired at the middle-high speed phases in real time by a method of combining a sliding-mode observer based on an extended counter electromotive force model with a saturation function algorithm. According to the unposition sensor disclosed by the invention, an initial position detection method, a rotating high-frequency injection method, repeated control and the sliding-mode observer are combined together, so that the position information of the linear servo motor can be accurately and effectively detected, the defects caused by the existence of a mechanical sensor are overcome and the reliability of the system is improved.

The invention relates to an AR implementation method and system based on the positioning of a visual angle of an observer, and the method comprises the steps: obtaining the position and posture of the observer located in a real scene, and giving the position and posture to a virtual camera; transmitting and the position and posture to a rendering center for rendering, and obtaining a three-dimensional virtual scene; transmitting the three-dimensional virtual scene to display equipment worn by the observer, carrying out the superposing of the three-dimensional virtual scene and the real scene, and displaying the superposed scene; and carrying out the matching of a real object in the real scene and a virtual object in the three-dimensional virtual scene. The method achieves the fusion and display of the real world and a virtual world, employs the rendering center in a server for rendering, enables the rendering process to be integrated in the server, achieves no constraint on the size of the real scene and the complexity, is strong in rendering capability, is high in applicability, and is wide in application range.

Automotive electronic control unit programmed to realtime estimate either or both of vehicle mass and road slope, wherein; a. road slope, is estimated; a1. when vehicle is considered stopped based on an accelerometer signal indicative of vehicle acceleration, wherein the vehicle is considered stopped in the presence of substantially zero values of a speed signal indicative of vehicle speed, and a2. when vehicle is in rectilinear and curvilinear motion by implementing a road slope observer based on a linear Kalman filter, which is designed to: a21. operate based on signals indicative of vehicle speed and acceleration, and a22. compensate for accelerometric disturbances due to; a221. vehicle static pitch resulting from vehicle load distribution, and a222. vehicle dynamic pitch due to acceleration to which vehicle is subjected during motion, and a223. accelerometric disturbance components due to vehicle lateral dynamics; b. vehicle mass is estimated: b1. when vehicle is in motion, and b2. based on a recursive least square algorithm with forgetting factor, and b3. based on an accelerometric signal indicative of vehicle acceleration, on a vehicle speed signal, and other signals representing a vehicle propulsive/resistive torque, and b4. at different low gears, to provide a mass estimation and an associated variance for each gear, and b5. based on mass estimations and corresponding variances for each gear, and b6. compensating for accelerometer disturbances due to: b61, vehicle dynamic pitch; and b62. accelerometrie disturbance components due to vehicle lateral dynamics; and b7. minimizing uncertainties on propulsive/resistive torque due to gear efficiency and roiling resistance.

Based on a neural network technology and an instruction filtering inversion method, the invention discloses a robust fault tolerance control system design structure based on instruction filtering inversion. Firstly, a mathematical model of an NSV attitude control system is given out, uncertainties and external disturbance caused by modeling errors are considered based on the mathematical model, a state equation of the NSV attitude control system under the fault of a control surface is also considered. The method mainly includes the two design parts including design of an auxiliary system and design of a controller based on the auxiliary system. The auxiliary system is introduced into the neural network to ensure robustness of the auxiliary system, and stability of a closed-loop system is strictly proved through Lyapunov theorem. Meanwhile, simulation is carried out on an attitude control system of a corresponding air vehicle, and a result shows that the method enables the uncertain flight control system with the external disturbance to have the ideal fault tolerance tracking performance under damage to the control surface.

A system and methodology for control of a switched reluctance electric machine comprising: a switched reluctance electric machine including a sensor generating and transmitting a sensor signal indicative of an operating characteristic; a controller operatively coupled to the switched reluctance motor and the sensor; and the controller executing a method. The method comprises: probing a selected diagnostic phase with a pulse injection process; measuring an actual operating characteristic of the switched reluctance electric machine; computing an inductance based on the actual operating characteristic and correlating the inductance with a position to formulate an estimated position; modeling the switched reluctance electric machine to formulate an observer-based estimated position; selecting at one of the estimated position, the observer-based estimated position, and a combination thereof to formulate a selected position of the switched reluctance machine; and controlling said switched reluctance machine based on said selected position and a command.

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 discloses a brushless double-fed wind driven generator decoupling method based on an active-disturbance-rejection control (ADRC) technology. Aiming at problems of the structural complexity and convertibility along with environmental of a brushless double-fed motor, poor application of the traditional PID control in BDFM, and the like, the invention provides an expand observer-based non-linear PID control-ADRC method to achieve decoupling control on the active power and reactive power of a wind driven generating system. In the method, torque T of a wind turbine as well as the active power and the reactive power at a stator side are respectively used as quantities of sate to be input to form nonlinear and coupling items which are considered as interior disturbance quantities of ADRC, a reference quantity xref is set in a differential-tracker, and nonlinear feedback control is formed through configuration. An NLSEF utilizes the error between the input of a TD and the input of an ESO to generate a control quantity so that a mathematical model of a generator can obtain rotate speed and flux linkage subsystems after nonlinear state feedback is carried out so as to achieve the complete decoupling of the two subsystems in the dynamic process.

The invention relates to the quadrotor unmanned aerial vehicle fault-tolerant control, and aims to realize attitude stability under the condition of an actuator fault of a quadrotor unmanned aerial vehicle. The technical scheme adopted by the invention is that an observer-based quadrotor unmanned aerial vehicle fault-tolerant control method includes the following steps: first defining an inertia coordinate system {I}, a body coordinate system {B} and a target coordinate system {Bd}, and through analysis of an action principle of the actuator on the quadrotor unmanned aerial vehicle, an unknown diagonal matrix is utilized to represent influence of an actuator fault on kinetic characteristics of the quadrotor unmanned aerial vehicle, and a nonlinear kinetic model when a fault occurs in the quadrotor unmanned aerial vehicle actuator is obtained; a unit quaternion-based attitude representation method is adopted; and an observer technology based on an immersion-invariant set method is adopted to observe the actuator. The observer-based quadrotor unmanned aerial vehicle fault-tolerant control method provided by the invention is mainly applied to quadrotor unmanned aerial vehicle design and control occasions.

A reconfigurable mechanical arm decentralized control system and control method adopting position measuring belong to the field of robot control systems and control algorithms, and aim to solve the problems existing traditional reconfigurable mechanical arm control systems and methods thereof. The control method comprises the steps of initializing a system, detecting a reading of an incremental encoder to obtain position measuring information, and establishing a non-linear speed observer based on the information; according to the established non-linear speed observer, establishing a disturbance observation model; adopting an observation value obtaining a joint speed and a joint torque to establish a reconfigurable mechanical arm system dynamics model; by a given joint speed observer, a torque observer, expected dynamics information and the system dynamics model, adopting dynamics information of local joints to design a decentralized controller, compensating the modeling errors containing model determining items and friction and coupling items among joints, and inhibiting buffeting of the controller and enabling a mechanical arm joint to precisely trace an expected track.

The invention discloses a discrete variable structure observer-based lithium battery SOC (state of charge) estimation method. The method includes the following steps that: a rapid calibration test is performed on a lithium battery, a relation curve of SOC and open-circuit voltage (OCV) is obtained; a lithium battery discrete state space model for SOC estimation is established; a pulse discharge test is performed on the lithium battery, the parameters of the lithium battery model are identified; the terminal voltage and charge-discharge current of the lithium battery under a real-time collection condition are obtained; and a discrete variable structure observer is constructed to estimate the SOC of the lithium battery accurately. The method not only has a good SOC estimation effect, but also can ensure convergence strictly, and exhibits strong robustness to lithium battery modeling error, internal parameter perturbation and external disturbance.

The invention discloses a method for asynchronous motor rotor flux linkage observation and rotation speed identification, which comprises the following steps of: according to stator voltage and current signals measured in real time, observing to obtain a rotor flux linkage through a sliding mode observer based on a super-twisting theory and using the rotor flux linkage as a reference value; using a rotor flux linkage calculated according to a rotor flux linkage current model as an adjustable value; constructing a model reference self-adaptive system (MRAS) based on the rotor flux linkages; and identifying the asynchronous motor rotation speed through the self-adaptive law. The rotation speed identification method provided by the invention has high robustness for the variation of stator resistance, and can provide accurate rotor flux linkages and rotation speed values, thereby being especially suitable for an asynchronous motor vector control system.

The invention discloses an airplane rotation actuator drive unit adaptive fault detection, isolation and confidences assessment method. Firstly, in dependence on the structure of a rotation actuator drive unit, establishing a two-stage observer based on a radial basis function (RBF) nerve network, wherein a first stage RBF nerve network observer is used for estimating system desired output values and generating residual errors, and a second stage RBF nerve network observer is used for generating adaptive threshold values; then performing fault isolation based on output information of the observer; training a self-organizing mapping (SOM) nerve network by utilizing residual errors under a normal state; and finally utilizing residual errors to be detected and assessed as input of the SOM nerve network and performing normalization processing to obtain confidences values (CVs) indexes between 0 and 1. The airplane rotation actuator drive unit adaptive fault detection, isolation and confidences assessment method has high practical engineering application values.

The invention discloses a PMSM rotor position detection device and method based on an improved sliding-mode observer. A second-order generalized integration method is employed instead of a low pass filter to process a counterelectromotive force signal; an equivalent counterelectromotive force signal is observed through the improved sliding-mode observer based on a sigmoid function, buffeting of equivalent counterelectromotive force is inhibited through the second-order generalized integration method, phase lag caused by the low pass filter is avoided, a normalized quadrature phase locked loop is employed to estimate a rotor position signal according to the estimation counterelectromotive force signal, and the inhibition effect on each harmonic contained in the counterelectromotive force signal can be realized through resonance of the improved sliding-mode observer at the fundamental frequency. The method is advantaged in that the structure of the improved sliding-mode observer is simple, the observed counterelectromotive force signal is relatively accurate, and the high-precision rotor position information can be acquired.

The invention discloses an observer-based intelligent dual-integral sliding-mode control method for an electronic throttle valve. The method comprises the following steps: adopting an extended state observer, carrying out quantity x2 estimation on the opening change of the throttle valve according to the actual opening theta (x1) of the throttle valve, and obtaining the estimated value x2 of the opening change quantity of the throttle valve; combining sliding-mode control with a neural network through the Lyapunov stability theorem to obtain an intelligent dual-integral sliding-mode control law and an adaptive disturbance law, and carrying out control on the opening of the electronic throttle value and compensation on disturbance; carrying out adaptive design on the parameters of an intelligent dual-integral sliding-mode controller through a BP neural network, wherein the inputs of the BP neural network are the error e and error change e of the actual opening of the throttle valve and the expected opening of the throttle valve, and the outputs of the BP neural network are respectively taken as control gains kd, kp and ki; outputting the control input voltage u through the intelligent dual-integral sliding-mode controller to control a direct-current motor of the electronic throttle valve for controlling the opening of the electronic throttle valve. The method guarantees the precision of the electronic throttle valve for tracking expected input.

The invention discloses a novel five-phase fault tolerant permanent magnet motor sensorless control method based on specific load. A novel back emf observer based on an active disturbance rejection observer is designed on a basis of a load provided by a motor. The state equation of the motor in a static two-phase coordinate system is used as a new control system, and the back emf of the motor is used as control quantity. The active disturbance rejection observer is used to observe a characteristic of alternating current quantity, and the back emf of the motor in the two-phase static coordinate system is observed, and finally, a phase-locked loop observer is used to acquire the rotating speed and the rotor position angle of the motor. By using the novel back emf observer provided by the invention, use of filters is prevented by parameter selection, and the operation bandwidth of the system and the precision of the estimated position angle are improved, and therefore the reliable operation of the five-phase fault tolerant permanent magnet motor sensorless system is realized.