454 results about "Error feedback" patented technology

An articulated instrument is controllably movable between areas of different work space limits, such as when it is extendable out of and retractable into a guide tube. To avoid abrupt transitions in joint actuations as the joint moves between areas of different work space limits, a controller limits error feedback used to control its movement. To provide smooth joint control as the instrument moves between areas of different work space limits, the controller imposes barrier and ratcheting constraints on each directly actuatable joint of the instrument when the joint is commanded to cross between areas of different work space limits.

A method of filling in a form comprising using a digital pen to enter data into data entry areas of the form (64), and providing error feedback to the user (69) contemporaneously with filling in the form, said error feedback being indicative of the user entering a non-allowable entry in said data entry area.

A power converter including a hardware efficient control loop architecture. Error detection circuitry may generate an error signal based on the difference between a power converter output voltage and a reference voltage. An oversampling ADC may digitize the error signal. The transfer function associated with the ADC may include quantization levels spaced at non-uniform intervals away from a center code. A digital filter may calculate the average of the digitized error signal. A nonlinear requantizer may reduce the number of codes corresponding to the output of the digital filter. A proportional integral derivative (PID) unit may multiply the output of the nonlinear requantizer by PID coefficients to generate a PID duty cycle command, and a gain compensation unit may dynamically adjust the PID coefficients to maintain a constant control loop gain. A noise-shaped truncation unit including a multi-level error-feedback delta sigma modulator may reduce the resolution of the PID duty cycle command.

The invention relates to a PMSM servo system control method based on fuzzy and active disturbance rejection control. A position signal is given by a differential tracker to arrange a transition process so that the contradiction between rapidness and overshoot of a system is solved, and uncertainty, friction torques and external disturbance due to modeling errors of the system are observed via an expansion state observer; according to the error between the differentials generated by the differential tracker and state variation generated by the expansion state observer, a fuzzy inference rule is obtained with application of experimental experience of technical staff, so that a fuzzy rule control table of an error proportion coefficient, a differential coefficient and an integration coefficient is established; accurate control amount is obtained after de-fuzzification, so that parameter self-adaptive adjustment of a nonlinear error feedback control law is realized; and compensation amounts of the nonlinear error feedback control law and the expansion state observer to the total disturbance forms the control amount, thereby realizing optimal control for an controlled object. The method of the invention improves both tracking precision and disturbance rejection capability of the system.

The invention discloses a method and a device for controlling speed of a permanent-magnet synchronous motor. The method includes that an active-disturbance-rejection control technology is adopted for a speed ring, speed setting and a speed detection value are taken as input of a first-order active-disturbance-rejection controller, a tracking differentiator reasonably arranges a transition process, an extended state observer observes an actual value of rotating speed of the motor, estimates total disturbance of a system and acquires output of the speed ring through a nonlinear state error feedback control ratio, a load torque observer is designed through detection values of a current and the speed, and observed load torque through output of a feedforward controller and the active-disturbance-rejection controller is taken as reference input of a quadrature-axis current. The method carries forward characteristics of overshoot freeness, high disturbance rejection capacity, good robustness and the like of the permanent-magnet synchronous motor in speed control in the active-disturbance-rejection control technology, and compensation is performed on the problem of load disturbance, so that the problem of fluctuation of the rotating speed under the circumstance of load disturbance is improved.

A analog-to-digital converters and second order noise shaping systems are presented for providing a noise shaped analog feedback signal to a A/D converter in an analog-to-digital conversion system. The noise shaping system comprises a first order integrator having a single amplifier, and a digital error feedback system comprising a digital signal processing system, in which the digital error feedback system provides an analog feedback signal to the A/D converter with second order noise shaping with respect to a quantization error associated with the A/D converter.

The invention discloses a structure and a design method of an improved active-disturbance-rejection position controller for a direct current (DC) motor; the DC motor is taken as a controlled object, and an output position signal is taken as a controlled variable; the controller mainly consists of four parts, i.e., a tracking differentiator, a nonlinear state error feedback part, an extended state observer and a disturbance compensation part. The improved active-disturbance-rejection position controller is mainly used to improve a fal function in a nonlinear function in the extended state observer, and the fal function is used to determine the tracking performance of the extended state observer and the controller; the concrete improvement measure is adding a linear feedback area into non-linear feedback; therefore, the problem that in the traditional method, timely control cannot be realized when the system error is too large and the gain is too low can be solved on the basis of guaranteeing system stability. By comparing simulation lines obtained before and after the improvement for the controller, the structure and the design method which are provided by the invention are proved to accelerate the output signal response speed under the condition that the position error of the DC motor is larger, thus improving the integral control performance of a system.

The invention provides a multi-line array laser three-dimensional scanning system and method. Accurate synchronism and logic control of the multi-line array laser three-dimensional scanning system can be achieved through an FPGA, a line laser unit array serves as a projection pattern light source, trigger signals are sent to a stereoscopic vision image sensor and the line laser unit array through the FPGA, an upper computer receives image pairs shot by the stereoscopic vision image sensor, laser line array patterns in the image pairs are subjected to encoding, decoding and three-dimensional reconstruction, three-dimensional reconstruction and matching alignment of three-dimensional feature points between different moments are conducted on surface feature points of an object to be measured, and matching calculation is subjected to prediction and error correction through an optical tracking technology. The system and method are used for registration and connection of time domain laser three-dimensional scanning data, meanwhile, measuring error grades are evaluated in real time and fed back to an error feedback controller for adjusting indication, and therefore laser three-dimensional scanning with low cost and high efficiency, reliability and accuracy is completed accordingly.

A read channel in that reads data from a magnetic storage media. An analog signal produced by passing a read head over magnetic storage media is amplified to match the range of an analog to digital converter (ADC) range. A baseline adjustment is performed on the amplified analog signal to center the amplified analog signal to a midscale of the ADC, which may be based on an error feedback signal and/or a decision feedback signal. Read channel compensation may then be performed after the baseline adjustment has been applied. The read channel compensated analog signal is sampled with the ADC to produce a digital signal. This digital signal may be filtered and a bit sequence may then be detected from the filtered digital signal. The EFB signal and/or the DFB signal may be produced in the digital domain based on the digital signal and the detected bit sequences.

The present invention relates to a crosstalk estimation device for estimating crosstalk between communication lines in a precoding group. The crosstalk estimation device comprises transmission means for transmitting a pilot sequence and reception means for receiving error feedback on one or more communication lines in the precoding group. The crosstalk estimation device further comprises crosstalk estimation means for combining the pilot sequence with the error feedback in order to obtain a crosstalk estimation between the communication lines. The device further comprises selection means for selecting a subset of one or more communication lines from the precoding group. The transmission means are adapted to transmit the pilot sequence only on the subset.

A delta sigma modulator based analog to digital converter is presented, having a first quantizer and a digital error feedback system comprising a second quantizer and a digital bandpass noise shaping system. The second quantizer provides a second quantized output to the noise shaping system according to the first quantized output, the system analog input, and the noise shaped feedback signal. The digital noise shaping system provides a feedback signal to the first quantizer according to the second quantized output, where the feedback signal is bandpass noise shaped with respect to a quantization error of the first quantizer.

A tri-rotor attitude control method based on an auto-disturbance rejection controller (ADRC) includes determining a mathematic model of a tri-rotor aircraft, determining input-output variables suitable for the model, tracking differentiator design, building an expansion state observer, and selecting a non-linear error feedback rate. A core control panel based on Atmega 2560 serves as an execution module, the motor is powered through a drive circuit, and the PWM wave can be adjusted according to the rotating speed of the motor. An inertial navigation module is formed by a tri-shaft gyroscope sensor, an accelerometer, a GPS and a digital compass, and a power supply module provides appropriate voltage to power each module through a power distribution module. For a tri-rotor aircraft model, parameters of all modules are adjusted to achieve excellent effects for auto-disturbance rejection control method. Module design and parameter adjustment of all modules allow three rotors to retain an excellent flying state through an auto-disturbance rejection control system.

The invention discloses a switching control method of a linear/nonlinear active disturbance rejection control system. The method comprises the step of establishing an active disturbance rejection control system, the step of performing linear/nonlinear switching on an extended state observer and the step of carrying out linear/nonlinear switching on a state error feedback control law. The method provided by the invention has the following advantages: the method has a higher anti-interference capability and higher control precision; the stability is irrelevant with an initial state; and a parameter setting method provided by the invention is integrated with the advantages of both a "bandwidth method" and an "experience method", influences of sampling step length, noise and the like are also taken into consideration, and the problems of deteriorating tracking performance and control performance which are caused by too large disturbance amplitude do not have to be considered.

The invention discloses an efficient super-resolution method based on a deep back projection network. The method comprises the following steps: (1) obtaining a total training set and a test set; (2) preprocessing the total training set to complete data enhancement; (3) scaling the images in the total training set at different scales; and (4) image super-resolution reconstruction is realized basedon the convolutional neural network, and the convolutional neural network totally comprises 27 convolutional layers and specifically comprises three parts of feature extraction, error back projectionand image reconstruction. The combination of the group convolution and the 1 * 1 convolution is used for replacing the traditional convolution to redesign the iteration submodule, and the strategy caneffectively reduce the model parameter quantity and improve the model efficiency; Each iteration sub-module comprises an error feedback mechanism, so that error correction can be carried out in time;in addition, a channel weighting module is introduced, so that the model efficiency can be further improved.

The invention relates to the information technology field of radio electronics and telecommunication technology, and relates to an aggregate of wireless enhancement technology of high-speed data transmission in the wireless communication field, in particular to an all-in-one feedback retransmission method based on fountain code mainly applied to wireless channel data transmission high-speed data service in a general mobile communication system. The method utilizes the ratioless channel coding principle of the fountain code, improves the existing mixed bit error feedback retransmission HARQ method and data coding mode in a wireless link, and mainly solves the relevant technical problems of how to utilize unique fountain code series to carry out the algorithm flow of coding and decoding foreach data block. The method has the beneficial effects that the feedback retransmission method and relevant fountain code design scheme can lead the data throughput of the wireless link to be improvedby 110% compared with the prior art, and the method has higher efficiency when the data blocks segmented in each group is more or the initial transmission groups sharing the same retransmission groupare more.

The invention provides a ship track active-disturbance-rejection control method based on the slip form of a multi-modal nonsingular terminal. The method includes the steps of constructing an expectedship heading equation according to navigational parameters of a ship, deducing a discretization nonlinear structural model of a two-order differentiator, processing expected ship heading signals in the expected ship heading equation to obtain expected ship heading differential signals required for controlling the rudder angle by the control law, obtaining the output rudder angle on the basis of the switchable error feedback control law, constructing an expanded state observer in combination with the error feedback control law, tracking the output deviation according to the expanded state observer, estimating the heading angle and inner and outer disturbance errors controlled by the control law, and feeding the heading angle and the inner and outer disturbance errors back into the control law. By improving the expanded state observer, a linear function and a nonlinear function can be switched in real time; the switchable segmented slip form face is designed; through the segmented slip form face, the switchable error feedback control law is designed, and the under-actuated ship track control is well realized.

The invention provides a multi-wire array-laser three-dimensional scanning system and a multi-wire array-laser three-dimensional scanning method. In the system, through a programmable gate array FPGA, accurate synchronization and logic control of the multi-wire array-laser three-dimensional scanning system can be realized. A wire laser array is used as a projection pattern light source. Through the FPGA, trigger signals are sent to a stereo vision image sensor, an inertial sensor and the wire laser array. An upper computer receives an image pair shot by the stereo vision image sensor, and carries out coding, decoding and three-dimensional reconstruction on a laser wire array pattern in the image pair. The three-dimensional reconstruction and three-dimensional characteristic point matching and aligning are performed on a characteristic point of a measured object surface. A mixing sensing positioning technology is used to carry out prediction and error correction on matching calculation, which is used for registration and splicing of time-domain-laser three-dimensional scanning data. Simultaneously, measurement error grade assessment is performed in real time and an assessment result is fed back to an error feedback controller so that an adjusting indication is obtained. Therefore, laser three-dimensional scanning with low cost, high efficiency, high reliability and high precision is realized.

The invention belongs to the technical field of navigation posture measurement, and provides a posture measuring method and terminal equipment. The posture measuring method comprises the following steps: initializing state quantity of Kalman filtering according to a gyroscope, an accelerometer, a magnetometer or external course information; constructing state equations of the Kalman filtering, andpredicting posture information of a carrier and errors of sensors; constructing measuring equations, outputting an roll angle and a pitch angle of horizontal posture with the accelerometer, performing measuring and updating, and adjusting a measuring variance matrix in a self-adapting manner according to the motion condition of the carrier; constructing measuring equations of a course angle, performing measuring and updating on the course of an AHRS system through the magnetometer or the external heading information; according to the output of the accelerometer, determining the motion condition of the carrier, and determining a feedback strategy of null bias error of the gyroscope. According to the posture measuring method disclosed by the invention, original output of the gyroscope is amended by the estimated null bias error feedback of the gyroscope, the problem that the conventional AHRS system cannot provide accurate and reliable information for resolution of the posture of the carrier can be solved.

The invention provides an aero-engine active fault-tolerant control method based on an error interval observer, and belongs to the technical field of aviation control. The method comprises the steps that an aero-engine tracks the state and the output of a reference model through an error feedback controller; an aero-engine control system with a disturbance signal and with an actuator fault and a sensor fault is compensated through a virtual sensor and a virtual actuator; the error between an aero-engine fault system and the reference model of the aero-engine fault system is observed through the error interval observer, and the error is fed back to the error feedback controller; and finally, the difference between the reference model output of the fault system and the virtual actuator output is used as a control signal to achieve active fault-tolerant control of the aero-engine. According to the method, when the actuator and the sensor of the aero-engine breaks down, even the disturbance signal exists, the system can be ensured to operate in a desired state without changing the controller, so that the system has good fault-tolerant capability and anti-interference capability.

This invention presents a novel receiver architecture for full-duplex multi-level PAM systems. The receiver employs an Analog-to-Digital Converter (ADC) that has a sample rate flexibly specified as (N_s+1)/N_s baud rate where N_s is an integer equal or greater than 1. A fractional-spaced echo canceller is used to cancel the echo at the ADC output. The use of a fractional sampling rate higher than the baud rate also enables the timing recovery function be implemented in the digital domain and hence eliminates the need of using the complex analog phase selection circuit. The receiver is also capable of fast, blind start-up by use of a decision feedback equalizer with unity main tap and a soft level slicer. The timing phase can be optimally located using a derivative channel estimator. Once the “eye-open” condition is achieved, the channel equalization is switched to the use of linear equalizer coupled with an error feedback equalizer to alleviate the error propagation problem associated with the decision feedback equalizer.

The invention provides a method for controlling a servo system of an active disturbance rejection control technology, and aims to provide a method which has a simple algorithm, wide parameter adaptability and small servo system tracking dynamic error, and keeps the disturbance rejection capability of an automatic disturbance rejection controller (ADRC) control system. The method is realized through the following technical scheme that: firstly, a command differentiator ComD is substituted for a tracking differentiator TD which is arranged for a transition process of a standard active disturbance rejection control algorithm, and extracts a new location command value w1, a new speed command value w2 and a new acceleration command value w3; an extended state observer ESO in the standard active disturbance rejection control algorithm is continuously adopted, and calculates a system location observation value z1, a speed observation value z2 and an acceleration observation value z3; and w1 and z1 form a location error e1, w2 and z2 form a speed error e2, e1 and e2 are sent to a nonlinear state error feedback regulator (NLSEF), w3 and the output u0 of the NLSEF are added, w3 is taken as a feedback value, so the servo system of the improved active disturbance rejection control technology is formed.

The invention discloses a diagnostic method for gas path faults of an aero-engine based on the sliding mode theory. The method comprises following steps: intelligently correcting a non-linear part-stage model of the aero-engine based on an artificial bee colony algorithm; obtaining a self-adaptive liner model of the aero-engine based on error feedback sliding mode control; designing an expansion interface estimation sliding mode observer, and achieving fault diagnosis, separation and reconstruction of an engine sensor; achieving fault diagnoses of gas path faults of the engine. The diagnostic method for gas path faults of the aero-engine based on the sliding mode theory has following beneficial effects: as for the gas path faults of aero-engine, a correction method for a high-precision part-stage mode for the engine is put forward with the purpose of improving reliability and safety of a system; a new way of thinking for a self-adaptive linear model for the engine is put forward for providing a new strategy of gas path faults of the aero-engine; difficulties of gas path faults of the aero-engine and sensor faults are solved so that an effective and highly-reliable fault diagnoses method is put forward.

The invention discloses a real-time sensorless brushless motor phase change phase correction method based on the voltage of neutral points. By the adoption of the real-time sensorless brushless motor phase change phase correction method, the phase change position errors of a permanent-magnet brushless motor without a position sensor can be effectively reduced, and the optimum-position phase change is achieved. According to the real-time sensorless brushless motor phase change phase correction method, the voltage differences of neutral points within the 30-degree range on the front side and the 30-degree range on the rear side of a phase change point are collected and calculated so that the current phase error of the phase change can be determined, the voltage differences are used as phase change error feedback quantity, and real-time correction of the permanent-magnet brushless motor is achieved. Experiment results show that no matter whether the load is light or heavy, the phase change phase correction of the permanent-magnet brushless motor without the position sensor can be achieved.

The invention discloses an in-process evaluation based complex spatial surface error feedback compensating method. The method comprises the following steps of processing a complex surface cutting force module through a ball-end cutter, performing dynamic compensation for a target cutter location point for workpiece pre-processing; performing in-process detection for the pre-processed workpiece to obtain geometrical information of an actual contour; evaluating error for the pre-processed workpiece through a contour degree error evaluation model; when the contour error is greater than tolerance, determining a compensation point position U1 corresponding to each contact point; guiding the compensation point position corresponding to each contact point to three-dimensional CAD (Computer-Aided Design) to obtain a compensating process contour to generate a compensating processing tool track; and performing static compensation and processing for the pre-processed workpiece and finishing the flow. Under the premise of ensuring the processing precision of part surface, the processing precision of the part is detected in process without investing fund to purchase more detection devices, so that the conveying and loading time of workpieces is shortened.

A method and modem receiver for receiving serial data from a transmission link, for recovering data from the received data, and for synchronizing the receiver timing to that of the transmitter are disclosed. A receiver equalizer includes a filter and quantizer in the forward path and a feedback circuit connecting the quantizer output to the filter input. A measuring circuit is used to initialize the feedback circuit. The receiver filter, provided as a QMF wavelet filter bank, is implemented in one embodiment with a form of polyphase filtering followed by four M/2-point FFTs. The quantizer recovers data symbols and provides a quantization error feedback signal. The measuring circuit provides an approximation of phase and amplitude of isolated wavelets.