136results about How to "Improve tracking speed" patented technology

The invention discloses a method for tracing the track of a wheeled mobile robot based on a quantum-behaved particle swarm algorithm. The method sets a coordinate system within a motion range first, establishes a kinematic model of the wheeled robot, utilizes an inversion design method to decompose the kinematic model, obtains an error propagation equation of a reference pose and an actual pose through the track generated by path planning, takes the equation as a target function, utilizes the quantum-behaved particle swarm optimization algorithm to obtain parameters of a controller with quick speed and strong global solving capacity, designs the controller through the group of parameters, and further guarantees that the robot can be stably and quickly converged on the target track, namely the target function value is close to or less than an allowable value within a limited time period. The method solves the problems of high nonlinearity and non-integrity of track tracing of the wheeled mobile robot, and can quickly realize track tacing of the wheeled mobile robot and improve the tracing control effect of the mobile robot.

The invention discloses a movement capturing method based on multiple binocular stereo vision. A movement video collecting device is constructed, and human movement video sequences from different orientations are collected by the movement video collecting device. Multiocular movement video sequences shot by a plurality of cameras are calibrated. Marked points matching and tracking of each binocular tracker is finished. Data fusion of three-dimensional tracking result of multiple binocular trackers is completed. The three-dimensional movement information of the marked points acquired by a multiocular fusion device is fed back to the binocular tracker to consummate binocular tracking. On the basis of binocular three-dimensional tracking realized by binocular vision, the invention fuses multiple groups of binocular three-dimensional movement data, resolves parameter acquiring problem of three-dimensional position, tracking, track fusion and the like for a plurality of marked points, increases number of traceable market points and enables the tracking effect to be comparable with three-dimensional movement acquiring device employing multi-infrared cameras for collecting.

The invention provides a fuzzy sliding mode trajectory tracking control method for an SCARA robot with modified sliding mode surface and reaching law. The method has the advantages that no precision dynamical model is required, and robustness is high; a fast terminal sliding mode surface which is modified is adopted, so that convergence rate of a system is increased, and singularity of the traditional terminal sliding mode surface is eliminated; the fast reaching law is adopted, the exponential approach law features fast reaching when leaving the sliding mode surface, power reaching law features smooth reaching when reaching the sliding mode surface, and tracking speed is increased, and meanwhile trajectory tracking precision is guaranteed; a sign function is replaced with a hyperbolic tangent function, and accordingly, high frequency chattering of the system is eliminated effectively; exponential term coefficient of the reaching law is corrected with a fuzzy adaptive controller, and the problem of moment shock caused by large system initial error is improved.

The present invention relates to Voltage balancing control method for modular multilevel converter is characterized that, it includes some steps as follows:

1) Determine the leg current direction is positive or negative;

2) Find out the highest sub module on output state whose capacitor voltage amplitude is the maximum, and find out that on bypass state whose capacitor voltage amplitude is the minimum;

3) Determine whether the sub module inputs or bypass operation; this method avoided switching arbitrariness of the sub module, and decreased the switching frequency of the sub module. The capacitor voltage balancing control of the sub module proposed by the method is more suitable to be applied in the field of high voltage and large capacity converter that has large numbers of sub modules.

The invention provides a multi-angle multi-target fast human face tracking method used in a video sequence, which belongs to the technical field of video processing. Through multi-angle human face fast detection and color histogram establishment in a human face region, a color probability graph of an image to be detected is calculated, Camshift arithmetic iterating results are used for updating the human face region position and simultaneously upgrading a human face moving model established by a Kalman filter, and at the same time, the human face prediction is carried out when a target is shielded: when the human face is shielded, the human region position is predicted by the Kalman filter, and then, the human face moving model is updated. The invention can fast eliminate the non-human face region so that the real-time multi-angle multi human face target tacking becomes possible. At the same time, through the introduction of the Kalman filter, the invention can use the prediction results of the Kalman filter for updating the position of the shielded target when the target shielding occurs in the video sequence, and the tracking difficulty caused by shielding can be perfectly overcome.

A narrowband signal detector has an adaptable filter and controller for controlling the centre frequency and the bandwidth of the filter, to track the narrowband signal. Better control of the filter can be achieved by basing the filter control on a comparison of output and input to the filter. The comparison gives a more direct measure of how well the filter is tracking the narrowband signal. In the case of a notch filter, if there is poor tracking. The control should be biased rapidly towards improved tracking speed. Otherwise, for good tracking, the control should be biased towards accuracy of tracking. This enables speed and accuracy of detection requirements to be met with less computational load. Applications include telecommunications signalling or data tone detection. Multiple narrowband signals can be detected by a cascade of filters.

A first imager has a relatively high resolution and a relatively narrow first field-of-view. Information about objects in an environment is detected or captured, and used to steer the first field-of-view of the first imager. The sensor(s) may take the form of a second imager with a relatively lower resolution and relatively wider second field-of-view. Alternatively, other types of sensors, for instance presence/absence sensors may be employed. The first field-of-view may be directed toward an object that satisfies one or more conditions, for instance matching a particular SKU. The first field-of-view may track a moving object, for instance via a tracking mirror and actuator. This approach may be employed in retail locations, for example in grocery or convenience stores, for instance to reduce various forms of theft or in industrial environments.

An End-Point Prediction scheme is described for voltage-mode buck regulators to generate adaptive output voltage to integrated-circuit systems. Internal nodal voltages of the regulator controller are predicted and set automatically by the proposed algorithms and circuits. The settling time of the regulator can therefore be significantly reduced for faster dynamic responses, even with dominant-pole compensation.

The embodiment of the invention relates to a power-supply apparatus and control method, a power amplifying device. The device includes a includes linear branch and a first switch power supply group, the first switch power supply group includes a first current detector and at least two switch power supply branches, the switch power supply branch includes a hysteresis controller and a switch power supply drive and power circuit, the input end of the first electrical current detector is connected with the output end of the linear power supply branch, the input end of the hysteresis controller is connected with the output end of the first electrical current detector, the input end of the switch power supply drive and power circuit is connected with the output end of the hysteresis controller, the output end thereof is in parallel connection with the output end of the linear power supply branch. The embodiment of the invention can improve the band width and the tracking accuracy of the switch power supply, further improve the integral efficiency of the ET power amplifier.

The present invention provides a maximum power point tracking method and device and a photovoltaic power generation system. The maximum power point tracking method comprises: sampling present voltage and present current of a photovoltaic array; obtaining present power based on the present voltage and the present current; using difference between the present power and power for previous sampling time as present perturbation power, and based on ratio of the present perturbation power to perturbation power for previous sampling time, obtaining gradient perturbation voltage step ratio; obtaining perturbation voltage step based on the gradient perturbation voltage step ratio and voltage difference between the present voltage and the voltage for previous sampling time; and controlling output voltage based on the perturbation voltage step.

A bone strength diagnostic device comprises oscillators, a determination index calculator, a tracking start point setting component, and a tracking execution component. A plurality of the oscillators are disposed in a line to acquire echo signals of a transmitted ultrasound beam. The determination index calculator calculates a determination index expressing a probability that the echo signal is a reflected wave from the surface of a cortical bone. The tracking start point setting component sets a tracking start point at a signal waveform timing corresponding to the echo signal for which the determination index satisfies a specific condition and that is received by one of the plurality of oscillators. The tracking execution component successively sets tracking points for the echo signals acquired from other oscillators using the tracking start point as an origin.

The invention relates to a passive integral sliding mode control method for a double-fed wind power system. The method comprises the following steps: (a) creating a Euler-Lagrange mathematical model of a double-fed wind power generator and strictly and passively analyzing the model; (b) designing a current feedback passive controller by a damp injecting method on the basis of the step (a), starting with an energy balance relationship; (c) giving an improved integral sliding mode control method, designing an integral sliding mode surface to completely eliminate the arrival phase of a general sliding mode, and taking the process as an outer ring rotating speed control strategy. The method has the advantages that the system is guaranteed to be globally stable, the control structure is simplified, and the asymptotic tracking of electromagnetic torque and magnetic flux linkage is realized; the arrival phase of the general sliding mode is eliminated, the tracking speed of the rotating speed of a double-fed motor is increased, and the robustness of the rotating speed of the double-fed motor is improved; the wind power system can be ensured to safely and stably run and a valuable reference scheme is provided for improving the working efficiency of the wind power system.

The invention discloses an anti-blocking target tracking method based on partitioning. In combination of the quick tracking speed and the good tracking effects of a kernel correlation filter (KCF) tracking algorithm, the real-time performance of a partitioning method is ensured. The method uses a high-confidence model updating strategy, a model drift problem of the KCF in the case of blocking can be solved, the tracking speed and the tracking precision are quickened, and besides, when the partitioning method is used, after a part is blocked during the target tracking process, the position information and the reliability of the unblocked part are used reasonably, the position information after the target is blocked is determined accurately, and the robustness of tracking towards blocking is thus improved. As the method can meet the real-time performance, the method can be applied to a real scene.

A system for extracting one or more acoustic signals from a plurality of source signals emitted by a plurality of sources, respectively, in an environment, the system comprising an array of microphone receivers for receiving the one or more acoustic signals from the environment and transmitting the signal to a signal processor, wherein the signal processor is arranged to estimate the plurality of source signals using the data received by array of receivers, the signal processor is further arranged to perform an operation on the data received by the array of receivers with the estimated source signals to provide an estimate of the impulse response of the environment, wherein the data received by the array of receivers is input to the estimate of the impulse response of the environment to provide an output comprising a plurality of channels, wherein one or more of the channels correspond to the one or more acoustic signals from one of the plurality of sources, respectively.

A multi-leaf collimator for a radiotherapy apparatus comprises a plurality of elongate leaves mounted in a carriage, the carriage being mounted on a substrate, wherein the leaves are independently moveable relative to the carriage in a longitudinal direction, and the carriage is moveable in that direction relative to the substrate, and a control apparatus arranged to receive a signal representing leaf positions relative to the substrate and being arranged to control the leaf positions relative to the carriage and the carriage positions relative to the substrate so as to achieve those leaf positions relative to the substrate. By allowing the carriage to be driven concurrently with the leaves, the speed of movement of the carriage can be added to that of the leaves. In this way, where leaves are required to make a long traverse they can do so more quickly. Most MLCs have a means for sensing the current positions of the leaves relative to the substrate, such as an optical or mechanical positional feedback system. The control apparatus can therefore compare the current leaf positions to the signalled leaf positions, and move the leaves and the carriage accordingly. Each leaf can be moved according to a difference between the current leaf position and the signalled leaf position, and the carriage can be moved according to an average difference between the current leaf positions and the signalled leaf positions. A corresponding method is also disclosed.

The invention discloses a system and a method for controlling a doubly-fed wind power generation grid-side converter. The system comprises a model predictive control module and a space vector modulation module. The model predictive control module controls a voltage transfer function according to dq-axis current and the dq axis of the grid-side converter, acquires a first-order difference equation of a PWM-VSR (pulse width modulation voltage source rectifier) after discretization to serve as a predictive control model and calculates control voltage of the grid-side converter in a real-time online manner by feedback correction and rolling optimization. The space vector modulation module generates a switching signal for operation of the grid-side converter according to the control voltage and controls the grid-side converter in grid-connected operation. By the aid of the system and the method, the influence of lagging of the control voltage caused by sampling delay of voltage and current of the grid-side converter can be eliminated, grid-side dq-axis current is completely decoupled, the negative influence of grid-side inductance parameters on stability and dynamic response of the system can be overcome, three-phase input current effectively tracks input power grid voltage phase, and the grid-side converter is ensured to be operated in a high power factor state.

The invention provides a 16 quadrature amplitude modulation (QAM) demodulation synchronization method. The method comprises a first step of adding a power detection technology on a traditional costas loop of quadrature phase shift keying (QPSK) so as to finish carrier recovery; a second step of performing matched filtering on each same-phase orthogonal component signal, so as to reduce noise effect and prepare for bit synchronization; a third step of performing bit timing recovery on same-phase orthogonal signals through an "early-late gate"; a fourth step of setting a threshold, and performing sampling judgment and 4-2 level conversion on each of two paths of signal to obtain parallel signals; and a fifth step of performing differential decoding and parallel-serial conversion on the parallel signals, then recovering and obtaining original signals. According to the introduced novel carrier synchronization technology, the carrier recovery is finished by using a phase-locked loop; on the basis of the traditional costas loop, the power detection technology is added, so that the linear output of a phase discriminator is guaranteed, the tracking precision and speed are improved, and the novel carrier synchronization technology passes field programmable gate array (FPGA) hardware verification.

The invention discloses a guidance law design method for unmanned aerial vehicle path tracking control. The method includes the following steps that S1, the flying speed of an unmanned aerial vehicleis V, projection is conducted on a preset track from the initial position A of the unmanned aerial vehicle, a projection point is marked as O, and the distance between the flying path of the unmannedaerial vehicle and the preset track is marked as d; S2, a circle with the radius being r is obtained with the projection point as the circle center, the intersection point of the circle and the presettrack in front of the unmanned aerial vehicle speed direction is marked as B, the length of AB is marked as L1*, and a L1* guidance law is designed with the point B as a reference point; S3, a reference circle O1* with the radius being R* is selected, and an unmanned aerial vehicle lateral acceleration instruction as* is calculated by using centripetal acceleration and motion geometrical relationship. The method has the advantage that the problem that the tracking speed is too low in tracking control in the prior art can be solved.