40 results about "Reference tracking" patented technology

A method includes obtaining a reference tracking performance ratio and a disturbance rejection performance ratio associated with a model predictive control (MPC) controller. The method also includes filtering an output target signal for the controller using a first filter based on the reference tracking performance ratio. The method further includes filtering a feedback signal for the controller using a second filter based on the disturbance rejection performance ratio. The filters can provide two degrees of freedom for tuning reference tracking and disturbance rejection operations of the controller. The reference tracking operation of the controller and the disturbance rejection operation of the controller can be independently tunable. The reference tracking performance ratio can control how aggressively the controller responds to a change in the output target signal. The disturbance rejection performance ratio can control how aggressively the controller responds to a disturbance in the feedback signal.

A system and method for spatially stretching visual interactive computer-based renderings of hierarchical 3D/4D object models is disclosed. Hierarchical 3D/4D object models are transformed into a stretchable structure. Utilizing user interface controls, a user manipulates and visually stretches the 3D/4D object model hierarchy to expose 3D/4D object model components for an unobstructed view. Real-time geo-referenced data feeds are processed to interactively update specific sensor objects contained as components of the hierarchical 3D/4D object models. Real-time geo-referenced tracking data feeds are also processed to dynamically include new visual components of the 3D/4D object model hierarchy at the proper location, representative of the locations of mobile tracking devices within the 3D/4D object model hierarchy.

A method, computer program product, and computer system for determining, by a computing device, that an object of a plurality of objects is an orphan. It may be determined that the object is older than a threshold age. A capacity occupied by the object may be reclaimed based upon, at least in part, determining that the object is an orphan and determining that the object is older than the threshold age.

The invention discloses a three-axis sun-oriented control method of a satellite for a guaranteeing satellite-earth link. The three-axis sun-oriented control method comprises the following steps: solving a projection of a sun vector under a satellite orbit coordinate system according to the sun vector calculated according to a satellite orbit; establishing a sun-oriented reference coordinate system according to the satellite orbit and the definition of the satellite polarity, and calculating an attitude quaternion of the sun-oriented reference coordinate system relative to the satellite orbit coordinate system; calculating an error quaternion between an attitude quaternion of a star relative to the satellite orbit coordinate system and the attitude quaternion of the sun-oriented reference coordinate system relative to the satellite orbit coordinate system; carrying out attitude reference tracking according to a symbol of the error quaternion; and when continuously meeting that the error quaternion is smaller than a preset threshold value, establishing a star sensor sun-oriented sign, carrying out three-axis stabilization sun-oriented control by virtue of a star sensor, and otherwise, continuing to carry out two-axis sun-oriented control based on sun sensor. By virtue of the three-axis sun-oriented control method, the smoothness of the satellite-earth link after the sun orientation of a sailboard can be guaranteed, and a near-optimal maneuvering path is guaranteed when a sun-oriented maneuvering manner is changed into a ground-oriented maneuvering manner.

The invention discloses a target real-time tracking method and device, a computer device and a storage medium. The target real-time tracking method comprises the following steps: acquiring original video data; selecting a reference image from the original video data and detecting an object to obtain at least one reference tracking object and a corresponding reference object feature vector; performing target detection on the current image to obtain at least one current tracking target and a corresponding current target feature vector; determining feature similarity of each benchmark tracking target based on the benchmark target feature vector and the current target feature vector; if the feature similarity is less than the preset similarity, determining the reference tracking target corresponding to the feature similarity to be a missing tracking target in the current image; and if the feature similarity is less than the preset similarity; if the reference tracking target is lost in theN consecutive frames after the current image, releasing the reference tracking target. The real-time target tracking method can judge and release the lost target, and improve the accuracy and efficiency of target tracking.

An object specifying device mounted in a controlled vehicle has a unit for tracking objects, existing in a monitoring area set along a running direction of the controlled vehicle, to detect the objects as forward objects, a unit for specifying one forward object running in the area as a forward vehicle, a unit for specifying each of other forward objects as a candidate for a control-based object when the forward object is placed in an inter-vehicle area between the controlled and forward vehicles, and a unit for specifying each candidate, tracked for a tracking period equal to or longer than a reference tracking period, as a control-based object and specifies each candidate, tracked for a tracking period shorter than the reference tracking period, as a non-control-based object. The controlled vehicle is controlled according to a movement of the control-based objects, regardless of a movement of the non-control-based objects.

The invention provides a wind magnetic suspension cabin suspension control method which aims at a nolinear wind cabin suspension system with strong interference and heavy suspended matter and can reasonably divide a control task from interference suppression. The method includes the steps that cabin suspension is divided into two parts including suspension mechanical dynamics and converter currenttracking, the suspension mechanical dynamics completes suspension air gap control and sets converter suspension current reference, and the converter current tracking completes suspension current reference tracking; the suspension mechanical dynamics adopts a suspension steady-state controller and an interference compensator to complete suspension current reference setting in a coordinated manner;and the converter current tracking adopts a current tracking steady-state controller and a self-adaption counter electromotive force compensator to cope with influences of counter electromotive forcechanges caused by suspension air gap fluctuation and converter parameter changes caused by suspension temperature rise on current tracking in a coordinated manner. The wind magnetic suspension cabinsuspension control method improves the steady state performance and the interference suppression capability of the cabin suspension system, and lays a foundation for wind alignment of wind turbine cabin yaw.

Systems and methods are provided for calibrating electromagnetic position tracking systems commonly used in virtual reality systems by compensating for steady state magnetic field distortions that can occur within a tracking volume and distort magnetic sensor readings. The calibration system includes a calibration device that holds magnetic sensor(s) in a fixed position relative to a reference position sensor object provided on the calibration device. The calibration data collection process includes positioning the calibration device at multiple locations within a tracking volume and measuring magnetic position readings using a magnetic tracking system and a corresponding reference position using the reference position tracking system. The calibration data is then algorithmically processed using a data processor to generate a magnetic distortion correction function for adjusting the magnetic tracking system measurements based on a known position of said sensors, which is determined from the measured position of the reference tracking object.

According to one embodiment, there is provided an optical disk apparatus including: a first determination unit configured to set a reference tracking offset and determine a reference recording power by an optimum power control processing; a tracing unit configured to trace a predetermined area in an optical disk by changing the tracking offset through use of an erase power calculated from the reference recording power; an acquisition unit configured to acquire an address information acquisition rate serving as a rate for reading address information, when data are traced in the predetermined area of the optical disk by changing the tracking offset within a predetermined range by the tracing unit; a second determination unit configured to determine, from the address read rate, a recording-operation tracking offset used during processing for recording the data into the optical disk; and an adjustment unit configured to adjust the recording-operation tracking offset.

The invention discloses a sub-pixel-level target tracking method based on feature matching. The sub-pixel-level target tracking method comprises the following steps: selecting a tracking point of a first frame of image from continuously transmitted images as a reference tracking point; respectively processing the first frame of image and the Nth frame of image to obtain a feature vector of the first frame of image and a feature vector of the Nth frame of image, N being a natural number greater than 1; matching the feature vectors of the first frame of image and the Nth frame of image to obtaina feature point pair; and estimating the feature point pair to obtain a conversion matrix, carrying out point multiplication operation on the conversion matrix and the reference tracking point to obtain a new tracking point, and finishing updating of the tracking point. According to the sub-pixel-level target tracking method based on feature matching provided by the invention, high-precision tracking can be carried out on one point in a target, and robustness is achieved when obvious representation change occurs in an image tracking point region; meanwhile, the method is simple in calculationand high in parallelism, facilitates acceleration calculation, and can be widely applied to a high-speed high-precision real-time tracking photoelectric countermeasure system.

The invention provides a photovoltaic module tracking control method and a related device, and the method comprises the steps: determining a to-be-adjusted tracking axis and a reference tracking axis in which a photovoltaic module string is not shielded; when the reference power generation performance parameter of the reference tracking shaft and the actual power generation performance parameter corresponding to the tracking shaft to be adjusted meet the preset angle adjustment rule, indicating that the photovoltaic module string on the tracking shaft to be adjusted is shielded, and at the moment, calculating the loss value of the actual power generation performance parameter relative to the reference power generation performance parameter; determining the correction angle corresponding to the loss value and correcting the angle of the to-be-adjusted tracking shaft according to the correction angle, so that the photovoltaic module string arranged on the to-be-adjusted tracking shaft is adjusted to a non-shielded state, the light utilization rate of the photovoltaic module string is improved, and the generating capacity of the photovoltaic module string is improved.

The present invention discloses a method and apparatus to provide, effectively and robustly, a phase reference in phase-domain for digital phase-modulated signals. Not only the first-order but also higher order PLLs are delineated for robust and fast tracking of frequency errors and time-varying frequency errors between the transmitter and the receiver. This invention can be applied to any phase-modulated signal such as PSK, DPSK, [pi]/4-DPSK, and CPM. The decoders with this invention can achieve close to the performance of coherent detection.

A design method for the current controller of a grid connected inverter is discussed in this disclosure. The repetitive control strategy is used, in tandem with a mu-synthesis based current controller, to attain robust sinusoidal reference tracking and harmonic rejection. Uncertainty in the input DC voltage (±50%) is considered and expressed in static form. Mu-synthesis based control is chosen to attain robust reference tracking in the presence of plant uncertainties. The repetitive control strategy is selected since it can reject a large number of harmonics simultaneously, while providing a clean sinusoidal current waveform to the grid, even in the presence of grid load and/or voltage distortions. The repetitive control strategy is implemented via the internal model principle. By applying mu-synthesis principles, a feedback controller that simultaneously achieves robust stability and robust tracking performance is obtained.

The control device of a movement simulator, between its input formed of a control signal and its output formed of a measured magnitude among its speed, its position and its acceleration, by a transfer function B(z⁻¹)/A(z⁻¹) includes a corrector synthesized from the modelling of the movement simulator and equivalent to a RST controller. The controller includes a reference input, a retro-action input whereon is applied the measured magnitude and an output producing the control signal. The transfer function between the reference input of the controller and the measured magnitude is H(z⁻¹)/W(z⁻¹). The device has a reference filter whose input is a sinusoidal reference signal c(t) at a frequency wc and applying at output a filtered reference signal on the reference input of the controller. The reference filter has a transfer function Rr(z⁻¹)/Fr(z⁻¹), whose denominator and numerator are adapted to ensure, for the frequency wc, effective tracking by the movement simulator of the sinusoidal reference.

The invention provides an electro-hydraulic servo controller and a construction method thereof, an electro-hydraulic servo system and an operation machine. The electro-hydraulic servo controller comprises an integration unit and an anti-saturation unit. Through the integration unit, the steady-state error of the electro-hydraulic servo controller can be eliminated, reference tracking can be ensured, excitation oscillation and possible load step can be actively inhibited, and the phenomenon that undamped oscillation cannot be eliminated by the integration unit can be avoided. Through the anti-saturation unit, anti-saturation protection of the integration unit can be realized. Through the electro-hydraulic servo controller, the control on a hydraulic actuating mechanism can be more accurately realized, and the performance of the hydraulic actuating mechanism can be greatly improved.

The invention provides a vehicle tracking method and device. The method comprises that when target detection information fed back by a vehicle-mounted sensor is received, a target vehicle is selected,and a target tracking model of the target vehicle in a self vehicle coordinate system is generated; a target effective association point of the target tracking model is calculated; and an associationscore between the target vehicle and each reference vehicle in a present target tracking list is calculated to update a reference tracking model or establish a new reference vehicle. On the basis ofthe method of the invention, the target models of different vehicle-mounted sensors are associated and tracked according to the effective association point, incorrect content can be eliminated from the detection information fed back by the vehicle-mounted sensors, and the subsequent associating efficiency and accuracy are improved.

The invention relates to a target tracking method and device, an event detection method and device, electronic equipment and a storage medium. The target tracking method comprises the steps: carrying out the face recognition of an object in a video stream, determining a to-be-tracked object in the video stream, and determining a to-be-tracked identifier of the to-be-tracked object; determining whether a to-be-tracked identifier is included in a target library, the target library including a tracking identifier of a reference tracking object and face feature information of the reference tracking object; under the condition that the to-be-tracked identifier is not included in the target library, performing feature matching based on the extracted face feature information of the to-be-tracked object and the face feature information of the reference tracking object; and under the condition that the face feature information of the to-be-tracked object is successfully matched with the face feature information of the reference tracking object, performing association tracking on the to-be-tracked object and the reference tracking object with the successfully matched features, wherein the association tracking is used for associating the tracking data of the to-be-tracked object with the tracking data of the reference tracking object with the successfully matched features.