423 results about "Angular error" patented technology

The invention discloses a calibration method of correlation between a single line laser radar and a CCD (Charge Coupled Device) camera, which is based on the condition that the CCD camera can carry out weak imaging on an infrared light source used by the single line laser radar. The calibration method comprises the steps of: firstly, extracting a virtual control point in a scanning plane under the assistance of a cubic calibration key; and then filtering visible light by using an infrared filter to image infrared light only, carrying out enhancement, binarization treatment and Hough transformation on an infrared image with scanning line information, and extracting two laser scanning lines, wherein the intersection point of the two scanning lines is the image coordinate of the virtual control point in the image. After acquiring multiple groups of corresponding points through the steps, a correlation parameter between the laser radar and the camera can be solved by adopting an optimization method for minimizing a reprojection error. Because the invention acquires the information of the corresponding points directly, the calibration process becomes simpler and the precision is greatly improved with a calibrated angle error smaller than 0.3 degree and a position error smaller than 0.5cm.

A control apparatus for a brushless DC motor that rotatably drives the brushless DC motor including a rotor having a permanent magnet, and a stator having stator windings of a plurality of phases that generate a rotating magnetic field for rotating the rotor, by a current passage switching device constituted by a plurality of switching elements and performing successive commutation of current to the stator windings. The control apparatus includes: an angular error calculation device for calculating a sine value and a cosine value of an angular difference between an estimated rotation angle with respect to the rotation angle of the rotor and an actual rotation angle, based on a line voltage that is a difference between phase voltages of the plurality of phases on an input side of the stator winding and phase currents of the plurality of phases; and an observer for calculating the rotation angle of the rotor based on the sine value and the cosine value of the angular difference.

The invention relates to a multiturn absolute rotary encoder based on a rotary transformer, which is characterized in that: a sensor is displaced by taking the rotary transformer as a shaft angle; a shaft angle decoding circuit can be formed by adopting DSP as a core processor; a sine wave which can be controlled by frequency and phase in the method that the circuit is synthesized by direct digital frequency for the numerical control of an oscillator; and the sine wave is directly taken as an excitation rotary transformer signal via a power amplifier and a filter circuit; the rotary transformer signal is transferred to A/D converter after being run through a matching circuit of electronic transformer; after sampling, digital filtering and digital signal processing, the sine and cosine value for the actual angle of two channels is generated; the angle error change is tracked dynamically by the PI algorithm; the mechanical displacement of the rotating object is converted into digital shaft angle position and speed. The multiturn absolute rotary encoder based on a rotary transformer has the advantages of high tracking speed, high conversion accuracy, high reliability, simple structure, sensitive movement, low environmental condition, strong anti-interference capability, high measuring accuracy and speed voltage output.

The invention relates to a yaw control method for a large-sized wind powered generator unit. A current yaw angle reference value alpha reference is obtained according to a current wind direction, a current yaw angle practical value alpha practice is obtained by a encoder or a tachometer, a yaw angular error delta alpha is obtained by subtracting the yaw angle practical value alpha practice by the current yaw angle reference value alpha reference, and a corresponding yaw mechanism control rule is calculated by integrating the yaw angular error delta alpha and the variation tendency thereof by a fuzzy controller. Furthermore, an obtained electrical signal of the yaw mechanism control rule is sent to a yaw actuating mechanism to control a propeller pitch angle, and the yaw angle of the wind powered generator unit traces the yaw angle reference value alpha reference to enable the yaw angle practical value alpha practice and the yaw angle reference value alpha reference of the wind powered generator unit to be kept consistent. The invention obviously enhances the total precision, is favorable to increasing the year total generated energy of the wind powered generator unit, has high adaptability for complex and extreme cases, greatly enhances the operating effectiveness, furthest prolongs the mechanical life of the yaw actuating mechanism, and also has low remodel difficulty and low cost.

A resolver apparatus having a high detection precision detecting angle signals from signals detected at a resolver (7) and detecting a velocity signal from the detected angle signals. Utilizing the fact that an error waveform of a resolver is comprised of predetermined n-th order components inherent to the resolver and has reproducibility, an angle error estimator (13) applies a frequency transform, for example, a Fourier transform, to high frequency components of velocity signal including error generated from detected angle signals including error to calculate a magnitude of error for each of a plurality of divided components and combining the calculated errors to reproduce the detected error and generate an error waveform signal. An angle signal correction circuit (14) uses this error waveform signal to correct an angle signal including error detected at the resolver.

In an image drawing apparatus and an image drawing method for multiple-overlay image drawing, uneven density and resolution caused by an error of installation angle of an image drawing head and by pattern distortion can be reduced. A rectangular two-dimensional pixel array is installed in each of exposure heads in an exposure apparatus (image drawing apparatus) so as to make a predetermined angle with the scanning direction, facing an exposure surface. Slits and photo detectors detect in the exposure surface an actual installation angle of a representative light-spot column near the center of the pixel array. Active pixels in the pixel array are selected so as to realize multiple-overlay exposure ideally by causing overexposure and underexposure to be minimal in an area near the representative light-spot column, based on the measured angle. Exposure is carried out by causing only the active pixels to operate.

The present invention belongs to the field of precise instrument manufacture and measurement technology, and is especially self-separation method and device for spatial error of super-precise revolution reference. The method of Z-direction section-by-section separation of super-precise revolution reference spatial motion error can meet the requirement of high precision cylindricity instrument to reduce spatial revolution error. The self-separation device for spatial error of super-precise revolution reference is developed by means of integrating roundness error separating system and cylindricity instrument revolution main shaft system. The bench revolving single-transposition small-angle error separation method is adopted in realizing the section-by-section separation of spatial revolution motion error of cylindricity instrument revolution main shaft, so as to reach the aim of reducing the effect of the spatial revolution motion error on measurement result.

To correct an angle error, acceleration data is received corresponding to a tracked object in a reference frame of the tracked object. Positional data of the tracked object is received from a positional sensor, and positional sensor acceleration data is computed from the received positional data. The acceleration data is transformed into a positional sensor reference frame using a rotation estimate. An amount of error between the transformed acceleration data and the positional sensor acceleration data is determined. The rotation estimate is updated responsive to the determined amount of error.

A navigation system includes: an angular velocity sensor 1 for detecting a change in an advancement direction of a vehicle; a vehicle azimuth calculation unit 13 for calculating a vehicle azimuth on the basis of angular velocity sensor information obtained from the angular velocity sensor; an on-board camera 2 for shooting a periphery of the vehicle; an image recognition unit 19 for recognizing an image obtained from the on-board camera; and an offset voltage correction unit 21 for performing a drift correction on the angular velocity sensor in accordance with an angle error between the vehicle azimuth calculated by the vehicle azimuth calculation unit and a vehicle azimuth determined from a white line on a road recognized by the image recognition unit.

The invention discloses a self-adaptive optical fiber coupler or collimator control system capable of bilaterally receiving and transmitting laser beams. The self-adaptive optical fiber coupler or collimator control system comprises a coupling or collimating lens, a connecting sleeve, an optical fiber end face positioner, a first optical fiber, a three-port optical fiber circulator, a second optical fiber, a third optical fiber, a laser, a photoelectric detector, a control platform and a high-voltage amplifier, wherein the optical fiber end face positioner comprises a flexible crossed beam, a bimorph driver, a damping material, a boss and a fixed seat. Due to the adoption of the self-adaptive optical fiber coupler or collimator control system, the light beam arriving angle errors caused by factors such as atmosphere turbulence, mechanical vibration, thermal distortion and the like can be corrected adaptively; and meanwhile, according to the reversibility principle of a light path, the transmitting angle correction of emitted collimating light beams is also realized. The self-adaptive optical fiber coupler or collimator control system has an important application prospect in the field of optical fiber-based laser space application, such as free space laser communication, laser precise positioning and laser radar.

Disclosed is an automatic measuring compensation and correction method for five-axis machine tool structure errors. A five-axis correction block is mounted on a machine tool worktable and comprises adatum square table and a datum circular ring. The side surface and the top surface of the datum square table are parallel to the coordinate axis of a machine tool. A five-axis error model is established, and the error components delta<x>, delta<y> and delta<z> in the x, y and z directions and the main shaft axial error L<spd> are obtained; a machine tool numerical control system is used for starting a five-axis structural error automatic measuring cycle macroprogram, the axis angle error of a rotating shaft of the machine tool and the position error of the rotating shaft axis and the main shaft axis are measured; the axial error of a main shaft is measured; and the measured and obtained axis structural error of the main shaft and the main shaft axis error are substituted into the established five-axis error model, and compensated to all movement coordinate axes in the interpolation cycle of the machine tool numerical control system. The invention further discloses an automatic measuring and compensating correction device for the five-axis machine tool structure errors, automatic measuring and compensating of the five-axis machine tool structure errors are achieved.

The invention provides a self tracking method for a spacecraft dynamic target by a spherical phased array antenna, which aims at providing a simple and reliable tracking method with little hardware resource consumption. The technical scheme comprises steps: radio frequency signals received by four array antenna links form beam forming signals through a DBF weighting module, a difference beam forming module transmits sum/difference beam signals to a rear-end baseband angle error demodulation module for being processed, azimuth error voltage and pitching error voltage are solved, the azimuth error voltage and the pitching error voltage are transmitted to a waveform control computer for being processed, the waveform control computer uses waveform control software to estimate a target incomingwave direction, a two-order digital tracking loop is used to enable a tracking intermediate variable V(Z) and a multi-beam lectronic scanning gain coefficient K0 to be multiplied, a new beam direction theta(Z) is obtained, and finally, the beam direction is updated through the waveform control software of the waveform control computer, after deviation is corrected, the real-time target position is transmitted to a beam forming unit, and self tracking on the dynamic target is completed.

To obtain a radar system capable of obtaining an appropriate angular precision by calculating an angle error based on distributions of relative speeds and angles of reflecting points, and of obtaining the appropriate angular precision including an axis deviation angle by simultaneously calculating the angle error and the axis deviation angle. A radar system mounted on a movable body is provided with a radar device that calculates relative speeds and azimuth angles of plural reflecting points; an azimuth angle error estimating device that estimates an error of the azimuth angle calculated by the radar device based on the relative speeds and the azimuth angles of the plural reflecting points; and a correcting device that corrects the azimuth angle calculated by the radar device by using the azimuth angle error estimated by the azimuth angle error estimating device.

This application discloses a control device for controlling a motor configured to drive an oscillatory cyclo-speed reducer including an oscillatory gear portion formed with at least one hole at an eccentric position. The control device includes an angle acquirer for acquiring input information about an input rotational angle indicating a rotational angle of the motor, an estimator for estimating an angular error between the input rotational angle and an output rotational angle indicating a rotational angle of the oscillatory cyclo-speed reducer based on a quantity of the hole(s) and a corrector for determining a compensation current value in correspondence to the angular error and setting a magnitude of a current to be supplied to the motor by correcting a command current value using the compensation current value.

In an optical space communication system, a remote controller is provided at an arbitrary position remote from an optical space communication apparatus. The optical space communication apparatus is provided with an interface device for exchanging status information of the operating apparatus, operation start setup/manipulation information or operating setup/manipulation information of the apparatus with the interface device. Communication between the remote controller and the interface device is made for a transmission light power, a transmission signal power, a reception light power, a reception signal power, a light beam transmission angle, a temperature of a predetermined portion in the apparatus, an angular error between the reception light and an optical axis of a light reception unit in the apparatus, a transmission light beam divergence angle or the like.

The invention relates to a three-axis acceleration sensor mounting error correcting method, and is used for correcting angle error between an acceleration sensor coordinate system and a vehicle coordinate system, so that a theoretical value of an acceleration sensor is obtained, the method is characterized in that, the method comprises the steps: the acceleration sensor is arranged on the vehicle, a measured value vector A0 of the acceleration sensor when the vehicle is static on a horizontal ground and a measured value vector A1 of the acceleration sensor when the vehicle acceleratedly moves on the horizontal ground are read, an error correction coefficient matrix K is calculated, wherein the K and other formulas are shown in the description, a theoretical value formula which is shown in the description of the acceleration sensor in the vehicle coordinate system is obtained, wherein vector Aa is a measured value of the acceleration sensor in a general condition. Compared with the technology in the prior art, the method considers vehicle pitch angle influence, the requirements of the measurement condition are low, the calculation method is simple, and the sensor coordinate axis error can be effectively eliminated.