36results about How to "Achieve high-precision calibration" patented technology

The invention discloses an accurate part positioning method based on binocular microscopy stereo vision, which belongs to the technical field of computer visual measuring and relates to an accurate precision part positioning method based on the binocular microscopy stereo vision. A binocular microscopy stereo vision system is adopted, two CCD (charge coupled device) cameras are adopted to acquire the images of the measured parts, the image information in the to-be-measured area on the measured part is amplified by a stereo microscope, a checkerboard calibrating board is adopted to calibrate the two CCD cameras, and a Harris corner point detecting algorithm and a sub-pixel extracting algorithm are adopted to extract feature points. The extracted feature points are subjected to the primary matching and correcting of matching point pairs, and the feature point image coordinates are inputted to a calibrated system to obtain the space actual coordinates of the feature points. The accurate part positioning method based on the binocular microscopy stereo vision solves the measuring difficult problems generated by the small size of the to-be-measured area, high positioning demand, non-contact and the like. The accurate positioning of the precision part is well finished by adopting the non-contact measuring method of the binocular microscopy stereo vision.

The invention discloses an intelligent vehicle laser sensor and an online camera calibration method. Laser data and image data are accurately calibrated via the steps of camera calibration, offline calibration of a three-dimensional laser sensor and an image sensor, time alignment of laser data and image data, and online alignment of the laser sensor and the image sensor. The calibration system can be applied to multiple different road conditions and scene, to achieve online high precision calibration of laser and an image. After the laser and the image are calibrated, the information of the two sensors can be used for comprehensively analyzing a barrier and making an accurate decision, so that the method has is significant in sensing technology of an intelligent vehicle. Therefore, the technology can be widely applied to the fields of driverless vehicle visual navigation and intelligent vehicle visual assistance driving.

The invention discloses a method and a device for calibrating a three-dimensional micro tactile sensor. The method and the device are characterized in that: a three-dimensional micro tactile sensor fixing device, a micromovement input device, a CCD camera and a laser interferometer are arranged in a vibration isolation chamber; the three-dimensional micro tactile sensor is put on a rotary table through different clamping mechanisms; the micromovement input device realizes Z-axis coarse movement positioning of the three-dimensional micro tactile sensor and zero contact of the sensor and piezoelectric ceramics through a control device; the piezoelectric ceramics output amplitude signals to apply displacement constraint signals to the three-dimensional micro tactile sensor through a control system; an input-output relational graph is established through a signal acquisition system and computer software; and a calibration system of the laser interferometer tracks and measures the displacement constraint quantity of the piezoelectric ceramics so as to test and calibrate performance parameters of the three-dimensional micro tactile sensor. The method and the device calibrate performanceof the three-dimensional micro tactile sensor with multiple sensing modes, such as linearity, measuring range and precision.

The invention provides a method for calibrating an object-space telecentric microscopic vision system based on a microsphere target. Firstly, the camera model of the object-space telecentric microscopic vision system is obtained based on the telecentric imaging principle of the object-space telecentric lens; then, the iterative calculation formula of the camera model of the object-space telecentric microscopic vision system is obtained based on the nonlinear damped least square method; Finally, the microsphere target is used to perform m relative movements within the telecentric depth range of the microscopic vision system, and the iterative calculation formula is used to realize the calibration of the object-space telecentric microscopic vision system. The method of the invention has the characteristics of convenient operation and high calibration precision, and has good application prospects.

The invention discloses a system and a method for optical gauge sample stage calibration. Alignment of an optical path system is carried out under the condition that an ellipsometer is of a straight-through type. The method for the optical gauge sample stage calibration includes calibration of a front optical path and a back optical path. Due to a knob on an oblique incidence type crude regulation the sample stage of the ellipsometer, a polarization detection arm optical receiver hole can receive a part of light beams; the knob on the sample stage is finely regulated so that a cross cursor indicating the light beams can appear at the central position; and a system front portion and system back portion scan in the Z-axis direction with a step length 1, overall light intensity received by a detector at each height position is recorded, a light intensity curve is drawn, and the system automatically selects the position where the maximum light intensity value is located as the optimal relative height position of the sample stage. The system for the optical gauge sample stage calibration mainly comprises a light source, a polarizing arm, a front-arranged four-quadrant detector, a polarization detection arm, a spectroscope, an internally-arranged four-quadrant detector, a charge coupled device (CCD) detector and a computer. By means of the method for the optical gauge sample stage calibration, inclination angles and heights of the sample stage can be calibrated with high precision, besides, response is fast, and operation is simple.

The present invention discloses a calibration device and a calibration method for a super-resolution and traceable type white-light interference atomic force probe. The calibration device is used for conducting the calibration method. The core technologies of the device and the method are composed of a traceable super-resolution displacement measurement system, a white-light interference zero-level fringe positioning algorithm, an atomic force probe bending model and a calibration process. The calibration device is used for generating the deformation of the probe. The traceable super-resolution displacement measurement system is used for accurately acquiring the vertical displacement generated during the probe deformation process. The white-light interference zero-level fringe positioning algorithm is used for accurately acquiring the position of an interference fringe on the cantilever of the probe. The atomic force probe bending model is used for fitting the relationship between the vertical displacement and the position of the fringe. The calibration process comprises specific implementation steps. According to the technical scheme of the calibration device and the calibration method, the relationship between the vertical displacement and the position of the fringe can be accurately and quickly acquired. Therefore, the accurate measurement of a white-light interference atomic force probe scanning microscope is realized.

The invention relates to a solid rocket engine ground rotation test in-situ calibration device. The solid rocket motor ground rotation test in-situ calibration device comprises a switching device, a universal flexible component, a standard sensor, a force source loading device and a load bearing pier, wherein the switching device, the universal flexible component, the standard sensor, the force source loading device and the load bearing pier are coaxially and sequentially connected with one another; a standard simulation thrust is provided through the force source loading device; the standard sensor is used for reading the value of the standard simulation thrust; the standard simulation thrust is transmitted to a solid rocket engine through the universal flexible component and the switching device; and the value of the standard simulation thrust is compared with the measurement value of the working sensor of a solid rocket engine rotation test device, so that calibration can be carried out. Compared with an existing calibration device, the solid rocket engine ground rotation test in-situ calibration device is simple in structure, can effectively transmit the standard simulation thrust to the solid rocket engine under a condition that the solid rocket engine is rotating, and can achieve high-precision calibration of the solid rocket engine rotation test device.

The invention relates to a large-field-of-view camera calibration method based on four sets of collinear constraint calibration rulers, belonging to the field of visual measurement, and relates to a large-field-of-view camera calibration method based on four sets of collinear constraint calibration rulers. The calibration method arranges four sets of collinear constraint calibration rulers in the large-scale visual measurement field of view, uses the cross-ratio unlimited nature and linear constraints to solve the distortion parameters, and uses the spatial calibration control points to linearly solve the initial value of the calibration parameters, and finally combines the distortion Coefficients and calibration initial values ​​are optimized using the L-M optimization method, and the objective function is to minimize the reprojection error to obtain accurate results of camera calibration with a large field of view. The invention optimizes the calibration results as a whole by flexibly arranging the calibration control points in the large field of view measurement space and combining four sets of collinear constraint calibration rulers, and realizes the high-precision calibration of the large field of view camera, which has wide application prospects.

The invention relates to a method for calibrating the probe length of a REVO measuring head, and belongs to the field of precision testing technology and instruments. The method comprises the following steps that a ring gauge is fixed on a horizontally placed flat plate; the main axes of a measuring machine are moved so that the A axis of the measuring head is located in the zero position state, and the measuring ball center of the measuring head coincides with the central axis of the ring gauge; and the three main axes of the measuring machine are kept stationary, the measuring head A axis and the measuring head B axis are moved, two symmetrical points on the same section of the ring gauge are detected, data are returned according to the two detected points, and the probe length of the REVO measuring head is calibrated through projection calculation. According to the method, calibration is carried out in a state that the three main axes of the measuring machine are stationary, so thatprobe length calibration errors caused by movement errors of the three main axes of the measuring machine and probe length calibration errors caused by misalignment between the axis of the B axis ofthe REVO measuring head and the axis of the ring gauge can be avoided, high-precision calibration of the probe length of the REVO measuring head can be realized, and the method can be applied to measurement.

The invention discloses a method and device for hand-eye calibration of a manipulator based on three-dimensional object recognition, wherein the calibration method includes: step S1, obtaining the first calibration data of the calibration object in the three-dimensional viewing angle coordinate system; step S2, obtaining the calibration The second calibration data of the object in the mechanical arm coordinate system; step S3, according to the first calibration data and the second calibration data, using the ICP iterative closest point algorithm to solve: the coordinates in the three-dimensional viewing angle coordinate system to The transfer matrix in the robot coordinate system. This calibration method can still achieve high-precision calibration in an environment with weak light intensity, and has simple steps and strong operability, which overcomes the shortcomings of existing calibration methods such as low precision, complicated steps, poor operability, and large impact of light.

The invention discloses a method for calibrating the B-axis zero error of a REVO probe, which is applied to a non-orthogonal coordinate measurement system and belongs to the field of precision testing technology and instruments; the invention comprises the following steps: placing a square ruler on a flat plate placed horizontally, placing Adjust the working surface M of the square ruler to be parallel to the X direction of the measuring machine and then fix it; fix the square ruler close to the working surface N perpendicular to the working surface M of the square ruler; keep the three main axes of the measuring machine stationary, so that the A axis of the REVO probe is in a suitable position , Use the B-axis rotation of the REVO probe to detect two symmetrical points on the ruler; according to the calculation of the B-axis angle of the two detection points, the zero error of the B-axis of the probe can be calibrated. When the three main axes of the measuring machine are stationary, the present invention avoids the situation that the angle of the articulated arm changes due to the measurement force during the calibration process and introduces additional calibration errors, and realizes high-precision calibration of the B-axis zero error of the REVO probe, which can Used in precision measurement.

The present invention relates to an on-line camera calibration method based on the fuzzy image of a small target. Obtain an identifiable target image; establish a mathematical model of target feature point positioning uncertainty, and solve the positioning uncertainty of each feature point; take the target feature point positioning and parameter uncertainty as constraints, and use nonlinear optimization methods to solve the camera High-precision solution of internal and external parameters; this method does not need to consider the camera focus space and target size, and only needs a small high-precision target to be placed close to the lens to achieve ultra-high-precision camera calibration under conditions of large image blur and noise . The invention is suitable for on-line calibration of a camera with a large field of view and a shallow depth of field or even a camera in use, and has great flexibility and adaptability.

The invention discloses a method for establishing and calibrating a multi-parameter model of an articulated arm coordinate measuring machine, relates to the technical field of precision measurement, expands the original 23-item error model of an articulated arm coordinate measuring machine into a 59-item error model, and greatly increases the number of joints The number of structural parameters of the arm coordinate measuring machine error model improves the accuracy of the joint arm coordinate measuring machine. The establishment and calibration method of a multi-parameter model of an articulated arm coordinate measuring machine provided by this application adds the shaft shaking error term to the original articulated arm coordinate measuring machine error model, and establishes a multi-parameter error model of an articulated arm coordinate measuring machine to realize High-precision calibration of an articulated arm coordinate measuring machine.

The invention discloses an on-orbit absolute radiation calibration method for an optical remote sensor based on a reflector array. The reflector array is used as a reference target, and the linear regression calculation is used to separate target reflected radiation from large-pass radiation, earth-atmosphere coupled radiation, and ground objects. Heat radiation. On-orbit absolute radiometric calibration of optical remote sensors in the mid-infrared band is achieved through on-site measurements of atmospheric optical thickness, temperature and humidity pressure profiles, and mirror reflectivity measurements combined with atmospheric absorption gas transmittance calculations. The mid-infrared band optical remote sensor on-orbit absolute radiation calibration technology of the present invention is based on ground measured data, does not rely on radiation transmission calculations, and reduces the influence of factors such as aerosols and atmospheric models. This calibration technology can realize mid-infrared Band optical remote sensor with full dynamic range and high precision calibration.