155 results about "Transfer alignment" patented technology

A system determines three-dimensional attitude of a moving platform using signals from two closely spaced Global Positioning System (GPS) antennas. The system includes three rate gyroscopes and three accelerometers rigidly mounted in a fixed relationship to the platform to aid in determining the attitude. The system applies signals from one of the two GPS antennas to sufficient channels of a GPS receiver to support navigation. The system applies signals from a second of the two GPS antennas to the additional receive channels to support interferometry. The system resolves the ambiguity normally associated with the interferometric heading solution by having closely spaced GPS antennas, and uses interferometry to refine a coarse heading estimate from a GPS plus Inertial Measurement Unit (IMU) transfer alignment solution. The system achieves sub-meter spacing of the two GPS antennas by merging many temporal interferometric measurements and the attitude memory provided by the IMU time-history solution.

The invention provides a transfer aligning method of an airborne distributed POS (Position and Orientation System). The method comprises the following steps of: modeling deflecting motion of an aircraft wing by using a mechanical method; augmenting a deflection deformation angle and deflection deformation angular velocity generated by the deflecting motion of the aircraft wing into state variables of Kalman filter; on this basis, designing a Kalman filter by using a velocity+posture matching method; carrying out transfer alignment on a sub inertial measuring unit by using velocity and posture reference information obtained after carrying out information fusion by using a main inertial measuring unit and a GPS (Global Positioning System); and finally obtaining corrected velocity and posture information of each sub inertial measuring unit mounting point. The transfer aligning method provided by the invention has the advantages of strong independency and high accuracy and can be used for improving the transfer alignment accuracy of the distributed POS when deflection deformation exists in the aircraft.

The invention discloses a near-space missile-borne strap-down inertial navigation system transfer alignment method based on a star sensor. The method comprises the following steps: 1) establishing a missile-borne strap-down inertial navigation system transfer alignment state equation by taking an inertial coordinate system (launching point coordinate system for short) on a carrier launching point as a navigation coordinate system and a strap-down inertial navigation system (SINS) on a missile to be launched as sub-inertial navigation; 2) calculating navigation information and observed quantity of the missile-borne strap-down inertial navigation system; 3) establishing a measurement equation; 4) by depending on the state equation and the measurement equation established, estimating a mathematics platform misalignment angle, a speed error, a position error and an installation error of the missile as well as flexural deflection of the carrier through a sparse grid integral kalman filter, and correcting a sub-inertial navigation system, thus finishing a transfer alignment process.

The invention discloses an airborne distribution type POS (position and orientation system) transfer alignment method based on parameter identification. An airborne distribution type POS comprises a high-precision master POS and a plurality of sub IMUs (inertial measurement units). Aiming at the problems of unknown elastic deformation and time change of a machine body, the elastic deformation angle of the machine body is regarded as a second-order Markoff process, the elastic deformation angle and the elastic deformation angle speed are expanded into state variables, the differences between the speeds and the postures of the master POS and the sub IMUs are measured, and a mathematic model of sub IMU transfer alignment is built; then, the Kalman filtering is performed and parameters of the second-order Markoff process are calculated and updated by virtue of the estimated elastic deformation angle and elastic deformation angle speed; at last, the updated second-order Markoff process parameters serve as initial filtering values at next moment to estimate the relatively accurate posture errors, speed errors and position errors of the sub IMUs, strapdown calculation results of the sub IMUs are corrected by virtue of the errors, and the relatively accurate positions, speeds and postures of the sub IMUs are calculated.

The invention relates to an airborne distributed POS transfer alignment method based on H infinity and CKF (Capacity Kalman Filtering) hybrid filtering. The method comprises the following steps: first, incorporating a deflection deformation error into measurement noise, determining a speed match measurement equation and an attitude match measurement equation, and primarily establishing a transfer alignment model of a system; designing nonlinear filtering, namely a CKF algorithm with high precision based on Kalman filtering; finally, achieving the purposes of weakening and eliminating the deflection deformation and a dynamic lever arm by utilizing good robust adaptive ability of H infinity filtering, designing an H infinity filtering algorithm, combining an H infinity filtering module and the CKF filtering, and designing a new H infinity and CKF hybrid filtering algorithm so as to estimate more accurate position, speed and attitude information of a slave inertial navigation system to complete transfer alignment. According to the airborne distributed POS transfer alignment method based on the H infinity and CKF hybrid filtering, the problem that the position, speed and attitude information of the slave inertial navigation system cannot be estimated accurately under the situation that the deflection deformation is difficult to model is solved, so that the airborne distributed POS transfer alignment method based on the H infinity and CKF hybrid filtering has the characteristics of high precision and strong anti-interference capacity.

The invention discloses a measuring method used piggyback twin antenna double measuring devices to interfere SAR base line motion. It includes the following steps: using twin antenna interference phase to gain carried machine roll angle; increasing observed quantity for base line near end antenna motion measurement integrated navigation system by co-ordinate transformation to restrain attitude measurement error diversity for routine inertial navigation and GPS integrated navigation system to increase base line near end antenna motion measurement precision; using the base line as strengthener to realize rough transfer alignment; using silicon MEMS inertial navigation output data and local relative navigation technique to correct the rough transfer alignment result to increase base line far end antenna motion measurement precision.

The invention discloses a ship large azimuth misalignment angle transfer alignment method based on volumetric Kalman filtering. The ship large azimuth misalignment angle transfer alignment method comprises the following steps: firstly, converting a specific force output of a secondary inertial navigation accelerometer to a navigation coordinate system; carrying out filtering processing on the specific force by utilizing a Butterworth digital low-pass filter; secondly, carrying out inertial navigation calculation on primary and secondary inertial navigation respectively; transmitting speed, posture and angular speed information of the primary inertial navigation to a navigation computer of the secondary inertial navigation; constructing measurement by utilizing speed error, posture error and angular speed error between primary and secondary inertial navigation system; then establishing a state equation and a measurement equation under a large azimuth misalignment angle condition by adopting a matching manner of a speed, a posture and an angular speed; finally, carrying out volumetric Kalamn filtering calculation by utilizing the established state equation and measurement equation and estimating a mounting error angle between the secondary inertial navigation system and the primary inertial navigation system, so as to finish transfer alignment. By adopting the ship large azimuthmisalignment angle transfer alignment method, the rapid and high-precision alignment problem of a ship under a condition of a large azimuth misalignment angle and a large lever arm error is solved.

The invention discloses an inertial navigation alignment performance evaluation method based on main inertial navigation attitude variation quantity assistance. The method comprises the following steps of implementing preheating preparation; performing navigation solution on a main inertial navigation system and a secondary inertial navigation system respectively; constructing a measurement equation of attitude variation quantity; constructing a performance evaluation measurement equation; performing Kalman filtration solution; performing reverse smoothing estimation; acquiring an attitude misalignment angle at a transfer alignment ending moment so as to realize alignment precision evaluation of transfer alignment of the inertial navigation system of a ship-borne weapon. The invention designs the inertial navigation alignment performance evaluation method based on the main inertial navigation attitude variation quantity assistance, linear motion information of GDPS position and speed is taken as main reference information, and the main inertial navigation attitude variation quantity is taken as auxiliary reference information, so that the requirements of accuracy evaluation on mechanical strength of a carrier can be reduced; integral output based on angular rate is taken as an observed value, so the influences on the inertial navigation alignment performance evaluation effect caused by external environmental interferences can be effectively inhibited, and the inertial navigation alignment accuracy evaluation performance of the ship-borne weapon can be improved.

The invention discloses a method for performing transfer alignment on a large azimuth misalignment angle of a ship in a polar region environment based on unscented Kalman filtering. The method comprises the following steps: I, completing starting and preheating preparation of a slave inertial navigation system, wherein the slave inertial navigation system completes primary binding by utilizing navigation parameters transmitted by a master inertial navigation system; II, performing inertial navigation calculation on the slave inertial navigation system, and synchronously acquiring the speed and attitude information of the master and slave inertial navigation systems output in a grid system to obtain speed and attitude errors so as to constitute and measure Z; III, according to navigation mechanics arrangement in the grid system, combining a grid navigation error equation, adopting a 'speed + attitude' matching manner, and establishing a system state equation and a measurement equation in the grid system; and IV, performing unscented Kalman filtering calculation, estimating the attitude misalignment angle of the slave inertial navigation system and the speed state estimated value, and completing transfer alignment. According to the method disclosed by the invention, the problem that the large azimuth misalignment angle cannot be subjected to transfer alignment in the polar region environment is solved, and the transfer alignment accuracy and applicability of the polar region are improved.

A prosthetic limb and process to digitally construct a prosthetic limb which includes first, digitally producing a modified mold of a residual limb via 3d scanners and software; constructing a test socket from the digitally modified mold and be equipped with an alignable system; accurately scanning the test socket, along with finalized alignment that has been recorded and adjusted by a certified practitioner to provide a 3-D Image of the finalized prosthetic alignment; transferring the finalized digital alignment of the test socket to the finalized digitally modified mold; once the modified model has received the transferred alignment, fabricating the type of hookup in the socket; i.e., plug fit, four hole, support drop lock, or any other type of industry standard connection or accommodation via basic 3D software; and once the desired prosthetic attachment is finalized, sending finished file to a 3-D printer to produce the definitive prosthetic device.

The invention provides a moving base transfer alignment method based on measurement of a misalignment angle. The moving base transfer alignment method comprises the following steps: step (1), completing coarse alignment by a sub-inertial navigation system by use of navigation parameters sent by a main inertial navigation system at fixed frequency, wherein the navigation parameters comprise speed, attitude and position information; step (2), establishing a system state equation and a system observation equation in a'measurement of misalignment angle and speed' matching way; step (3), constructing observables by the sub-inertial navigation system by used of the speed and posture information which is sent from the main inertial navigation system to the sub-inertial navigation system at fixed frequency; and step (4), performing iterative solution by virtue of Kalman filtration, estimating state estimated values of attitude misalignment angle, speed and position errors of the sub-inertial navigation system and correcting navigation information of the sub-inertial navigation system correspondingly so as to complete transfer alignment.

The invention discloses a communication-in-motion antenna multi-platform heading and attitude determination method based on transfer alignment. According to the method, an inertial measurement unit isinstalled on a satellite communication-in-motion antenna, multi-platform navigation calculation is carried out, and error compensation is carried out on a strapdown navigation algorithm result of theinertial measurement unit by using output information of navigation equipment on an antenna installation carrier and a transfer alignment algorithm; and finally, a multi-platform heading and attitudedata validity evaluation method is used to obtain heading and attitude information beneficial to improving the tracking performance of the antenna. The multi-platform heading and attitude determination method is established by combining the azimuth angle and signal intensity information of the antenna, the tracking performance of the antenna is improved, and the method has the advantages of no need of manual operation, simple implementation and wide application range.

The invention discloses a transfer alignment method and device based on visual movement modeling and belongs to application fields of visual navigation and transfer alignment fields. According to the requirements and the actual conditions, a high-speed camera is pre-arranged adjacently to a secondary inertial navigation so that the secondary inertial navigation to be detected is located in a photographing visual field of the camera; and the camera is fixedly connected with a primary inertial navigation. High-accuracy and high-precision characteristic point information of mark points of inertial navigation equipment is collected by the camera and image sequences obtained by a visual camera are used for carrying out dynamic parameter modeling on relative movement of the primary and secondary inertial navigations, even relative disturbance. On the basis of quickly establishing a dynamic model, the transfer alignment of the primary and secondary inertial navigations is realized by utilizing the transfer alignment to establish a Kalman filtering equation. The transfer alignment method and device based on the visual movement modeling can be used for the field needing to carry out alignment on the primary and secondary inertial navigations and solve the high-precision transfer alignment problem.

The invention discloses a distributed POS (position and orientation system) transfer alignment modeling method and a distributed POS transfer alignment modeling device of a bending deformation measuring network. The method comprises the following steps: establishing a six-degree-of-freedom bending deformation measuring network, and dispersing a flexible rod arm into a plurality of rod arm micro-sections with length not more than 10 cm according to a strain gradient of bending deformation of the distributed POS flexible rod arm; sticking six fiber grating sensors on the surface of each rod armmicro-section, calculating a three-dimensional deformation angle and three-dimensional deformation displacement under a main system carrier coordinate system by adopting a six-degree-of-freedom bending deformation solving method, and providing measuring information for distributed POS transfer alignment; and establishing a distributed POS attitude measuring equation based on bending deformation attitude compensation, and a distributed POS position measuring equation based on bending deformation position compensation so as to establish a transfer alignment system model. The invention also discloses the distributed POS transfer alignment modeling device of the bending deformation measuring network.

The invention discloses a method for measuring an airborne distribution type POS (point of sale) flexibility base line assisted by multiple cameras. The method comprises the following steps: performing transfer alignment on a low-accuracy sub-inertial measurement unit (sub-IMU) with the help of relative position posture information between a main IMU and the sub-IMU measured by the cameras by using a high-accuracy main inertial measurement unit (main IMU) to complete flexible multi-base line measurement. The method has the characteristics of high accuracy and strong anti-interference capacity,can be used for measuring flexible base line lengths between multiple loads when a carrier aircraft has flexural deflection, and improves the accuracy of the relative position posture between multiple loads. The invention further discloses a device for measuring the airborne distribution type POS flexibility base line assisted by the multiple cameras.

The invention belongs to the technical field of transfer alignment in inertial navigation, and particularly relates to a method for measuring hull deformation angle based on inertia instruments, such as a gyroscope, an accelerometer and the like, and an iterative filtering algorithm. The method comprises the following steps: 1, evaluating an estimated value (FORMULA) of the deformation angle by utilizing a Kalman filtering method; 2, analyzing the power spectrum of an angular velocity observation residual; 3, using the angular velocity observation residual and a specific force observation residual as Kalman filtering observation variables for iterative filtering; 4, through calculation repetition of the second step and the third step, constantly correcting an estimated result in the first step till a corrected value (FORMULA) of the deformation angle is close to but not equal to a true value (FORMULA). By the method, in allusion to the environmental characteristics that a large ship is low in speed and swings weakly, the measurement accuracy of the deformation angle in a vertical direction can be significantly improved; meanwhile, the method is relatively small in calculation amount, and is suitable for online real-time measurement.

The invention provides an inertial navigation system transfer alignment modeling method based on dual quaternion. A nominal dual quaternion between a main inertial navigation system and an auxiliary inertial navigation system is constructed, the dual quaternion is calculated to describe an auxiliary inertial navigation system carrier system relative to a main inertial navigation system carrier system, rotation and translation motion of the carrier systems are calculated, and a normal dual quaternion differential equation of transfer alignment is constructed by reasoning spinor expressions of relative rotation and translation motion of the main inertial navigation system and the auxiliary inertial navigation system and calculated; a dual quaternion error equation is obtained in combination with an accelerometer parameter error equation and a gyroscope error differential equation; a systematic observation equation is constructed by using the linear velocity of an accelerometer and the angular velocity of rotation of a gyroscope, an initial calibration parameter of the auxiliary inertial navigation system is calculated through kalman filter iteration, the effects of rotation and translation separation calculation on coning errors and sculling errors are eliminated, and the calculation accuracy and the calculation efficiency are effectively improved.