35 results about "Moment vector" patented technology

A method for identifying objects based on affine invariant moments of key points comprises the steps as follows: (1) image pretreatment: processing primitive collecting images so as to reduce influence of invalid information such as noises on the following process, enhance useful information and improve the image intensification; (2) main contour extraction: extracting the main contour to object edge images so as to obtain edge images of an outer contour and filter an interior contour and useless contour branches; (3) key frame extraction: calculating a mass center of the target at first based on target gray images dissected, then extending a plurality of rays to the periphery taking the mass center as an extension point so as to seek for the closest gray extreme point in each ray direction and take all the gray extreme points as the key point assembly; (4) invariable characteristic extraction of affine: extracting affine invariable characteristics of the main contour of the objects and calculating of multistage affine invariable moment vector; (5) object identification: identifying the objects through the characteristic proposed in the step (4) and outputting recognition result.

The invention discloses a sensorless mechanical arm collision detection method. The method comprises the steps that a rectangular projection matrix of the joint moment vector generated by the load ofthe tail end of a mechanical arm to the mechanical arm is calculated, and a moment transformation matrix of the load of the tail end of the mechanical arm is obtained according to the rectangular projection matrix; a mechanical arm body kinetic model is set up, a mechanical arm momentum deviation observer is set up according to various items in the kinetic model, the joint external moment vector of the mechanical arm is obtained through the momentum deviation observer, and the collision moment of the mechanical arm is calculated out according to the external moment vector and the moment transformation matrix of the load of the tail end of the mechanical arm; and the collision moment of the mechanical arm and a preset threshold value are compared, and whether a collision happens to the mechanical arm or not is judged. According to the collision detection method, collision detection of the mechanical arm with the load at the tail end can be achieved, and the method is simple, efficient and low in cost.

The invention relates to a method for regulating and controlling a posture of a spacecraft by the flow velocity and an actuating mechanism thereof and belongs to the field of control to the posture of the spacecraft. The method comprises the following steps that: according to a difference value of a current posture and a desired posture, a three-axis control moment vector required by the spacecraft is obtained, and according to a principle of the momentum moment, a relation between the three-axis control moment vector and the variation of a liquid fuel flowing angular velocity is obtained; according to the working principle of ring-shaped pipe liquid angular momentum exchange equipment, a relation between the liquid fuel flowing angular velocity and the change rate of a velocity vector inthe tangential direction of a pipe when liquid fuel flows is obtained; according to corresponding generated required conditions, the power of the pressure pump is controlled to apply work to the liquid, so that the flow velocity of the liquid is changed, and thus, the angular momentum H of a mass center of the spacecraft is changed and the posture of the spacecraft 10 is changed; and the changed posture is measured by a sensor and is compared with the desired posture and the steps are circularly repeated from the beginning of the step 1. The actuating mechanism for regulating and controlling the posture of the spacecraft by the flow velocity, which is used for implementing the method disclosed by the invention, comprises a liquid filled ring-shaped pipe, the pressure pump, an oil storage tank, a valve, a liquid outlet connecting pipe, a liquid return connecting pipe and a control mechanism.

The invention, which belongs to the technical field of motion control of the unmanned underwater robot, particularly relates to a six-degree freedom motion control system for operating type remotely operation vehicle (ROV). The method comprises: an ROV hydrodynamic model is established; controlling forces and moment vectors of an operating ROV at six freedom directions are established; a motion state of the operating type ROV in a body coordinate system {b} is calculated; a kinematical equation of an ROV is established; an angular speed motion state of the ROV body coordinate system is converted into one expressed in a geodetic coordinate system; an angular displacement state of the ROV body coordinate system is converted into one expressed in the a geodetic coordinate system; and according to an inputted ROV expected course angle in the geodetic coordinate system, an ROV expected course angel in the body coordinate system is calculated. According to the invention, the process of controlling the motion and attitude changes of the operating type ROV by an external control input can be simulated vividly. The method has the characteristic of capable of simulating various motion and control parameter changing processes of an ROV during the underwater working process vividly.

The invention discloses a vehicle three-dimensional centroid detection method, which comprises the following steps of: aiming at the problem that the stability of a vehicle is influenced by a centroidposition in the moving process, deducing a gravity center calculation formula of a complex geometry in principle, and establishing a mathematical model; taking contact points of four wheels of the vehicle and the ground as measuring points according to the established mathematic model, establishing coordinate positions based on the measuring points, detecting stress at stress points, deducing a gravity center three-dimensional coordinate position calculation formula and establishing a centroid detection model according to a principle that a moment vector of three-dimensional coordinates is '0', and giving force measuring points and coordinate values; and acquiring various parameters of the vehicle in the walking operation by means of sensors, transmitting the parameters to a computer simultaneously, and outputting signals to adjust walking operation parts of the vehicle based on a centroid position detected according to the centroid detection model and the acquired parameters by meansof the computer, and realizing steady-state driving of the vehicle. The vehicle three-dimensional centroid detection method can basically meet actual use requirements and design objectives.

A source for inducing an electromagnetic magnetic field, comprising: a substrate, a conductive layer coupled to the substrate, and a planar coil coupled to the substrate, wherein the planar coil comprises non-concentric rings, and wherein the non-concentric rings are configured such that a drive current applied across the non-concentric rings provides a magnetic field, and wherein the magnetic field comprises a moment vector that is tilted at an angle from the normal to a plane of the planar coil. Also provided are a method of electromagnetic tracking, a method of manufacture of a planar coil, and an electromagnetic sensor.

The invention discloses a satellite posture all-round controlling method based on a magnetic moment device and a flywheel, relating to an all-round posture controlling method for completing a satellite orbit-injection phase by using the magnetic moment device and the flywheel. The invention solves the problems of low reliability and short service life of the traditional satellite posture all-round controlling technology. The satellite posture all-round controlling method comprises the following steps of: 1, setting controller parameters according to the requirement of a control system; 2, measuring a geomagnetic field intensity vector Bb, a satellite angular velocity vector Wb and a solar azimuth, and sending the measured data to a satellite controller; 3, calculating an expected control moment vector Tm and a control magnetic moment vector Mm, and sending the control magnetic moment vector Mm to the magnetic moment device; 4, acquiring an effective solar azimuth vector Alfa; 5, calculating a control input moment vector Tw and sending to the flywheel; and 6, jointly completing the satellite posture all-round control by the magnetic moment device according to the control magnetic moment vector Mm and the flywheel according to the control input moment vector Tw. The invention is suitable for the field of satellite posture control.

An image comparison method constituted of: receiving images; point matching the images to identify tentatively corresponding points; responsive to the identified points, defining a plurality of first image tiles within the first image; defining a plurality of second image tiles within the second image, each corresponding to a respective first image tile; adjusting the intensity of a set of pixels responsive to the cumulative relative frequency of the respective pixel intensity within the respective tile; for each tile, applying a plurality of non-linear functions; for each function, separately determining a moment of the outcome of the respective non-linear function for each axis of the respective tile; for each first image tile and corresponding second image tile, determining a distance between the subspaces spanned by moment vectors; and responsive to determined distances, determining whether respective first and second image tiles comprise observations of the same portion.

The invention relates to liquid crystal meter pattern visual detection methods, and provides a liquid crystal meter pattern visual detection method based on normalization Zernike moment and gray matching. The method aims to solve the problems that image error detection rate is high, flexibility is poor, and images are rotated and zoomed. The method includes the implementation steps that 1, an image to be detected and a template image are obtained; 2, a horizontal moving image to be detected and a horizontal moving template image are generated; 3, the Zernike moment of the horizontal moving image to be detected and the Zernike moment of the horizontal moving template image are calculated; 4, a scale normalization moment Znm is generated; 5, a moment vector Zsrc and a moment vector Ztem are established; 6, a determining feature vector J is established; 7, the degree of gray matching is obtained; 8, an updated determining feature vector J' is obtained; 9, the percent of similarity is obtained; 10, a detection result is obtained. The method is applied to the field of visual detection on liquid crystal meter patterns.

The invention provides a method for obtaining handwriting information. In the method, a five-dimensional force / moment sensor module, an embedded microprocessor module and a true-color display module which are arranged in a handwriting device are utilized. The method comprises the following steps of: firstly initializing the five-dimensional force / moment sensor module, wherein the initialization comprises power supplying, zero-point modifying and interface drive requirement and temperature compensating; acquiring numerical values output by the five-dimensional force / moment sensor, thus obtaining five-dimensional force handwriting force data; performing decoupling operation on the five-dimensional force handwriting force data, thus obtaining real-time three-dimensional handwriting vector information numerical values and two-dimensional handwriting moment vector information numerical values; and performing corresponding formula calculation, thus obtaining real-time two-dimensional handwriting coordinate information and obtaining complete handwriting information. The method can be used for solving the problems that the handwriting information cannot be completely obtained in the existing handwriting information obtaining method, therefore, the security of signature information is improved, and the method provides a new guarantee means for ensuring the information security of important document signing in e-government or contract signing in e-business, and the like.

The invention discloses a control system arranged on a projectile body. The control system comprises a fixed wing canard rudder and a control assembly as a permanent magnet motor and a controller used for controlling the permanent magnet motor, wherein the control assembly is arranged at a control cabin on the front part of the projectile body; the permanent magnet motor comprises a rotor, a stator and a bearing; the stator is fixedly arranged on a longitudinal shaft of the projectile body; the rotor is arranged at the periphery of the stator; the rotor and the stator are connected through the bearing; the controller is arranged in the control cabin, and is connected with the longitudinal shaft through a control circuit; the fixed wing canard rudder is arranged on the outer wall of the rotor, and comprises two pairs of rudder plates with a fixed rudder angle; one pair of rudder plates is reverse in deflecting direction, and is used for providing external pneumatic angular moment needed for reverse rotation of the canard rudder; and the other pair of the rudder plates is the same in deflecting direction, and is used for providing pneumatic-control moment vector of posture adjustment of the projectile body. The control system arranged on the projectile body is arranged, so that cost and the size of the control cabinet of a mortar projectile can be greatly reduced, and a cost-benefit ratio is greatly increased.

The invention relates to a method for regulating and controlling a posture of a spacecraft by the flow velocity and an actuating mechanism thereof and belongs to the field of control to the posture of the spacecraft. The method comprises the following steps that: according to a difference value of a current posture and a desired posture, a three-axis control moment vector required by the spacecraft is obtained, and according to a principle of the momentum moment, a relation between the three-axis control moment vector and the variation of a liquid fuel flowing angular velocity is obtained; according to the working principle of ring-shaped pipe liquid angular momentum exchange equipment, a relation between the liquid fuel flowing angular velocity and the change rate of a velocity vector in the tangential direction of a pipe when liquid fuel flows is obtained; according to corresponding generated required conditions, the power of the pressure pump is controlled to apply work to the liquid, so that the flow velocity of the liquid is changed, and thus, the angular momentum H of a mass center of the spacecraft is changed and the posture of the spacecraft 10 is changed; and the changed posture is measured by a sensor and is compared with the desired posture and the steps are circularly repeated from the beginning of the step 1. The actuating mechanism for regulating and controlling the posture of the spacecraft by the flow velocity, which is used for implementing the method disclosed by the invention, comprises a liquid filled ring-shaped pipe, the pressure pump, an oil storage tank, a valve, a liquid outlet connecting pipe, a liquid return connecting pipe and a control mechanism.

The present invention belongs to the technical field of inertial navigation calibration, and particularly relates to a method for eliminating shaking impact of a rotation table during high precision inertial navigation system calibration. The method comprises: firstly establishing a direction cosine matrix between a real-time vector coordinate system and a starting moment vector coordinate system; then constructing a direction cosine matrix between the starting moment vector coordinate system and a starting moment earth coordinate system; and obtaining an attitude matrix between the real-time vector coordinate system and a geographic coordinate system, wherein attitude information of a stationary state end moment is obtained. With the present invention, the technical problem of impact on calibration precision by the rotation table shaking factor during a system level calibration process of the high precision inertial navigation system is solved; and gyro output information is adopted to real timely track attitude change of the inertial navigation system due to rotation table shaking so as to eliminate adverse effects caused by the rotation table shaking, improve inertial navigation system calibration precision, and reduce requirements on rotation table locking precision during the calibration process.

The invention provides an aircraft aerodynamic characteristic on-line identification method based on a backtracking self-adaptive algorithm. The aircraft aerodynamic characteristic on-line identification method comprises steps: (1) equivalently transforming the product term of the inverse of a rotational inertia matrix and a moment vector in an aircraft angular velocity kinetic equation into a Phi<T>(k)Theta* form, carrying out discretization processing on the transformed product term, and obtaining an aircraft angular velocity difference equation; wherein Phi<T>(k) represents a signal vector,Theta* represents a parameter truth vector, and the parameter truth vector is a column vector including an aerodynamic characteristic parameter to be identified; (2) establishing a mathematical modelof an angular velocity estimation virtual system, and making an angular velocity estimation error and a parameter estimation error be Phi<T>(k)[Theta(k)-Theta*], wherein Theta(k) represents an estimated value of the parameter truth vector; (3) establishing a backtracking performance formula of the angular velocity estimation error, combining a backtracking updating rule to obtain Phi (k) in realtime, resolving the Theta(k) by means of the backtracking self-adaptive algorithm, making the angular velocity estimation error omega-wave(k) approach zero, and resolving the aerodynamic characteristic parameter to be identified according to the value of the Theta(k). The aircraft aerodynamic characteristic on-line identification method has a lower calculated amount and a lower demand on the computer, and has operability.