185results about How to "Improve Guidance Accuracy" patented technology

Disclosed is an auxiliary device for driving vehicle, which can guide the vehicle traveling at a correct speed according to the way. A valarm, which is used to tell the driver that it is overspeed, in variation transition area is set below that in fixation transition area. Set a lower valarm before entering into the variation transition area. Thus, in the variation transition area, the vehicle speed can decrease adequately to complete the set steering value. And in the fixation transition area, the vehicle speed increases to shorten running time.

The invention discloses a dual-band co-aperture flat array antenna which is applied to multiband homing heads and intelligent ammunition guidance systems. The dual-band co-aperture flat array antenna comprises a single-ridge waveguide slot array surface, a substrate integrated waveguide slot array surface, single-ridge waveguide slot array feed networks and a substrate integrated waveguide slot array feed network. The single-ridge waveguide radiation slot array surface comprises a plurality of rows of parallel single-ridge waveguide radiation slot line arrays; a substrate integrated waveguide radiation slot array comprises a plurality of rows of parallel substrate integrated waveguide radiation slot line arrays; an antenna array surface is divided into four quadrants; the feed networks respectively feed array surfaces of the four quadrants so as to have the condition of realizing a single-pulse function; each quadrant has two sets of feed networks for respectively feeding the single-ridge waveguide slot line arrays and the substrate integrated waveguide slot line arrays; the single-ridge waveguide slot array surface works in an X-band; the substrate integrated waveguide slot array surface works in a Ka-band; arrays of two forms have a common aperture and do not mutually affect; and the problem of electromagnetic wave blocking caused by non-coplanar array surfaces is solved.

The invention relates to a precise process procedure for internal and external moulding surfaces of an antenna dome. The precise process procedure comprises the following main steps: (1) datum grinding process; (2) test process; (3) antenna dome installation process; (4) coarse and fine grinding process of external moulding surface of the antenna dome; (5) external moulding surface test process; (6) antenna dome installation and conversion process; (7) coarse and fine grinding process of internal moulding surface of the antenna dome; (8) test process; and (9) electrical thickness test process. The invention further relates to active position-finding technological equipment supporting installation of the antenna dome outside a machine, which consists of an external moulding surface special fixture (20), an internal moulding surface special fixture (30), a position finder (71) and a position finder (72), a position-finding workstation (40) and the like. The active position-finding technological equipment significantly improves the installation accuracy and the installation reliability of the antenna dome, significantly improves the working accuracy and the yield of the antenna dome, which in particular improves the coaxial accuracy by two grades or above two grades. By adopting the active position-finding technological equipment supporting installation of the antenna dome outside the machine, the debugging difficulty is significantly reduced; the installation and debugging time is reduced; the and utilization ratio of a numerical control grinder specially used for the antenna dome is effectively improved.

The invention discloses a deep learning-based reentry prediction correction fault-tolerant guidance method for a hypersonic aircraft, and belongs to the technical field of aircraft navigation guidanceand control. The method comprises the following steps of firstly, balancing the rudder deflection of an aircraft under a fault condition, selecting an attack angle profile within a feasible attack angle range, and simultaneously obtaining the lift and drag coefficients of the aircraft; then, enabling the attack angle profile to be substituted into a reentry process constraint equation to obtain areentry corridor meeting the requirements, and enabling the reentry corridor to be converted into a roll angle amplitude constraint; estimating the change amount delta CL and delta CD between the lift and drag resistance coefficient of the aircraft relative to the lift and drag coefficients of the normal aircraft, and combining the reentry terminal constraint equation to obtain an inclination angle amplitude; utilizing the inclination angle reversal logic based on the course angle error corridor to obtain an inclination angle symbol; and finally, calculating the inclination angle profile by using the inclination angle amplitude and the inclination angle symbol, and combining the attack angle profile to obtain the guidance command meeting the requirement after the fault. The method is highin guidance precision, good in algorithm instantaneity and capable of meeting the requirement of fault-tolerant guidance.

The invention discloses a real-time monitoring method for growth characters of tea trees in intensive cultivation. The method comprises the following steps: performing real-time data acquisition by a tea tree living body growth character data acquisition device based on online location, transmitting the acquired data to an artificial comprehensive management center through a wireless communication way to process, wherein the acquired data comprises current location data acquired by a locating mechanism, fresh tea leaves spectrum data acquired by a high spectrum imaging sensor, and average growth height of fresh tea leaves measured by an ultrasonic wave sensor, and judging the best fresh tea leaf picking time based on that the data and a picking judgment model established off line are combined by the artificial comprehensive management center. The picking judgment model comprises a bud size growth measurement model based on average growth height, a yield correlation model and a quality correlation model based on the high spectrum image data. The real-time monitoring method for the growth characters of the tea trees in intensive cultivation is beneficial to realizing of intensive cultivation and automation in planting of the tea trees.

Method of automatic target angle tracking by sum-and-difference monopulse radar covers radiolocation sphere and specifically monopulse direction finding systems. It can be used in order to increase guidance accuracy, for example, for anti aircraft missiles and of unmanned aerial vehicles to radar targets such as: radio beacons; aerial vehicles reflecting the radio signal that illuminates them; aerial vehicles and ground-based devices radiating radio signals and jamming signals. The aim of the method consists in the assurance of reliability and stability and in the enhancement of guidance accuracy of automatic target angle tracking due to elimination of automatic tracking losses and great errors arising during the influence of the signals of orthogonal polarization or polarization close to it.The proposed method provides full protection from polarization jamming for all types of monopulse radars.

A mechanism for aligning a hypodermic needle or other probe with a predetermined location within a patient has a radio-transparent guide with a lengthwise slot for accommodating the needle. A pair of radiopaque rings spaced at opposite ends of the guide enables the surgeon to align the needle with the predetermined location and advance the needle in a continuous and steady movement toward the predetermined location in spite of the intermittent activation and deactivation of a two-dimensional x-ray apparatus. A slot in each of the rings, moreover, forming gaps in alignment with the lengthwise guide slot permit the guide to be removed as the needle approaches the predetermined location.

The invention relates to a beam-target coupling sensor belonging to the field of photoelectric sensors, which overcomes the problems with conventional monitoring systems including high difficulties in design, manufacture, and assembling, high cost, high liability to undesired phenomena such as distortion and scattering, as well as low ensurance for targeting accuracy and reliability concerning special targets. The sensor includes three monitoring elements including an upper one, an intermediate one, and a lower one, each including a CCD, a micro object lens, a laser reflector, and an annular LED light source for monitoring the spatial position and posture of a target. The annular LED is used for illuminating the target. An incident laser beam on a target point is reflected onto the image surface of the CCD via the laser reflector. A vacuum motor and a ball screw transmission pair are used to realize focusing of the upper and lower micro monitoring systems, and an electric micro displacement platform is used to realize focusing of the intermediate micro monitoring system. In addition to accurate and fast guiding, the invention realizes zero impact of the target on light beam guiding because of indirect cast of laser light thereon, thus achieves improved adaptability to different targets.

The invention discloses a multiple interceptor collaborative detection and guidance integrated type intercepting method and system. On the basis of an aircraft relative motion relation and a double-sight collaborative detection error model, an interception model containing collaborative detection information is established; by taking intercepting miss distance, maneuvering energy consumption minimizing and effective modulation of an sight separation angle as control and optimization targets, a system performance constraint function is determined, and through system order reduction, and on thebasis of optimal control theory, an optimal guidance law is determined; and collaborative interception is carried out on a penetration device according to the optimal guidance law, and the optimal guidance law can ensure that multiple aircrafts has the collaborative detection effect in the collaborative guidance process. By adopting the intercepting method and system, the collaborative detection and guidance precision is improved, and meanwhile, the integrated design of multiple interceptors on the two links of cooperative detection and guidance is realized.

The invention provides a guidance information extraction method of a strapdown homing seeker, which comprises the following steps that (1) a body line-of-sight azimuth angle and a body line-of-sight altitude angle of the seeker in an airborne coordinate system o-xbybzb are acquired; (2) measurement information of the strapdown homing seeker is processed; (3) a missile-target relative distance vector in the airborne coordinate system and a component of a movement velocity of a target relative to an aircraft in the airborne coordinate system are calculated; (4) an inertia line-of-sight azimuth angular rate of the aircraft at the current hour and an inertia line-of-sight altitude angle rate of the aircraft at the current hour in the airborne coordinate system are calculated; and (5) results obtained in Step (4) serve as guidance information and are sent to the strapdown homing seeker. To overcome the defects in the prior art, body line-of-sight angular measurement information and gyro angular velocity measurement information are used directly to extract an inertia line-of-sight angular velocity, so that the guidance precision is improved, the design difficulty of a guidance system is reduced, and the guidance information extraction method can be widely applied to various strapdown homing guidance weapons.

The invention relates to a precision positioning device comprising a base, moveable stage and four double parallelograms connecting the stage to the base. Each double parallelogram comprises six deformable vertices forming six pivots so that the stage can move in translation in a reference plane. Thanks to the four double parallelograms, the moveable stage is over-constrained so that the undesired rotational motions are very limited. The precision positioning device can further comprise a moveable platform connected to the moveable stage thanks to flexure strips. The moveable platform is over-constrained to only move in translation according to the Z axis.

The invention discloses a finite time integral sliding mode terminal guidance law based on a super-twisting algorithm. The guidance law comprises the following steps: step 1, establishing a three-dimensional target-missile relative motion equation; step 2, designing a guidance law. A stability analysis is conducted on the guidance law. The invention provide the finite time integral sliding mode terminal guidance law based on the super-twisting algorithm by combining an integral sliding mode, a super-twisting algorithm and a finite time disturbance observer. According to the finite time integral sliding mode terminal guidance law based on the super-twisting algorithm, the finite time can be converged, the buffeting phenomenon can be eliminated, so that the maneuvering acceleration of a target can be better estimated, and the guidance accuracy is high; and the guidance law can be used for intercepting high-speed large-maneuvering targets such as unmanned aerial vehicles, ballistic missiles and the like, and has a wide application prospect.

The invention belongs to the technical field of air vehicle guidance and provides a self-adaptive weighting differential game guidance method aiming at a high maneuvering target. The method includes deriving a differential game guidance law under the conditions of symmetrical complete information and asymmetrical incomplete information according to different information modes; self-adaptively adjusting a penalty coefficient in a quadratic index according to estimation results of a state filter and a current maneuvering capacity; and finally, switching the different information modes according to estimation errors and self-adaptively changing a pursuit strategy to further form the self-adaptive weighting differential game guidance method. According to the self-adaptive weighting differential game guidance method, state information measured by a sensor is fully utilized, the information modes are timely adjusted according to changes of outside environments, the problems that reasonable evidences for setting target penalty coefficients are absent and ordinary differential game guidance laws are conservative are effectively solved, guidance accuracy of air vehicles is effectively and scientifically improved, and the method has high application values.

A single frame detection method of infrared weak object based on neural network and morphology includes collecting a training sample with various point object and background first, structuring neural network for optimizing said training element and combining it with revision morphology operator to structure morphological filter for making background estimation, using primary threshold to remove of interference point then using secondary threshold and neural network classifier to remove off noise point for achieving high detection probability and high false alarm probability.

The invention discloses a device for data acquisition of fertility characteristics of a tea tree living body based on online positioning. Four vertical supporting rods (2) are arranged on four corners of a rectangle covering the tea tree plantation zone; a colored mark (3) is arranged at the top end of each supporting rod; a guide rail (1) is arranged on each of the two long sides of the rectangle; four pulleys and a motor (20) used for driving the supporting rods are arranged at the bottom of a frame (5); an omnibearing visual sensor (9) is fixed onto a tripod (12) arranged at the top end of the frame; a computer (7), a storage battery (8), an ultrasonic sensor (16) and a wireless transmitter (14) are further arranged on the frame; a hyperspectrum sensor is also arranged at the top of the frame; the device for data acquisition of fertility characteristics of the tea tree living body based on online positioning has the characteristic of high automation degree, so as to provide infrastructure for fine plantation of tee trees.

The present invention provides an axial machining device comprising a tool-carrier spindle rotatable in a housing, the housing housing a transmission system causing the spindle to advance automatically relative to the housing under the effect of the tool-carrier spindle being driven in rotation, the transmission system including an advance gearwheel screwed onto the spindle, the device including a resilient return member urging the advance gearwheel in a first axial direction opposite to the advance direction of the spindle, and also including a first rolling bearing having rolling members rolling on an undulating raceway having an axial component, thereby periodically urging the advance gearwheel to move in a second direction opposite to the first, such that rotation of the spindle is accompanied by axial vibratory motion.

The invention provides a method and a device for estimating line-of-sight angle zero error by using an active radar seeker. The method comprises the steps of: calculating inertial navigation accordingto signals collected in real time by an inertial measurement unit in strap-down inertial navigation system to obtain flight path information of a missile in the strap-down inertial navigation system;in a case that every preset time is a sampling point, collecting beam signals during the search, interception and tracking of a target point by the active radar seeker, and calculating a first ballistic target line-of-sight angle of the missile relative to the target point in real time; collecting output data of a gyro and an accelerometer in the inertial measurement unit at each sampling point,and calculating a second ballistic target line-of-sight angle of the missile relative to the target point in real time according to the strap-down inertial navigation system principle; establishing astate equation, wherein the state variables in the state equation comprises the line-of-sight angle zero error; establishing a observation equation by using the ballistic target line-of-sight angle based on a observed value of the second ballistic target line-of-sight angle as observed quantity; and estimating the line-of-sight angle zero error according to a Kalman filtering method based on the state equation and the observation equation.

The invention discloses a semi-strapdown air-to-air missile guidance method based on a sliding mode variable structural theory. The semi-strapdown air-to-air missile guidance method comprises the following steps of 1, acquiring a missile-target line-of-sight turn rate differential model under a line-of-sight coordinate system; 2, acquiring a motion tracking sliding mode guidance rule; and 3, acquiring an expected line-of-sight turn rate xd. According to the method, a sigmoid function is applied to the sliding mode surface design of the motion tracking sliding mode guidance rule, the missile-target line-of-sight angular rate is improved at the initial guidance stage, the estimation to the target motion state is improved, the missile-target line-of-sight angular rate is made to be zero at the last guidance stage, the miss distance is lowered, and the missile hit precision is improved.

The invention discloses an aerospace vehicle re-entry guidance method capable of carrying out real-time analysis and construction. The method comprises the following steps that: 1) after the trajectory dip angle of the vehicle is zero, determining the corridor upper bound and the corridor lower bound of vehicle energy-drag acceleration; 2) generating a vehicle energy and drag acceleration characteristic profile; 3) correcting the vehicle energy and drag acceleration characteristic profile, and obtaining the correction amount of the vehicle energy and drag acceleration characteristic profile; 4) analyzing and constructing a re-entry guidance model; and 5) determining a vehicle dip angle instruction, and finishing vehicle re-entry guidance work. The guidance method disclosed by the inventionhas the advantages of being good in adaptive ability, high in accuracy, simple in calculation and easy in engineering implementation.

The invention relates to a control system and a control method for posture rail coupling under the shifting state of a big barycenter based on engine pre-swinging. The system comprises a barycenter estimation module, a pre-swinging angle calculation module, a procedure angel de-noising and compensation module, a control feedback bias calculation module, an incremental type PID control module and an equivalent servo swinging angle instruction and amplitude limiting module. The system provided by the invention is used for solving the problem of high-precision control on the shifting posture rail coupling of the big barycenter of an on-orbit aircraft. An excellent engineering application effect is achieved.

A disturbance compensation based RLV (reusable launch vehicle) approach landing guidance law acquisition method includes: firstly, calculating a height deviation and a lateral distance deviation according to an RLV approach landing nominal trajectory; secondly, using the Lyapunov theorem to obtain an anticipated flight path angle and a direction angle, namely virtual control laws according to a tracking deviation of the nominal trajectory; finally, adopting a backstepping design method to provide a guidance acquisition method capable of guaranteeing stability of a guidance loop. In a design process, an uncertainty upper bound of the guidance loop is obtained by analysis of aerodynamic data and inhibited by introduction of a compensation term, and consequently a guiding system has asymptotic stability in uncertainty of disturbance and the like. By adoption of the disturbance compensation based RLV approach landing guidance law acquisition method, influences of uncertainty on the RLV guiding system can be effectively overcome, and accordingly guiding precision is improved.

It is morphology filter automatic object detection method, which comprises the following steps: first to collect training samples to form heredity arithmetic for optimization train, wherein, the arithmetic adopts new range discretization code and self-adapting major / minor cross and dissociation operator; to use collected sample to train the structure element value by heredity arithmetic to form morphology filter based on Top-Hat operator; to filter the infrared object image; finally to do the division based on self=adapting threshold to detected multiple weak spots; to detect the object spots with high signal to noise rate by use of fixed threshold division.

The invention discloses a rotating projectile rotation speed measurement error compensation method based on geomagnetic information, so that rotating projectile rotation speed extraction precision can be improved. The method is characterized by, to begin with, installing a uniaxial magneto-resistive sensor in a projectile, wherein the sensitive axis of the uniaxial magneto-resistive sensor is vertical to the longitudinal symmetric axis of the projectile; installing a GPS antenna array conformal with the cone surface of a bullet head in the head portion of the projectile; then, selecting a measurement window, and extracting frequency of a projection signal F(t) of the uniaxial magneto-resistive sensor on the sensitive axis thereof in the measurement window, wherein the frequency serves as the projectile rotation speed at the central time ts in the measurement window; then, calculating rotation speed measurement error compensation value [delta]f(ts) of the projectile at the central time ts; and finally, carrying out error compensation on the rotation speed of the projectile at the time ts by utilizing the error compensation value [delta]f(ts) to obtain actual rotation speed of the projectile at the ts moment.

The invention discloses a semi-analytical Mars entry guidance method. The semi-analytical Mars entry guidance method comprises the following steps that a lander for a Mars atmosphere entry stage serves as a research object, Mars atmosphere is set to be motionless relative to the Mars surface, and the definition of a Mars fixed-connection coordinate system and a three-degree-of-freedom mass centermotion equation set of the lander under the coordinate system are given; the three-degree-of-freedom mass center motion equation set of the lander under the Mars fixed-connection coordinate system isprocessed, a numerical prediction model used for terminal longitudinal range errors is obtained, the influence of centrifugal acceleration and coriolis acceleration is taken into account, and meanwhile, the prediction model is updated online to ensure high-precision longitudinal range error prediction; and predicted terminal longitudinal range errors are taken as correction objects, the principleerror generating mechanism guided by an ETPC is analyzed and improved, and analytical terminal longitudinal range error correction is designed. According to the semi-analytical Mars entry guidance method, the landing precision is significantly improved, the obtained parachute-opening point distribution is very close to the computed results obtained by high-precision NPC guidance, and the validityof the method is indicated.

The present invention discloses a dual-polarized SAR image system which is low in target detection false alarm rate and high in detection rate. According to the technical scheme, a receiving and transmitting conversion module receives horizontal polarization signals of an H transmitting antenna and vertical polarization signals of a V polarization receiving antenna at the same time, the polarization form of the transmitting signals is changed, and a data acquisition board carries out digital down-conversion on acquired frequency mixing signal data and converts the frequency mixing signal datato a baseband; the H-channel pulse pressure module and the V-channel pulse pressure module are connected with a reference function module in parallel, the reference function module carries out Dopplerfrequency modulation, Doppler center estimation, distance bending correction, walking correction, parameter estimation and orientation matching filtering on data, and after a dual-polarization SAR image is obtained, determination fusion processing is carried out on the target to obtain a target detection result, and matrix singular value SVD decomposition is carried out on the covariance matrix corresponding to each pixel so as to obtain a characteristic value of the covariance matrix and a polarization entropy value of each SAR image pixel.

A process to control the trajectory of a spinning projectile. The projectile's accelerations are measured by means of an inertial unit in three axes within a reference linked to the projectile so as to prepare the piloting commands for the projectile's trajectory. The velocity vector V components (VX, VY, VZ) of the projectile are measured using a global positioning system (GPS) along three axes and within a land reference (GX, GY, GZ). Based on these measurements, the components (ΓX,ΓY,ΓZ) of the acceleration vector Γ are evaluated in the same land reference (GX, GY, GZ). At each of these measurements and periodical evaluations by the GPS, the Euler angles of the projectile are recalculated by combining the resultants of the velocity (V) and acceleration (Γ) measurements given by the GPS and those of the acceleration given by the inertial unit.

A RLV landing section guidance law acquiring method based on a sliding-mode control theory comprises steps of: calculating a height deviation and a lateral distance deviation according to an RLV landing section nominal trajectory; then, selecting an appropriate sliding-mode surface according to the tracking deviation of the nominal trajectory, and equivalently converting a RLV three-degree-of-freedom kinetic equation into a form described by the sliding-mode surface; and finally, designing the guidance law by using a Lyapunov method. In the design process, by analyzing aerodynamic data, the uncertainty upper bound of a guidance circuit is obtained and a compensation term is introduced to suppress the uncertainty so that the guidance system has asymptotic stability to the uncertainties such as disturbance. The method can overcome the influence of the uncertainty of the RLV guidance system so as to improve guidance precision, converts an original second-order system into a first-order system by introducing the sliding-mode control method, thereby achieving a visual design process.

The invention relates to a multi-step decision-making method for planning a trajectory around multiple no-fly zones. The method comprises the following steps of 1 impact point prediction calculation,2 boundary constraint handling scheme, 3 orientation adjustment scheme, 4 proportional navigation and 5 implementation of the method for planning the trajectory around multiple no-fly zones on the basis of a multi-step decision-making theory. Compared with an off-line planning method, the trajectory planning method has the advantages that the real-time performance is high, the on-line planning speed is high, and new avoiding instructions can be generated in real time according to the task and battlefield environment requirements; and compared with a traditional on-line planning method, the trajectory planning method has the advantages that the derivation process is simple, the condition of a large amount of randomly-distributed no-fly zones can be processed, and the trajectory planning method has the higher adaptability. According to the trajectory planning method, boundary constraints of the no-fly zones can be strictly guaranteed, a flying trajectory is smooth, the required overloadis small, and the trajectory planning method has the higher guidance precision.

The invention discloses an angular rate calculation and compensation method for table drift caused by a base motion. The method is applied to a three-axis inertial platform system, and comprises the following steps: measuring to obtain a Y1-axis angular rate omega y1 and a Z1-axis angular rate omega z1 of the base according to an external angular rate sensor on the base on which the three-axis inertial platform system is arranged; acquiring an internal relative rotation angle of the three-axis inertial platform system; and resolving according to the measured angular rate of the base and the internal relative rotation angle so as to obtain a drifting angular rate component, and compensating in a navigation equation. According to the method disclosed by the invention, the production mechanism of the table drift caused by the base motion in the three-axis inertial platform system is analyzed, so that the drifting angular rate is calculated to be used for compensation, and the navigation and guidance accuracy is improved.

The invention relates to a novel lead guiding method adopting multi-lead-angle superposition and end correction, and belongs to the technical field of aircraft guidance. The novel lead guiding methodadopting multi-lead-angle superposition and end correction is characterized in that a sight-angle signal and a yaw signal are measured through a guiding head and a gyroscope; then, lead angle signalsare intercepted multiple times according to the flight distance of an aircraft and the sight-angle signal, and the multiple lead angle signals are compared with a yaw angle to obtain a plurality of error signals for weight integration; afterwards, a large-sight-angle special processing link is designed for the condition that the sight angle of the tail section of the aircraft is excessively large,so that a guide signal of the tail section is prevented from being too large; and finally, the signals are subjected to proportional weight integration and are integrated to form a final guide signalwhich is output to an aircraft attitude stabilization circuit for tracking, and then the aircraft is guided to accurately fly towards a target. By the adoption of the novel lead guiding method, the problem that the setting of a single lead angle in the prior art cannot guarantee tracking of the tail section of the aircraft, and consequentially, a large target-missing rate is caused is solved.