54 results about "Rotation model" patented technology

The invention relates to a high-lift-to-drag-ratio hypersonic stable gliding reentry guidance method based on a drag profile. The method comprises the following steps that the first step, modeling ofa hypersonic flight vehicle is conducted; the second step, gliding distance analytic solution derivation is conducted; the third step, reentry track planning and tracking guidance are conducted; and the fourth step, a stable gliding trajectory tilt angle based on an earth rotation model is derived. The high-lift-to-drag-ratio hypersonic stable gliding reentry guidance method based on the drag profile has the advantages that a gliding distance analytic solution which is higher in accuracy and is based on energy is obtained, the form is simple, and application is convenient; the drag profile isplanned by using the energy as an independent variable, the drag profile is converted into the longitudinal lift-to-drag ratio under the rotating earth background, then a heeling angle is adjusted, tracking is conducted under the condition of the maximum lift-to-drag ratio, and transverse movement is controlled by a course error threshold; and in order to solve the reentry trajectory oscillation problem, the stable gliding trajectory tilt angle based on the earth rotation model is derived, and a trajectory damping technology using the stable gliding trajectory tilt angle as the feedback item is adopted to restrain oscillation.

The invention discloses an outfield precision testing method for a high-precision star sensor. Accuracy in calculation of a star pattern posture of the star sensor and frequency domain stripping of short-period error terms of the posture are realized by utilizing a procession correction formula, an earth rotation model, an atmosphere correction model and a power spectral density formula, and the posture measuring error of the star sensor can be rapidly and effectively analyzed and evaluated. According to the method, the hardware resource is not occupied, the method is realized by utilizing software and does not need the ground intervention. According to the method, by combining the posture identification principle of the star sensor and adopting a data smoothing method, the posture truth value of each frame star pattern moment is calculated, so that a foundation is established for the subsequent analysis on the posture measuring error; by adopting the method for combining the time domain and the frequency domain, the short-period error term is decomposed into an airspace low-frequency error, a high-frequency error and a time-domain error by virtue of the power spectral density analysis, so that reasonable data support is provided for further evaluation of the precision indexes of the star sensor, and the index performance of the star sensor can be improved.

The invention discloses a panoramic gaze camera space calibration method based on image splicing. The method includes the steps that firstly, a rotation model of a PTZ camera in a panoramic speed dome is built; secondly, multiple PTZ images shot by the PTZ camera and including all information of scenes are spliced to acquire a panoramic image; thirdly, based on the panoramic image, a mapping relation H2 between pixel points of the panoramic image and motion parameters of the PTZ camera and a mapping relation H1 between the pixel points of the panoramic image and pixel points in a fisheye image are built; fourthly, based on the mapping relation H1 and the mapping relation H2, a mapping relation H between the pixel points of the fisheye image and the motion parameters of the PTZ camera is built, and then panoramic gaze camera space calibration is achieved. By the adoption of the method, a horizontal deflection angle and a vertical deflection angle of the PIZ camera in the panoramic gaze camera can be accurately controlled, the monitoring position of a region of interest of the fisheye image shot by a selected fisheye camera is made to be at the center of the image shot by the PTZ camera, and then accurate positioning monitoring is achieved.

The invention discloses a wind farm wake correction method and system based on a CFD fluid mechanics model. The wind farm is divided into sectors with theta degree as one wind direction, and the windfield wake flow field is calculated by using the wind direction rotation model, which includes: according to the wind direction data of the wind measuring tower, the numerical simulation model extending along the X-axis direction according to the wind direction is established, and the grid three-dimensional solid model of the wind farm topography is established; based on the CFD wake model of theReynolds mean Nav i er-Stokes equation, the wake field in the main wind direction sector is obtained; by deflecting the terrain coordinates, the wake flow fields in other sectors with different wind directions are calculated; the wake flow fields are weighted by the wind frequencies in different wind direction sectors, and the final wake flow fields are obtained, which are used to calculate the wake effects between wind turbines. By adding topographic coordinate deflection, the invention adapts to numerical simulation of CFD fluid mechanics wake model with different wind direction angles, andat the same time, the wind frequency of each wind direction is considered for weighting, so that the wake region is more consistent with the real flow field.

Disclosed in the invention is a micro projection device comprising a display module (2), a diopter adjustment module (4) and lens modules (3). The lens modules (3) are fixedly installed at push plates (6) at the front and rear directions. The diopter adjustment module (4) includes a mounting plate (42), an adjusting shaft (45) installed at the mounting plate (42) in a relative rotation model, and an adjusting dial wheel (41) for driving the adjusting shaft (45) to make rotation. The display module (2) and a display adjustment threaded segment (452) of the adjusting shaft (45) are in threaded fit connection. The lens modules (3) and a lens adjustment threaded segment (453) are in threaded fit connection by the push plates (6). According to the invention, conditions are provided for realizing a precise and complicated optical adjustment design and debugging; and thus the user can carry out precise and complicated optical adjustment only by the adjusting dial wheel, thereby obtaining a good visual display effect with professional diopter adjustment.

The invention discloses a rotating bracket for wind-tunnel flow-field display test models, and the rotating bracket is provided for solving the problems that in a wind-tunnel flow-field display test, the adjustment on the levelness and rotating angle of the traditional test model is inconvenient and not high in precision. A bottom plate of the bracket is provided with a height adjusting bolt and a level instrument so as to meet the requirements on the levelness of the test model; the edge of a top plate of the bracket is provided with an angle scale line, and a rotating plate is arranged above the top plate, then the model can be rotated quickly and accurately so as to adjust the test model to a required wind attack angle; and besides the wind-tunnel flow-field display test, the bracket also takes the demands of a pressure measuring test for wind tunnels into consideration, holes are arranged in the centers of the top plate and the rotating plate so as to facilitate the connection between a pressure measuring pipe at the bottom of the model and a pressure measuring device below a floor board of a wind tunnel. The rotating bracket disclosed by the invention can be used for solving the problem that in a wind-tunnel flow-field display test, the manual adjustment on the levelness and rotating angle of a model is poor in precision; and the rotating bracket not only can be applied to wind-tunnel flow-field display tests on pure building structure scaled models in wind tunnels, but also can be applied to synchronous pressure measuring tests.

Systems and methods for registering hemispheric images obtained using a fisheye lens for panoramic viewing, relating to spatial alignment and colour balancing of complement half-side images derived from the hemispheric images. The systems and methods for spatial alignment determine the displacement of the digitized recorded images using a single translation and rotation model of distortion, which further evaluates the centre of projection, and the extent of translation and rotation. The system and method for colour balancing iteratively increase (or decrease) the values of pixels near the edge (discontinuity) between the two half-sides of an image, each time taking into consideration the average difference of pixel colour across a smaller strip of the edge near the pixel. This invention removes the colour differential but does not remove any detail underlying the features of the image.

A processing apparatus (6) for determining a respiration signal (34) of a subject (100) is presented. The processing apparatus (6) is configured to perform the steps of obtaining a movement signal (22) descriptive of a respiratory movement, determining a first quantity (24) descriptive of a rotation axis and/or rotation angle based on the obtained movement signal (22), and estimating a rotation axis (25) and/or rotation angle (26) based on the first quantity (24) and a rotation model, wherein the rotation model models the respiratory movement as a rotation around a single rotation axis. This model of the rotation can be further used as a feature for an instantaneous classifier descriptive of a movement artifact descriptive of a non-respiratory movement. Furthermore, a processing method, a respiration monitor (1, 91), a computer-readable non-transitory storage medium and a computer program are presented.

According to an aspect of the present invention, there is provided a pattern matching method of detecting an image of a detection target from a search image, comprising: obtaining a reference image of the detection target; generating the model edge image on a basis of the reference image; generating the edge extraction domain that is specified as a portion where the model edge image can exist by overlying a plurality of the model edge images obtained with at least one of rotating the model edge image within a predetermined range around a rotation center of the model edge image and translating the model edge image within a predetermined range; and performing pattern matching between the model edge image and the search edge image.

The invention provides a steering angle tracking method of an auto-driving automobile steering wheel with unknown EPS characteristics, belonging to the technical field of intelligent transportation. This method calculates the EPS steering torque command Mc_k according to the steering wheel steering angle measurement value and the steering wheel steering angle external command of the self-driving vehicle, Mc_k is derived from the difference between the discretized feedback controller algorithm torque Mfeedback_k and the feedforward compensator algorithm torque Mfeedforward_k based on the extended disturbance observation, Mfeedforward_k is used to compensate for various disturbances, including the unknown characteristics of EPS, on the front wheel rotation system of autonomous vehicles, Mfeedback_k is used to track the desired steering wheel angle of an autonomous vehicle, and Mc_k is used as the steering torque input to the EPS. As that steer moment is used as the wire control input interface, the whole EPS system is regarded as an actuator, and the influence of the unknown EPS characteristic, the road potholes, the wind resistance, the parameter uncertainty of the front wheel rotation model of the self-driving automobile, the slope gravity lateral component and the like on the steering angle tracking accuracy of the self-driving automobile steering wheel can be effectively suppressed.

The invention discloses a high-resolution remote sensing image intersection automatic identification method. The method comprises the following steps: S1, road element extraction; S2, communicating road frameworks: connecting adjacent road elements to form a complete road framework; S3, candidate intersection coordinates are generated, specifically, refining operation is conducted on the extractedroad skeleton, and road skeleton intersection points are obtained and serve as the candidate intersection coordinates; S4, constructing an intersection similarity index; and S5, identifying the intersection based on the block rectangular rotation model. According to the method, manual intervention is not needed, the intersection can be automatically extracted, and the extraction accuracy and integrity are superior to those of existing similar research results.

The invention discloses a chain type conveyor belt defect detection method based on image processing, and relates to the technical field of cigarette production. According to the invention, the methodcomprises the steps of erecting a camera on the side surface of a to-be-detected chain type conveyor belt, then collecting a real-time image of the chain type conveying belt through the camera; carrying out the scale scaling on the image through a Gaussian scale pyramid; using a pre-constructed multi-angle rotation model to position the image after scale scaling, obtaining the chain conveyor beltregions, converting the area of the chain conveyor belt into a grayscale image through differential multi-core Gaussian filtering, and filtering the grayscale image; enhancing the detection area of the chain type conveying belt by using the index change; carrying out image segmentation on the enhanced image, selecting and counting the characteristics of a defect-free chain type conveyor belt, andfinally comparing the characteristics of the defect-free chain type conveyor belt counted in advance with the corresponding characteristics of the chain type conveyor belt in an image collected in real time to judge whether the chain type conveyor belt has defects or not.

The invention discloses a three-dimensional line of sight estimation method based on an iris projection matching function. The method firstly calculates human eye parameters and establishes a human eye model by letting a user look at a plurality of standard points on a screen. Then, the spatial position and orientation of the iris are located by the matching function of the eye rotation model andthe iris projection, and the three-dimensional optical axis direction is obtained. Finally, the polynomial correction method is used to correct the optical axis and calculate the direction of the three-dimensional axis of view. This method uses depth camera to estimate 3D line of sight, which provides a fast, accurate and robust solution for 3D line of sight tracking in natural environment.

The present invention relates to a method, system and related devices for navigating between navigation points of a 3-Dimensional space where said 3-dimensional space comprises a plurality of navigation points. The method according to the present invention comprises the steps of detecting a current viewpoint rotation angle, further determining a degree of agreement of said current viewpoint rotation angle with a navigation point of said plurality of navigation points and subsequently activating a timing mechanism of the viewpoint activation, said timing mechanism comprising a delay for activating said timing mechanism of the view-point activation and a duration of an activation period of said timing mechanism at determining a certain degree of agreement of said current viewpoint rotation angle with a navigation point of said plurality of navigation points. The method further comprises the step of determining a degree of agreement of a portion of a viewpoint rotation angle trace with a viewpoint rotation model and adapting said at least one of said delay for activating said timing mechanism of said viewpoint activation and said duration of said activation period of said timing mechanism based on at least one of said degree of agreement of said current viewpoint rotation angle with a navigation point of said plurality of navigation points and said degree of agreement of said portion of said viewpoint rotation angle trace with said viewpoint rotation model.

The invention relates to a flutter model connecting device which is used for connecting a main airfoil in the flutter model with a rudder surface. The flutter model connecting device forms a no-hingestructure and is composed of a plurality of plate springs. The flutter model connecting device is configured in the extending direction of the main airfoil of the model. Two ends of the body part of the plate spring are respectively connected with the main airfoil and the rudder surface. The flutter model connecting device can realize simulation of rudder surface control rigidity and rudder surface rotation model, and furthermore can obtain linear control rigidity, higher rudder surface connecting strength, a relatively simple spring cross section form and a connecting designing form.

The invention provides an algorithm for automatically extracting a vertical plane on basis of vehicle-mounted laser scanning data. The algorithm for automatically extracting the vertical plane on basis of the vehicle-mounted laser scanning data includes the following steps that scanning data of a measured object are obtained through a vehicle-mounted laser scanning device; the obtained scanning data of the measured object are calculated to point cloud data of a set coordinate system; an algorithm of the vertical plane is found out; a vertical plane where the measured object is located is calculated according to the found algorithm of the vertical plane, a strip area where a horizontal projection of the measured object is located is obtained according to residual errors during fitting of a straight line while the calculation is performed, the strip area is fit to the straight line according to a least square method, and a horizontal projection of the vertical plane is designed according to width of the strip area and length of the cut-out strip area. The algorithm for automatically extracting the vertical plane on basis of the vehicle-mounted laser scanning data has the advantages that automatic finishing can be achieved, the algorithm is suitable for a surveying and mapping error basic theory, and defects that manual extracting is low in efficiency and inaccurate, and model rotating is required to check whether capturing is accurate or not can be overcome.

The invention discloses a three-steering-wheel control algorithm, which is used for controlling a tricycle body of an electric remote control tricycle to run along a specified path, a chassis of the tricycle body is in the shape of an equilateral triangle, a first steering wheel, a second steering wheel and a third steering wheel are installed at each endpoint of the equilateral triangle, and the steering wheels are of a walking and steering integrated structure. The control algorithm comprises a centripetal motion model, an oblique motion model and an in-situ rotation model, wherein the centripetal motion model is used for enabling the tricycle body to walk along a straight line, the oblique motion model is used for enabling the tricycle body to walk along an oblique line, and the in-situ rotation model is used for adjusting the driving angle of the tricycle body. By changing the walking speed and steering angle of the first steering wheel, the second steering wheel and the third steering wheel, omni-directional movement of the tricycle body is achieved, and in the movement process of the tricycle body, mutual cooperation and mutual assistance work of the first steering wheel, the second steering wheel and the third steering wheel under rigid connection is achieved through physical mathematical equations.

The invention discloses a method for rapidly fertilizing soil by using a potato-rice-rice rotation model. The method comprises the following steps: 1) planting winter potatoes: applying a base fertilizer and conducting three times of topdressing; 2) planting early rice: conducting twice topdressing and returning the whole amount of straw to the field; and 3) planting late rice: conducting three times of topdressing and returning the whole amount of straw to the field. The method can improve the soil nutrient property, rapidly increase the soil fertility, and rapidly fertilize the soil; at thesame time, the method can increase the crop yield, reduce application amount of chemical fertilizers, save production cost, and greatly improve planting efficiency.

The invention relates to the technical field of crane equipment, in particular to a computer vision-based building crane operation anti-accident auxiliary system, which comprises a key point detectionmodule, a model calculation module, a judgment processing module and a bounding box detection module connected with the model calculation module, the problems that in traditional crane operation, thesafety distance is judged inaccurately through human eyes, observation dead corners exist, great potential safety hazards exist, the observation efficiency is low, and communication is difficult aresolved. According to the invention, traditional manual command work is replaced, human eye errors are overcome through identification and distance measurement of key points, the detection accuracy isimproved, the labor force is liberated, and the operation risk is reduced; in addition, the safety risk of operation is further reduced through the rotation model and the inclination model, and the method is economical, practical and high in reliability.